Analytical and numerical modeling of phase change material and hybrid PCM-heat sinks for high-power wireless EV charging

With the growing need of electrifying the transportation industry, high-power electric vehicle (EV) charging stations will play an instrumental role. This study focuses on passive thermal management designs using phase change materials (PCM) to transfer 1 MW of electrical power to heavy-duty vehicles within a 35-min timeframe. Various heat sink configurations and hybrid PCM are numerically investigated for effective heat dissipation during charging. Integration of a three-type hybrid PCM with a heat sink results in a 7.3% reduction in final surface temperature compared to a single PCM integrated with a heat sink. Using diverse PCMs, especially in a Hybrid PCM system with multiple melting points, offers superior surface temperature control. Furthermore, a 1D transient analytical model is developed for PCM-only design, which presents a baseline performance and is used to validate the corresponding numerical model. In this model, similarity method is utilized under two distinct boundary conditions, i.e., constant temperature, and heat flux conditions. Comparative assessment with corresponding numerical model reveals minimal surface temperature differences of 0.47% and 0.66% for constant temperature and heat flux cases, respectively. It provides valuable insights into passive thermal management systems using PCMs as potential solutions to high-power EV charging systems.