Method for measuring organic component in lithium ion cell electrolyte

Abstract

This is a test organic component method in lithium ion battery electrolyte. (1) Put DMC,EMC,DEC,EC,PC together into electrolyte and use absolute ethyl as thinner to get standard solution. Carry GC-MS test, get corresponding abundance value and protract standard curve according the content and abundance value of each solvent. (2) Add battery electrolyte into separating funnel and deionwater, surge the admixture for 1-5 minutes, add dichloromethane to surge for 8-12 minutes, eliminate lithium salt; extract the underlayer organic solution to filtrate in terrarium with absolute sodium carbonate. (3) Dilute the liquor got from step (2) into absolute ethyl, and keep its concentration accords with the standard curve range to step (1). (4) Carry GC-MS test in the condition as step (1), account the solvent compose and content of the original battery electrolyte in term of the standard curve to step (1). This method can avoid the cauterization to GC-MS test system by lithium salt component in electrolyte without affecting the fix quantify test to organic component.

Description

Technical field: [0001] The invention relates to a method for determining organic components in battery electrolyte, in particular to a method for determining organic components in lithium-ion battery electrolyte. Background technique: [0002] Lithium-ion battery electrolyte is very sensitive to the energy density, cycle life, safety and other properties of electrodes and batteries. Therefore, choosing a suitable organic electrolyte is one of the key issues to obtain high energy density, long cycle life and battery safety. The initial charge / discharge capacity of the battery varies considerably due to the combination of carbon materials and electrolyte, so special emphasis is placed on the electrolyte being compatible with the carbon anode when designing the battery. In commercial lithium-ion batteries, the lithium salt commonly used in the electrolyte is LiPF 6 , The solvent is a binary, ternary or multi-component system composed of cyclic alkyl carbonates and chain alky...

AI Technical Summary

Problems solved by technology

[0004] However, when GC-MS is used to test the content of organic components in the electrolyte of lithium-ion batteries, the electrolyte lithium salt - lithium hexafluorophosphate will cause corrosion and pollution to the GC system

This is because lithium hexafluorophosphate is easily decomposed to generate LiF and HF. LiF solids are easy to deposit at the liner and column port, and HF will cause irreversible corrosive effects on the column. Therefore, it should be removed before testing with GC-MS system. Removal of lithium salt components, so far, no reports on such methods have been found