Reduction-Tolerance Electrolyte Design for High-Energy Lithium Batteries

Chuangchao Sun; Ruhong Li; Suting Weng; Chunnan Zhu; Long Chen; Sen Jiang; Long Li; Xuezhang Xiao; Chengwu Liu; Lixin Chen; Tao Deng; Xuefeng Wang; Xiulin Fan

doi:10.1002/anie.202400761

Reduction-Tolerance Electrolyte Design for High-Energy Lithium Batteries

Angew Chem Int Ed Engl. 2024 May 6;63(19):e202400761. doi: 10.1002/anie.202400761. Epub 2024 Apr 4.

Authors

Chuangchao Sun¹, Ruhong Li^{1

2}, Suting Weng³, Chunnan Zhu¹, Long Chen^{1

4}, Sen Jiang^{1

2}, Long Li¹, Xuezhang Xiao¹, Chengwu Liu⁵, Lixin Chen^{1

6}, Tao Deng⁷, Xuefeng Wang³, Xiulin Fan¹

Affiliations

¹ State Key Laboratory of Silicon and Advanced Semiconductor Materials, School of Materials Science and Engineering, Zhejiang University, Hangzhou, 310027, China.
² ZJU-Hangzhou Global Scientific and Technological Innovation Center, Zhejiang University, Hangzhou, 311215, China.
³ Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China.
⁴ Polytechnic Institute, Zhejiang University, Hangzhou, 310027, China.
⁵ Department of Chemical Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China.
⁶ Key Laboratory of Advanced Materials and Applications for Batteries of Zhejiang Province, Hangzhou, 310013, China.
⁷ China-UK Low Carbon College, Shanghai Jiao Tong University, Shanghai, 201306, China.

PMID: 38497902
DOI: 10.1002/anie.202400761

Abstract

Lithium batteries employing Li or silicon (Si) anodes hold promise for the next-generation energy storage systems. However, their cycling behavior encounters rapid capacity degradation due to the vulnerability of solid electrolyte interphases (SEIs). Though anion-derived SEIs mitigate this degradation, the unavoidable reduction of solvents introduces heterogeneity to SEIs, leading to fractures during cycling. Here, we elucidate how the reductive stability of solvents, dominated by the electrophilicity (EPT) and coordination ability (CDA), delineates the SEI formed on Li or Si anodes. Solvents exhibiting lower EPT and CDA demonstrate enhanced tolerance to reduction, resulting in inorganic-rich SEIs with homogeneity. Guided by these criteria, we synthesized three promising solvents tailored for Li or Si anodes. The decomposition of these solvents is dictated by their EPTs under similar solvation structures, imparting distinct characteristics to SEIs and impacting battery performance. The optimized electrolyte, 1 M lithium bis(fluorosulfonyl)imide (LiFSI) in N-Pyrrolidine-trifluoromethanesulfonamide (TFSPY), achieves 600 cycles of Si anodes with a capacity retention of 81 % (1910 mAh g^-1). In anode-free Cu||LiNi_0.5Co_0.2Mn_0.3O₂ (NCM523) pouch cells, this electrolyte sustains over 100 cycles with an 82 % capacity retention. These findings illustrate that reducing solvent decomposition benefits SEI formation, offering valuable insights for the designing electrolytes in high-energy lithium batteries.

Keywords: Electrolyte Design; High-Energy Lithium Batteries; Homogeneity; Reduction-Tolerance; Solid Electrolyte Interphases.