摘要
液态电解液存在泄漏爆燃隐患,在锂金属电池中的实际应用受限。基于离子液体制备的聚合物固态电解质(SPE)具有阻燃性好、热稳定性好、化学与电化学稳定性高等优点,在锂金属电池上的应用前景很好。设计合成一种离子液体单体(IL),并与碳酸乙烯亚乙酯(VEC)通过自由基聚合反应共聚,制备基于P(IL-VEC)的SPE。该SPE具有良好的热稳定性和阻燃特性,室温下离子电导率较高,可抑制锂枝晶的生长,达到稳定电解质与电极界面。以该SPE匹配磷酸铁锂正极组装的全固态锂电池,循环稳定性和倍率性能较好。以0.2 C倍率在2.8~3.8 V循环,初始放电比容量达154 mAh/g,并可稳定循环超过200次,在第230次循环时的剩余容量为118 mAh/g。
Liquid electrolyte had the hidden danger of leakage and deflagration,its practical application in lithium metal battery was limited.Solid polymer electrolyte(SPE)prepared using ionic liquids had several advantages,including good flame-retardant property,good thermal stability and high chemical and electrochemical stability,thus had good potential for use in lithium metal battery.A novel ion-liquid monomer(IL)was designed and synthesized,which was copolymerized with vinyl ethylene carbonate(VEC)using a free radical polymerization reaction to prepare P(IL-VEC)-based SPE.The SPE exhibited good thermal stability and flame-retardant property and demonstrated high ionic conductivity at room temperature,which could inhibit the growth of lithium dendrite and achieve stable electrolyte-electrode interface.The all solid-state lithium battery using a lithium iron phosphate cathode and the SPE exhibited good cycling stability and rate capability.It could deliver an initial specific discharge capacity of 154 mAh/g at a rate of 0.2 C cycled in 2.8-3.8 V,with stable cycling for more than 200 times and a remaining capacity of 118 mAh/g at the 230th cycle.
作者
谢思思
王海燕
XIE Si-si;WANG Hai-yan(Basic Teaching Department,Huanghe Jiaotong University,Jiaozuo,Henan 454950,China;School of Materials Science and Engineering,Henan Polytechnic University,Jiaozuo,Henan 454000,China)
出处
《电池》
CAS
北大核心
2023年第6期652-656,共5页
Battery Bimonthly
基金
国家自然科学基金(11404099)。
