Clarification of the dispersion mechanism of three typical chemical dispersants in lithium-ion battery (LIB) slurry

Abstract

This paper mainly clarified the dispersion mechanism of three typical chemical dispersants which are polyethylene glycol octylphenyl ether (Triton X-100, T-100), polyethylene pyrrolidone (PVP) and carboxymethyl cellulose (CMC) within lithium-ion battery (LIB) slurry. Initially, the optimum amounts of T-100, PVP and CMC are selected from 0%, 0.5%, 1.5% and 2.5% by evaluating the impedance of LIB slurry in the case of adding each typical chemical dispersant with EIS method. Moreover, the impedance spectrum of three different slurry samples which are PVDF-NMP solution, LiCoO2 slurry and Carbon Black (CB) slurry with the optimum amount of each dispersant are also investigated. After using SEM and C element distribution images of LIB slurry to verify the correctness of the dispersion mechanism of each dispersant, it is concluded that the dispersion CMC with its optimum amount 1.5% is the best one to promote the formation of conductive paths and CB-coated LiCoO2 network structure within LIB slurry, which has the considerably potential to improve the performance of LIB.