PEO/PPC基复合固态电解质的制备及性能  

Preparation and performance of PEO/PPC-based composite solid electrolyte

作　　者：陈绍敏 付微婷 杨泽林 王庆杰 CHEN Shao-min;FU Wei-ting;YANG Ze-lin;WANG Qing-jie(State Key Laboratory of Advanced Chemical Power Sources,Guizhou Meiling Power Sources Co.,Ltd.,Zunyi,Guizhou 563003,China)

机构地区：[1]贵州梅岭电源有限公司,特种化学电源国家重点实验室,贵州遵义563003

出　　处：《电池》2023年第3期303-307,共5页Battery Bimonthly

基　　金：贵州省科技计划项目(黔科合成果[2021]一般104)。

摘　　要：聚环氧乙烷(PEO)聚合物基固态电解质(SPE)具有较好的黏弹性和成膜性,但电化学窗口低、离子电导率低、厚度高、强度差和锂负极不稳定性等,阻碍了其应用。以5μm基膜为支撑材料,通过聚碳酸丙烯酯(PPC)的增塑,制备一种适用于高电压钴酸锂(LCO)电池且具有良好界面相容性的PEO/PPC基复合固态电解质(CPE)。该电解质在室温下的电化学性能较好:电压窗口可达0~4.5 V、离子电导率高达4.32×10^(-4)S/cm、Li^(+)迁移数高达0.508。Li|CPE|Li对称电池在常温、0.2 mA/cm^(2)下,可稳定循环超过900 h。基于CPE的电池具有较好的循环稳定性,以0.1 C在3.0~4.4 V循环60次,容量保持率为95.98%。LCO|CPE|Li软包装电池在弯曲和剪掉一角后,仍能正常工作,说明具有良好的柔韧性和高安全性。Polyethylene oxide(PEO)polymer-based solid electrolyte(SPE)had good viscoelasticity and film-forming properties,but its application was impeded by low electrochemical window,low ionic conductivity,high thickness,poor strength and lithium anode instability.A PEO/polypropylene carbonate(PPC)-based composite solid electrolyte(CPE)with good interfacial compatibility suitable for high-voltage lithium cobalt oxide(LCO)batteries was prepared by PPC plasticization and using a 5μm base film as a supporting material.The electrolyte showed good electrochemical performance at room temperature,with voltage window up to 0-4.5 V,ionic conductivity up to 4.32×10^(-4) S/cm and Li^(+)migration number up to 0.508.The Li|CPE|Li symmetric cell could be stably cycled for more than 900 h at room temperature and 0.2 mA/cm^(2).The CPE-based batteries had good cycle stability,the capacity retention rate was 95.98%with 60 cycles at 0.1 C in 3.0-4.4 V.The LCO|CPE|Li pouch battery could still work normally after being bended and being cut off a corner,indicating its good flexibility and high safety.

关 键 词：复合固态电解质 聚环氧乙烷(PEO) 聚碳酸丙烯酯(PPC) 高安全性 电化学性能 

分 类 号：TM912.9[电气工程—电力电子与电力传动]