Development and performance analysis of a multifunctional composite phase change cooling plate for improving battery thermal management

This study offers a novel multifunctional composite phase change cooling plate (MCPCP) to meet the multifarious management requirements of lithium batteries. The constituents of the MCPCP comprise nanostructured silicon dioxide, ammonium polyphosphate, glycerin, expanded graphite, and eutectic phase change material (EPCM). First, the impacts of nanostructured silicon dioxide, ammonium polyphosphate, and glycerin on the mechanical properties and flame retardancy of PDMS were assessed. Following the addition of expanded graphite and EPCM, the cooling performance of the composite PDMS was next investigated. Furthermore, the integration performance of the MCPCP with a film heater and photovoltaic conversion device was investigated and evaluated. Finally, the efficacy of the MCPCP for monitoring battery expansion was evaluated. The findings indicated that the integration of nanostructured silicon dioxide significantly improved the tensile strength of PDMS by 31.6 % and its toughness by 375.3 %, while expanded graphite substantially increased thermal conductivity by 366.7 %. The maximum temperature of the battery can be decreased by 8.5 ℃ at a working current of 102 A after incorporation of EPCM. The film heater, powered by a 21,700 battery, was capable of preheating a prismatic battery from −10 ℃ to 14.6 ℃, with an average preheating rate of 0.38 ℃·min⁻¹ and a temperature difference of 2.6 ℃. The properly designed MCPCP demonstrated an effective means to monitor the aging and thermal runaway expansion of the battery. This study serves as a significant reference for the development of a multifunctional battery thermal management system and advancing its level of integration.