用指示剂法和电位滴定法,分别以氢氧化四丁基铵、氢氧化钠、氢氧化钾和甲醇钠为滴定剂。以甲醇或乙醇作为溶剂对锂离子蓄电池用电解液中游离酸度的测定进行了研究。考察了电解液中稳定剂和溶剂中微量水分的存在对分析结果的影响。结果表明,电解液中氧氟酸测定的最佳条件为:乙醇作溶剂,滴定剂为氢氧化钾,测试方法为电位滴定法。乙醇中微量水分的存在不影响测试结果,稳定剂的加入会提高电解液的碱性,会给指示剂法的测定带来较大的误差。
The HF content in electrolyte for lithium ion battery was determined by indicator method and potentiometric titrimetry, using BTB ,NaOH ,KOH and CH3ONa as titrant, CH3OH or C2H5OH as solvent, respectively. The influence of stabilizer in electrolyte and micro-water in solvent on quantitative analysis were also investigated. Then the optimal HF content analysis system was developed based on the test results, The results show that a sufficiently sharp change will occur when using C2H5OH as solvent, KOH as titrant, and a more exact result can be obtained by means of potentiometric titrimetry than by an indicator method, the exist of micro-water in solvent does not influence the titration result.