Integrated thermohydraulic analysis and RSM-based optimization of porous double-layer minichannel cold plates for lithium-ion battery cooling applications

The thermal safety limitations of lithium‑ion batteries remain a major challenge in high‑power electric‑vehicle applications. This study numerically evaluates a porous double‑layer minichannel battery thermal management system (BTMS) and examines five flow configurations under 1C–3C discharge rates. Three‑dimensional conjugate heat‑transfer simulations reveal that flow arrangement has minimal influence in clear channels, whereas porous channels exhibit strong configuration‑dependent behavior. Porous channels exhibit strong configuration‑dependent behavior; the porous–parallel design achieves the best cooling performance, reducing peak temperature to 32.7 °C and limiting temperature non‑uniformity to 7.6 °C. Although counter‑type configurations yield higher Nusselt numbers, they introduce significant thermal non‑uniformity. A Response Surface Methodology framework identifies porosity and Reynolds number as the dominant parameters governing thermohydraulic performance, with optimal conditions occurring near ε≈0.8 and Re≈300. Further balance analysis shows that significant temperature reduction is accompanied by increased hydraulic errors, while intermediate configurations partially compensate for these losses with limited thermal compromise. Trade‑off analysis further reveals that achieving an ∼11.5 K reduction in peak temperature requires nearly a fourfold increase in pressure drop, while intermediate configurations recover ∼34% of this penalty with minimal thermal compromise. The results provide a data‑driven guideline for designing high‑efficiency BTMS architectures capable of meeting the stringent thermal demands of next‑generation EV batteries.