LiNbO_(3)/PVDF双包覆LiCoO_(2)正极材料的制备及电性能研究  

Preparation of dual-layer LiNbO_(3)/PVDF coated LiCoO_(2) as cathode material for all-solid-state lithium-ion batteries and its electrochemical performance

作　　者：王晶良 WANG Jingliang(Hunan Shaoshan Yusheng Technology Co.,Ltd.,Xiangtan Hunan 411100,China)

机构地区：[1]湖南韶山钰盛科技有限责任公司,湖南湘潭411100

出　　处：《电源技术》2024年第12期2362-2367,共6页Chinese Journal of Power Sources

摘　　要：基于无机/高分子双层包覆策略,采用溶胶凝胶法、高温热处理和机械球磨在LiCoO_(2)(LCO)正极材料上依次修饰LiNbO_(3)(LNO)和聚偏氟乙烯(PVDF)保护层,制备LiNbO_(3)/PVDF双包覆的LCO正极材料(L/N/P)。结果表明,采用Li_(5.5)PS_(4.5)Cl_(1.5)为电解质,LiIn合金为负极,在0.1 C下正极材料L/N/P比容量为139.5 mAh/g,在0.5 C下循环500次后容量保持率为88.7%。研究为进一步提升全固态锂离子电池的容量和循环寿命,提供了新的思路。Based on rigid and flexible inorganic/polymer double coating strategy,using the sol-gel method,high-temperature heat treatment,and mechanical ball milling,LiNbO_(3)(LNO)and polyvinylidene fluoride(PVDF)protective layers were sequentially coated on LCO particles,and then LiNbO_(3)/PVDF double-coated LCO cathode material(L/N/P)was prepared.Its morphology,structure and electrochemical properties were investigated.The results show that LiNbO_(3)/PVDF double coating is successfully achieved without changing the morphology and crystal structure of LCO.Using Li_(5.5)PS_(4.5)Cl_(1.5) as the electrolyte and LiIn alloy as the negative electrode,the positive electrode material L/N/P delivers a specific capacity of 139.5 mAh/g at 0.1 C and a capacity retention of 88.7%after 500 cycles at 0.5 C.Electrochemical impedance spectroscopy(EIS)analysis results show that the L/N/P battery exhibits low interfacial impedance and charge transfer impedance before and after cycling,confirming its stability in Li5.5PS4.5Cl1.5 solid electrolyte.This work provides a new idea for stabilizing the oxide cathode/sulfide electrolyte interface and further improving the capacity and cycle life of allsolid-state lithium-ion batteries.

关 键 词：双层包覆 硫化物固态电解质 钴酸锂 全固态锂离子电池 

分 类 号：TM912[电气工程—电力电子与电力传动]