Design optimization of water cooling system for vehicle lithium battery pack based on thermodynamic exergy theory

Tian Hao, Pan Chuiyu and Zhang Qun

2021.05.20

Based on the thermodynamic exergy theory, optimizes the water cooling system of vehicle lithium battery pack and establishes an exergy loss model. For the lithium battery of an electric SUV car, compares the temperature control effects of four typical water-cooled layouts by means of theoretical analysis and practical test. Under different discharge conditions, tests the maximum temperature difference and location of single cell in four kinds of water-cooled layout. The test results show that the exergy loss of heat transfer network for the lithium battery pack is the smallest when the cooling water first flows through the central area of the battery pack. The measured maximum temperature difference of the battery pack is 3.1 K, which is lower than the other three water-cooled layouts, and the maximum temperature of each single cell is 1.1 to 5.9 K lower than the other three water-cooled layouts. The theoretical analysis is in good agreement with the experimental results, which proves that the exergy theory can be used in the optimization design and improvement of the heat dissipation of the vehicle lithium battery.