Investigation on Liquid Cooling of Lithium-Based Batteries in Phase Change Materials Using Metal Foams: A Numerical Approach

Abstract

Abstract. This numerical study proposes a hybrid cooling system design that constructs both phase change materials (PCM), which are embedded with metal foams of different morphological features and liquid cooling channels around a lithium-polymer battery. The battery is discharged at three different C-rates. The study incorporates the change of the internal resistance with respect to depth of discharge and temperature using the Generalized Reduced Gradient Algorithm, using experimental analysis. The model is implemented using the finite volume method. Results show that increasing C-rate raises both battery and PCM temperatures. The highest surface temperatures were recorded for RT35 with 40 PPI, closely matched by RT25HC with 40 PPI (ɛ = 0.9659), indicating similar heat retention at high porosity. Conversely, the lowest surface temperatures occurred with RT35 at 20 PPI (ɛ = 0.949), nearly identical to RT25HC at 20 PPI, confirming that low-porosity foams enhance thermal conductivity and cooling efficiency. PCM temperature trends mirrored the surface data, with RT35–20PPI consistently yielding the lowest values. For both PCMs, 20 PPI foams exhibited up to ∼0.1% lower maximum surface temperatures compared to 40 PPI foams, attributed to higher effective thermal conductivity at lower porosity. RT35 generally outperformed RT25HC by maintaining ∼0.05–0.1% cooler PCM temperatures under identical conditions, especially at low porosity. Across all configurations, the maximum temperature of the full battery volume was consistently 0.01–0.02% higher than its surface, reflecting internal heat generation dynamics. These results quantitatively demonstrate the influence of PCM type, foam porosity, and discharge rate on passive thermal management, offering a validated experimental–numerical framework for optimizing PCM–metal foam composites in battery cooling applications.