物理化学学报2021,Vol.37Issue(12):220-228,9.DOI:10.3866/PKU.WHXB202104003
原位修饰策略实现高倍率室温固态锂电池
In Situ Modification Strategy for Development of Room-Temperature Solid-State Lithium Batteries with High Rate Capability
摘要
Abstract
The increasing development of society has resulted in the ever-growing demand for energy storage devices.To satisfy this demand,both energy density and safety performance of lithium batteries must be improved,which is challenging.Solid-state lithium batteries are promising in this regard because of their safe operation and high electrochemical performance.In recent years,intense effort has been devoted toward the exploration of materials with high ionic conductivity for room-temperature solid-state batteries.Among several types of solid-state electrolytes,Li1.5Al0.5Ge1.5(PO4)3 (LAGP),an inorganic NASICON-type electrolyte,has drawn considerable attention because of its high ionic conductivity,wide electrochemical window,and environmental stability.However,the formation of lithium-ion-conducting networks within the electrode and between the electrode-LAGP interface is limited because of high interfacial resistance caused by the direct contact and volume expansion between the electrode and electrolyte.Thus,the application of LAGP in the fabrication of solid-state batteries is limited.Moreover,the occurrence of the unavoidable side reaction because of the direct contact of LAGP with the lithium metal anode shortens battery life.In addition,the rigid brittle nature of the LAGP electrolyte leads to the limits the facile fabrication of solid-state batteries.To overcome these limitations,herein,a novel strategy based on in situ polymerization of a vinylene carbonate solid polymer electrolyte (PVC-SPE) was proposed.The in situ formed PVC-SPE can effectively construct ion-conducting pathways within the cathode and on the interfaces of the LAGP electrolyte and electrodes.Furthermore,the PVC-SPE can significantly inhibit the side reaction between the lithium anode and LAGP electrolyte.The electrochemical performances of Li | LAGP | Li and Li |LAGP | Li with in situ PVC-SPE modified interface symmetrical solid-state batteries were compared.The in situ modified Li | LAGP | Li symmetrical solid-state battery exhibited stability toward plating and stripping for over 2700 h and a low overpotential (34 mV) at room temperature.Moreover,a Li | LAGP | LiFePO4 solid-state battery exhibited a capacity retention of 94% at 0.2 C after 200 cycles with a capacity of 158 mAh·g-1.In addition,high rate capability (72.4% capacity retention at 3 C) was achieved at room temperature.Therefore,the proposed in situ modification strategy was found to resolve the interface-related problem and facilitated the construction of the ion-conducting network within the electrode;thus,it can be a promising approach for the fabrication of high-performance solid batteries.关键词
离子网络/界面/原位聚合/固态电池Key words
Ion network/Interface/In situ polymerization/Solid-state battery分类
化学化工引用本文复制引用
赵江辉,沈炎宾,陈立桅,谢茂玲,张海洋,易若玮,胡晨吉,康拓,郑磊,崔瑞广,陈宏伟..原位修饰策略实现高倍率室温固态锂电池[J].物理化学学报,2021,37(12):220-228,9.基金项目
The project was supported by the National Natural Science Foundation of China (21625304,21733012,and 21772190) and the Ministry of Science and Technology of China (2016YFB0100102).国家自然科学基金(21625304,21733012,21772190)和中国科学技术部国家重点研发计划(2016YFB0100102)资助项目 (21625304,21733012,and 21772190)