Performance enhancement of a battery thermal management system using novel liquid cold plates with micro-channel featuring pin fins

The battery thermal management system (BTMS) with liquid cold plates has been proven to be effective in temperature control and heat transfer. In this work, a novel liquid cold plate featuring pin fins for the cooling of prismatic lithium-ion batteries is proposed. The performances of BTMS with liquid cold plates are numerically investigated by using a three-dimensional CFD model and compared under different coolant inlet velocities, pin fins' heights, and arrangements. The efficiency index (EI) is employed to evaluate the comprehensive performances of cold plates by considering heat transfer and liquid flow. The results indicate that the introduction of pin fins contributes to improving the heat transfer performance and thus reducing the maximum battery temperature rise (ΔTrise) and temperature difference (ΔTdiff). Besides, both the ΔTrise and ΔTdiff increase as the pin fins' height (PFH) decreases. However, the cooling micro-channel with pin fins featuring a dimensionless height (Hd) of 1/4 provides the best thermo-hydraulic performance and the lowest power consumption under the same battery thermal performance. In addition, the cooling micro-channel with pin fins placed on two opposite heat transfer walls exhibits better heat transfer performance and thus better battery thermal performance, compared with the cooling micro-channel with pin fins placed on the single heat transfer wall. When the coolant inlet velocity of 0.4m/s at a 3C discharge rate the ΔTrise and ΔTdiff of the cold plates with pin fins staggered arrangement in stream-wise direction for the opposite walls on both top and bottom walls are reduced by 4.045K and 3.122K, respectively, compared with the cold plates without pin fins.