Thermal Management Optimization of Thermoelectric Coolers with High-Conductivity Phase Change Materials

Thermoelectric coolers (TECs) are increasingly employed in electronics thermal management; however, their performance is often constrained by heat accumulation on the hot side. This study numerically investigates the integration of high-thermal-conductivity phase change materials (PCMs) into finned TEC sink cavities to enhance cooling stability and efficiency. Using COMSOL Multiphysics, the effects of PCM type (gallium vs. OM32), PCM height (1.5 mm and 3 mm), and input current (1.0, 1.2, and 1.4 ampere) were examined. Results show that gallium consistently outperforms OM32 in delaying temperature rise, extending the cooling phase, and sustaining higher coefficients of performance (COP). Increasing PCM height from 1.5 mm to 3 mm further prolonged the phase change period for both materials. At 1 ampere, gallium with a 3 mm height achieved the highest COP improvement (~ 50% over the baseline case, where no PCM) and the most prolonged low-temperature period. At 1.4 ampere, gallium reached the lowest cold-side temperature recorded (~ 278 K), although with a reduced COP due to accelerated melting and increased Joule heating. Overall, gallium-filled configurations demonstrated superior thermal buffering and efficiency retention across all tested conditions, confirming the potential of high-conductivity PCMs as an effective passive thermal management strategy for compact, energy-efficient electronics and energy systems.