摘要
在锂离子电池电解液1 mol/L六氟磷酸锂/碳酸乙烯酯+碳酸二甲酯+碳酸甲乙酯(体积比为1∶1∶1)溶液中添加丁二酸酐作为提高电池充放电效率的添加剂。采用恒流充放电测试、循环伏安曲线、线性伏安曲线和电化学阻抗谱等手段,研究了添加剂丁二酸酐对电解液电化学稳定窗口的影响,以及丁二酸酐与锰酸锂材料的相容性。结果表明:在电解液中添加2%(质量分数)的丁二酸酐,提高了LiMn_2O_4/Li电池常温和高温容量保持率。丁二酸酐可以优先于基础电解液发生少量氧化分解,从而降低了LiMn_2O_4/Li电池的极化。同时,丁二酸酐也可降低电池循环过程的阻抗。
Succinic anhydride （SA） was selected as an additive to improve the charge-discharge efficiency in lithium-ion bat- teries.The base electrolyte is 1 mol/L LiPF6/[ethylene carbonate （EC） ＋diethyl carbonate （DMC） ＋ethyl-methyl carbonate （EMC） ] （volume ratio of 1：1：1 ）.Constant current charge-discharge test, cyclic voltammeter curves, linear sweep vohammetry （LSV）, and electrochemical impedance spectra （EIS） were used to investigate the influence of SA on electrochemical stabi- lity window of electrolytes as well as the compatibility of SA with LiMn2O4 electrode.Results showed the capacity of LiMn2O4/ Li cell using electrolyte with 2% （mass fraction） SA was increased,whether it was at room temperature or high temperature. The electrolyte with SA had a lower oxidative stability than base electrolyte and thus decomposed first and reduced the pola- rization of LiMn2O4/Li cell.Meanwhile, SA could also reduce the impedance of the cells in the cycles.
出处
《无机盐工业》
CAS
北大核心
2016年第12期82-85,共4页
Inorganic Chemicals Industry
基金
国家高技术研究发展计划(863)新材料领域(批准号:2013AA050901)
关键词
丁二酸酐
充放电效率
电解液
电化学阻抗
succinic anhydride
charge-discharge efficiency
electrolyte
impedance
