An entanglement association polymer electrolyte for Li-metal batteries

Hangchao Wang; Yali Yang; Chuan Gao; Tao Chen; Jin Song; Yuxuan Zuo; Qiu Fang; Tonghuan Yang; Wukun Xiao; Kun Zhang; Xuefeng Wang; Dingguo Xia

doi:10.1038/s41467-024-46883-8

An entanglement association polymer electrolyte for Li-metal batteries

Nat Commun. 2024 Mar 20;15(1):2500. doi: 10.1038/s41467-024-46883-8.

Authors

Hangchao Wang¹, Yali Yang¹, Chuan Gao¹, Tao Chen¹, Jin Song¹, Yuxuan Zuo¹, Qiu Fang², Tonghuan Yang¹, Wukun Xiao¹, Kun Zhang¹, Xuefeng Wang^{3

4

5}, Dingguo Xia^{6

7}

Affiliations

¹ Beijing Key Laboratory of Theory and Technology for Advanced Batteries Materials, School of Materials Science and Engineering, Peking University, Beijing, 100871, China.
² Institute of carbon neutrality, Peking University, Beijing, 100871, China.
³ Institute of carbon neutrality, Peking University, Beijing, 100871, China. wxf@iphy.ac.cn.
⁴ Laboratory for Advanced Materials & Electron Microscopy, Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China. wxf@iphy.ac.cn.
⁵ College of Materials Science and Opto-Electronic Technology, University of Chinese Academy of Sciences, Beijing, 100049, China. wxf@iphy.ac.cn.
⁶ Beijing Key Laboratory of Theory and Technology for Advanced Batteries Materials, School of Materials Science and Engineering, Peking University, Beijing, 100871, China. dgxia@pku.edu.cn.
⁷ Institute of carbon neutrality, Peking University, Beijing, 100871, China. dgxia@pku.edu.cn.

Abstract

To improve the interface stability between Li-rich Mn-based oxide cathodes and electrolytes, it is necessary to develop new polymer electrolytes. Here, we report an entanglement association polymer electrolyte (PVFH-PVCA) based on a poly (vinylidene fluoride-co-hexafluoropropylene) (PVFH) matrix and a copolymer stabilizer (PVCA) prepared from acrylonitrile, maleic anhydride, and vinylene carbonate. The entangled structure of the PVFH-PVCA electrolyte imparts excellent mechanical properties and eliminates the stress arising from dendrite growth during cycling and forms a stable interface layer, enabling Li//Li symmetric cells to cycle steadily for more than 4500 h at 8 mA cm^-2. The PVCA acts as a stabilizer to promote the formation of an electrochemically robust cathode-electrolyte interphase. It delivers a high specific capacity and excellent cycling stability with 84.7% capacity retention after 400 cycles. Li_1.2Mn_0.56Ni_0.16Co_0.08O₂/PVFH-PVCA/Li full cell achieved 125 cycles at 1 C (4.8 V cut-off) with a stable discharge capacity of ~2.5 mAh cm^-2.

Abstract

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