Research on precise temperature control performance of battery thermal management system integrating piezoelectric pump and thermoelectric cooler

In this paper, a battery thermal management system (BTMS) integrating piezoelectric pump (PP) and thermoelectric coolers (TEC) was designed. In addition, phase change materials (PCM) were also added to the system. When the battery pack was discharged uniformly, the driving frequency of PP was adjusted to ensure that the battery temperature does not exceed the limit value (318.15K) during discharge. A control strategy was designed to adjust the driving frequency of the PP according to the temperature of the outlet coolant and discharge rate of battery when the battery discharge was not uniform, which can ensure that the temperature difference between battery packs does not exceed the limit value (5K). In addition, the suppression effect of thermal management system on thermal runaway under different TEC current was also studied. The experimental and simulation results showed that when the battery pack was discharged uniformly at 2C or 3C, and the driving frequency of the PP was 40HZ and 60HZ respectively, the battery temperature does not exceed the limit and the PCM can be completely transformed to be fully utilized. According to the control strategy, the battery temperature uniformity can be ensured. In addition, the thermal runaway propagation can be effectively inhibited when the TEC current is 4A.