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Zhang Y, Lai H, Wu X, Wen Z. A Gel Polymer Electrolyte with High Uniform Na + Flux and its Constructed Hybrid Interface Synergistically to Facilitate High-Performance Sodium Batteries. SMALL METHODS 2024:e2400280. [PMID: 38973216 DOI: 10.1002/smtd.202400280] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/26/2024] [Revised: 06/01/2024] [Indexed: 07/09/2024]
Abstract
Sodium metal batteries (SMBs) can be developed on a large scale to achieve low-cost and high-capacity energy storage systems. Gel polymer electrolyte (GPE) can relieve volatilization of liquid electrolyte, adapt to volume changes in electrodes, and better satisfy the requirements of long-term SMBs. Herein, a dense polyurethane-based GPE modified with polyacrylonitrile is synthesized by rapidly swelling two-component polyurethane/polyacrylonitrile electrospun fiber film. Compared to traditional porous GPEs obtained by swelling porous matrixes, the fiber film provides uniform high Na+ flux inside GPE due to its partial solubility property and ability to dissociate salts. Therefore, it can reduce the polarization effect and induce uniform metal deposition under high current in conjunction with its constructed hybrid N/F-containing solid electrolyte interface (SEI) that possesses low ionic diffusion barrier. The study demonstrates that GPE has an ionic conductivity of 1.816 mS cm-1 at 20 °C and an ion transference number of 0.53. The full battery (NVP/GPE/Na) assembled with this GPE and Na3V2(PO4)3 (NVP) cathode shows 90.8% capacity retention rate after 1000 cycles at 10 C. Considering the convenient preparation and outstanding electrochemical performances of the obtained GPE, it can also be matched with other electrodes in the future to expand the application of sodium-based batteries.
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Affiliation(s)
- Yan Zhang
- State Key Lab of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai, 200050, P. R. China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, 100049, P. R. China
| | - Hongjian Lai
- State Key Lab of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai, 200050, P. R. China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, 100049, P. R. China
| | - Xiangwei Wu
- State Key Lab of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai, 200050, P. R. China
| | - Zhaoyin Wen
- State Key Lab of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai, 200050, P. R. China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, 100049, P. R. China
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Chen J, Yang Z, Xu X, Qiao Y, Zhou Z, Hao Z, Chen X, Liu Y, Wu X, Zhou X, Li L, Chou SL. Nonflammable Succinonitrile-Based Deep Eutectic Electrolyte for Intrinsically Safe High-Voltage Sodium-Ion Batteries. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2024; 36:e2400169. [PMID: 38607696 DOI: 10.1002/adma.202400169] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/04/2024] [Revised: 04/09/2024] [Indexed: 04/14/2024]
Abstract
Intrinsically safe sodium-ion batteries are considered as a promising candidate for large-scale energy storage systems. However, the high flammability of conventional electrolytes may pose serious safety threats and even explosions. Herein, a strategy of constructing a deep eutectic electrolyte is proposed to boost the safety and electrochemical performance of succinonitrile (SN)-based electrolyte. The strong hydrogen bond between S═O of 1,3,2-dioxathiolane-2,2-dioxide (DTD) and the α-H of SN endows the enhanced safety and compatibility of SN with Lewis bases. Meanwhile, the DTD participates in the inner Na+ sheath and weakens the coordination number of SN. The unique solvation configuration promotes the formation of robust gradient inorganic-rich electrode-electrolyte interphase, and merits stable cycling of half-cells in a wide temperature range, with a capacity retention of 82.8% after 800 cycles (25 °C) and 86.3% after 100 cycles (60 °C). Correspondingly, the full cells deliver tremendous improvement in cycling stability and rate performance.
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Affiliation(s)
- Jian Chen
- School of Environmental and Chemical Engineering, Shanghai University, Shanghai, 200444, China
- Institute for Carbon Neutralization, College of Chemistry and Materials Engineering, Wenzhou University, Zhejiang, 325035, China
| | - Zhuo Yang
- Institute for Carbon Neutralization, College of Chemistry and Materials Engineering, Wenzhou University, Zhejiang, 325035, China
- Wenzhou Key Laboratory of Sodium-Ion Batteries, Wenzhou University Technology Innovation Institute for Carbon Neutralization, Zhejiang, 325035, China
| | - Xu Xu
- Institute for Carbon Neutralization, College of Chemistry and Materials Engineering, Wenzhou University, Zhejiang, 325035, China
- Wenzhou Key Laboratory of Sodium-Ion Batteries, Wenzhou University Technology Innovation Institute for Carbon Neutralization, Zhejiang, 325035, China
| | - Yun Qiao
- School of Environmental and Chemical Engineering, Shanghai University, Shanghai, 200444, China
| | - Zhiming Zhou
- Institute for Carbon Neutralization, College of Chemistry and Materials Engineering, Wenzhou University, Zhejiang, 325035, China
- Wenzhou Key Laboratory of Sodium-Ion Batteries, Wenzhou University Technology Innovation Institute for Carbon Neutralization, Zhejiang, 325035, China
| | - Zhiqiang Hao
- Institute for Carbon Neutralization, College of Chemistry and Materials Engineering, Wenzhou University, Zhejiang, 325035, China
- Wenzhou Key Laboratory of Sodium-Ion Batteries, Wenzhou University Technology Innovation Institute for Carbon Neutralization, Zhejiang, 325035, China
| | - Xiaomin Chen
- Institute for Carbon Neutralization, College of Chemistry and Materials Engineering, Wenzhou University, Zhejiang, 325035, China
- Wenzhou Key Laboratory of Sodium-Ion Batteries, Wenzhou University Technology Innovation Institute for Carbon Neutralization, Zhejiang, 325035, China
| | - Yang Liu
- School of Environmental and Chemical Engineering, Shanghai University, Shanghai, 200444, China
- Institute for Carbon Neutralization, College of Chemistry and Materials Engineering, Wenzhou University, Zhejiang, 325035, China
| | - Xingqiao Wu
- Institute for Carbon Neutralization, College of Chemistry and Materials Engineering, Wenzhou University, Zhejiang, 325035, China
- Wenzhou Key Laboratory of Sodium-Ion Batteries, Wenzhou University Technology Innovation Institute for Carbon Neutralization, Zhejiang, 325035, China
| | - Xunzhu Zhou
- Institute for Carbon Neutralization, College of Chemistry and Materials Engineering, Wenzhou University, Zhejiang, 325035, China
- Wenzhou Key Laboratory of Sodium-Ion Batteries, Wenzhou University Technology Innovation Institute for Carbon Neutralization, Zhejiang, 325035, China
| | - Lin Li
- Institute for Carbon Neutralization, College of Chemistry and Materials Engineering, Wenzhou University, Zhejiang, 325035, China
- Wenzhou Key Laboratory of Sodium-Ion Batteries, Wenzhou University Technology Innovation Institute for Carbon Neutralization, Zhejiang, 325035, China
| | - Shu-Lei Chou
- Institute for Carbon Neutralization, College of Chemistry and Materials Engineering, Wenzhou University, Zhejiang, 325035, China
- Wenzhou Key Laboratory of Sodium-Ion Batteries, Wenzhou University Technology Innovation Institute for Carbon Neutralization, Zhejiang, 325035, China
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3
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Lin Y, Shang J, Liu Y, Wang Z, Bai Z, Ou X, Tang Y. Chlorination Design for Highly Stable Electrolyte toward High Mass Loading and Long Cycle Life Sodium-Based Dual-Ion Battery. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2024; 36:e2402702. [PMID: 38651672 DOI: 10.1002/adma.202402702] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2024] [Revised: 03/28/2024] [Indexed: 04/25/2024]
Abstract
Sodium-based dual ion batteries (SDIBs) have garnered significant attention as novel energy storage devices offering the advantages of high-voltage and low-cost. Nonetheless, conventional electrolytes exhibit low resistance to oxidation and poor compatibility with electrode materials, resulting in rapid battery failure. In this study, for the first time, a chlorination design of electrolytes for SDIB, is proposed. Using ethyl methyl carbonate (EMC) as a representative, chlorine (Cl)-substituted EMC not only demonstrates increased oxidative stability ascribed to the electron-withdrawing characteristics of chlorine atom, electrolyte compatibility with both the cathode and anode is also greatly improved by forming Cl-containing interface layers. Consequently, a discharge capacity of 104.6 mAh g-1 within a voltage range of 3.0-5.0 V is achieved for Na||graphite SDIB that employs a high graphite cathode mass loading of 5.0 mg cm-2, along with almost no capacity decay after 900 cycles. Notably, the Na||graphite SDIB can be revived for an additional 900 cycles through the replacement of a fresh Na anode. As the mass loading of graphite cathode increased to 10 mg cm-2, Na||graphite SDIB is still capable of sustaining over 700 times with ≈100% capacity retention. These results mark the best outcome among reported SDIBs. This study corroborates the effectiveness of chlorination design in developing high-voltage electrolytes and attaining enduring cycle stability of Na-based energy storage devices.
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Affiliation(s)
- Yuwei Lin
- Advanced Energy Storage Technology Research Center, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Jian Shang
- Advanced Energy Storage Technology Research Center, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, China
- Low-Dimensional Energy Materials Research Center, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, China
| | - Yuhua Liu
- Advanced Energy Storage Technology Research Center, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, China
- Nano Science and Technology Institute, University of Science and Technology of China, Suzhou, 215123, China
| | - Zelin Wang
- Advanced Energy Storage Technology Research Center, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, China
- Nano Science and Technology Institute, University of Science and Technology of China, Suzhou, 215123, China
| | - Zhengyang Bai
- Advanced Energy Storage Technology Research Center, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, China
- Nano Science and Technology Institute, University of Science and Technology of China, Suzhou, 215123, China
| | - Xuewu Ou
- Advanced Energy Storage Technology Research Center, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, China
| | - Yongbing Tang
- Advanced Energy Storage Technology Research Center, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
- Nano Science and Technology Institute, University of Science and Technology of China, Suzhou, 215123, China
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Ma X, Zhang D, Wen J, Fan L, Rao AM, Lu B. Sustainable Electrolytes: Design Principles and Recent Advances. Chemistry 2024; 30:e202400332. [PMID: 38654511 DOI: 10.1002/chem.202400332] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2024] [Revised: 04/23/2024] [Accepted: 04/23/2024] [Indexed: 04/26/2024]
Abstract
Today, rechargeable batteries are omnipresent and essential for our existence. In order to improve the electrochemical performance of electric fields, the introduction of electrolytes with fluorine (F)-based inorganic elemental compositions is a direction of exploration. However, most fluorocarbons have a high global warming potential and ozone depletion potential, which do not meet the sustainability requirements of the battery industry. Therefore, developing sustainable electrolytes is a viable option for future battery development. Although researchers have made much progress in electrolyte optimization, little attention has been paid to developing low-toxic and safe electrolytes. This review aims to elucidate the design principles and recent advances in this direction for solvents and salts. It concludes with a summary and outlook on future research directions for the molecular design of green electrolytes for practical high-voltage rechargeable batteries.
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Affiliation(s)
- Xuemei Ma
- School of Physics and Electronics, Hunan University, Changsha, 410082, P. R. China
| | - Dianwei Zhang
- School of Physics and Electronics, Hunan University, Changsha, 410082, P. R. China
| | - Jie Wen
- School of Physics and Electronics, Hunan University, Changsha, 410082, P. R. China
| | - Ling Fan
- School of Physics and Electronics, Hunan University, Changsha, 410082, P. R. China
| | - Apparao M Rao
- Department of Physics and Astronomy, Clemson Nanomaterials Institute, Clemson University, Clemson, SC, USA
| | - Bingan Lu
- School of Physics and Electronics, Hunan University, Changsha, 410082, P. R. China
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Wan S, Ma W, Wang Y, Xiao Y, Chen S. Electrolytes Design for Extending the Temperature Adaptability of Lithium-Ion Batteries: from Fundamentals to Strategies. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2024; 36:e2311912. [PMID: 38348797 DOI: 10.1002/adma.202311912] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/09/2023] [Revised: 01/16/2024] [Indexed: 02/25/2024]
Abstract
With the continuously growing demand for wide-range applications, lithium-ion batteries (LIBs) are increasingly required to work under conditions that deviate from room temperature (RT). However, commercial electrolytes exhibit low thermal stability at high temperatures (HT) and poor dynamic properties at low temperatures (LT), hindering the operation of LIBs under extreme conditions. The bottleneck restricting the practical applications of LIBs has promoted researchers to pay more attention to developing a series of innovative electrolytes. This review primarily covers the design of electrolytes for LIBs from a temperature adaptability perspective. First, the fundamentals of electrolytes concerning temperature, including donor number (DN), dielectric constant, viscosity, conductivity, ionic transport, and theoretical calculations are elaborated. Second, prototypical examples, such as lithium salts, solvent structures, additives, and interfacial layers in both liquid and solid electrolytes, are presented to explain how these factors can affect the electrochemical behavior of LIBs at high or low temperatures. Meanwhile, the principles and limitations of electrolyte design are discussed under the corresponding temperature conditions. Finally, a summary and outlook regarding electrolytes design to extend the temperature adaptability of LIBs are proposed.
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Affiliation(s)
- Shuang Wan
- State Key Laboratory of Chemical Resource Engineering, Beijing Key Laboratory of Electrochemical Process and Technology of Materials, Beijing University of Chemical Technology, Beijing, 10029, China
| | - Weiting Ma
- State Key Laboratory of Chemical Resource Engineering, Beijing Key Laboratory of Electrochemical Process and Technology of Materials, Beijing University of Chemical Technology, Beijing, 10029, China
| | - Yutong Wang
- Department of Chemistry, University College London, 20 Gordon Street, London, WC1H 0AJ, UK
| | - Ying Xiao
- State Key Laboratory of Chemical Resource Engineering, Beijing Key Laboratory of Electrochemical Process and Technology of Materials, Beijing University of Chemical Technology, Beijing, 10029, China
| | - Shimou Chen
- State Key Laboratory of Chemical Resource Engineering, Beijing Key Laboratory of Electrochemical Process and Technology of Materials, Beijing University of Chemical Technology, Beijing, 10029, China
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Guo X, Xie Z, Wang R, Luo J, Chen J, Guo S, Tang G, Shi Y, Chen W. Interface-Compatible Gel-Polymer Electrolyte Enabled by NaF-Solubility-Regulation toward All-Climate Solid-State Sodium Batteries. Angew Chem Int Ed Engl 2024; 63:e202402245. [PMID: 38462504 DOI: 10.1002/anie.202402245] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2024] [Revised: 02/28/2024] [Accepted: 03/04/2024] [Indexed: 03/12/2024]
Abstract
Gel-polymer electrolyte (GPE) is a pragmatic choice for high-safety sodium batteries but still plagued by interfacial compatibility with both cathode and anode simultaneously. Here, salt-in-polymer fibers with NaF salt inlaid in polylactide (PLA) fiber network was fabricated via electrospinning and subsequent in situ forming gel-polymer electrolyte in liquid electrolytes. The obtained PLA-NaF GPE achieves a high ion conductivity (2.50×10-3 S cm-1) and large Na+ transference number (0.75) at ambient temperature. Notably, the dissolution of NaF salt occupies solvents leading to concentrated-electrolyte environment, which facilitates aggregates with increased anionic coordination (anion/Na+ >1). Aggregates with higher HOMO realize the preferential oxidation on the cathode so that inorganic-rich and stable CEI covers cathode' surface, preventing particles' breakage and showing good compatibility with different cathodes (Na3V2(PO4)3, Na2+2xFe2-x(SO4)3, Na0.72Ni0.32Mn0.68O2, NaTi2(PO4)3). While, passivated Na anode induced by the lower LUMO of aggregates, and the lower surface tension between Na anode and PLA-NaF GPE interface, leading to the dendrites-free Na anode. As a result, the assembled Na || Na3V2(PO4)3 cells display excellent electrochemical performance at all-climate conditions.
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Affiliation(s)
- Xiaoniu Guo
- College of Chemistry, Zhengzhou University, Zhengzhou, 450001, Henan, P. R. China
| | - Zhengkun Xie
- College of Chemistry, Zhengzhou University, Zhengzhou, 450001, Henan, P. R. China
| | - Ruixue Wang
- College of Chemistry, Zhengzhou University, Zhengzhou, 450001, Henan, P. R. China
| | - Jun Luo
- College of Chemistry, Zhengzhou University, Zhengzhou, 450001, Henan, P. R. China
| | - Jiacheng Chen
- College of Chemistry, Zhengzhou University, Zhengzhou, 450001, Henan, P. R. China
| | - Shuai Guo
- College of Chemistry, Zhengzhou University, Zhengzhou, 450001, Henan, P. R. China
| | - Guochuan Tang
- College of Chemistry, Zhengzhou University, Zhengzhou, 450001, Henan, P. R. China
| | - Yu Shi
- Leeds Institute of Textiles and Colour (LITAC), School of Design, University of, Leeds, LS29JT, UK
| | - Weihua Chen
- College of Chemistry, Zhengzhou University, Zhengzhou, 450001, Henan, P. R. China
- State Key Laboratory of Structural Analysis, Optimization and CAE Software for Industrial Equipment, Zhengzhou University, Zhengzhou, 450002, Henan, P. R. China
- Yaoshan laboratory, Pingdingshan University, Pingdingshan Henan, 467000, P. R. China
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Wang X, Lu J, Wu Y, Zheng W, Zhang H, Bai T, Liu H, Li D, Ci L. Building Stable Anodes for High-Rate Na-Metal Batteries. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2024; 36:e2311256. [PMID: 38181436 DOI: 10.1002/adma.202311256] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2023] [Revised: 12/15/2023] [Indexed: 01/07/2024]
Abstract
Due to low cost and high energy density, sodium metal batteries (SMBs) have attracted growing interest, with great potential to power future electric vehicles (EVs) and mobile electronics, which require rapid charge/discharge capability. However, the development of high-rate SMBs has been impeded by the sluggish Na+ ion kinetics, particularly at the sodium metal anode (SMA). The high-rate operation severely threatens the SMA stability, due to the unstable solid-electrolyte interface (SEI), the Na dendrite growth, and large volume changes during Na plating-stripping cycles, leading to rapid electrochemical performance degradations. This review surveys key challenges faced by high-rate SMAs, and highlights representative stabilization strategies, including the general modification of SMB components (including the host, Na metal surface, electrolyte, separator, and cathode), and emerging solutions with the development of solid-state SMBs and liquid metal anodes; the working principle, performance, and application of these strategies are elaborated, to reduce the Na nucleation energy barriers and promote Na+ ion transfer kinetics for stable high-rate Na metal anodes. This review will inspire further efforts to stabilize SMAs and other metal (e.g., Li, K, Mg, Zn) anodes, promoting high-rate applications of high-energy metal batteries towards a more sustainable society.
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Affiliation(s)
- Xihao Wang
- School of Science, Harbin Institute of Technology (Shenzhen), Shenzhen, 518055, China
| | - Jingyu Lu
- School of Science, Harbin Institute of Technology (Shenzhen), Shenzhen, 518055, China
| | - Yehui Wu
- School of Science, Harbin Institute of Technology (Shenzhen), Shenzhen, 518055, China
| | - Weiran Zheng
- Guangdong Provincial Key Laboratory of Materials and Technologies for Energy Conversion, Guangdong Technion-Israel Institute of Technology, Shantou, 515063, China
- Department of Chemistry, Guangdong Technion-Israel Institute of Technology, Shantou, 515063, China
| | - Hongqiang Zhang
- State Key Laboratory of Advanced Welding and Joining, School of Materials Science and Engineering, Harbin Institute of Technology (Shenzhen), Shenzhen, 518055, China
| | - Tiansheng Bai
- State Key Laboratory of Advanced Welding and Joining, School of Materials Science and Engineering, Harbin Institute of Technology (Shenzhen), Shenzhen, 518055, China
| | - Hongbin Liu
- School of Electrical Engineering, Zhejiang University of Water Resources and Electric Power, Hangzhou, 310018, China
| | - Deping Li
- State Key Laboratory of Advanced Welding and Joining, School of Materials Science and Engineering, Harbin Institute of Technology (Shenzhen), Shenzhen, 518055, China
| | - Lijie Ci
- State Key Laboratory of Advanced Welding and Joining, School of Materials Science and Engineering, Harbin Institute of Technology (Shenzhen), Shenzhen, 518055, China
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Zhang S, Wu S, Hwang J, Matsumoto K, Hagiwara R. Unprotected Organic Cations─The Dilemma of Highly Li-Concentrated Ionic Liquid Electrolytes. J Am Chem Soc 2024; 146:8352-8361. [PMID: 38494762 DOI: 10.1021/jacs.3c14110] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/19/2024]
Abstract
Highly Li-concentrated electrolytes have been widely studied to harness their uniquely varying bulk and interface properties that arise from their distinctive physicochemical properties and coordination structures. Similar strategies have been applied in the realm of ionic liquid electrolytes to exploit their improved functionalities. Despite these prospects, the impact of organic cation behavior on interfacial processes remains largely underexplored compared to the widely studied anion behavior. The present study demonstrates that the weakened interactions between cations and anions engender "unprotected" organic cations in highly Li-concentrated ionic liquid electrolytes, leading to the decomposition of electrolytes during the initial charge. This decomposition behavior is manifested by the substantial irreversible capacities and inferior initial Coulombic efficiencies observed during the initial charging of graphite negative electrodes, resulting in considerable electrolyte consumption and diminished energy densities in full-cell configurations. The innate cation behavior is ascertained by examining the coordination environment of ionic liquid electrolytes with varied Li concentrations, where intricate ionic interactions between organic cations and anions are unveiled. In addition, anionic species with high Lewis basicity were introduced to reinforce the ionic interactions involving organic cations and improve the initial Coulombic efficiency. This study verifies the role of unprotected organic cations while highlighting the significance of the coordination environment in the performance of ionic liquid electrolytes.
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Affiliation(s)
- Shaoning Zhang
- Graduate School of Energy Science, Kyoto University, Yoshida-honmachi, Sakyo-ku, Kyoto 606-8501, Japan
| | - Shengan Wu
- Graduate School of Energy Science, Kyoto University, Yoshida-honmachi, Sakyo-ku, Kyoto 606-8501, Japan
| | - Jinkwang Hwang
- Graduate School of Energy Science, Kyoto University, Yoshida-honmachi, Sakyo-ku, Kyoto 606-8501, Japan
| | - Kazuhiko Matsumoto
- Graduate School of Energy Science, Kyoto University, Yoshida-honmachi, Sakyo-ku, Kyoto 606-8501, Japan
| | - Rika Hagiwara
- Graduate School of Energy Science, Kyoto University, Yoshida-honmachi, Sakyo-ku, Kyoto 606-8501, Japan
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