1. Tianjin Institute of Power Sources, Tianjin, China Dr. Songrui Wang
Multiphysics Simulation Story: Battery Simulation Propels Electric Cars in China
Tianjin Institute of Power Sources, Tianjin, China
Dr. Songrui Wang

2. The Challenge
Lithium ion batteries are becoming increasingly more popular for use in cars
Lithium-ion cells currently power most laptops and cell phones because they are smaller and lighter than alternatives
Thermal behavior of these batteries must be understood so that they may be better adapted for safe use in new applications
Plot of temperature and temperature rates over time in a Li-ion cell; the region and extent of thermal runaway is pretty evident from the sudden increase in temperature and temperature rate.

3. The Solution
By finding which factors impact cell safety significantly, design recommendations can be made to prevent injury
Thermal behavior of the cells can be tested at adiabatic conditions using the models, eliminating those factors that do not alter results
Risk of potential fire hazards can then be detected and evaluated against other design variations
Calculating exothermal peaks allows for the detection of appropriate boundaries for battery design and use in vehicles
The use of COMSOL cut number of experiments ($300 per experiment) from hundreds to around ten

4. The Simulation
Create a 3D model with 12 positive electrodes, coupled with heat transfer and electrochemical reactions
Optimize cell geometry and study thermal behavior of materials
The cell’s temperature distribution when thermal runaway occurs.