Studying carbon fiber composite phase change materials: Preparation method, thermal storage analysis and application of battery thermal management

Carbon fiber composite phase change material (PCM) can serve as an excellent material for thermal storage system. This work presents a new composite PCM prepared with two raw materials of KAl(SO4)2·12H2O (X) and Na2SO4·10H2O (Y), supporting materials activated carbon fibers (ACFs), and thermal conductivity agent nano carbon powder (C). The characterization results show that adding 1 wt% C can increase the thermal conductivity about 81.0 % of mixed materials (C, X, and Y) than that of mixed X, Y; Moreover, the addition of ACFs also increases the thermal conductivity by 130 %. DSC tests reveal that phase change temperatures of XY and CXY are respectively 36.47 °C and 35.67 °C, meantime the enthalpies are 220.84 J/g and 185.24 J/g, respectively. Thus, this new material is suitable for the lithium-ion battery thermal management system (BTMS) applying. The application results show that ACFs composited CXY (ACFs/CXY) tremendously cripples the battery's temperature rise rate after the melting point in comparison with no wrapping material, and the ACFs/CXY-based BTMS can effectively control the battery temperature below 60 °C for 1903 s at the high heating power of 6 W. The ACFs composite PCM has the advantages of low cost, simple preparation, and easy acquisition, which reduces the cost of energy storage system, and has remarkable capacity of temperature controlling.