Enhanced optimization algorithm for the structural design of an air-cooled battery pack considering battery lifespan and consistency

Electric scooters are increasingly popular for short-distance commuting. To improve the thermal safety, performance, and lifespan of their batteries, their heat needs to be managed. This study proposes a method for optimizing the air channels in a scooter battery pack. It includes an electro-thermal-degradation model for predicting the battery's electrical and thermal behaviors and capacity loss, a heat transfer model for predicting convective heat exchange between the battery and the air, and a genetic algorithm for structural optimization of an air-cooled battery thermal management system (BTMS). Unlike conventional optimization of a BTMS, the proposed algorithm aims to improve the electrical consistency, lifespan, and thermal safety of the battery via rapid global optimization of its air ducts. The optimization algorithm was tested on a 3P4S air-cooled battery pack from an electric scooter. It improved the pack's consistency of state of charge (SOC) and its lifespan by reducing its heat and temperature gradient. Under on-design conditions, the optimized air ducts reduced the maximum pack temperature by 0.45 degrees C and the difference between the average temperatures of the cells in a branch to 15.9% that of the original pack. Moreover, the optimized air ducts decrease the SOC difference by 81.1% and improved the state of health by 0.03%. Hence, the proposed air duct optimization method can improve the pack's thermal performance, SOC distribution, and lifespan under off-design conditions.

Automated summary

This study proposes a method for optimizing the air channels in a scooter battery pack and demonstrates its ability to improve the thermal performance, SOC distribution, and lifespan of the battery pack through experiments.