Air-Outlet and Step-Number Effects on a Step-like Plenum Battery’s Thermal Management System

Optimizing the control of the battery temperature (Tb), while minimizing the pressure drop (∆P) in air-cooled thermal management systems (TMSs), is an indispensable target for researchers. The Z-type battery thermal management system’s (BTMS’s) structure is one of the widely investigated air-cooled TMSs. Several designs of air-cooled BTMSs are often associated with the drawback of a rise in ∆P, consequently resulting in an increase in pumping costs. In this study, the investigation of a Step-like plenum design was extended by exploring one and two outlets to determine possible decreases in the maximum battery temperature (Tmax), maximum battery temperature difference (∆Tmax), and pressure drop (∆P). The computational fluid dynamics (CFD) method was employed to predict the performances of different designs. The designs combine Step-like plenum and two outlets, with the outlets located at different points on the BTMS. The results from the study revealed that using a one-outlet design, combined with a Step-like plenum design, reduced Tmax by 3.52 K when compared with that of the original Z-type system. For another design with two outlets and the same Step-like plenum design, a reduction in Tmax by 3.45 K was achieved. For ∆Tmax, the use of a two-outlet design and a Step-like plenum design achieved a reduction of 6.34 K. Considering the ∆P performance, the best- and poorest-performing designs with two outlets reduced ∆P by 5.91 Pa and 3.66 Pa, respectively, when compared with that of the original Z-type design. The performances of the designs in this study clearly show the potential of two-outlet designs in reducing ∆P in systems. This study, therefore, concludes that the operational cost of the Step-like plenum Z-type BTMS can be reduced through the careful positioning of the two-outlet section, which will promote the design and development of current and future electric vehicle (EV) technologies.