Thermal performance of Lithium-Ion battery pack with optimised bionic channel using Multi-Objective genetic Algorithm: A numerical Investigation

Lithium-ion (Li-ion) cells play a pivotal role in electric vehicles (EVs) and their effective thermal management is crucial for enhanced safety and longevity. Three dimensional mathematical model of the battery containing cylindrical cells with bionic structured cooling channel was developed and simulated with different coolants at different C-rates and inlet velocities in the present study. The novelty lies in the themo-hydraulic performance comparison of bionic channels such as fishbone and spiderweb. The best coolant-channel combination undergoes optimisation study using multi-objective genetic algorithm for better thermal performance. Temperature difference (Delta T) is in the desired limits and lower than its counterpart, and Pressure drop (Delta P) is lower than its counterpart at all discharge conditions in fishbone design. Rate of increase in Delta P and decrease in Delta T with velocity are higher and lower, respectively in spiderweb channel. 63.38 % and 43.45 % lower Delta T and Delta P, respectively are existing in the fishbone channel than spiderweb at a 5C discharge and 0.07 m/s inlet velocity, which demonstrate its superiority. 2.96 K and 3.58 K difference in Tmaxand Delta T are observed between water and glycol-water mixture coolants, respectively with fishbone at 5C. The fishbone channel with water coolant demonstrates best desired characteristics and this combination was considered for channel optimisation studies. Optimizing the channel angle, significantly impacts Delta P and statistical analysis indicates that reducing the angle from 90 degrees to 85 degrees decreases the Delta P from 15.15 Pa to 9.44 Pa. Lower angled channels are recommended for improved overall performance.