钛酸锂电池胀气成分的气相色谱分析

介绍了使用气相色谱仪(GC)对钛酸锂(Li_4Ti_5O_(12))电池的胀气进行量化分析的方法。电解液成分不同的Li_4Ti_5O_(12)软包电池在55℃循环多次后,产生不同程度的胀气。使用标准气体对气相色谱仪进行标定后,再对电池的胀气成分进行量化分析。发现使用碳酸乙烯酯(EC)作为电解液溶剂的主要成分时,CO_2为生成气体的主要成分,其次是H_2和CO。在EC基的电解液中加入硅烷作为添加剂时,CO_2的含量超过90%,而且产气量也大大增加。当使用碳酸丙烯酯(PC)替换EC,并使用添加剂氟代碳酸乙烯酯(FEC)时,产气量大大减少,生成气体的主要成分是H_2和CO_2。经过数百次循环后,放电态的软包电池放置于55℃烘箱存储两个月,生成气体中H2和CO2的含量减少,CO的含量增多。

Analysis of components of lithium titanate battery by gas chromatography

A method of a quantitative analysis for the gases produced in the lithium titanate (Li4Ti5O12) batteries by gas chromatography (GC) was introduced.The soft-packing lithium titanate batteries produced gases after cycled at 55 ℃.The GC system was calibrated by standard gases.Then the gases produced during cycling were quantitative analyzed.It was found the gases mainly contained CO2,H2 and CO when Ethylene carbonate (EC) was used in the electrolyte.When silanes additive was used in EC-based electrolyte,the battery produced more gases.The volume proportion of CO2 raised to 90％.When Propylene carbonate (PC) was used to replace EC in the electrolyte and using Fluoroethylene Carbonate(FEC) as additive,the battery produced less gases,which contained mainly H2 and CO2.After hundreds cycles,the discharged batteries were stored at 55 ℃ for two months.The volume proportions of H2 and CO2 in the produced gases decreased,and CO increased.