Performance evaluation of a battery-cooling system using phase-change materials and heat pipes for electric vehicles under the short-circuited battery condition

Electrical vehicles equipped with lithium-ion batteries (LiBs) have been increasing in popularity on the market. LiBs have high energy density and high electric current; however, their lifetimes and performance are known to be strongly influenced by temperature rise due to heat generation, and thermal runaway may occur when the battery temperature exceeds 80 degrees C. Hence, the development of LiB thermal-management technology is essential. In this study, an A4-sized LiB was short circuited in a prototype cooling system with phase-change material (PCM) and heat pipes (HPs), and the performance of the cooling system was evaluated. To compare the cooling performances, four experimental conditions were adopted: a combination of PCM and HP; PCM only; HP only; and not using the cooling system. In addition, a simulation was conducted under the experimental conditions using a scale model of the cooling system. Thus, we confirmed that the temperature increase of the LiB, especially up to 80 degrees C, was extended by the effects of PCM. The combination of PCM and HP suppressed the temperature of LiB to be about 80 degrees C.