基于Li6.4La3Zr1.4Ta0.6O12/聚合物复合固态电解质的制备及电化学性能  

Preparation and Electrochemical Performance of LiLaZrTaO/Polymer-Based Solid Composite Electrolyte

作　　者：屠芳芳 谢健[2] 郭锋[1] 赵新兵[2] 王羽平 陈冬[1] 相佳媛[1] 陈建[1] TU Fang-Fang;XIE Jian;GUO Feng;ZHAO Xin-Bing;WANG Yu-Ping;CHEN Dong;XIANG Jia-Yuan;CHEN Jian(Zhejiang Narada Power Source Corporation Limited,Hangzhou 311100,China;School of Materials Science and Engineering,Zhejiang University,Hangzhou 310027,China)

机构地区：[1]浙江南都电源动力股份有限公司,杭州311100 [2]浙江大学材料科学与工程学院,杭州310027

出　　处：《无机化学学报》2020年第8期1515-1523,共9页Chinese Journal of Inorganic Chemistry

基　　金：中国博士后科学基金(No.2018M632508)资助项目。

摘　　要：采用溶液浇注法制备以Li6.4La3Zr1.4Ta0.6O12(LLZTO)为填料、聚氧化乙烯(PEO)与聚碳酸亚丙酯(PPC)共混的固态复合电解质膜,探讨了LLZTO含量和PPC/PEO比例对复合固态电解质离子电导率的影响。研究发现,当LLZTO含量为30%(w/w)及PPC/PEO质量比为1∶1时,固态复合电解质室温离子电导率最高,达到1.14×10-4S·cm-1。LLZTO和PPC的加入,降低了PEO基电解质的结晶性,提高了离子电导率、电化学稳定窗口(4.7 V)和锂离子迁移数(0.25),并改善了电解质与金属锂的化学稳定性。该固态复合电解质与LiFePO4/Li组装固态锂电池,室温下在0.1C循环70次后容量保持率82%,60℃下0.1C循环100次后容量保持率79%,0.5C和1C倍率下放电比容量仍能达到120.7和112.6 mAh·g-1。A solid composite electrolyte was prepared through a solution-casting method with polypropylene carbon-ate(PPC)and polyethylene oxide(PEO)as polymer blends,and Li6.4La3Zr1.4Ta0.6O12(LLZTO)particles as multifunc-tional fillers.The effects of LLZTO content and PPC/PEO mass ratio on the ionic conductivity of solid composite electrolyte were studied.Results show that the ionic conductivity at room temperature reached the highest value of1.14×10-4S·cm-1when LLZTO content was 30%(w/w)and the mass ratio of PPC to PEO was 1∶1.The incorporation of LLZTO and PPC into PEO repressed the crystallinity of polymer electrolyte,increased ionic conductivity,electro-chemical stability window(4.7 V)and Li+transference number(0.25),and reinforces interfacial stability between solid electrolyte and lithium anode.The capacity retention rates of the LiFePO4/Li cell with solid composite electro-lyte remain 82%after 70 cycles at room temperature and 79%after 100 cycles at 60℃.The discharge capacity reaches 120.7 and 112.6 mAh·g-1at 0.5C and 1C,respectively.

关 键 词：锂二次电池 固态无机-有机复合电解质 Li6.4La3Zr1.4Ta0.6O12 聚碳酸亚丙酯 共混聚合物 

分 类 号：TQ152[化学工程—电化学工业]