High-temperature cooling via metal 3D-printed cold plates for battery thermal management

This study proposed an original design of a cold plate for battery thermal management systems (BTMS) using selective laser melting (SLM) as one of the established metal additive manufacturing techniques. The cold plate had the dimensions of 50 mm×50 mm×6 mm with a cavity, where the coolant circulated, with a height of 4 mm. To increase the heat transfer performance, body-centered cubic (BCC) elements with the unit cell length and the strut radius of 4.0 mm and 0.5 mm, respectively, were placed into the cavity. The applied heat flux rate was 1049±44.9 W/m2 which was in the class of high heat flux application in BTMS. The coolant (water) temperature was selected at 26.3 °C as it was the tap water temperature in Singapore whilst it was able to project the cooling performance of the cold plate with a relatively high temperature compared to traditional cooling applications via cold plates in BTMS. Two different water flow rates of 5.5 L/h and 11.2 L/h were performed for cooling the cold plate when its surface temperature reached the values of 40.0 °C and 42.5 °C, respectively. Results showed that the cold plate temperature was cooled down below 35.0 °C, which was the main goal of the study, in less than 15.5 minutes and 19.5 minutes when the initial surface temperatures were 40.0 °C and 42.5 °C. The corresponding coefficient of performance (COP) was found in the range of 24.5-42.6 and 6.2-10.1 for the water flow rates of 5.5 L/h and 11.2 L/h, respectively, during the experimental period. It was inferred that cooling down the surface temperature below 35.0 °C by supplying the coolant temperature of 26.3 °C was practically possible even if the coolant time was relatively high and the ambient conditions were high-temperature and high-humid. Thus, further improvements including material-based and parametric solutions were also discussed in the study.