作　　者： ; ; ; ; ; (刘建生）;

机构地区： 华南师范大学化学与环境学院化学系

出　　处： 《电池工业》 2006年第3期185-189,共5页

摘　　要： 介绍了用循环伏安法研究石墨在D EC、D M C、EM C和PC单组分电解液以及以PC、E C为基础的电解液中的电化学行为。研究结果表明:D EC、D M C和EM C 3种线型碳酸酯溶剂表现出相似的伏安行为,而环状碳酸酯溶剂PC则表现出不同的伏安行为,单纯用PC作锂离子电池电解液的溶剂,PC极易嵌入石墨中,并使锂离子在石墨中的脱出峰电位变正;线型碳酸酯溶剂DM C与PC的混合可以降低锂离子在石墨中的脱出峰电位,但不能抑制PC嵌入石墨电极;EC能对PC嵌入石墨电极起抑制作用,通过调整溶剂的配比可以完全抑制PC嵌入石墨。研究了PC,EC及DM C混合溶剂电解液的053048型锂离子电池的循环性能。结果表明,电池的初始容量和循环稳定性随着电解液中D M C含量的增加而增加。电解液组成为1m olL/LiPF6/EC∶PC∶DM C=1∶1∶4的电池初始容量接近理论容量,经50次循环后容量衰减很少,容量保持率高达97%。 The electrochemical behavior of graphite by cyclic voltammetry, The voltammetric behavior in solutions with different compositions of solvents was studied of DEC, DMC and EMC is very similar, while that of PC is different. PC can easily insert into graphite when it is solely used as solvent and improve the de-intercalation peak potential value of lithium ion in graphite. The de-intercalation peak potential of lithium ion in graphite decreases when PC is mixed with DMC, but the co-intercalation behavior of PC solvent cannot be eliminated. EC can inhibit the co-intercalation of PC with Li ion in graphite. The cyclic performance of 053048 Li-ion batteries using electrolyte with PC, EC and DMC as solvents were studied. It was found that the initial capacities and the cyclic stability of the cells were improved with the percent of DMC increasing in the electrolytes. The Li-ion battery with lmol LiPF6/EC： PC： DMC = 1： 1：4 showed good cyclic life, the capacity decreased little and remained 97% after 50 cycles.

关 键 词： 锂离子电池 电解液 溶剂 共嵌

领　　域： [电气工程]