Spatial and Temporal Temperature Homogenization in an Automotive Lithium-Ion Pouch Cell Battery Module

A battery system with a thermally optimized module design with regard to boundary conditions in automotive applications is developed. Measures for spatial and temporal temperature homogenization are realized. Highly thermal conductive pyrolytic graphite sheets as heat spreaders replace conventional metallic cooling sheets in a lightweight module design. Efficient space utilization with a novel phase change material for thermal peak-shaving enables benefits in thermal management and lifetime. Heat-conductive adhesives and elastomer-based gap filler sheets further reduce the thermal resistance and the rise in temperature. Measurements showed a maximum temperature difference between the cells of 4.3 K and a maximum thermal resistance between cells and coolant of 0.12 K/W. By integrating thermal solutions, the gravimetric and volumetric overhead was reduced by 25% and 10% compared to the state of the art.