Facile preparation method of phase change microcapsule with organic-inorganic silicone shell for battery thermal management

Microencapsulation is commonly adopted to improve the stability and expand the application of phase change materials. We developed a novel phase change microcapsule with MQ silicone resin (MQ), a typical organicinorganic hybrid polysiloxane, as its shell material through a simple preparation process. Its morphology, including its core-shell microstructure and size distribution, was observed via scanning electron microscopy, transmission electron microscopy, and laser diffraction particle size analysis. The microcapsule exhibited the best thermal properties and shape stability at a core-shell ratio of 2:1, where the thermal energy storage capacity was 80.21 kJ kg-1. It was then composited with silicone rubber (SR) to form a composite. Owing to the chemical structure of MQ, the microcapsule presented enhanced mechanical properties with the SR matrix. When the composite was used for battery thermal management of a commercial prismatic LiFePO4 battery at 1C, the maximum temperature could be reduced by more than 10 degrees C, and the maximum temperature difference could be controlled within 5 degrees C.