锂离子电池电解液用碳酸酯的电化学行为

锂离子电池的性能与电解液有着密切的关系.介绍了采用线性电位扫描和循环伏安等电化学方法,研究锂离子电池电解液常用的几种碳酸酯在铂电极和碳电极上的电化学行为.研究结果表明,铂电极上线性碳酸酯DEC、DMC和EMC的阴极还原极类似,而环状碳酸酯PC较线性碳酸酯难还原;碳电极上,DEC、DMC和EMC的循环伏安行为相类似,而PC则与锂离子共嵌于碳中,导致锂离子的嵌入量大大增加,而脱嵌锂离子的可逆性却显著降低.

Electrochemical behavior of carbonate solvent used in electrolytes for Li-ion batteries

The performance of lithium - ion battery greatly depends on the nature of electrolytes. Linear sweep, cyclic vohammetry were used to study the electrochemical behavior of carbonate solvents used in Li-ion battery on Pt and carbon electrodes. On platinum electrode, linear carbonate DEC,DMC and EMC have similar cathodic reduction behavior, but ring carbonate PC has lower cathodic currents than linear carbonates. On carbon electrode, DEC, DMC and EMC have similar cyclic vohammetric behavior. However, PC can co-inserte with lithium-ion into carbon, resulting in the increasing of lithium-ion intercalation and the bad reversibility for the intercalation and de-intercalation of lithium-ion.