Abstract:  In order to meet the requirements of electric vehicle battery thermal management system which is
purposed to reduce the maximum temperature of the battery pack and the temperature difference between single
cells, to overcome the shortcomings of existing air cooling system and series loop water cooling system, to reduce
the maximum temperature and the temperature difference between single cells, a water cooling system with
parallel loop is proposed. Based on the analysis of the heat generation mechanism of lithium ion battery, the
temperature model of the battery was established, and the battery water cooling system with parallel loop was
built in AMESim (Advanced Modeling Environment for Performing Simulation) software. The heat dissipation
performance was compared with the series loop water cooling system via simulation experiments. Good results
have been achieved, the temperature difference is effectively reduced on the basis of maintaining the maximum
temperature of the battery pack, which laid the foundation for the further study of the control algorithm for the
parallel loop water cooling system.

Key words: water cooling system, parallel loop, battery thermal management system, advanced modeling environment for performing simulation(AMESim), battery thermal simulation