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Free-energy-composition diagrams for (a) ideal solution, (b) and (c) regular solutions, and (d) incomplete solid solution.
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![Table 3 . Electrochemical data for spinel cathode materials. [50]](profile/Gao-Jian-11/publication/291389311/figure/tbl1/AS:668584523100160@1536414380008/Electrochemical-data-for-spinel-cathode-materials-50_Q320.jpg)
The physical fundamentals and influences upon electrode materials' open-circuit voltage (OCV) and the spatial distribution of electrochemical potential in the full cell are briefly reviewed. We hope to illustrate that a better understanding of these scientific problems can help to develop and design high voltage cathodes and interfaces with low Ohm...
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... It has been deliberated for both of the voltage approximation approaches, i.e. Fermi and internal energy 24,45,46 . Regarding the relation of DOS values and capacity, correspondence of the reacting electrons with the reacting component (e.g. ...
... So far, voltage-profile has been calculated/estimated by combining thermodynamics with kinetics concepts using various approaches 19,45,[86][87][88] . Subsequently, as a matter of fact, this paper is an attempt to extend the border of the modern thermodynamics toward kinetics' territories; since, it implements pure concepts of modern physics to estimate the voltage-profile (a macroscopic measurable characterization). ...
This study evaluates electrochemical voltage-range and voltage-profile regarding electrodes of insertion (intercalation) batteries. The phrase “voltage-range” expresses the difference between obtained maximum and minimum potential for the cells. It also can be called as operating voltage-range, working voltage-range, electrochemical voltage-range, or voltage window. This paper proposes a new notion regarding electron density of states, i.e. trans-band, which can be implemented to justify the voltage -range and -profile, by means of Fermi levels’ alignment. Voltage -range and -profile of a number of insertion electrode materials are clarified by the proposed theoretical approach, namely LiMn2O4, Li2Mn2O4, ZnMn2O4, LiFePO4, LiCoO2, Li2FeSiO4, LiFeSO4F, and TiS2. Moreover, the probable observed difference between charge and discharge profile is explained by the approach. The theoretical model/approach represents a number of important concepts, which can meet some scientific fields, e.g. electrochemistry, energy storage devices, solid state physics (DFT), and phase diagrams. By means of DFT calculations, this paper deals with quantizing the energy of electrochemical reactions, justifying the configuration of voltage-profile, and explaining the origin of the voltage-range. Accordance with the experimental observations suggests that this paper can extend boundary of quantum mechanics toward territories of classical thermodynamics, and boundary of the modern thermodynamics toward kinetics. Opening a new horizon in the related fields, this paper can help tuning, engineering, and predicting cell-voltage behavior.
... Once an appropriate battery model is established, the charging optimization can be conducted for the key performance indexes of the battery. Electrochemical models study the complex chemical reactions inside batteries [25,26]. It can characterize the battery in detail, but the model is somewhat complex. ...
... Update and according to (25). ...
... The open circuit voltage (OCV) of the cell is the difference between the Fermi energy level of CNTS and oxidation potential of Zinc electrode. [25] CNTS/Zn Pouch Cell Fabrication: ...
Aqueous zinc-ion batteries are one of the most efficient and promising energy storage devices due to immense amount advantages such as non-toxicity, safety, cost-effectiveness, and earth abundance. However, zinc metal has the redox potential of -0.76V which is comparable and suitable for aqueous systems as an anode. Herein, quaternary chalcogenide wurtzite Cu 2 NiSnS 4 (CNTS) has been demonstrated as a stable electrode material for aqueous Zinc-ion battery pouch cell with high capacity and the potential of 1.34V. The band alignment of the Zn/CNTS also has been studied by the combined comparison of the optical band gap of CNTS and cyclic voltammetry curve analysis. CNTS delivers the specific capacity of 261mAh/g at the current density of 62.5mAh/g and good cycle performance in Zn/CNTS pouch cells. The striking electrochemical properties are ascribed to the excellent stability of CNTS while galvanostatic cycling, in which the cation Zn ²⁺ can be intercalated/deintercalated at the chalcogenide cathode CNTS. The intercalation results in the formation of ZnS while cycling which has been analyzed by Raman spectra after the cycling of pouch cell. The mechanism study discloses the reversible shuttling of Zn ²⁺ cations into/from CNTS.
... The lithium battery was discovered in 1912 by Gilbert N. Lewis [74]. Lithium is the lightest metal [75], with a high electrochemical potential and an interesting specific energy per weight [76,77]. In the early 1970s, the first non-rechargeable lithium-metal batteries (LMB) became commercially available. ...
Battery technologies have recently undergone significant advancements in design and manufacturing to meet the performance requirements of a wide range of applications, including electromobility and stationary domains. For e-mobility, batteries are essential components in various types of electric vehicles (EVs), including battery electric vehicles (BEVs), plug-in hybrid electric vehicles (PHEVs), and fuel cell electric vehicles (FCEVs). These EVs rely on diverse charging systems, including conventional charging, fast-charging, and vehicle-to-everything (V2X) systems. In stationary applications, batteries are increasingly being employed for the electrical management of micro/smart grids as transient buffer energy storage. Batteries are commonly used in conjunction with power electronic interfaces to adapt to the specific requirements of various applications. Furthermore, power electronic interfaces to batteries themselves have evolved technologically, resulting in more efficient, thermally efficient, compact, and robust power converter architectures. This article offers a comprehensive review of new-generation battery technologies. The topic is approached from the perspective of applications, emerging trends, and future directions. The article explores new battery technologies utilizing innovative electrode and electrolyte materials, their application domains, and technological limitations. In conclusion, a discussion and analysis are provided, synthesizing the technological evolution of batteries while highlighting new trends, directions, and prospects.
... The inevitable battery energy drop at high power is partly related to the ohmic drop phenomena since ohmic drop effects increase for high currents or powers, as detailed in the following. For an electrochemical system made up of a sandwich of conductive, ionic, or electronic materials, the voltage between the terminals can be split into two different types of terms: interfacial and volume potential differences [12,13], as shown in Equation (1): The interfacial terms consist of two parts: -A part that does not depend on the current, frequently called open circuit voltage OCV; -A part that strongly depends on the level of current flowing through the cell and which is mainly located at the positive and negative interfaces, usually called overpotentials or polarizations: ...
In this study, we investigate the use of the ohmic drop compensation method during
battery discharges at different rates. Four different types of NMC Li-ion batteries are compared
and three 18,650 cells of each type are tested to evaluate the performance dispersion. The cell type
that shows significant performance improvement thanks to ohmic drop compensation in this first
experimental part is then selected to complete the exploration. A drone-type usage profile is set
up and demonstrates without any doubt the interest of using this type of protocol in such usage.
Finally, a preliminary aging study is also performed on this type of cells: ohmic drop compensation
use has no effect on low-power performance decrease during aging and has a moderate impact on
high-power performances.
... In addition to lithium-ion batteries, several other types of batteries, such as those using sodium (Na + ), potassium (K + ), magnesium (Mg 2+ ), aluminum (Al 3+ ), and zinc (Zn 2+ ) ions, use the same energy storage mechanism [139]. However, developing innovative anode materials for lithium-ion batteries is essential because the capacity of graphite anodes is limited, and they are unable to keep pace with the increasing demand for energy storage [140]. The search for future anode materials centers around MXene materials [56,57,138]. ...
Two-dimensional niobium carbide (Nb2C), a member of the emerging MXene family, has recently garnered attention in various fields, including materials science, physics, chemistry, and nanotechnology. In this review, we highlight the material properties, synthesis strategies, and applications of Nb2C in energy storage devices, catalysis, and photovoltaic devices. We first introduce the synthesis methods, structural characteristics, and notable chemical and physical properties. Then, we discuss the influence of morphology, functional groups, and electrolytes on electrochemical energy storage devices, and present and compare advancements of various Nb2C-based batteries and supercapacitors. Next, we summarize the current progress of Nb2C MXene in electrocatalytic and photocatalytic hydrogen evolution reactions. Finally, we present the implementation of Nb2C MXene as a charge transport layer in organic and perovskite solar cells. These examples encompass diverse architectures, interface configurations, and functionalization approaches, showing a promising future for Nb2C as a rising energy material. They also inspire researchers to come up with innovative material designs to improve device performance and extend possible applications of Nb2C MXene.
... 13,22,37 During Mn reduction, lithium must be inserted into one of the tetragonal 4a, 4b, 8e, or 16g sites. 38,39 The exact location, however, is still unclear for the ordered high voltage spinel. ...
... The S-shaped profile of the step indicates the presence of either a solid solution or that there are more than two phases involved in the reaction. 38,46 A homogeneous transformation of one solid solution phase is not supported by the large voltage drop that is observed in the galvanostatic profile. Consequently, the defined voltage step suggests the presence of another phase with tetragonal symmetry I4 1 amd with smaller a, b (a, b < 5.740) and larger c parameter (c > 8.630 Å), namely T2. ...
High voltage spinel is one of the most promising next-generation cobalt-free cathode materials for lithium ion battery applications. Besides the typically utilized compositional range of LixNi0.5Mn1.5O4 0 < x < 1 in the voltage window of 4.90-3.00 V, additional 1.5 mol of Li per formula unit can be introduced into the structure, in an extended voltage range to 1.50 V. Theoretically, this leads to significant increase of the specific energy from 690 to 1190 Wh/kg. However, utilization of the extended potential window leads to rapid capacity fading and voltage polarization that lack a comprehensive explanation. In this work, we conducted potentiostatic entropymetry, operando XRD and neutron diffraction on the ordered stoichiometric spinel LixNi0.5Mn1.5O4 within 0 < x < 2.5 in order to understand the dynamic structure evolution and correlate it with the voltage profile. During the two-phase reaction from cubic (x < 1) to tetragonal (x > 1) phase at ∼2.8 V, we identified the evolution of a second tetragonal phase with x > 2. The structural evaluation during the delithiation indicates the formation of an intermediate phase with cubic symmetry at a lithium content of x = 1.5. Evaluation of neutron diffraction data, with maximum entropy method, of the highly lithiated phase LixNi0.5Mn1.5O4 with 2 < x < 2.5 strongly suggests that lithium ions are located on octahedral 8a and tetrahedral 4a positions of the distorted tetragonal phase I41amd. Consequently, we were able to provide a conclusive explanation for the additional voltage step at 2.10 V, the sloping voltage profile below 1.80 V, and the additional voltage step at ∼3.80 V.
... Since the energy per unit mass or volume of electrochemical systems are primarily governed by the voltage output, V as well as quantity of electrons charge per unit mass or volume, Q as shown in equation (1) or alternatively represented by equation (2), increasing the redox potential between electrodes and enriching the electrodes with lithium content will effectively improve the energy density [20]. The focal point of this article is to holistically review the synthesis methodology of lithium cobalt manganese tetroxide (LiCoMnO4) that display high reduction potential to elevate the voltage output of lithium-ion batteries. ...
... The chemical reaction in secondary cells used in rechargeable batteries on the other hand are reversible as electric current were applied to the device and regenerates the original chemical reactants, allowing the device to be repetitively discharged and recharged for a finite cycle [17]. Rechargeable batteries designed for high voltage output and energy density such as lithium-ion electrochemical system shall ideally be constructed of anode materials that exhibit low oxidation potential, Eoxidation and paired with cathode compounds that possess high reduction potential, Ereduction relative to lithium metal [20,25]. Oxidation will take place on the anode, while reduction will occur on the cathode during discharge and vice versa during charging cycle. ...
Spinel structured lithium cobalt manganese tetroxide (LiCoMnO4) which exhibit unrivalled reduction potential of 5.3V (vs. Li0 | Li+) was identified to be one of the potential cathode candidates for next generation lithium-ion batteries offering high voltage output and energy density. The focal point of this article is to holistically review relevant techniques established for the synthesis of LiCoMnO4 compound, particularly solid-state reaction, sol-gel synthesis, flux method and hydrothermal technology. Electrochemical performances of lithium cobalt manganese tetroxide (LiCoMnO4) synthesised via the four distinctive approaches as well as the critical process parameters will be compared and scrutinised. Adversities associated with deoxygenation in the course of synthesis process at high temperature and proposed countermeasure via fluorine-substitution will also be discussed.
... The opposite is true during charging. [17][18][19][20] The electrochemical potentials of the electrode materials are a significant contributing component and can aid in the design and development of appropriate intercalation materials to produce batteries with a high energy density. In terms of several electrochemical characteristics, such as battery voltage, specific capacity, specific energy, specific power, energy density, coulombic efficiency, etc, the performance of a LiB can be assessed. ...
... For a typical battery working at normal charging rates (<2C), the external electric field is mainly applied to the solid−liquid interface for a reversible electrochemical reaction and the applied electric field on the bulk electrolyte for migration is generally negligible, resulting in an ignorable migration term, as well. 14 To simplify the analysis of liquid transport, we limited the discussion about liquid transport to situations under normal charge rates. Therefore, liquid diffusion (second term) dominates Li-ion transport in the electrolyte. ...
Rate capability is characterized necessarily in almost all battery-related reports, while there is no universal metric for quantitative comparison. Here, we proposed the characteristic time of diffusion, which mainly combines the effects of diffusion coefficients and geometric sizes, as an easy-to-use figure of merit (FOM) to standardize the comparison of fast-charging battery materials. It offers an indicator to rank the rate capabilities of different battery materials and suggests two general methods to improve the rate capability: decreasing the geometric sizes or increasing the diffusion coefficients. Based on this FOM, more comprehensive FOMs for quantifying the rate capabilities of battery materials are expected by incorporating other processes (interfacial reaction, migration) into the current diffusion-dominated electrochemical model. Combined with Peukert's empirical law, it may characterize rate capabilities of batteries in the future.
