丁二腈增塑氟化聚碳酸酯基固态电解质用于4.5 V高压锂金属电池
Fluorinated polycarbonate-based solid electrolyte plasticized using succinonitrile for 4.5 V lithium metal batteries
孙锦旭 1王勇 1李瑀 2封伟3
作者信息
- 1. School of Materials Science and Engineering,Tianjin University,Tianjin 300072,China
- 2. School of Materials Science and Engineering,Tianjin University,Tianjin 300072,China;Institute of Advanced Technology and Equipment,Beijing University of Chemical Technology,Beijing 100029,China
- 3. School of Materials Science and Engineering,Tianjin University,Tianjin 300072,China;Key Laboratory of Advanced Ceramics and Machining Technology Ministry of Education,Tianjin 300072,China
- 折叠
摘要
与液态电解质相比,聚合物电解质(SPEs)具有更高的安全性,在储能领域具有广阔的应用前景.但是其高压下易分解、室温离子电导率低、室温循环性能差等问题阻碍了SPEs的应用.本研究以丙烯酸三氟乙酯和碳酸乙烯亚乙酯为原料,丁二腈为增塑剂,原位聚合制备了氟化聚碳酸酯基固态电解质SNSPE-40.SNSPE-40在25℃条件下离子电导率高达1.33 mS cm-1,电化学窗口达到5.4 V.得益于富含氟化锂的SEI层的形成,Li|SNSPE-40|Li电池以0.1 mA cm-2电流密度稳定循环了2000 h.在4.5 V截止电压和室温条件下,Li|SNSPE-40|LiNi0.9Co0.05-Mn0.05O2电池实现了0.5 C(1 C=220 mA g-1)倍率300圈的稳定循环(57.4％容量保持率).Li|SNSPE-40|LiCoO2电池实现了1 C(1 C=200 mA g-1)倍率250圈的长循环(54.9％容量保持率).这种新型固态电解质在高压固态锂金属电池中表现出巨大应用潜力.
Abstract
Solid polymer electrolytes(SPEs)are a great promising choice for energy storage owing to their enhanced safety compared to liquid electrolytes.However,challenges such as the decomposition under the high voltage,low room-temperature ionic conductivity and poor room-temperature cycling performance have hindered the practical application of SPEs.In this study,SNSPE-40,a novel fluorinated poly-carbonate-based electrolyte was prepared by the in-situ poly-merization of 2,2,2-trifluoroethyl acrylate and 4-vinyl-1,3-dioxolan-2-one;succinonitrile was added to the electrolyte as a plasticizer.Notably,SNSPE-40 exhibits a high ionic con-ductivity of 1.33 mS cm-1 and wide electrochemical window of 5.4 V(vs.Li/Li+)at 25℃.Due to the LiF-rich solid electrolyte interphase(SEI),the Li|SNSPE-40|Li symmetric cell remained stable for 2000 h at 0.1 mA cm-2.Finally,the Li|SNSPE-40|LiNi0.9Co0.05Mn0.05O2 cell,with a cut-off voltage of 4.5 V,dis-played good cycling stability at 0.5 C(1 C=220 mA g-1)and 26℃(57.4％capacity retention after 300 cycles).The Li|SNSPE-40|LiCoO2 cell displayed a long-cycling ability with a capacity retention of 54.9％for 250 cycles at 1 C(1 C=200 mA g-1)under the same voltage and temperature condi-tions.This new solid polymer electrolyte shows great potential for the application in high-voltage solid-state lithium metal batteries.
关键词
solid polymer electrolyte/fluorinated polycarbonate/succinonitrile/lithium metal batteries/solid electrolyte inter-phaseKey words
solid polymer electrolyte/fluorinated polycarbonate/succinonitrile/lithium metal batteries/solid electrolyte inter-phase引用本文复制引用
基金项目
National Key R&D Program of China(2022YFB3805702)
National Natural Science Foundation of China(52130303)
National Natural Science Foundation of China(52327802)
Jiangsu Key Laboratory of Electrochemical Energy Storage Technologies(EEST2021-4)
出版年
2024
NETL
NSTL
万方数据