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Promise and Reality of Post-Lithium-Ion Batteries with High Energy Densities
Abstract
Energy density is the main property of rechargeable batteries that has driven the entire technology forward in past decades. Lithium-ion batteries (LIBs) now surpass other, previously competitive battery types (for example, lead–acid and nickel metal hydride) but still require extensive further improvement to, in particular, extend the operation hours of mobile IT devices and the driving mileages of all-electric vehicles. In this Review, we present a critical overview of a wide range of post-LIB materials and systems that could have a pivotal role in meeting such demands. We divide battery systems into two categories: near-term and long-term technologies. To provide a realistic and balanced perspective, we describe the operating principles and remaining issues of each post-LIB technology, and also evaluate these materials under commercial cell configurations.
... In the first charge-discharge cycle, for Si@SiO x with longer heat treatment time, SiO x will consume a large amount of Li + to generate irreversible products such as Li 2 O and lithium silicate [24][25][26], thus forming a SEI film at the interface of active material (Reactions 1-2) [27,28]. This leads to a significant decrease in initial discharge specific capacity and ICE. ...
... As described in Eqs. (a-d), SiO x will consume a large amount of Li + to generate irreversible products Li 2 O and lithium silicate [24][25][26], forming an SEI film on the active material, which significantly reduces the initial discharge specific capacity and ICE [39] and increases R SEI . ...
Reducing silicon particle size in lithium-ion battery anodes not only mitigates surface stress, prevents pulverization, and reduces SEI film cracking but also significantly enhances surface area, thereby amplifying the impact of particle surface chemistry on performance. In this study, the surface of silicon particles with 80-nm diameter were oxidized in air to prepare Si@SiOx with a core–shell structure. We investigated the effect of different oxidation levels of the shell on the cycling performance of the nanosized silicon particles. The results showed that longer heating times decreased initial coulombic efficiency (ICE) but improved cycling performance. An interesting phenomenon was observed that, when the oxidation level was high, fast charging reduced battery capacity; while at lower oxidation levels, fast charging maintained or even slightly increased battery capacity. Based on electrochemical analysis, we proposed an explanation for this phenomenon: for small-sized nanoparticles with a large specific surface area, the effect of potential is particularly significant. The oxidation level of the particle surface affects the impedance of the SEI film, and high charge/discharge rates will also produce bias voltage, both of the two factors will limit the formation of crystallized Li15Si4 (c-Li15Si4). Reducing the amount of c-Li15Si4 can effectively improve the cycling performance of the electrode, but excessive bias voltage will sacrifice the lithium storage capacity of the electrode. For the designing of small size silicon particles, both factors should be considered.
... As the demand for electricity increases in our daily life, it is very attractive to search for electrical energy storage (EES) systems with high performance, reliability, and economy [1][2][3]. Lithium-ion batteries (LIBs) have been recognized as one of the most successful system thanks to their high energy density, good rate capability, and low self-discharge rate [4,5], and have been commercially used in electric vehicles and electronic products. Nevertheless, limited lithium resources and highly flammable organic electrolytes that may lead to serious safety issues of LIBs have prohibited their large-scale application [6]. ...
Zinc-ion capacitors (ZICs), combining the merits of both high-energy zinc-ion batteries and high-power supercapacitors, are known as high-potential electrochemical energy storage (EES) devices. However, the research on ZICs still faces many challenges because of the lack of appropriate cathode materials with robust crystal structures and rich channels for stable and fast Zn2+ ion transport. In this study, we synthesized a robust, conductive, two-dimensional metal–organic framework (MOF) material, zinc-benzenehexathiolate (Zn-BHT), and investigated its electrochemical performance for zinc storage. Zn2+ ions could insert into/extricate from the host structure with a high diffusion rate, enabling the Zn-BHT cathode to exhibit a surface-controlled charge storage mechanism. Due to its unique structure, Zn-BHT exhibited a good reversible discharge capacity approaching 90.4 mAh g−1 at 0.1 A g−1, as well as a desirable rate capability and good cycling performance. In addition, a ZIC device was fabricated using the Zn-BHT cathode and a polyaniline-derived porous carbon (PC) anode, which depicted a high working voltage of up to 1.8 V and a high energy density of ~37.2 Wh kg−1. This work shows that conductive MOFs are high-potential electrode materials for ZICs and provide new enlightenment for the development of electrode materials for EES devices.
... Lithium-ion batteries have become an indispensable power source for various portable devices and electric vehicles due to their high working voltage, long cycle life, safety and environment-friendliness [1][2][3][4][5]. However, with the increasing demand for longer battery life and higher energy density, it is essential to improve the energy density of lithium-ion batteries [6][7][8][9][10]. Although various high-specific-capacity energy anode materials have been extensively studied [11][12][13][14], the generation of SEI during the first charge of lithium-ion batteries results in irreversible lithium loss, leading to a decrease in energy density [15][16][17][18][19]. ...
In conventional lithium-ion batteries (LIBs), the active lithium from the lithium-containing cathode is consumed by the formation of a solid electrolyte interface (SEI) at the anode during the first charge, resulting in irreversible capacity loss. Prelithiation additives can provide additional active lithium to effectively compensate for lithium loss. Lithium oxalate is regarded as a promising ideal cathode prelithiation agent; however, the electrochemical decomposition of lithium oxalate is challenging. In this work, a hollow and porous composite microsphere was prepared using a mixture of lithium oxalate, Ketjen Black and transition metal oxide catalyst, and the formulation was optimized. Owing to the compositional and structural merits, the decomposition voltage of lithium oxalate in the microsphere was reduced to 3.93 V; when being used as an additive, there is no noticeable side effect on the performance of the cathode material. With 4.2% of such an additive, the first discharge capacity of the LiFePO4‖graphite full cell increases from 139.1 to 151.9 mAh g−1, and the coulombic efficiency increases from 88.1% to 96.3%; it also facilitates the formation of a superior SEI, leading to enhanced cycling stability. This work provides an optimized formula for developing an efficient prelithiation agent for LIBs.
... First, low-cost, plentiful materials like sodium are displacing lithium, paving the way for NIBs, MIBs, KIBs, and CIBs [281,282]. Second, lithium-sodium-sulfur batteries (LNSBs) are made by replacing the LiCoO 2 cathode with sulfur as a high energy density cathode material [283,284]. Furthermore, by utilizing its high theoretical capacity potential, passivated lithium metal with a protective layer as an anode material has been investigated [284,285]. Third, metal-oxygen batteries [286] have light weights and high energy densities, allowing chemical and electric energy conversion via OER and ORR. ...
Unsustainable fossil fuel energy usage and its environmental impacts are the most significant scientific challenges in the scientific community. Two-dimensional (2D) materials have received a lot of attention recently because of their great potential for application in addressing some of society’s most enduring issues with renewable energy. Transition metal-based nitrides, carbides, or carbonitrides, known as “MXenes”, are a relatively new and large family of 2D materials. Since the discovery of the first MXene, Ti3C2 in 2011 has become one of the fastest-expanding families of 2D materials with unique physiochemical features. MXene surface terminations with hydroxyl, oxygen, fluorine, etc., are invariably present in the so far reported materials, imparting hydrophilicity to their surfaces. The current finding of multi-transition metal-layered MXenes with controlled surface termination capacity opens the door to fabricating unique structures for producing renewable energy. MXene NMs-based flexible chemistry allows them to be tuned for energy-producing/storage, electromagnetic interference shielding, gas/biosensors, water distillation, nanocomposite reinforcement, lubrication, and photo/electro/chemical catalysis. This review will first discuss the advancement of MXenes synthesis methods, their properties/stability, and renewable energy applications. Secondly, we will highlight the constraints and challenges that impede the scientific community from synthesizing functional MXene with controlled composition and properties. We will further reveal the high-tech implementations for renewable energy storage applications along with future challenges and their solutions.
... Commonly used lithium-ion batteries (LiCoO 2 /Graphite), however, have a theoretical energy density limit. As a result, high-capacity Li metal secondary batteries (LMSBs) such as Li sulfur batteries and Li-air batteries using Li anodes have attracted attention [1][2][3][4]. Lithium is considered to be the best anode material because it has a low reduction potential (−3.045 V vs. the standard hydrogen electrode (SHE)), low density (0.534 g cm −3 ), and a correspondingly high theoretical capacity (3860 mAh g −1 ) [5][6][7]. However, Li metal anodes have the disadvantage of rapid capacity reduction over repeated charge/discharge cycles, owing to problems such as dendrite growth, dead Li generation, and continuous electrolyte consumption. ...
A novel anode consisting of a mixture of Cu powder and LiCl/Li13In3-coated Li powder was developed and tested for use in Li metal secondary batteries (LMSBs). The aim was to improve the electrochemical performance as suppress dendrite formation and volume change on the Li metal electrode. A LiCl/Li13In3 composite film was deposited on the surface of Li powder particles using a facile liquid treatment method. The coated Li powder was mixed with Cu powder to produce a Li–Cu composite electrode (LCE) for LMSBs. It has been proven through scanning electron microscopy (SEM) and analysis of the coating layer using X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and depth profile analysis that LiCl/Li13In3 has formed well on the surface of the Li powder. The coated LCE exhibited improved electrochemical properties in both the symmetric cell and full cell tests. Through electrochemical impedance spectroscopy (EIS) measurement, it has been determined that after 50 cycles, the impedance of the coated LCE is 98 Ω. In particular, even when a large amount of Li was used (40%, 1544 mAh g−1), it exhibited improved electrochemical behavior over 50 cycles in a symmetric cell test. In addition, in a full cell test with LiV3O8 as a cathode at a 2 C rate, the capacity retention was 96% after 50 cycles. SEM images showed that dendrite growth and volume change were suppressed by the novel electrode architecture.
... With the growing acknowledgment of lithium-ion batteries (LIBs) in 3C electronics, military industry and electric vehicles, it is important to further improve their energy densities [1][2][3]. Due to low theoretical capacity (372 mAh g −1 ), graphite anode cannot meet the power demand of LIBs. On the contrary, Li metal anode offers a theoretical capacity that is 10 times than graphite (3860 mAh g −1 ) and a low reduction potential of − 3.04 V [4][5][6]; thus, it is considered to be a strong contender for future LIBs anodes. ...
The application of Li1.2Mn0.54Ni0.13Co0.13O2 (LMNCO) cathode and Li anode in high specific energy batteries is impeded by particle cracking and electrode–electrolyte side reactions. Here, lithium bis(oxalate)borate (LiBOB) and dopamine (DA) are used as dual electrolyte additives to effectively stabilize the LMNCO cathode and Li anode. Specifically, LiBOB is preferentially reduced on the Li anode to participate in the formation of a B-rich inorganic solid electrolyte interface film, which suppresses the interfacial reactions between Li anode and the electrolyte. Meanwhile, DA is preferentially oxidized on the LMNCO cathode to form a thin and uniform cathode electrolyte interface film, which is beneficial to inhibit the decomposition of the electrolyte and reduce the corrosion of the LMNCO cathode. The facts are consistent with the results of density function theory. The synergetic effect of LiBOB and DA results in excellent electrochemical performance. Especially at 1 C, the capacity retention of the cell with the reference electrolyte is only 74.7% after 100 cycles, while the cell with dual-additive electrolyte is up to 92.6% after 400 cycles. This work provides a new idea to improve the electrochemical performance of Li anode and LMNCO cathode by functional electrolyte additives.
... Magnesium, with its high theoretical volumetric capacity of about 3832 mAh/cm 3 , 8 is abundant and cost-effective, contributing to reduced cell material costs. 9 During the charging and discharging of Li-ion batteries, the interface stability can be enhanced due to the formation of an Mg-Li phase, 10 leading to improved cycle performance and higher capacity. Moreover, a carbon-coated magnesium (MgC) anode has demonstrated superior material properties compared to conventional graphite (C) powder electrodes prepared by slurry coating. ...
This study presents the fabrication of an all‐solid‐state lithium‐ion battery using lithium manganese oxide (LiMn2O4; LMO) as the cathode, graphite (C), and carbon‐coated magnesium (MgC) as the anode, along with a silicate‐based solid electrolyte. To assess the charge/discharge mechanism, three polymeric membranes with varying weight percentages (5%, 30%, and 50%) of magnesium silicate are produced through battery‐cloth deposition (BCD) for use as the solid electrolyte. The findings reveal that enhancing the magnesium silicate content in the solid electrolyte (particularly at 50%) results in an increased specific capacity of the battery. The MgC anode exhibits a peak capacity of approximately 780 mAh/g during the third cycle, maintaining capacity retention of 100% over 26 cycles, addressing the issues of low specific capacity and self‐discharge in the solid‐state Li‐ion battery. Nevertheless, prolonged charge/discharge testing leads to an escalation in the surface roughness and porosity of the carbon coating on the MgC anode, resulting in a decline in capacity. These results demonstrate that the LMO‐BCD‐MgC battery system proposed in this study is a secure, eco‐friendly, and cost‐effective option with potential applications in energy storage.
... With the improvement of safety, environmental protection requirements, and the depletion of lithium resources, aqueous metal secondary battery is considered to be one of the potential energy storage devices that could replace lithiumion battery [1,2]. Among them, zinc secondary battery is regarded to have a wide application prospect owing to the high theoretical specific capacity (820 mAh g −1 ), low redox potential (− 0.76 V vs. SHE), excellent reversibility, low price, and high abundance of zinc [3][4][5][6][7]. However, there are some problems for Zn anode such as hydrogen evolution corrosion, dendrite growth, and electrode deformation during the charging and discharging process, which leads to the deterioration of battery capacity and cycling performance [8][9][10]. ...
Inhibiting dendrite growth and hydrogen evolution corrosion play a key role in improving the anode performance of zinc secondary batteries. ZnO@C/Bi composites with a unique core–shell structure were fabricated, in which the porous carbon coating acted as an ion sieve to inhibit dendrite growth, while the embedded Bi alleviated the hydrogen evolution corrosion of the anode due to its high hydrogen evolution overpotential. Although the design of carbon coating embedded with Bi improves the performance of zinc anode, the Bi content and carbon coating thickness still have great influence on the performance. According to the results, the corrosion current density decreases from 20.55 to 15.13 mA cm⁻² and increases to 17.22 mA cm⁻² with increasing Bi content (from 4.14 to 5.66 wt% and to 8.01 wt%), and the best corrosion resistance is obtained for ZnO@C/Bi with 5.66 wt% Bi content. Likewise, when the coating layer thickens from 2.28 to 5.48 nm and then to 14.26 nm, the average discharge-specific capacity increases from 586.87 to 591.59 mAh g⁻¹ and to 634.96 mAh g⁻¹, and the cycle life increases from 110 to more than 200 cycles. After the coating layer continues to increase to 20.38 nm, the average specific capacity decreases to 587.68 mAh g⁻¹. Consequently, the obtained ZnO@C/Bi with the optimal material composition (5.66 wt% for Bi content, 14.26 nm for carbon coating thickness) shows excellent electrochemical performance with a capacity retention rate of 95.79% (631.3 mAh g⁻¹) after 230 cycles.
... In addition, solid Li metal electrodes contain insignificant electrode porosity, and contain no inactive components, such as binders or conductive carbon, which are commonly used in graphite or silicon anodes negatively impacting their specific energies. These advantages allow LMB to provide both high gravimetric and volumetric energy densities, as shown in Fig. 2. [8][9][10][11][12] Nevertheless, practical applications of LMB face a critical challenge of low cycle life, with a rapid, rather than gradual, decay. The cycle life failure mode poses a challenge for battery life prediction which is an obligatory requirement for EV applications. ...
Lithium metal battery (LMB) technology is very attractive as it has the potential to offer energy densities greater than 1000 Wh L⁻¹. A thorough investigation of cell performance against various vehicle operational requirements is required for the successful deployment of this technology in practical electric vehicle applications. For instance, there have been several reports on the high reactivity of Li metal with electrolyte leading to continuous electrolyte consumption in LMB. Due to these parasitic reactions, electrolyte dries out and Li metal morphological changes occur leading to reduced cycle life of lithium metal batteries. In contrast, there are also claims of stable and long cycle life of LMB in several publications, although most of the results were obtained in coin cells. In this report we will take a closer look at the LMB cell to understand its performance and manufacturability. Our goal is to investigate and provide a thorough report on advances and challenges starting from the cell level down to component design of LMB.
... After Na, it is the most commonly found cation in the oceans. 9 The high relative abundance makes Mg-metal batteries a more economical and sustainable choice than batteries that rely on Li. 10 Additionally, the volumetric capacity of a Mg metal anode is nearly twice that of Li metal (3830 vs 2060 mAh ml −1 ). Though some studies have demonstrated the formation of Mg dendrites under select conditions, 11,12 Mg has been found to plate more smoothly than Li under comparable current densities due to its low self-diffusion barrier. ...
Mg batteries are a promising alternative to Li-based chemistries due to the high abundance, low cost, and high volumetric capacity of Mg relative to Li. Mg is also less prone to dendritic plating morphologies, promising safer operation. Mg plating and stripping is highly efficient in chloride-containing electrolytes; however, chloride is incompatible with many candidate cathode materials. In this work, we capitalize on the positive effect of chloride by using transition metal chloride cathodes with a focus on low cost, Earth-abundant metals. Both soluble and sparingly soluble chlorides show capacity fade upon cycling. Active material dissolution and subsequent crossover to the Mg anode are the primary drivers of capacity fade in highly soluble metal chloride cathodes. We hypothesize that incomplete conversion and chemical reduction by the Grignard-based electrolyte are major promoters of capacity fade in sparingly soluble metal chlorides. Modifications to the electrolyte can improve capacity retention, suggesting that future work in this system may yield low cost, high retention Mg-MClx batteries.
In the quest for sustainable energy storage technologies, lithium‐based batteries, despite their prominence, face limitations such as high costs, safety risks, and supply chain issues. This has propelled the exploration of alternative materials, with aqueous aluminum‐ion batteries (AAIBs) emerging as a promising candidate due to their high energy density, abundance, and cost‐effectiveness. However, the low equilibrium reduction potential of aluminum ions presents significant challenges, including hydrogen evolution and poor cyclability. Addressing these, the study pioneers the application of single‐atom catalysts (SACs) in AAIBs, leveraging their high atom utilization and stability to enhance aluminum deposition and suppress hydrogen evolution. Sn, In, Cu, and Ni SACs are evaluated through density functional theory analysis and experimental validation, with Sn SAC identified as the most effective. Subsequently, the Sn SAC based anode demonstrates enhanced performance, achieving stable cycling over 500 h at 0.5 mA cm⁻², significantly improved capacity retention (60 mAh g⁻¹@300 cycles), and rate performance (50 mAh g⁻¹@1 A g⁻¹) in full cell tests. This work underscores the potential of SACs in advancing AAIB technology and opens new pathways for energy storage solutions.
This study reports a facile and reliable operando X‐ray photoelectron spectroscopy (XPS) system for the characterization of the chemical state and electronic structure during Li‐plating/stripping in all‐solid‐state batteries (ASSBs). The measurement conditions (including manufacturing an in situ sample holder) and experimental parameters have been optimized through experimentation. The proposed system accurately defines the status of every metal interlayer component during real‐time battery operation (with simultaneous Li⁺‐ion in/out migration) under a repeating Li‐plating/stripping process. Moreover, it enables elucidation of ambiguous reaction mechanisms depending on the battery performance, such as the interlayer‐material effect on the efficiency and reversibility of the Li‐plating/stripping process, and changes in the oxygen‐containing bonds due to reaction with Li. The significance of the developed system is further validated by the usefulness and reliability of the valence band structure as a criterion for the analysis of lithium‐metal alloy formation and the progress of de‐alloying reactions.
Lithium-ion batteries (LIBs) have attracted significant attention due to their considerable capacity for delivering effective energy storage. As LIBs are the predominant energy storage solution across various fields, such as electric vehicles and renewable energy systems, advancements in production technologies directly impact energy efficiency, sustainability, and cost-effectiveness. The fast-growing demand for improved battery performance, such as higher energy densities and reduced costs, necessitates continuous innovation to meet these requirements. Furthermore, LIBs play a pivotal role, making it crucial to track and adopt emerging manufacturing techniques that contribute to cleaner and more efficient energy solutions. This review surveys multiple aspects of LIB manufacturing, beginning with electrode-level advancements in novel materials and process optimization and extending to the cell-level and innovative cell designs. It further investigates automotive battery production, the significance of battery management systems, and the interdisciplinary aspects of battery pack design. The emerging domain of all-solid-state technologies is also scrutinized, focusing on criteria, architectural designs, manufacturing processes, and the innovative application of 3D printing technology. Finally, this paper emphasizes the transformative potential of digitalization in LIB manufacturing, elucidating its advantages, challenges, and future prospects.
Graphical abstract
Alloying‐type anodes show capacity and density advantages for sodium/potassium‐ion batteries (SIBs/PIBs), but they encounter serious structural degradation upon cycling, which cannot be resolved through conventional nanostructuring techniques. Herein, we present an in‐depth study to reveal the intrinsic reason for the pulverization of bismuth (Bi) materials upon (de)alloying, and report a novel particle‐in‐bulk architecture with Bi nanospheres inlaid in the bulk carbon (BiNC) to achieve durable Na/K storage. We simulate the volume‐expansion‐resistant mechanism of Bi during the (de)alloying reaction, and unveil that the irreversible phase transition upon (de)alloying underlies the fundamental origin for the structural degradation of Bi anode, while a proper compressive stress (~10 %) raised by the bulk carbon can trigger a “domino‐like” Bi crystal recovering. Consequently, the as obtained BiNC exhibits a record high volumetric capacity (823.1 mAh cm ⁻³ for SIBs, 848.1 mAh cm ⁻³ for PIBs) and initial coulombic efficiency (95.3 % for SIBs, 96.4 % for PIBs), and unprecedented cycling stability (15000 cycles for SIBs with only 0.0015 % degradation per cycle), outperforming the state‐of‐the‐art literature. This work provides new insights on the undesirable structural evolution, and proposes basic guidelines for design of the anti‐degradation structure for alloy‐type electrode materials.
Physical Sciences book series aims to bring together leading academic scientists, researchers and research scholars to exchange and share their experiences and research results on all aspects of Physical Sciences. The field of advanced physical sciences has not only helped the development in various fields in Science and Technology but also contributes the improvement of the quality of human life to a great extent. The focus of the book would be on state-of-the-art technologies and advances in Physical Sciences.
Rechargeable magnesium sulfur batteries (MSBs) face issues like polysulfide shuttling, sluggish redox kinetics, and high cost, leading to dissatisfied practical demonstrations. Herein, simple battery configurations utilizing 100% sulfur are proposed on nine collectors and a low‐cost phenolate‐based magnesium complex (PMC) electrolyte to address these problems. Comprehensive studies indicate that the Cu collector is the most conducive to improving battery performance, not only facilitating the generation of magnesium sulfides during discharging but also effectively dissociating Mg─S bonds during charging. Moreover, Cu surfaces can effectively adsorb magnesium polysulfides (MgSx) and induce an insulator‐to‐metal transition of MgS, leading to a more effective suppression of the shuttle effect and the transfer of electrons. MXene interlayers are further introduced between electrodes to inhibit MgSx shuttling and enhance the interfacial electronic conductivity, as reflected by the reinforced high discharge voltage plateau at ≈1.7 V and stable long discharge voltage plateau at ≈1.2 V. The assembled MSBs exhibit the highest reported capacity of 1260 mAh g⁻¹S and an energy density of 1230 Wh kg⁻¹S with a cycle life of over 1000 cycles. This research contributes to the fundamental understanding of rechargeable MSBs and marks a significant advancement in optimizing cell designs for better performance.
Electrochemical energy storage and conversion systems (EESCSs), including batteries, supercapacitors, fuel cells, and water electrolysis technologies, enabling the direct conversion between chemical and electrical energies. They are key to the flexible storage and utilization of renewable energy and play an important role in future energy technologies. The physical and chemical properties of electrode materials significantly influence the performance of EESCSs, necessitating the development of materials with both high cost‐effectiveness and superior electrochemical storage and catalytic capabilities. Layered double hydroxides (LDHs), due to their unique properties as high surface area, evenly distributed active sites, and tunable compositions, makes themselves and the derivatives have become focal points in the EESCSs. This review summarizes recent advances of LDH and their derivates for diverse EESCSs applications, aims to elucidate the modification strategies of LDH materials and provide valuable insights for exploring LDH‐derived materials in various electrochemical devices, offering interdisciplinary perspectives for the rational design of LDH‐based materials.
In response to the critical challenges of interfacial impedance and volumetric changes in Li (1+x) Al x Ti (2‑x) (PO 4 ) 3 (LATP)‐based lithium metal batteries, an elastomeric lithium‐conducting interlayer fabricates from fluorinated hydrogenated nitrile butadiene rubber (F‐HNBR) matrix is introduced herein. Owing to the vulcanization, vapor‐phase fluorination, and plasticization processes, the lithium‐conducting interlayer exhibits a high elasticity of 423%, exceptional fatigue resistance (10 000 compression cycles), superior ionic conductivity of 6.3 × 10 ⁻⁴ S cm ⁻¹ , and favorable lithiophilicity, rendering it an ideal buffer layer. By integrating the F‐HNBR interlayer, the LATP‐based lithium symmetric cells demonstrate an extended cycle life of up to 1600 h at 0.1 mA cm ⁻² and can also endure deep charge/discharge cycles (0.5 mAh cm ⁻² ) for the same duration. Furthermore, the corresponding lithium metal full cells achieve 500 cycles at 0.5 C with 98.3% capacity retention and enable a high‐mass‐loading cathode of 11.1 mg cm ⁻² to operate at room temperature.
The irreversible chemistry of Zn anode, attributed to dendrite growth and parasitic side reactions, is the major constraint for the practical application of aqueous zinc ion batteries. Herein, polyelectrolyte complexes...
The state-of-the-art all-solid-state batteries have emerged as an alternative to the traditional flammable lithium-ion batteries, offering higher energy density and safety. Nevertheless, insufficient intimate contact at electrode-electrolyte surface limits their stability and electrochemical performance, hindering the commercialization of all-solid-state batteries. Herein, we conduct a systematic investigation into the effects of shear force in the dry electrode process by comparing binder-free hand-mixed pellets, wet-processed electrodes, and dry-processed electrodes. Through digitally processed images, we quantify a critical factor, ‘coverage’, the percentage of electrolyte-covered surface area of the active materials. The coverage of dry electrodes was significantly higher (67.2%) than those of pellets (30.6%) and wet electrodes (33.3%), enabling superior rate capability and cyclability. A physics-based electrochemical model highlights the effects of solid diffusion by elucidating the impact of coverage on active material utilization under various current densities. These results underscore the pivotal role of the electrode fabrication process, with the focus on the critical factor of coverage.
Batteries are the main component of many electrical systems, and due to the elevated consumption of electric vehicles and portable electronic devices, they are the dominant and most rapidly growing energy storage technology. Consequently, they are set to play a crucial role in meeting the goal of cutting greenhouse gas emissions to achieve more sustainable societies. In this critical report, a rational basic-to-advanced compilation study of the effectiveness, techno-feasibility, and sustainability aspects of innovative greener manufacturing technologies and processes that deliver each battery component (anodes, cathodes, electrolytes, and separators) is accomplished, aiming to improve battery safety and the circularity of end-products. Special attention is given to biomass-derived anode materials and bio-based separators utilization that indicates excellent prospects considering green chemistry, greener binders, and energy storage applications. To fully reach this potential, one of the most promising ways to achieve sustainable batteries involves biomass-based electrodes and non-flammable and non-toxic electrolytes used in lithium-ion batteries and other chemistries, where the potential of a greener approach is highly beneficial, and challenges are addressed. The crucial obstacles related to the successful fabrication of greener batteries and potential future research directions are highlighted. Bridging the gap between fundamental and experimental research will provide critical insights and explore the potential of greener batteries as one of the frontrunners in the uptake of sustainability and value-added products in the battery markets of the future.
Antimony oxides hold great competitive edges for lithium/sodium-ion storage on account of their large theoretical capacities. Composing antimony oxides particles with conductive supporters can greatly improve electrochemical performance, but still...
Gel polymer electrolytes (GPEs) are increasingly recognized for their potential to enhance lithium (Li)-ion batteries owing to their exceptional thermal stability and remarkable electrochemical performance. Despite these advantages, the practical application of traditional GPEs is hindered by their tendency to swell and their limited mechanical strength. To address these issues, this study introduces a bio-inspired rigid-soft coupling GPE comprising polyethylene oxide (PEO) and poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP), reinforced with Kevlar fiber fabric fabricated using a simple solution-casting method. The resulting PEO/PVDF-HFP/Kevlar (PPK) GPE demonstrates excellent ionic conductivity of 2.815 mS cm−1 and a Li-ion migration number of 0.571, alongside an ultra-high mechanical strength of 32.59 MPa. These features collectively contribute to the prevention of lithium dendrite growth and enhanced electrochemical performance of LiFePO4 cells, leading to stable cycling performance. The deployment of PPK GPE can pave the way for significant advancements in high-performance Li-ion batteries for various practical applications.
Our study explores the potential of β-LiVOPO 4 as a high-energy and stable cathode material for zinc-ion batteries, achieving a high working voltage through comprehensive characterization techniques.
The global importance of lithium-ion batteries (LIBs) has been increasingly underscored with the advancement of high-performance energy storage technologies. However, the end-of-life of these batteries poses significant challenges from environmental, economic, and resource management perspectives. This review paper focuses on the pyrometallurgy-based recycling process of lithium-ion batteries, exploring the fundamental understanding of this process and the importance of its optimization. Centering on the high energy consumption and emission gas issues of the pyrometallurgical recycling process, we systematically analyzed the capital-intensive nature of this process and the resulting technological characteristics. Furthermore, we conducted an in-depth discussion on the future research directions to overcome the existing technological barriers and limitations. This review will provide valuable insights for researchers and industry stakeholders in the battery recycling field.
Si/C composite material is a promising anode material for next-generation lithium-ion batteries due to its high capacity. However, it also exhibits significant initial capacity loss in a full cell due...
Pushing intercalation‐type cathode materials to their theoretical capacity often suffers from fragile Li‐deficient frameworks and severe lattice strain, leading to mechanical failure issues within the crystal structure and fast capacity fading. This is particularly pronounced in layered oxide cathodes because the intrinsic nature of their structures is susceptible to structural degradation with excessive Li extraction, which remains unsolved yet despite attempts involving elemental doping and surface coating strategies. Herein, a mechanochemical strengthening strategy is developed through a gradient disordering structure to address these challenges and push the LiCoO2 (LCO) layered cathode approaching the capacity limit (256 mAh g⁻¹, up to 93% of Li utilization). This innovative approach also demonstrates exceptional cyclability and rate capability, as validated in practical Ah‐level pouch full cells, surpassing the current performance benchmarks. Comprehensive characterizations with multiscale X‐ray, electron diffraction, and imaging techniques unveil that the gradient disordering structure notably diminishes the anisotropic lattice strain and exhibits high fatigue resistance, even under extreme delithiation states and harsh operating voltages. Consequently, this designed LCO cathode impedes the growth and propagation of particle cracks, and mitigates irreversible phase transitions. This work sheds light on promising directions toward next‐generation high‐energy‐density battery materials through structural chemistry design.
Hard carbon (HC) has emerged as one of the superior anode materials for sodium-ion batteries (SIBs), with its electrochemical performance significantly influenced by the presence of oxygen functional groups and its closed pore structure. However, current research on the structural adjustment of these oxygen functional groups and the closed pore architecture within HC remains limited. Herein, energy-efficient and contamination-free spark plasma sintering technology was employed to tune the structure of coconut-shell HC, resulting in significant adjustments to the content of carboxyl (decreasing from 5.71 at% to 2.12 at%) and hydroxyl groups (decreasing from 7.73 at% to 6.26 at%). Crucially, these modifications reduced the irreversible reaction of oxygen functional groups with Na+. Simultaneously, a substantial number of closed pores with an average diameter of 1.22 nm were generated within the HC, offering an ideal environment for efficient Na+ accommodation. These structural changes resulted in a remarkable improvement in the electrochemical performance of the modified HC. The reversible specific capacity of the modified HC surged from 73.89 mAh·g−1 to an impressive 251.97 mAh·g−1 at a current density of 50 mA·g−1. Even at 400 mA·g−1, the reversible specific capacity increased significantly from 14.55 to 85.44 mAh·g−1. Hence, this study provides a novel perspective for designing tailored HC materials with the potential to develop high-performance SIBs.
Catalysts for zinc‐air batteries (ZABs) must be stable over long‐term charging‐discharging cycles and exhibit bifunctional catalytic activity. In this study, by doping nitrogen‐doped carbon (NC) materials with three metal atoms (Fe, Ni, and Cu), a single‐atom‐distributed FeNiCu‐NC bifunctional catalyst is prepared. The catalyst includes Fe(Ni‐doped)‐N 4 for the oxygen evolution reaction (OER), Fe(Cu‐doped)‐N 4 for the oxygen reduction reaction (ORR), and the NiCu‐NC catalytic structure for the oxygen reduction reaction (ORR) in the nitrogen‐doped carbon nanoparticles. This single‐atom distribution catalyst structure enhances the bifunctional catalytic activity. If a trimetallic single‐atom catalyst is designed, it will surpass the typical bimetallic single‐atom catcalyst. FeNiCu‐NC exhibits outstanding performance as an electrocatalyst, with a half‐wave potential ( E 1/2 ) of 0.876 V versus RHE, overpotential ( E j = 10 ) of 253 mV versus RHE at 10 mA cm ⁻² , and a small potential gap ( ΔE = 0.61 V). As the anode in a ZAB, FeNiCu‐NC can undergo continuous charge‐discharged cycles for 575 h without significant attenuation. This study presents a new method for achieving high‐performance, low‐cost ZABs via trimetallic single‐atom doping.
Non-aqueous, rechargeable battery development is one of the most important challenges of modern electrochemistry. Li ion batteries are a commercial reality for portable electronics with intensive efforts underway to apply this technology to electro-mobility. Extensive investigations of high energy density Li-sulfur and Li-oxygen systems have also been carried-out. Efforts to promote high energy density power sources for electric vehicles have been accompanied by intensive work on the development of rechargeable sodium and magnesium batteries for load-leveling applications. The electrolyte solution is a key consideration in all batteries determining cell stability, cycle life, and safety. This review discusses the importance of solution selection for advanced, high-voltage, Li ion batteries, sodium ion batteries, as well as Li-sulfur, Li-oxygen and magnesium batteries. Li ion battery standard solutions are discussed and their further optimization is outlined. Limitations of Li metal electrodes are expla
MgTFSI2 is the only ether-soluble "simple" magnesium salt. The poor electrochemical performance ofMg electrodes in its solutions hinders its practicality as a viable electrolyte for Mg batteries. MgTFSI2/DME solutions were demonstrated to dissolve large quantities of MgCl2 and produce electrolyte solutions with superior performance, though the electrochemical performance, mainly in terms of reversibility, of MgTFSI2/MgCl2 (DME) solutions cannot yet compete with that of organometallic based electrolyte solutions. We believe that the solutions purity level governs the overall electrochemical performance, especially in solutions where a strong reductant (i.e Grignard reagent) is not present to act as an impurity scavenger. In this work, we alter the performance of the MgTFSI2/MgCl2 (DME) solutions through chemical and electrochemical conditioning and demonstrate the effect on the solutions electrochemical characteristics. We demonstrate relatively high reversible behavior of Mg deposition/dissolution with crystalline uniformity of the Mg deposits, complemented by a fully reversible intercalation/de-intercalation process of Mg ions into Mo6S8 cathodes. We also investigated LiTFSI/MgCl2 solutions which exhibited even higher reversibility than MgTFSI2/MgCl2 (DME) solutions, which we attribute to the higher purity level available for the LiTFSI salt.
Li-ion battery technology has become very important in recent years as these batteries show great
promise as power sources that can lead us to the electric vehicle (EV) revolution. The development of
new materials for Li-ion batteries is the focus of research in prominent groups in the field of materials
science throughout the world. Li-ion batteries can be considered to be the most impressive success story
of modern electrochemistry in the last two decades. They power most of today’s portable devices, and
seem to overcome the psychological barriers against the use of such high energy density devices on
a larger scale for more demanding applications, such as EV. Since this field is advancing rapidly and
attracting an increasing number of researchers, it is important to provide current and timely updates of
this constantly changing technology. In this review, we describe the key aspects of Li-ion batteries: the
basic science behind their operation, the most relevant components, anodes, cathodes, electrolyte
solutions, as well as important future directions for R&D of advanced Li-ion batteries for demanding
use, such as EV and load-leveling applications.
Silicon is receiving discernable attention as an active material for next generation lithium-ion battery anodes because of its unparalleled gravimetric capacity. However, the large volume change of silicon over charge-discharge cycles weakens its competitiveness in the volumetric energy density and cycle life. Here we report direct graphene growth over silicon nanoparticles without silicon carbide formation. The graphene layers anchored onto the silicon surface accommodate the volume expansion of silicon via a sliding process between adjacent graphene layers. When paired with a commercial lithium cobalt oxide cathode, the silicon carbide-free graphene coating allows the full cell to reach volumetric energy densities of 972 and 700 Wh l(-1) at first and 200th cycle, respectively, 1.8 and 1.5 times higher than those of current commercial lithium-ion batteries. This observation suggests that two-dimensional layered structure of graphene and its silicon carbide-free integration with silicon can serve as a prototype in advancing silicon anodes to commercially viable technology.
This work presents a new insight into the reduction mechanism of solid sulfur during the first step of cell discharge, that is, a 2.4 V plateau in Li-S batteries, by testing a specially designed cell with the solid sulfur electrically isolated from the carbon cathode and comparing it with a conventional cell. Importantly, the cell with the electrically isolated sulfur particles confined between two separators shows very normal operation even during the first cycle and provides the same result as a conventional cell after several cycles. Based on the controlled potentiostatic and galvanostatic experiments, we propose a reasonable reaction route: a portion of the electrically isolated solid sulfur (S-8) is dissolved in the electrolyte solution to form sulfur molecules, which can be electrochemically reduced to polysulfides on the carbon surface.
Layered Li and Mn rich cathode materials of the xLi[Li1/3Mn2/3]O-2 center dot(1-x)LiMn1/3Ni1/3Co1/3O2 (x = 0.2, 0.4, 0.6) were synthesized by a self-combustion method, characterized by XRD, SEM, HRTEM and Raman spectroscopy and studied as positive electrode materials for Li-ion batteries. The cathode material with x = 0.6 exhibits an initial high discharge specific capacity of 270 mAh g(-1) at C/10 rate in galvanostatic charge-discharge cycling, which decreases to 220 mAh g(-1) after 50 cycles. It also exhibits a high rate capability as compared to other composites. Structural studies using the electron diffraction technique with TEM and spectral studies by Raman spectroscopy indicate continuous structural changes upon cycling that include formation of a spinel phase. The electrochemical impedance spectra recorded at various potentials present evidence of a substantial increase in the charge-transfer resistance at potentials higher than 4.4 V during charge and also at potentials lower than 3.8 V during discharge. The chemical diffusion coefficient of Li(+)ions in these materials was calculated to be around 10(-13) cm(2) s(-1) and itreaches a minimum near 3.3 V from PITT studies. The minimum value of the diffusion coefficient of Li around 3.3 V potential can be explained as resulting from the formation of spinel phase upon cycling.
The oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) are traditionally carried out with noble metals (such as Pt) and metal oxides (such as RuO2 and MnO2) as catalysts, respectively. However, these metal-based catalysts often suffer from multiple disadvantages, including high cost, low selectivity, poor stability and detrimental environmental effects. Here, we describe a mesoporous carbon foam co-doped with nitrogen and phosphorus that has a large surface area of ∼1,663 m(2) g(-1) and good electrocatalytic properties for both ORR and OER. This material was fabricated using a scalable, one-step process involving the pyrolysis of a polyaniline aerogel synthesized in the presence of phytic acid. We then tested the suitability of this N,P-doped carbon foam as an air electrode for primary and rechargeable Zn-air batteries. Primary batteries demonstrated an open-circuit potential of 1.48 V, a specific capacity of 735 mAh gZn(-1) (corresponding to an energy density of 835 Wh kgZn(-1)), a peak power density of 55 mW cm(-2), and stable operation for 240 h after mechanical recharging. Two-electrode rechargeable batteries could be cycled stably for 180 cycles at 2 mA cm(-2). We also examine the activity of our carbon foam for both OER and ORR independently, in a three-electrode configuration, and discuss ways in which the Zn-air battery can be further improved. Finally, our density functional theory calculations reveal that the N,P co-doping and graphene edge effects are essential for the bifunctional electrocatalytic activity of our material.
High energy-density lithium-ion batteries are in demand for portable electronic devices and electrical vehicles. Since the energy density of the batteries relies heavily on the cathode material used, major research efforts have been made to develop alternative cathode materials with a higher degree of lithium utilization and specific energy density. In particular, layered, Ni-rich, lithium transition-metal oxides can deliver higher capacity at lower cost than the conventional LiCoO2 . However, for these Ni-rich compounds there are still several problems associated with their cycle life, thermal stability, and safety. Herein the performance enhancement of Ni-rich cathode materials through structure tuning or interface engineering is summarized. The underlying mechanisms and remaining challenges will also be discussed.
© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Mankind has been in a unending search for efficient sources of energy. The coupling of lithium and oxygen in aprotic solvents would seem to be a most promising electrochemical direction. Indeed, if successful, this system could compete with technologies such as the internal combustion engine and provide an energy density that would accommodate electric vehicle demands. All this promise has not yet reached fruition because of a plethora of practical barriers and challenges. These include solvent and electrodes stability, pronounced overvoltage for oxygen evolution reactions, limited cycle life and rate capability. One of the approaches suggested to facilitate the oxygen evolution reactions and improve rate capability is the use of red-ox mediators such as iodine for a fast oxidation of lithium peroxide. In this paper we have examined LiI as an electrolyte and additive in Li oxygen cells with ethereal electrolyte solutions. At high concentrations of LiI, the presence of the salt promotes a side reaction that forms LiOH as a major product. In turn, the presence of oxygen facilitates the reduction of I3- to 3I- in these systems. At very low concentration of LiI, oxygen is reduced to Li2O2. The iodine formed in the anodic reaction serves as a red-ox mediator for Li2O2 oxidation.
Lithium-oxygen batteries with high theoretical energy densities have great potential. Recent studies have focused on different cathode architecture design to address poor cycling performance, while the impact of interface stability on cathode side has been barely reported. In this study, we introduce CoO mesoporous spheres into cathode, where the growth of crystalline discharge products (Li2O2) is directly observed on the CoO surface from aberration-corrected STEM. This CoO based cathode demonstrates more than 300 discharge/charge cycles with excessive lithium anode. Under deep discharge/charge, CoO cathode exhibited superior cycle performance than that of Co3O4 with similar nanostructure. This improved cycle performance can be ascribed to a more favorable adsorption configuration of Li2O2 intermediates (LiO2) on CoO surface, which is demonstrated through DFT calculation. The favorable adsorption of LiO2 plays an important role in the enhanced cycle performance, which reduced the contact of LiO2 to carbon materials and further alleviated the side reactions during charge process. This compatible interface design may provide an effective approach in protecting carbon-based cathodes in metal-oxygen batteries.
Lithium (Li) metal is an ideal anode material for rechargeable batteries due to its extremely high theoretical specific capacity (3860 mA h g À1), low density (0.59 g cm À3) and the lowest negative electrochemical potential (À3.040 V vs. the standard hydrogen electrode). Unfortunately, uncontrollable dendritic Li growth and limited Coulombic efficiency during Li deposition/stripping inherent in these batteries have prevented their practical applications over the past 40 years. With the emergence of post-Li-ion batteries, safe and efficient operation of Li metal anodes has become an enabling technology which may determine the fate of several promising candidates for the next generation energy storage systems, including rechargeable Li–air batteries, Li–S batteries, and Li metal batteries which utilize intercalation compounds as cathodes. In this paper, various factors that affect the morphology and Coulombic efficiency of Li metal anodes have been analyzed. Technologies utilized to characterize the morphology of Li deposition and the results obtained by modelling of Li dendrite growth have also been reviewed. Finally, recent development and urgent need in this field are discussed.
The extremely high theoretical energy density of the lithium-oxygen couple makes it very attractive for next-generation battery development. However, there are a number of challenging technical hurdles that must be addressed for Li-Air batteries to become a commercial reality. In this article, we demonstrate how the invention of water-stable, solid electrolyte-protected lithium electrodes solves many of these issues and paves the way for the development of aqueous and nonaqueous Li-Air batteries with unprecedented energy densities. We also show data for fully packaged Li-Air cells that achieve more than 800 Wh/kg.
We systematically investigate polysaccharide binders for high capacity silicon anodes in lithium ion batteries to find critical factors for binder function. Analogous to the millipede?s strong adhesion based on adhesive pads located on each leg, xanthan gum exhibits the best performance by utilizing its double helical superstructure with side chains and ion-dipole interactions, revealing the great importance of the superstructure and charged interaction in the Si binder design.
Several commercial automotive battery suppliers have developed lithium ion cells which use cathodes that consist of a mixture of two different active materials. This approach is intended to take advantage of the unique properties of each material and optimize the performance of the battery with respect to the automotive operating requirements. Certain cathode materials have high coulombic capacity and good cycling characteristics, but are costly and exhibit poor thermal stability (e.g., LiNixCo1-x-yAlyO2). Alternately, other cathode materials exhibit good thermal stability, high voltage and high rate capability, but have low capacity (e.g., LiMn2O4). By blending two cathode materials the shortcomings of the parent materials could be minimized and the resultant blend can be tailored to have a higher energy or power density coupled with enhanced stability and lower cost. In this review, we survey the developing field of blended cathode materials from a new perspective. Targeting a range of cathode materials, we survey the advances in the field in the current review. Limitations, such as capacity decay due to metal dissolution are also discussed, as well as how the appropriate balance of characteristics of the blended materials can be optimized for hybrid- and electric-vehicle applications.
The effect of the electrolyte solution composition and the cycling protocol on the long-term cycling performance and surface chemistry of monolithic amorphous columnar silicon film electrodes was investigated using electrochemical tools, XPS, SEM and EDS. An excellent cycling stability of Si electrodes in fluoroethylene carbonate (FEC)-based electrolyte solutions was demonstrated. It relates to the ability of FEC to form polyenes, as well as to a high rate of HF formation in its water contaminated LiPF6 solutions, measured by F-19 NMR spectroscopy. We found that excellent passivation in FEC solutions related to a low content of oxygen containing moieties in surface films. Galvanostatic tests and spectroscopic analyzes revealed also a strong dependence of the composition and properties of the surface films on amorphous Si electrodes on the cycling procedure. Repeated deep discharge of Si electrodes down to 10 mV vs. Li/Li+ from the very beginning of the electrodes life ensures the formation of thin effective surface films on their surface and good cycling performance. Cycling stability of Si electrodes in LiPF6 solutions decreases in the following order FEC/DMC > 3,4-trans-difluoroethylene carbonate (DFEC)/DMC > ethylene carbonate (EC)/DMC > propylene carbonate (PC).
Rapid progress has been made in realizing battery electrode materials with high capacity and long-term cyclability in the past decade. However, low first-cycle Coulombic efficiency as a result of the formation of a solid electrolyte interphase and Li trapping at the anodes, remains unresolved. Here we report LixSi-Li2O core-shell nanoparticles as an excellent prelithiation reagent with high specific capacity to compensate the first-cycle capacity loss. These nanoparticles are produced via a one-step thermal alloying process. LixSi-Li2O core-shell nanoparticles are processible in a slurry and exhibit high capacity under dry-air conditions with the protection of a Li2O passivation shell, indicating that these nanoparticles are potentially compatible with industrial battery fabrication processes. Both Si and graphite anodes are successfully prelithiated with these nanoparticles to achieve high first-cycle Coulombic efficiencies of 94% to >100%. The LixSi-Li2O core-shell nanoparticles enable the practical implementation of high-performance electrode materials in lithium-ion batteries.
Na-ion batteries have been proposed as candidates for replacing Li-ion batteries. In this paper we examine the viability of Na-ion negative electrode materials based on Na alloys or hard carbons in terms of volumetric energy density. Due to the increased size of the Na atom compared to the Li atom, Na alloys would lead to negative electrode materials with roughly half the volumetric energy density of their Li analogs. Volumetric energy densities obtainable with sodiated hard carbons would also be significantly less than those obtainable with lithiated graphite. These findings highlight the need of novel ideas for Na-ion negative electrodes.
Unlocking the full potential of rechargeable magnesium batteries has been partially hindered by the reliance on chloride-based complex systems. Despite the high anodic stability of these electrolytes, they are corrosive toward metallic battery components, which reduce their practical electrochemical window. Following on our new design concept involving boron cluster anions, monocarborane CB11H12⁻ produced the first halogen-free, simple-type Mg salt that is compatible with Mg metal and displays an oxidative stability surpassing that of ether solvents. Owing to its inertness and non-corrosive nature, the Mg(CB11H12)2/tetraglyme (MMC/G4) electrolyte system permits standardized methods of high-voltage cathode testing that uses a typical coin cell. This achievement is a turning point in the research and development of Mg electrolytes that has deep implications on realizing practical rechargeable Mg batteries. A simple yet multifaceted magnesium monocarborane (MMC) based electrolyte was prepared. This remarkable halogen-free and benign system is compatible with Mg metal and displays the highest anodic stability reported to date. The non-corrosive nature of the MMC electrolyte enabled the examination of high-voltage cathodes in a coin cell, which is a critical step forward in realizing practical rechargeable Mg batteries.
Despite the recent considerable progress, the reversibility and cycle life of silicon anodes in lithium-ion batteries are yet to be improved further to meet the commercial standards. The current major industry, instead, adopts silicon monoxide (SiOx, x~1), as this phase can accommodate the volume change of embedded Si nano-domains via the silicon oxide matrix. However, the poor Coulombic efficiencies (CEs) in the early period of cycling limit the content of SiOx, usually below 10 wt% in a composite electrode with graphite. Here, we introduce a scalable but delicate pre-lithiation scheme based on electrical shorting with lithium metal foil. The accurate shorting time and voltage monitoring allow a fine tuning on the degree of pre-lithiation without lithium plating, to a level that the CEs in the first three cycles reach 94.9%, 95.7%, and 97.2%. The excellent reversibility enables robust full-cell operations in pairing with an emerging nickel-rich layered cathode, Li[Ni0.8Co0.15Al0.05]O2 even at a commercial level of initial areal capacity of 2.4 mAh cm-2, leading to a full cell energy density 1.5 times as high as that of graphite-LiCoO2 counterpart in terms of the active material weight.
The electrochemical behavior of Na-Ion and Li-Ion full cells was investigated, using hard carbon as the anode material, NaNi0.5Mn0.5O2 and LiNi0.5Mn0.5O2 as the cathodes. A detailed description of the structure, phase transition, electrochemical behavior and kinetics of the NaNi0.5Mn0.5O2 cathodes is presented, including interesting comparison with their lithium analog. The critical effect of the hard carbon anodes pretreatment in the total capacity and stability of full cells is clearly demonstrated. Using impedance spectroscopy in three electrodes cells we show that the full cell impedance is dominated by the contribution of the cathode side. We discuss possible reasons for capacity fading of these systems, its connection to the cathode structure and relevant surface phenomena.
Composite sulfur-carbon electrodes were prepared by encapsulating sulfur into the micropores of highly disordered microporous carbon with micrometer-sized particles. The galvanostatic cycling performance of the obtained electrodes was studied in 0.5 M Li bis(fluorosulfonyl)imide (FSI) in methylpropyl pyrrolidinium (MPP) FSI ionic-liquid (IL) electrolyte solution. We demonstrated that the performance of Li-S cells is governed by the formation of a solid electrolyte interphase (SEI) during the initial discharge at potentials lower than 1.5 V vs. Li/Li+. Subsequent galvanostatic cycling is characterized by a one plateau voltage profile specific to the quasi-solid-state reaction of Li ions with sulfur encapsulated in the micropores under solvent deficient conditions. The stability of the SEI thus formed is critically important for the effective desolvation of Li ions participating in quasi-solid-state reactions. We proved that realization of the quasi-solid-state mechanism is controlled not by the porous structure of the carbon host but rather by the nature of the electrolyte solution composition and the discharge cut off voltage value. The cycling behavior of these cathodes is highly dependent on sulfur loading. The best performance at 30°C can be achieved with electrodes in which the sulfur loading was 60% by weight, when sulfur filled micropores are not accessible for N2 molecules according to gas adsorption isotherm data. A limited contact of the confined sulfur with the electrolyte solution results in the highest reversible capacity and initial coulombic efficiency. This insight into the mechanism provides a new approach to the development of new electrolyte solutions and additives for Li-S cells.
The benefits of fluoroethylene carbonate (FEC)-based electrolyte solution (1 M LiPF6 in FEC/dimethyl carbonate (DMC)) over ethylene carbonate (EC)-based electrolyte solution (1 M LiPF6 in EC/DMC) for the cycling of sulfur/carbon (S/C) composite cathodes were demonstrated for S/C composites prepared with two drastically different types of carbon hosts, micrometer-sized activated carbon powder (AC1) and carbonized polyacrylonitrile (PAN) cloth. The formation of solid electrolyte interphase (SEI) on the surface of the cycled S/C electrodes was demonstrated using scanning electron microscopy (SEM) and energy-dispersive spectroscopy (EDS).
Ni-rich layered oxides and Li-rich layered oxides are topics of much research interest as cathodes for Li-ion batteries due to their low cost and higher discharge capacities compared to those of LiCoO2 and LiMn2O4. However, Ni-rich layered oxides have several pitfalls, including difficulty in synthesizing a well-ordered material with all Ni3+ ions, poor cyclability, moisture sensitivity, a thermal runaway reaction, and formation of a harmful surface layer caused by side reactions with the electrolyte. Recent efforts towards Ni-rich layered oxides have centered on optimizing the composition and processing conditions to obtain controlled bulk and surface compositions to overcome the capacity fade. Li-rich layered oxides also have negative aspects, including oxygen loss from the lattice during first charge, a large first cycle irreversible capacity loss, poor rate capability, side reactions with the electrolyte, low tap density, and voltage decay during extended cycling. Recent work on Li-rich layered oxides has focused on understanding the surface and bulk structures and eliminating the undesirable properties. Followed by a brief introduction, an account of recent developments on the understanding and performance gains of Ni-rich and Li-rich layered oxide cathodes is provided, along with future research directions.
The problem of corrosion of zinc in alkaline solutions has become a topic of considerable interest with the increasing use of zinc as the anode in a variety of alkaline batteries (primary alkaline zinc battery, secondary silver-zinc, and both primary and secondary zinc-air batteries), some of which contain great promise for propulsion of electric vehicles. Corrosion of pure and amalgamated zinc in pure concentrated KOH solutions was investigated using two methods: (a) galvanostatic measurements of the kinetics of hydrogen evolution with electrodic assessment of corrosion properties of the system and (b) volumetric measurement of the hydrogen evolution reflecting directly the rate of corrosion. The latter was followed as a function of time during 150 hr. It was found that the corrosion rate varies considerably with time and was suggested that different factors control the initial and the steady-state corrosion. The initial corrosion rate increases with increasing KOH concentration which is indicative of the chemical mechanism of hydrogen evolution. The change of the corrosion rate with time and the steady-state corrosion rate can be explained in terms of formation of an impermeable ZnO film at the surface.
SiOx-based materials attracted a great deal of attention as high-capacity Li(+) storage materials for lithium-ion batteries due to their high reversible capacity and good cycle performance. However, these materials still suffer from low initial Coulombic efficiency as well as high production cost, which are associated with the complicated synthesis process. Here, we propose a dual-size Si nanocrystal-embedded SiOx nanocomposite as a high-capacity Li(+) storage material prepared via cost-effective sol-gel reaction of triethoxysilane with commercially available Si nanoparticles. In the proposed nanocomposite, dual-size Si nanocrystals are incorporated into the amorphous SiOx matrix, providing a high capacity (1914 mAh g(-1)) with a notably improved initial efficiency (73.6%) and stable cycle performance over 100 cycles. The highly robust electrochemical and mechanical properties of the dual-size Si nanocrystal-embedded SiOx nanocomposite presented here are mainly attributed to its peculiar nanoarchitecture. This study represents one of the most promising routes for advancing SiOx-based Li(+) storage materials for practical use.
The effects of a solid electrolyte interface (SEI) additive, triacetoxyvinylsilane (VS), on the electrochemical performance of a lithium metal secondary battery were investigated. When 2 wt % VS was added to the electrolyte, no lithium dendrite on the lithium metal surface after precycling was observed and thereby the lowest interfacial resistance of the unit cell (LiCoO2/ Li) could be achieved. With these reasons, the capacity of the unit cell based on the electrolyte containing 2 wt % VS could maintain about 0% of the initial capacity after 200 cycles at a high charge/ discharge current density (C/2, 1.25 mA cm(-2)). (c) 2007 The Electrochemical Society.
Unlocking the full potential of rechargeable magnesium batteries has been partially hindered by the reliance on chloride-based complex systems. Despite the high anodic stability of these electrolytes, they are corrosive toward metallic battery components, which reduce their practical electrochemical window. Following on our new design concept involving boron cluster anions, monocarborane CB11 H12 (-) produced the first halogen-free, simple-type Mg salt that is compatible with Mg metal and displays an oxidative stability surpassing that of ether solvents. Owing to its inertness and non-corrosive nature, the Mg(CB11 H12 )2 /tetraglyme (MMC/G4) electrolyte system permits standardized methods of high-voltage cathode testing that uses a typical coin cell. This achievement is a turning point in the research and development of Mg electrolytes that has deep implications on realizing practical rechargeable Mg batteries.
© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Rechargeable magnesium batteries have lately received great attention for large-scale energy storage systems due to their high volumetric capacities, low materials cost, and safe characteristic. However, the bivalency of Mg2+ ions has made it challenging to find cathode materials operating at high voltages with decent (de)intercalation kinetics. In an effort to overcome this challenge, we adopt an unconventional approach of engaging crystal water in the layered structure of Birnessite MnO2 because the crystal water can effectively screen electrostatic interactions between Mg2+ ions and the host anions. The crucial role of the crystal water was revealed by directly visualizing its presence and dynamic rearrangement using scanning transmission electron microscopy (STEM). Moreover, the importance of lowering desolvation energy penalty at the cathode-electrolyte interface was elucidated by working with water containing non-aqueous electrolytes. In aqueous electrolytes, the decreased interfacial energy penalty by hydration of Mg2+ allows Birnessite MnO2 to achieve a large reversible capacity (231.1 mAh g-1) at high operating voltage (2.8 V vs. Mg/Mg2+) with excellent cycle life (62.5% retention after 10,000 cycles), unveiling the importance of effective charge shielding in the host and facile Mg2+ ions transfer through the cathode's interface.
Sodium ion batteries offer a potential alternative or complementary system to lithium ion batteries, which are widely used in many applications. For this purpose, layered O3-type NaCrO2 for use as a cathode material for sodium ion batteries was synthesized via an emulsion drying method. The produced NaCrO2 was modified by pitch as a carbon source and the products were tested in half and full cells using a NaPF6-based nonaqueous electrolyte solution. The carbon-coated NaCrO2 cathode material exhibits excellent capacity retention with superior rate capability up to 150 C-rate (99 mAh (g-oxide)-1), which corresponds to a full discharge during 27s. The surface conducting carbon layer plays a critically important role in the excellent performance of this cathode material. We confirmed the reaction process with sodium using X-ray diffraction and X-ray absorption spectroscopy. Thermal analysis using time-resolved X-ray diffraction also demonstrated the structural stability of the carbon-coated Na0.5CrO2. Due to the excellent performance of the cathode material described here, this work has the potential to promote accelerated development of sodium ion batteries for a large number of applications.
Lithium metal is considered the most promising anode for next-generation batteries due to its high energy density of 3840 mAhg-1. However, the extreme reactivity of the Li surface can induce parasitic reactions with solvents, contamination, and shuttled active species in the electrolyte, reducing performance of batteries employing Li metal anodes. One promising solution to this issue is application of thin chemical protection layers to the Li metal surface. Using a custom made ultrahigh vacuum (UHV) integrated deposition and characterization system, we demonstrate atomic layer deposition (ALD) of protection layers directly on Li metal with exquisite thickness control. We demonstrate as a proof of concept that a 14 nm thick, ALD Al2O3 layer can protect the Li surface from corrosion due to atmosphere, sulfur, and electrolyte exposure. Using Li-S battery cells as a test system, we demonstrate an improved capacity retention using ALD protected anodes over cells assembled with bare Li metal anodes for up to 100 cycles.
Hierarchically porous, metallic RuO2 hollow spheres are applied as a carbon-free cathode for Li–O2 batteries for the first time. They exhibit low charge potentials of ≈3.5 V, corresponding to overpotentials of 0.13/0.54 V in discharging and charging processes, a large reversible capacity of ≈1400 mAh g−1, and 100 cycles of full discharge and charge.
Lithium (Li) metal is the most ideal anode material in lithium ion batteries due to its large theoretical capacity (3860 mAh g-1) and low redox potential (-3.04 V vs. standard hydrogen potential, H2/H+). Nevertheless, surface dendrite formation during repeated charge-discharge cycles limits the cycle life and thus its practical use. The research efforts engaging polymer/ceramic coating or electrolyte additives have made noticeable progresses, but further improvement is still desirable. Here, we report significantly improved performance by a synergistic effect of multi-layered graphene (MLG) coating and Cs+ additive in the electrolyte. MLG separates solid-electrolyte-interphase (SEI) formation from Li dendrites and thus stabilizes Coulombic efficiency in each cycle. Cs ions facilitate efficient interlayer diffusion of Li ions by enlarging the interlayer distance of MLG, and also assists further for suppression of Li dendrite growth by electrostatic repulsion against Li ions. When paired with a stable sulfur-carbon composite electrode as a high capacity cathode, the Li-sulfur cell delivers an areal capacity of 4.0 mAh cm-2, the value comparable to those of current commercial lithium ion batteries, with 81.0% capacity retention after 200 cycles.
Delivery of high capacity with good retention is a challenge in developing cathodes for rechargeable sodium-ion batteries. Here we present a radially aligned hierarchical columnar structure in spherical particles with varied chemical composition from the inner end (Na[Ni0.75Co0.02Mn0.23]O2) to the outer end (Na[Ni0.58Co0.06Mn0.36]O2) of the structure. With this cathode material, we show that an electrochemical reaction based on Ni(2+/3+/4+) is readily available to deliver a discharge capacity of 157 mAh (g-oxide)(-1) (15 mA g(-1)), a capacity retention of 80% (125 mAh g(-1)) during 300 cycles in combination with a hard carbon anode, and a rate capability of 132.6 mAh g(-1) (1,500 mA g(-1), 10 C-rate). The cathode also exhibits good temperature performance even at -20°C. These results originate from rather unique chemistry of the cathode material, which enables the Ni redox reaction and minimizes the surface area contacting corrosive electrolyte.
Although lithium-oxygen batteries are attracting considerable attention because of potential for extremely high energy density, their practical use has been restricted due to a low energy efficiency and poor cycle life compared to lithium-ion batteries. Here we present a nanostructured cathode based on molybdenum carbide nanoparticles (Mo2C) dispersed on carbon nanotubes, which dramatically increase the electrical efficiency up to 88 % with a cycle life of more than 100 cycles. We found that the Mo2C nanoparticle catalysts contribute to the formation of a well-dispersed lithium peroxide nanolayers (Li2O2) on the Mo2C/carbon nanotubes with large contact area during oxygen reduction reaction (ORR). This Li2O2 structure can be decomposed at low potential upon oxygen evolution reaction (OER) by avoiding the energy loss associated with the decomposition of the typical Li2O2 discharge products.
Pairing lithium and oxygen in aprotic solvents can theoretically lead to one of the most promising electrochemical cells available. If successful, this system could compete with technologies such as the internal combustion engine and provide an energy density that can accommodate electric vehicle demands. However, there are many problems that have inhibited this technology from becoming realistic. One of the main reasons is capacity fading after only a few cycles, which is caused by the instability of electrolyte solutions in the presence of reduced oxygen species like O2.− and O22−. In recent years, using various analytical tools, researchers have been able to isolate the breakdown products arising from the reactions occurring between the aprotic solvent and the reduced oxygen species. Nevertheless, no solvents have yet been found that are fully stable throughout the reduction and oxidation processes. However, an understanding of these decomposition mechanisms can help us in designing new systems that are more stable toward the aggressive conditions taking place in LiO2 cell operation. This review will include analytical studies on the most widely used solvents in current LiO2 research.
The effect of mechanical surface modification on the performance of lithium (Li) metal foil electrodes is systematically investigated. The applied micro-needle surface treatment technique for Li metal has various advantages. 1) This economical and efficient technique is able to cover a wide range of surface area with a simple rolling process, which can be easily conducted. 2) This technique achieves improved rate capability and cycling stability, as well as a reduced interfacial resistance. The micro-needle treatment improves the rate capability by 20% (0.750 mAh at a rate of 7C) and increases the cycling stability by 200% (85% of the initial discharge capacity after 150 cycles) compared to untreated bare Li metal (0.626 mAh at a rate of 7C, 85% of the initial discharge capacity after only 70 cycles). 3) This technique efficiently suppresses Li formation of high surface area Li during the Li deposition process, as preferred sites for controlled Li plating are generated.
Li-O-2 batteries are attractive systems because they can deliver much higher energy densities than those of conventional lithium-ion batteries by engaging light gas-phase oxygen as a cathode active material. However, the inevitable generation of residual superoxide radicals gives rise to irreversible side reactions and consequently causes severe capacity degradation over cycling. To address this chronic issue, herein, we have taken a lesson from the human eye. Analogous to Li-O-2 batteries, the human eye is liable to attack by reactive oxygen species (ROS), from its lifetime exposure to sunlight. However, it protects itself from the ROS attack by using melanin as a radical scavenger. To mimic such a defense mechanism against radical attack, we included polydopamine (pD), which is one of the most common synthetic melanins, in the ether-based electrolyte. As an outcome of the superoxide radical scavenging by the pD additive, the irreversible side reaction products were alleviated significantly, resulting in superior cycling performance. The present investigation provides a message that simple treatments inspired by the human body or nature could be effective solutions to the problems in various energy devices.
Zinc-based batteries offer a safe, inexpensive alternative to fire-prone lithium-based batteries, but zinc-based batteries do not exhibit sufficient rechargeability—yet. Breaking through the centuries-old roadblock to zinc-based rechargeable batteries requires rethinking the electrode structure in order to control how zinc converts to zinc oxide during battery discharge and how the oxide is reversed back to metal upon recharging. We address the problems of inefficient zinc utilization and limited rechargeability by redesigning the zinc electrode as a porous, monolithic, three-dimensional (3D) aperiodic architecture. Utilization approaches 90% (728 mA h gZn−1) when the zinc “sponge” is used as the anode in a primary (single-use) zinc-air cell. To probe rechargeability of the 3D Zn sponge, we cycled Zn-vs.-Zn symmetric cells and Ag-Zn full cells under conditions that would otherwise support dendrite growth, and yet the Zn sponges remain dendrite-free after extensive cycling up to 188 mA h gZn−1. By using 3D-wired zinc architectures that innately suppress dendrite formation, all zinc-based chemistries can be reformulated for next-generation rechargeable batteries.
Indium thin films were evaluated as an anode material for Li-ion and Na-ion batteries (theoretical capacities
of 1012 mAh g�1 for Li and 467 mAh g�1 for Na). XRD data reveal that several known LieIn
phases (LiIn, Li3In2, LiIn2 and Li13In3) form providing 950 mAh g�1 reversible capacity. In contrast, the
reaction with Na is severely limited (75e125 mAh g�1). XRD data of short-circuited cells (40 h at 65 �C)
show the coexistence of NaIn, In, and an unknown NaxIn phase. In electrodes exhibit anomalous electrolyte
decomposition characterized by large discharge plateaus at 1.4 V vs Li/Liþ and 0.9 V vs Na/Naþ.
The presence of 5 wt% fluoroethylene carbonate additive suppresses the occurrence of the electrolyte
decomposition during the first cycle but does not necessarily prevent it upon further cycling. Prevention
of the anomalous decomposition can be achieved by restricting the (dis)charge voltages, increasing the
current or by using larger amounts of FEC. The native surface oxides (In2O3) are responsible for the
pronounced electrolyte decomposition during the first cycle while other In3þ species are responsible
during the subsequent cycles. We also show that indium electrodes can exhibit very high rate capability
for both Li (100 C-rate) and Na (30 C-rate)
The electrochemistry and the structural changes that occur during sodium insertion and removal from tin are studied by in-situ X-ray diffraction at 30 degrees C. The Sn vs. Na voltage curve has four distinct plateaus, corresponding to four two-phase regions during sodiation, and indicating that four Na-Sn binary alloys are formed. The alloy formed at full sodiation was found to be Na15Si4, as expected from the Na-Sn binary system at equilibrium. The three intermediate Na-Sn phases that form during sodiation have X-ray diffraction patterns that do not correspond to any known equilibrium phase of Na-Sn. More work is needed to characterize these new binary Na-Sn phases.
Systematic studies of the interactions between self-healing polymer and Si particles with particle size control leads to stable electrodes with high areal capacities of 3-4 mAh cm-2 for low-cost, large Si particles (0.5-1.5 μm in diameter).
The aprotic lithium-oxygen cell is based on the reversible reduction of oxygen on a cathode host to form lithium peroxide, and has received much attention in the last few years owing to its promise to offer increased electrochemical energy density beyond that provided by traditional Li-ion batteries. Carbon has been extensively utilized as a host, but it reacts with Li2O2 to form an insulating layer of lithium carbonate resulting in high overpotentials on charge. Establishing a stable, and conductive interface at the porous cathode is a major challenge that has motivated a search for non-carbonaceous cathode materials. Very few suitable materials have been discovered so far. Here we report on the synthesis of the metallic Magnéli phase Ti4O7 with a crystallite size between 10-20 nm, and show that a cathode fabricated from this material greatly reduces the overpotential compared to carbon. Oxidation of lithium peroxide on charge starts just above 3 V, comparable to gold and TiC, and the majority (~65%) of oxygen release occurs in the 3-3.5 V window vs Li+/Li as determined by on-line electrochemical mass spectrometry. Ti4O7 is much lighter and lower cost than gold, easy to prepare, and provides a controlled interface. X-ray photoelectron spectroscopy measurements show that a conductive, self-passivating substoichiometric metal oxide layer is formed at the surface which is important for stability.
Lithium/air is a fascinating energy storage system. The effective exploitation of air as a battery electrode has been the long-time dream of the battery community. Air is, in principle, a no-cost material characterized by a very high specific capacity value. In the particular case of the lithium/air system, energy levels approaching that of gasoline have been postulated. It is then not surprising that, in the course of the last decade, great attention has been devoted to this battery by various top academic and industrial laboratories worldwide. This intense investigation, however, has soon highlighted a series of issues that prevent a rapid development of the Li/air electrochemical system. Although several breakthroughs have been achieved recently, the question on whether this battery will have an effective economic and societal impact remains. In this review, a critical evaluation of the progress achieved so far is made, together with an attempt to propose future R&D trends. A forecast on whether Li/air may have a role in the next years' battery technology is also postulated.
The material's abundance is a simple and clear reason as to why sodium ions are attractive as charge carriers for rechargeable batteries. It is also expected that potassium ions have a further smaller desolvation energy compared with the Li and Na systems in aprotic solvents. However, further energy sacrifice is also unavoidable for the potassium system due to heavy atomic weight. In addition to the oxides, a wide variety of crystal structures is known for polyanionic compounds and the structural chemistry of the Na system is much more complicated in comparison to the Li system. Na ions are apparently coordinated by four fluoride ions at bottleneck sites when the Na ions migrate across the perovskite-type framework structure.
We report on layered NaTiO2 as a potential anode material for Na-ion batteries. The material is prepared from only earth-abundant elements, delivers 152 mAhg-1 of reversible capacity at C/10 rate, shows excellent cyclability with capacity retention over 98% after 60 cycles, and high rate capability. Furthermore, in situ X-ray diffraction analysis reveals a reversible O3-O’3 phase transition, including an unusual lattice parameter variation coupled to complicated Na vacancy orderings in a series of 2nd order phase transitions.
The development of high performance Si could have a considerable impact on our everyday lives and environment on the global scale. Despite the promising feature associated with the high specific capacity, commercialization of Si has been limited thus far due to its short cycle life. While a variety of Si nanostructures and composites have been demonstrated to resolve the aforementioned ruinous issues to large extents, the selection of polymeric binder has also turned out to play a critical role in the battery performance. Overall, binder plays a pivotal role in maintaining the structural integrity of electrode film and consequently the initial capacity, and the independent physical parameters of a polymer play a role in a combined manner. In particular, ion-dipole interactions between the key cell components, such as polymer-polymer, polymer-Si, and polymer-copper, are the core of the self-healing capability and give substantial tolerance to the electrode against large volume change of Si.