Investigation on the thermal management performance of a non-contact flow boiling cooling system for prismatic batteries

Abstract

It is a great challenge to control the temperature of high energy-density lithium-ion batteries within an appropriate working range during rapid charging and discharging with a battery thermal management system (BTMS). As a hot topic in current BTMS research, boiling cooling technology with high heat transfer efficiency is a reliable way to solve these thermal management problems. In this study, a novel thermal management system for prismatic batteries based on cooling by non-contact flow boiling is proposed, and various cold-plate structures are considered with different numbers and locations of coolant inlets and outlets inside the cold plate cavity, and with different numbers and arrangements of ribs and fins. A three-dimensional transient model was conducted to investigate the effect on the cooling performance of the boiling BTMS of several variables — notably inner-channel design schemes, the number of ribs or fins in the cold plate, coolant inlet temperatures, and inlet Reynolds numbers. The results indicate that among the six design schemes that were considered, the best comprehensive heat transfer performance is achieved with two pairs of inlets and outlets, a vertical fin arrangement, and fin height equal to 3/4 of the inner channel dimension. With an increase in the number of fins, the maximum temperature and maximum temperature difference of the structures that were considered decrease by no <0.8 °C and 0.2 °C, respectively. Also, the temperature uniformity of the battery pack can be improved by appropriately increasing the coolant inlet temperatures and reducing the inlet coolant flow rate. When the number of fins is 19, the inlet temperature is 29 °C, and the inlet Reynolds number is 893, the preferred BTMS is always able to maintain its maximum temperature below 35.67 °Cand the maximum temperature difference to below 4.47 °C, at 3C high discharge rate.