Study on the cooling performance of a new secondary flow serpentine liquid cooling plate used for lithium battery thermal management.

• Secondary flow was introduced to improve the performance of serpentine channel BTMS. • A grid + elliptical groove serpentine channel plate is proposed in this paper. • Pump power is reduced by 92.6 % and cooling efficiency coefficient is increased by 11.097 times. • Clear the coolant flow trajectory and eddies distribution. • Sensitivity analysis to further clarify the mechanism of cooling. To improve the thermal and economic performance of liquid cooling plate for lithium battery module in the distributed energy storage systems, on the basis of the traditional serpentine liquid cooling plate, the unidirectional secondary channels and grooves are added, combined to three kinds of serpentine cold plates for the battery module. By contrast, the cold plate with both elliptical groove and secondary channel has the best comprehensive performance. Though the thermal performance is slightly reduced, the consumption of pump power is reduced by 92.6 % and the cooling efficiency coefficient is improved by 12.32 times compared to the original cold plate. The cooling temperature targets of the battery pack are that T max less than 40℃ and Δ T avg less than 3 K. In order to achieving the best performance of the cold plate, the influence of the structural parameters and hydrodynamic parameters on the performance index is analyzed, and the sensitivity analysis is carried out which clear the operational mechanism and key design parameters of the cold plate. The results show that different design parameters would generate the change of eddy current which is influential to the cooling performance. Besides, v and D have a significant effect on the performance of the cold plate, followed by d and n, and a has almost no effect on the cooling performance. [ABSTRACT FROM AUTHOR]