Li_(2)CO_(3)材料在锂离子电池中过充产气的作用机理

Overcharge Gas Generation Mechanism of Li_(2)CO_(3) in Lithium Batteries

Li_(2)CO_(3)材料作为三元电池重要的过充产气添加剂,但其产气机理尚未得到深入的研究。通过在电解液中加入Li_(2)CO_(3)或微量水分,并封装于铝塑膜中,通过模拟电池过充温升对铝塑膜进行加热处理。通过铝塑膜外貌观察及排水法对其加热后的产气量进行定性测量,采用酸碱滴定法检测电解液中HF酸含量以及气相色谱(GC)检测产气成分等。结果显示,Li_(2)CO_(3)过充产生的气体主要是CO_(2)气体,且必须在一定的酸性环境下才能有效地被诱导产气。

Li_(2)CO_(3)is an important overcharge additive for ternary batteries,but its gas production mechanism has not been studied in depth.In this paper,by adding Li_(2)CO_(3)or trace water into the electrolyte and encapsulating it in the aluminum-plastic film,the aluminum-plastic film is heated by simulating the overcharge heating temperature rise.By means of appearance observation and drainage method,gas production was quantitatively characterized.HF acid content in electrolyte was detected by acid-base titration,and gas production components were detected by GC.The results show that the gas produced by Li_(2)CO_(3)overcharge is mainly CO_(2),and it must be under certain acid environment to be effectively induced to produce gas.