A reliability-based design concept for lithium-ion battery pack in electric vehicles

Battery technology is an enabling technology for electric vehicles (EVs), and improving its safety and reliability while reducing its cost will benefit its application to EVs. In this paper, a method on the design and analysis of lithium-ion (Li-ion) battery pack from the reliability perspective is presented. The analysis is based on the degradation of the battery pack, which is related to the cells configuration in the battery pack and the state of health (SoH) of all the Li-ion cells in the pack. Universal Generating Function (UGF) technique is used for reliability analysis. As adding new battery cells to the battery pack in the production process can improve its reliability but it also increases cost, tradeoff between the number of the redundant battery cells, the configuration of the redundant cells and their reliability is investigated in this work.