Analysis of Heat Generation from a Pouch-Type Lithium-Ion Battery Cell Considering Its Electrochemical Characteristics

摘要

The energy density of a battery cell, which is a key component of an electric vehicle, is expected to increase gradually to reach 400Wh/kg in 2020. The increase in the energy density of the battery cell to improve the mileage leads to an increase in the heating value, and the internal temperature management becomes a very important technical issue. Battery thermal management of electric vehicles is an important factor associated with battery performance, efficiency, lifetime, and safety. In order to ensure the performance and stability of the battery cell, it is necessary to understand the characteristic of heat generation of the battery cell according to the electrochemical behavior under various working conditions and to perform the thermal management using the proper cooling method. In this study, we investigate the heat generation characteristic of battery cell according to electrochemical behavior by numerical simulation of pouch type lithium ion battery which reflects electrochemical characteristics three dimensionally. The computational simulation model of the lithium ion battery developed in this study is for a lithium ferrophosphate (LFP) battery cell. Three dimensional multiphysics battery cell modeling combines physical phenomena for charge transfer, mass transfer, and heat transfer. Through the results obtained from this study, we will understand the thermal behavior of lithium ion battery and obtain effective cooling method to secure the performance and safety of lithium ion battery.