Uniforming thermal distribution by air-convection aspirated in partially hollowed tetrahedral lattice porous cold plates for the drone battery

• There exist temperature variation in pouch-type lithium-ion batteries. • The purpose of a lattice porous medium cold plate is to improve the temperature uniformity • The experimental and numerical analysis of aspirated flow conditions were investigated. • The separation flow is observed in the inlet region of internal cold plate channel • The developed flow along the internal channels was fully mixed. A pouch-type lithium-ion battery requires effective thermal management and a solution for temperature imbalances depending on its morphological characteristics. In this study, we present such a solution for rows of pouch-type lithium-ion battery cells controlled by aspirated air convection in a tetrahedral lattice porous cold plate, as well as by reducing the temperature imbalance in the lattice porous medium (LPM). The hollowness ratio (HR) was applied to the ligament, and its effect was investigated in the entrance region of the cold plate channel. A series of steady-state numerical simulations and experiments were conducted to demonstrate the effectiveness of the solution. As a result, the temperature deviation in the longitudinal direction of the LPM cold plate's lower substrate was 6.4°C under the 7 C-rate heat source condition. Owing to the inlet effect of forced convection due to the aspirated airflow, the lowest temperature was observed on the inlet side, and a higher temperature was observed on the outlet side. By applying the HR to the ligament of the LPM cold plate, it was confirmed that the temperature deviation decreased to 4.4°C, which was 2°C lower than that applied to the simple solid ligament. In addition, the temperature uniformity index (TUI) was 0.96, when the hollowness ratio was 0.64.