AUTHOR=Chang Long , Ma Chen , Luan Chunxiao , Sun Zhezhe , Wang Cunyu , Li Hongyu , Zhang Yulong , Liu Xiangqi 

TITLE=Influence of the Assembly Method on the Cell Current Distribution of Series–Parallel Battery Packs Based on Connector Resistance

JOURNAL=Frontiers in Energy Research

VOLUME=Volume 10 - 2022

YEAR=2022

URL=https://www.frontiersin.org/journals/energy-research/articles/10.3389/fenrg.2022.804303

DOI=10.3389/fenrg.2022.804303

ISSN=2296-598X

ABSTRACT=In order to meet the energy and power requirements of large-scale battery applications, lithium-ion batteries have to be connected in series and parallel to form various battery packs. However, unavoidable connector resistances cause the inconsistency of the cell current. Meanwhile, different assembly methods and module collector position (MCP) may result in different connector resistance arrangements, thereby leading to different cell current distributions. Therefore, the correlation of connector resistance on battery pack performance is worth investigating. Based on the simplified equivalent circuit model (ECM), the mathematical models of cell current distribution under different assembly methods are obtained in this paper. The series-parallel battery pack is constructed through the assembly method with better cell current consistency. Then, we use COMSOL Multiphysics simulation to analyze the guideline of series assembly for parallel modules and study the influences of connector resistance and MCP on series-parallel battery packs. The results show that the assembly method with equal distance between each cell and assembly contact surface is more suitable for series assembly for parallel modules. The effect of series-parallel battery pack under Z configuration and ladder configuration is the same. In addition, the non-edge parallel module part of series-parallel battery pack can be replaced by series cell module (SCM) structure.