Experimental investigation on incorporating wire mesh into phase change material-based battery packs at elevated ambient temperatures

• The mesh-PCM configuration shows 40% higher heat dissipation than the pure PCM case. • The mesh eliminates the need for latent energy usage for 5A and 10A at 22 °C. • The mesh integration extends the safe operation under 40 °C from 5A up to 15 A. • The mesh reduces the need for latent energy utilization by approximately 31–36 %. This paper presents a novel partial copper mesh integration in a phase change material (PCM)-based battery pack for nine series-connected 21700 lithium-ion cells (5000 mAh). The pack’s thermal behavior was investigated experimentally at discharge rates of 1C–6C (5 A–30 A) and ambient temperatures of 22 °C, 32 °C, and 42 °C. The novelty lies in embedding a partial copper wire mesh directly within the PCM. In addition, this research addresses scenarios where the ambient temperature reaches the PCM’s melting point, enabling evaluation of both positive and negative aspects of the ambient environment. Furthermore, a governing thermodynamics equation is developed, enabling quantification of PCM latent heat utilization by integrating experimentally measured heat generation, sensible energy absorption, and convective heat dissipation. This framework allows for a more accurate and theoretically grounded determination of the PCM melting fraction under varying thermal conditions. Results demonstrated improved thermal conductivity and a 40% average increase in heat dissipation at 22°C. At moderate discharge rates (1C–2C), the mesh-PCM configuration eliminated latent heat utilization and extended safe operation up to 3C (15 A). Under 5C–6C at moderate ambient temperatures, cell temperatures stabilized around 60 °C. Although elevated ambient temperatures introduce heat inflow, the mesh-PCM configuration transitioned faster to positive heat transfer compared to the pure PCM case. Nevertheless, at 1C and 42 °C, the mesh performed worse, transferring more heat from the hot environment into the system, highlighting the trade-off in increasing thermal conductivity. Overall, the partial mesh integration substantially enhances battery thermal management by reducing peak temperatures and enhancing heat dissipation without altering the airflow cooling system.