Performance analysis and optimization of a hybrid battery thermal management system integrating PCM with Chinese knot-shaped liquid cooling plate

The battery thermal management system (BTMS) with phase change material (PCM) faces high risk of battery temperature runaway once the PCM is completely melted. To ameliorate this dilemma, a hybrid BTMS integrating PCM with the innovative Chinese knot-shaped liquid cooling plate is introduced in this paper, the performance of which is explored and compared to that of a hybrid BTMS with the traditional liquid cooling plate. Firstly, two parameters of cooling channel in novel liquid cooling plate are investigated. Then, the liquid cooling plate arrangement and coolant operating parameters are optimized by the respond surface method. Ultimately, the thermal control capacity of hybrid BTMS are evaluated under harsh conditions. The results illustrate that compared to the traditional liquid cooling plate, the Chinese knot-shaped liquid cooling plate reduces the maximum temperature (Tmax) and maximum temperature difference (Delta Tmax) of batteries by 7.04 K and 0.51 K respectively and increases the coefficient of performance by 10 %. Enlarging the channel radius and channel-tochannel distance enhances the heat transfer performance of the novel liquid cooling plate, thereby decreasing the Tmax and Delta Tmax of batteries. At 6C discharge rate, the Tmax and Delta Tmax of the optimal design are maintained at 313.15 K and 3.61 K respectively, and they are 3.33 K and 0.82 K lower separately than those of the original design. The proposed hybrid BTMS can control the Tmax within the suitable operational temperature scope under the rapid discharge rate of 8C or the high ambient temperature of 318.15 K.