Experimental investigation on reciprocating air-cooling strategy of battery thermal management system

With the increasing demands on the battery packs equipped on the electric vehicles, the temperature non-uniformity issue needs impactful solutions, like reciprocating air-cooling. Despite thorough investigations on this technique, most of them were carried out using simulation method, which incurred the gap between the calculation results and the engineering practice. This paper investigated the reciprocating airflow in Z-type Battery Thermal Management System (BTMS) experimentally, including the key parameters and the novel control scheme. Firstly, five control parameters of reciprocating air-cooling were discussed, and the optimal reciprocating airflow decreased 65.5 % of maximum temperature difference compared to the original model. Then, empirical formulas were proposed to illustrate the relationship of these parameters, and the average relative error of the calculation result were 0.07 % and 6.6 % for T_max and T_diff respectively compared with the experimental validation. Ultimately, a novel intermittent cooling scheme, which was able to save up 10.1 % energy in comparison with the continuous cooling, was designed to cater for the practical applications. Results of this study validated that optimal reciprocating airflow can overtly improve the temperature uniformity within the battery pack, facilitated the practical engineering application, and provided a novel route for the cooling scenario for the air-based BTMS.