2023.7Vol.47No.7研究与设计收稿日期:2023-01-18基金项目:天津市自然科学基金项目(20JCYBJC00690)作者简介:于利伟(1982—),男,山东省人,硕士,主要研究方向为新能源领域。通信作者:孟繁慧,E-mail:123mfh@163.comNCM811-SiO/石墨锂离子电池电解液研究于利伟,岳仍利,张方忠,朱莎,孟繁慧(天津力神电池股份有限公司,天津300384)摘要:研究了电解液配方对NCM811-SiO/石墨锂离子电池性能的影响。本研究的电解液配方中,FEC、LiPO2F2、VC和PS等添加剂的选择及配比影响电池的容量、首效、电压平台和内阻。FEC和VC不利于倍率性能及电池高温性能,但有助于电池的循环性能。LiPO2F2和PS有利于高温存储性能,但是不利于电池循环性能,PS可提升电池倍率性能。LiFSI作为LiPF6的辅助锂盐,有利于电池的容量、首效、电压平台提升和电池内阻降低;同时,LiFSI的添加有助于改善电池的倍率性能、低温性能和循环性能。电池设计开发时,需要结合电池性能要求,对电解液添加剂和锂盐进行综合考虑。关键词:高比能;锂离子电池;电解液;添加剂;锂盐中图分类号:TM912文献标识码:A文章编号:1002-087X(2023)07-0873-05DOI:10.3969/j.issn.1002-087X.2023.07.011StudyofelectrolyteforlithiumionbatterieswithNCM811cathodeandSiO/graphiteanodeYULiwei,YUERengli,ZHANGFangzhong,ZHUSha,MENGFanhui(TianjinLishenBatteryJoint-stockCo.,Ltd.,Tianjin300384,China)Abstract:TheeffectofdifferentadditivesandlithiumsaltsontheperformanceoftheNCM811-SiO/graphitelithiumionbatterywasdiscussed.Fortheelectrolytes,thecombinationofFEC,LiPO2F2,VCandPSaffectedthebattery'sbasicelectricperformancecontainingcapacity,initialefficiency,voltageplatformandinnerresistance.FECandVCwereharmfultobattery'srateperformance,madehightemperatureperformanceworse,butbenefitedthecycleperformanceofbattery.PShadapositiveeffectontherateperformance.LiPO2F2andPShelpedimprovethestorageperformanceatahightemperature.However,theintroductionofLiPO2F2andPSledtoworsecyclingperformance.Whenusedasanauxiliarylithiumsalt,LiFSIhadapositiveeffectonbattery'sfundamentalperformance,rate,lowtemperature,andcyclingperformance.Toachievebettercomprehensiveperformanceofthebatteries,theadditivesandlithiumsaltsshouldbetakenintoaccountcompreh...