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Advances and Prospects in Improving the Utilization Efficiency of Lithium for High Energy Density Lithium Batteries

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Advanced Functional Materials
Authors:
Jie Liu
Jie Liu
Yuhao Zhang
Yuhao Zhang
Yuhao Zhang
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Jinqiu Zhou
Jinqiu Zhou
Jinqiu Zhou
  • This person is not on ResearchGate, or hasn't claimed this research yet.
Wang Zhenkang at Soochow University (PRC)
Wang Zhenkang
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Abstract and Figures

Lithium‐ion batteries have attracted much attention in the field like portable devices and electronic vehicles. Due to growing demands of energy storage systems, lithium metal batteries with higher energy density are promising candidates to replace lithium‐ion batteries. However, using excess amounts of lithium can lower the energy density and cause safety risks. To solve these problems, it is crucial to use limited amount of lithium in lithium metal batteries to achieve higher utilization efficiency of lithium, higher energy density, and higher safety. The main reasons for the loss of active lithium are the side reactions between electrolyte and electrode, growth of lithium dendrites, and the volume change of electrode materials during the charge and discharge process. Based on these issues, much effort have been put to improve the utilization efficiency of lithium such as mitigating the side reactions, guiding the uniform lithium deposition, and increasing the adhesion between electrolyte and electrode. In this review, strategies for high utilization efficiency of lithium are presented. Moreover, the remaining challenges and the future perspectives on improving the utilization of lithium are also outlined.
Schematic of the strategies for the high utilization efficiency of lithium. 1) Electrolyte additives. Reproduced with permission.[¹⁷] Copyright 2019, Elsevier. 2) High concentrated electrolyte. Reproduced with permission.[¹⁹] Copyright 2017, Wiley‐VCH GmbH. 3) Extra lithium ion channel. Reproduced with permission.[²⁰] Copyright 2020, Wiley‐VCH GmbH. 4) Composite SEI. Reproduced with permission.[²¹] Copyright 2020, The Royal Society of Chemistry. 5) High specific area. Reproduced with permission.[²²] Copyright 2015, Springer Nature. 6) Enhanced wettability. Reproduced with permission.[²³] Copyright 2013, Wiley‐VCH GmbH. 7) Elimination of HF. Reproduced with permission.[²⁴] Copyright 2015, American Chemical Society. 8) Inhibition the dissolution of Mn. Reproduced with permission.[²⁵] Copyright 2015, Wiley‐VCH GmbH.
Schematic of the strategies for the high utilization efficiency of lithium. 1) Electrolyte additives. Reproduced with permission.[¹⁷] Copyright 2019, Elsevier. 2) High concentrated electrolyte. Reproduced with permission.[¹⁹] Copyright 2017, Wiley‐VCH GmbH. 3) Extra lithium ion channel. Reproduced with permission.[²⁰] Copyright 2020, Wiley‐VCH GmbH. 4) Composite SEI. Reproduced with permission.[²¹] Copyright 2020, The Royal Society of Chemistry. 5) High specific area. Reproduced with permission.[²²] Copyright 2015, Springer Nature. 6) Enhanced wettability. Reproduced with permission.[²³] Copyright 2013, Wiley‐VCH GmbH. 7) Elimination of HF. Reproduced with permission.[²⁴] Copyright 2015, American Chemical Society. 8) Inhibition the dissolution of Mn. Reproduced with permission.[²⁵] Copyright 2015, Wiley‐VCH GmbH.
… 
a) Coulombic efficiency of Cu||NMC cell cycled using 1 m LiPF6 FEC/TTE (3:7 v/v%) and 1 m LiPF6 in EC/DEC (1:1 v/v%) electrolytes. Reproduced with permission.[³²] Copyright 2020, Elsevier. b) Cycling performance of 1 m LiPF6 in FEC/TTE (3:7 v/v%) and 1 m LiPF6 in EC/DEC (1:1 v/v%). Reproduced with permission.[³²] Copyright 2020, Elsevier. c) Voltage profile of Li||Li symmetric cells with LiFSI + LiTFSI in DOL/DME electrolyte. Reproduced with permission.[³⁴] Copyright 2015, Elsevier. XPS analysis of the SEI layer. d) F 1s and e) Li 1s spectra of the SEI layer after lithium stripping on Cu substrate after 10 cycles. Reproduced with permission.[³⁸] Copyright 2018, Elsevier. f) Schematic of the synergistic effect of KPF6 and TMSP. Reproduced with permission.[¹⁷] Copyright 2019, Elsevier.
a) Coulombic efficiency of Cu||NMC cell cycled using 1 m LiPF6 FEC/TTE (3:7 v/v%) and 1 m LiPF6 in EC/DEC (1:1 v/v%) electrolytes. Reproduced with permission.[³²] Copyright 2020, Elsevier. b) Cycling performance of 1 m LiPF6 in FEC/TTE (3:7 v/v%) and 1 m LiPF6 in EC/DEC (1:1 v/v%). Reproduced with permission.[³²] Copyright 2020, Elsevier. c) Voltage profile of Li||Li symmetric cells with LiFSI + LiTFSI in DOL/DME electrolyte. Reproduced with permission.[³⁴] Copyright 2015, Elsevier. XPS analysis of the SEI layer. d) F 1s and e) Li 1s spectra of the SEI layer after lithium stripping on Cu substrate after 10 cycles. Reproduced with permission.[³⁸] Copyright 2018, Elsevier. f) Schematic of the synergistic effect of KPF6 and TMSP. Reproduced with permission.[¹⁷] Copyright 2019, Elsevier.
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a) Schematic of solution structures of dilute electrolyte and high concentration electrolyte. Reproduced with permission.[¹⁹] Copyright 2017, Wiley‐VCH GmbH. Voltage profiles for the cell cycle in c) 1 m LiFSI‐DME and d) 4 m LiFSI‐DME. Reproduced with permission.[³⁹] Copyright 2015, Springer Nature. d) Progression of Raman spectra with different salt concentrations in pure DMC and various DMC/BTFE mixtures. Reproduced with permission.[⁴¹] Copyright 2018, Wiley‐VCH GmbH. e) Electrochemical stability window of conventional electrolyte and localized high concentration electrolyte. Reproduced with permission.[⁴²] Copyright 2019, Springer Nature. f) Coulombic efficiency of conventional electrolyte and localized high concentration electrolyte. Reproduced with permission.[⁴²] Copyright 2019, Springer Nature.
a) Schematic of solution structures of dilute electrolyte and high concentration electrolyte. Reproduced with permission.[¹⁹] Copyright 2017, Wiley‐VCH GmbH. Voltage profiles for the cell cycle in c) 1 m LiFSI‐DME and d) 4 m LiFSI‐DME. Reproduced with permission.[³⁹] Copyright 2015, Springer Nature. d) Progression of Raman spectra with different salt concentrations in pure DMC and various DMC/BTFE mixtures. Reproduced with permission.[⁴¹] Copyright 2018, Wiley‐VCH GmbH. e) Electrochemical stability window of conventional electrolyte and localized high concentration electrolyte. Reproduced with permission.[⁴²] Copyright 2019, Springer Nature. f) Coulombic efficiency of conventional electrolyte and localized high concentration electrolyte. Reproduced with permission.[⁴²] Copyright 2019, Springer Nature.
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a) Coulombic efficiency of the NF‐LiFSI/DME and LiFSI/DME electrolyte at the current density of 3.0 mA cm⁻². Reproduced with permission.[⁴⁶] Copyright 2019, American Chemical Society. b) Symmetric cell cycling of the Li2S@Li, pristine Li, and Li2S8 preplant Li electrodes. Reproduced wtih permission.[⁴⁷] Copyright 20149, Wiley‐VCH GmbH. c) Voltage profiles of Li@MCMB‐F2||LiFePO4 full cells at 1st, 2nd, and 10th cycle. Reproduced with permission.[⁴⁸] Copyright 2020, Wiley‐VCH GmbH. d) The cycling performance of LiFePO4 full cells with different anodes. Reproduced with permission.[⁴⁸] Copyright 2020, Wiley‐VCH GmbH. e) The TEM image of the region containing both Li metal and its SEI. Reproduced with permission.[⁴⁹] Copyright 2020, Wiley‐VCH GmbH.
a) Coulombic efficiency of the NF‐LiFSI/DME and LiFSI/DME electrolyte at the current density of 3.0 mA cm⁻². Reproduced with permission.[⁴⁶] Copyright 2019, American Chemical Society. b) Symmetric cell cycling of the Li2S@Li, pristine Li, and Li2S8 preplant Li electrodes. Reproduced wtih permission.[⁴⁷] Copyright 20149, Wiley‐VCH GmbH. c) Voltage profiles of Li@MCMB‐F2||LiFePO4 full cells at 1st, 2nd, and 10th cycle. Reproduced with permission.[⁴⁸] Copyright 2020, Wiley‐VCH GmbH. d) The cycling performance of LiFePO4 full cells with different anodes. Reproduced with permission.[⁴⁸] Copyright 2020, Wiley‐VCH GmbH. e) The TEM image of the region containing both Li metal and its SEI. Reproduced with permission.[⁴⁹] Copyright 2020, Wiley‐VCH GmbH.
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a) ¹⁹F MAS NMR spectra of the SEI samples. Adapted with permission.[⁵³] Copyright 2019, American Chemical Society. b) Voltage profiles of Li and COF‐Li in a symmetrical cell with a current density of 1 mA cm⁻². Reproduced with permission.[²⁰] Copyright 2020, Wiley‐VCH GmbH. Top view SEM image of deposited lithium on c) the bare Li and e) LiF@Po–Li anodes. Reproduced with permission.[²¹] Copyright 2020, The Royal Society of Chemistry. Cross sectional SEM images of deposited Lithium on d) the bare Li and f) LiF@Po–Li anodes. Reproduced with permission.[²¹] Copyright 2020, The Royal Society of Chemistry. g) The relationship between the resistance of SEI layer and the cycle number. Reproduced with permission.[⁵⁵] Copyright 2017, Wiley‐VCH GmbH. h) Schematics of the lithium deposition on bare lithium and hybrid‐protected lithium by elastomer/LiPON. Reproduced with permission.[⁵⁶] Copyright 2017, American Chemical Society.
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a) ¹⁹F MAS NMR spectra of the SEI samples. Adapted with permission.[⁵³] Copyright 2019, American Chemical Society. b) Voltage profiles of Li and COF‐Li in a symmetrical cell with a current density of 1 mA cm⁻². Reproduced with permission.[²⁰] Copyright 2020, Wiley‐VCH GmbH. Top view SEM image of deposited lithium on c) the bare Li and e) LiF@Po–Li anodes. Reproduced with permission.[²¹] Copyright 2020, The Royal Society of Chemistry. Cross sectional SEM images of deposited Lithium on d) the bare Li and f) LiF@Po–Li anodes. Reproduced with permission.[²¹] Copyright 2020, The Royal Society of Chemistry. g) The relationship between the resistance of SEI layer and the cycle number. Reproduced with permission.[⁵⁵] Copyright 2017, Wiley‐VCH GmbH. h) Schematics of the lithium deposition on bare lithium and hybrid‐protected lithium by elastomer/LiPON. Reproduced with permission.[⁵⁶] Copyright 2017, American Chemical Society.
… 
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Advances and Prospects in Improving the Utilization
Efficiency of Lithium for High Energy Density Lithium
Batteries
Jie Liu, Yuhao Zhang, Jinqiu Zhou, Zhenkang Wang, Peng Zhu,* Yufeng Cao, Yiwei Zheng,
Xi Zhou, Chenglin Yan,* and Tao Qian*
Lithium-ion batteries have attracted much attention in the field like
portable devices and electronic vehicles. Due to growing demands of
energy storage systems, lithium metal batteries with higher energy density
are promising candidates to replace lithium-ion batteries. However, using
excess amounts of lithium can lower the energy density and cause safety
risks. To solve these problems, it is crucial to use limited amount of lithium
in lithium metal batteries to achieve higher utilization efficiency of lithium,
higher energy density, and higher safety. The main reasons for the loss of
active lithium are the side reactions between electrolyte and electrode, growth
of lithium dendrites, and the volume change of electrode materials during the
charge and discharge process. Based on these issues, much effort have been
put to improve the utilization efficiency of lithium such as mitigating the side
reactions, guiding the uniform lithium deposition, and increasing the adhesion
between electrolyte and electrode. In this review, strategies for high utilization
efficiency of lithium are presented. Moreover, the remaining challenges and the
future perspectives on improving the utilization of lithium are also outlined.
1. Introduction
Lithium ion batteries (LIBs), which were first commercialized in
the s, have attracted attention in the fields like portable de-
vices and electronic vehicles.[] The further development of LIBs
is limited by the low energy density due to intercalation chem-
istry of graphite anode in LIBs.[, ] To meet the growing demand
J. Liu, Y. Zhang, J. Zhou, Z. Wang, P. Zhu, Y. Cao, Y. Zheng, X. Zhou,
T. Qian
School of Chemistry and Chemical Engineering
Nantong University
Nantong , P. R. China
E-mail: pzhu@ntu.edu.cn; qiantao@ntu.edu.cn
Y. Zhang, Z. Wang, Y. Zheng, C. Yan
College of Energy
Key Laboratory of Core Technology of High Specific Energy Battery and
Key Materials for Petroleum and Chemical Industry
Soochow University
Suzhou , P. R. China
E-mail: c.yan@suda.edu.cn
C. Yan, T. Qian
Light Industry Institute of Electrochemical Power Sources
Suzhou , P. R. China
The ORCID identification number(s) for the author(s) of this article
can be found under https://doi.org/./adfm.
DOI: 10.1002/adfm.202302055
for energy storage, replacing the graphite
anode in lithium-ion batteries with lithium
metal is the promising strategy due to the
high specific capacity ( mA h g−)
and the lowest potential (−. V vs stan-
dard hydrogen electrode) of lithium.[] The-
oretically, the energy density of the bat-
teries with lithium metal anode is signifi-
cantly improved compared with LIBs. How-
ever, the research of lithium metal batteries
(LMBs) is still in the laboratory stage due
to some intrinsic problems of the LMBs.
The main reasons for the loss of lithium are
the growth of lithium dendrite during cy-
cling, the side reactions between electrolyte
and electrode, and the production of dead
lithium.[] In addition, using excess lithium
can increase the safety risks due to the high
reactivity of lithium and decrease the energy
density of LMBs. It is reported that when
using more than % excess lithium,
the volumetric energy density of LMBs
( mA h L−) is even lower than that of LIBs that use graphite
anode ( mA h L−).[] Therefore, decreasing the amount of
excess lithium to ensure the performance of LMBs and safety is
essential for the practical applications of high-eciency LMBs.
In LMBs, lithium ions are stripped from the cathode during
the charging process. The extracted lithium ions participate in
the side reactions with electrolytes when plated on the lithium
anode during the discharging process, which is responsible for
the main loss of lithium. Coulombic eciency (CE) is the ratio of
the amount of lithium stripped from the cathode compared with
the amount of plated lithium, providing the evaluation of the re-
versibility of the battery and utilization eciency of lithium.[]
In addition, CE can eectively predict the lifespan or capacity re-
tention of the practical LMBs. The capacity retention (CR) of the
LMBs can be calculated as the average CE to the power of cycle
number “n”,[] which can be expressed in the following equation:
CR =(averageCE)n()
Thus, an average CE of % is essential to meet the require-
ment for commercial use and ensure that negligible irreversible
loss of capacity of LMBs under practical application. For exam-
ple, to achieve the capacity retention of % after  cycles,
the average CE is at least .% according to equation. The
high CE is required especially in the LMBs with low amount
Adv. Funct. Mater. 2023,33,  ©  Wiley-VCH GmbH
2302055 (1 of 18)
... [1,2] However, the widespread adoption of LMBs is currently hampered by their limited cycle life and poor safety. [3,4] The uneven deposition of Li-ions (Li + ) during cycling promotes the uncontrolled growth of Li dendrites and the accumulation of dead Li. [5,6] Additionally, the inherent instability of the native solid electrolyte interphase (SEI) on the lithium metal anode (LMA) results in reduced DOI: 10.1002/adfm.202404945 ...
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... In lithium-metal batteries, wherein the redox reaction of lithium ions serves as an electrode reaction, a proper understanding of the solid electrolyte interphase (SEI) layer is essential [1][2][3][4]. This layer, which is formed on the surface of the lithium anode, is crucial for battery performance because it prevents the continuous decomposition of the electrolyte solution on the thermodynamically unstable lithium anode [5,6]. ...
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Understanding and modifications on lithium deposition in lithium metal batteries
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Lithium metal has been considered as an ultimate anode choice for next-generation secondary batteries due to its low density, superhigh theoretical specific capacity and the lowest voltage potential. Nevertheless, uncontrollable dendrite growth and consequently large volume change during stripping/plating cycles can cause unsatisfied operation efficiency and serious safety concern, restraining its commercial use for the last 40 years. As widely used lithium-ion battery is approaching its theoretical limit at present, it is increasingly urgent to develop new energy storage equipment with sufficient practical capacity. Herein, two important processes of lithium deposition, nucleation and growth on lithium metal anode are reviewed. Modified three-dimensional (3D) porous anodes with unique structure and dynamic surface conditions, as one of the most efficient designs on dendrites suppression, are specifically discussed in terms of their beneficial adjustment on the dendrite formation. Problems on current designs and prospects on future advanced porous anode are explored in the end.
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As the most hazardous side reaction, Li plating poses high risks of undermining electrochemical performance of Li-ion batteries by accelerating degradation. Under some extreme abuse conditions, Li plating can even jeopardize safety performance and induce catastrophic results like thermal runaway. Therefore, multiscale observation of Li plating is of great significance for understanding the internal mechanisms and early detection of Li plating. In this mini-review, the recent progress of formation mechanisms of plated metallic lithium was introduced. Then, the in situ and ex situ observation methods of macroscopic, microscopic and atomic level were summarized. Reference electrode provides a promising tool for real-time monitoring of anode potential, which is the critical factor of Li plating, showing great potentials in cloud-based battery management systems. Finally, some perspectives for future researches on Li plating observation and corresponding utilizations in developing Li plating free control strategies were proposed.
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Battery prelithiation enabled by lithium fixation on cathode
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Li3N in the form of powder as the most appealing sacrificial salt has already been investigated for prelithiation, yet not been widely acknowledged due to its incompatibility with common solvents to a great extent. Herein, we report an unexpected way by depositing metal lithium directly on cathode surface and then fixing it by nitrogen gas to synthesize pure alpha-Li3N film with (001) plane perpendicular to surface. Moreover, its decomposition pathway along the direction from the surface to the inner cathode is revealed. After being used to compensate the lithium loss in LiFePO4/graphite full cell, discharge capacity at 120th cycle has raised by 30.7% with 1% Li3N coating. Apart from that, this kind of Li3N film has successfully served as the sole lithium source to fabricate full-cell with TiS2 and graphite as electrodes, in which 142.4 mAh g⁻¹ of capacity can remain after 50 cycles. In short, the introducing/expelling of nitrogen for Li fixation/Li⁺ release is a facile strategy to realize battery prelithiation with easy preparation and high efficiency.
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Highly efficient lithium utilization in lithium metal full-cell by simulated missile guidance and confinement systems模拟导弹制导约束系统实现锂全电池中锂金属的 高效利用
Article
  • Nov 2020
The efficient utilization of metallic lithium (Li) is the key to enable application of Li metal full-cell with low amount of excess Li, contributing to higher safety and energy density. Herein, we report an extraordinary Li metal full-cell with only 20% excess Li, which demonstrated significantly improved reversibility and high Coulombic efficiency. Ingenious simulated missile guidance and confinement system (SMGCS) was designed to guide and confine Li deposition through constructing compatible silver lithiophilic sites and nitrate layer. Silver sites act as effective Li nuclei to attract Li ions and direct the initial nucleation. The generated nitrate layer affords an interfacial environment favorable for confined and uniform deep Li deposition, which is theoretically verified by molecular dynamics (MD) simulations. The two combined merits offer a robust and dendrite-free Li deposition, enabling the application of Li metal full-cell with slight excess Li. They also result in an outperformed Li cycling efficiency of ca. 99% for over 300 cycles along with deep cycling at a high capacity of 10 mA h cm−2 in carbonate electrolytes. The unprecedented high degree of Li utilization opens a new avenue for the future development of highly efficient Li metal full cells.
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