A novel elastomeric copolymer-based phase change material with thermally induced flexible and shape-stable performance for prismatic battery module

Abstract

In this study, a novel thermally induced flexible phase change material (PCM), which consists of an elastomeric block copolymer called styrene-b-ethylene-co-butylene-b-styrene triblock copolymer (SEBS), paraffin (PA) and expanded graphite (EG), is successfully prepared. Here, SEBS and EG serve as a supporting material and a thermal enhanced component. The effects related to latent heat, thermal stability, thermal conductivity and shape stability of different SEBS mass fractions are investigated and the test results reveal the good thermal performance of the PA/SEBS/EG blends. Besides, the further rheological analysis points out that the property of shape stability and thermal induced flexibility are based on the physical crosslinking mechanism between SEBS and PA. As a result, PA/SEBS/EG composite considerably reduces thermal contact resistance due to narrower gap, endowing the battery module with much better heat dissipation efficiency and temperature uniformity. The 3 C discharge of the battery module test shows that the maximum temperature of battery module using PA/SEBS/EG blend is effectively controlled within 42.2 °C, while the maximum temperature difference is below the safety threshold of 5 °C during the 5-cycling discharge and charge tests.