Optimization on uniformity of lithium-ion cylindrical battery module by different arrangement strategy

Abstract

Ensuring temperature uniformity of battery module is an important work for the design of battery thermal management system. In this paper, a lithium-ion cylindrical battery module with different cells distribution strategy is designed to improve its uniformity. A three-dimensional heat transfer – one-dimensional electrochemical coupled finite element model is developed to analyze and optimize the arrangement for battery module. The intervals of cells are arranged based on geometric ratio and arithmetic ratio. It is found that the arrangement of varying intervals among cells is an efficient way to improve homogeneity for battery module, especially the arithmetic arrangement. The maximum temperature difference of the battery module decreases with increasing initial spacing. The maximum temperature difference of battery module with arithmetic arrangement could reduce 13%, and maximum final voltage difference could reduce to 2.5 mV when battery initial spacing reaches 5.5 mm. The uniformities of temperature and discharge inside the battery module with arithmetic ratio arrangement are better than geometric ratio arrangement. The position of cells with the maximum temperature in the module varies with discharge time, but always appear at same position regardless of the arrangement and initial spacing. The position changing process is slower in arithmetic arrangement and large initial spacing.