Fuel-cell thermal management systems and control schemes therefore are disclosed. In one embodiment, the system may include a fuel-cell stack, a heat-exchanger, a thermal battery including a material having a melting temperature of 50-120° C., a first coolant loop including the fuel-cell stack and the thermal battery and excluding the heat-exchanger, and a second coolant loop including the fuel-cell stack, the thermal battery, and the heat-exchanger. The first and second coolant loops may be configured to heat and cool the fuel-cell stack, respectively. The system may include a controller or processor configured to direct coolant to transfer heat from the thermal battery to the fuel-cell stack based on a negative heat rejection status of the fuel-cell stack and to transfer heat from the fuel-cell stack to the thermal battery based on a positive heat rejection status of the fuel-cell stack when the thermal battery is below a target temperature.