Three-dimensional non-isothermal modeling of a phosphoric acid-doped polybenzimidazole (PBI) membrane fuel cell

► We numerically investigated the thermal behavior of a HT-PEMFC. ► We studied the location-specific heat source terms in the HT-PEMFC operation. ► Study reveals the impact of coolant temperature gradient on cell performance. ► Irreversible reaction heat accounts for 60-70% of the total waste heat released. ► This study helps to identify the optimal thermal management strategy for HT-PEMFC.