–C≡N functionalizing polycarbonate-based solid-state polymer electrolyte compatible to high-voltage cathodes  

作　　者：Shuo Ma Yanan Zhang Donghui Zhang Yating Zhang Wenbin Li Kemeng Ji Zhongli Tang Mingming Chen 

机构地区：[1]Key Laboratory for Green Chemical Technology of Ministry of Education,School of Chemical Engineering and Technology,Tianjin University,Tianjin 300350,China [2]Collaborative Innovation Center of Chemical Science and Engineering(Tianjin),Tianjin University,Tianjin 300350,China [3]The Research Center of Chemical Engineering,Tianjin University,Tianjin 300350,China

出　　处：《Journal of Energy Chemistry》2024年第11期422-431,共10页能源化学（英文版）

基　　金：National Natural Science Foundation of China (22078228)。

摘　　要：Solid-state polymer electrolytes(SPEs) capable of withstanding high voltage are considered to be key for next-generation energy storage devices with inherent safety as well as high energy density.This study involves the rational design of solid-state-C≡N functionalized P(VEC_1-CEA_(0.3))/LiTFSI@CE SPEs and its synthesis by in-situ free radical polymerization of vinyl ethylene carbonate(VEC) and 2-cyanoethyl acrylate(CEA).In situ polymerization yields electrode/electrolyte interfaces with low interfacial resistance,forming a stable SEI layer enriched with LiF,Li_(3)N,and RCOOLi,ensuring stable Li plating/stripping for over 1400 h.The-C≡N moiety renders the αH on the adjacent αC positively charged,thereby endowing it with the capability to anchor TFSI^(-).Simultaneously,the incorporation of-C≡N moiety diminishes the electron-donating ability of the C=O,C-O-C,and-C≡N functional groups,facilitating not only the ion conductivity enhancement but also a more rapid Li^(+)migration proved by DFT theoretical calculations and Raman spectroscopy.At room temperature,t_(Li+) of 0.60 for P(VEC_1-CEA_(0.3))/LiTFSI@CE SPEs is achieved when the ionic conductivity σ_(Li+)is 2.63×10^(-4) S cm^(-1) and the electrochemical window is expanded to5.0 V.Both coin cells with high-areal-loading cathodes and the 6.5-mAh pouch cell,exhibit stable charge/discharge cycling.At 25℃,the 4.45-V Li|P(VEC_1-CEA_(0.3))/LiTFSI@CE|LiCoO_(2) battery performs stable cycling over 200 cycles at 0.2 C,with a capacity retention of 82.1%.

关 键 词：Lithium-metal batteries HIGH-VOLTAGE Solid-state polymer electrolytes –C≡N In situ polymerization 

分 类 号：TM912[电气工程—电力电子与电力传动] O646[理学—物理化学]