Structure optimization of air cooling battery thermal management system based on lithium-ion battery

Air cooling is a common and valid method to improve the heat distribution of battery thermal management system (BTMS). To further improve the heat distribution in BTMS, the spoiler is applied to the air cooling BTMS. To investigate the applicability of this strategy, two common BTMSs, the Z-type BTMS (the BTMS I) and the U-type BTMS (the BTMS II), are selected as the study objects, then, two novel structures (i.e., the BTMS III and the BTMS IV) are proposed, where the spoiler is installed at the air inlet manifold of the two initial BTMSs, respectively. By studying three structural parameters (i.e., the spoiler length L, the spoiler height H and the offset distance of spoiler S) of two novel structures, two optimal BTMSs corresponding to them (the BTMS III-opt and the BTMS IV-opt) are obtained respectively. At the inlet velocity of 3.5 m/s, calculations have been conducted. The results demonstrate that after optimization, the maximum temperature (T_max) and the maximum temperature difference (∆T_max) of the BTMS III-opt are 327.43 K and 3.64 K respectively, decreased by 2.56 K and 3.44 K (48.61%), compared with the BTMS I. Meanwhile, in comparison with the BTMS II, T_max and ∆T_max of the BTMS IV-opt are 326.29 K and 1.19 K respectively, decreased by 2.79 K and 4.98 K (80.68%). The results illustrate that installing spoiler at the air inlet manifold is a valid way to improve the heat distribution of BTMS.