A fuel cell including a stack of electrochemical cells and end plates applying a tightening strain onto the electrochemical cells, a thermal management system formed by a heat transfer fluid flow circuit in the stack, and a heat transfer fluid flow circuit external to the stack. The heat transfer flow circuit and the external circuit are connected in one of the end plates. The external circuit includes a first subcircuit including a heat exchanger and a second subcircuit directly connected to the inlet of the internal circuit. A thermostatic valve Is integrated in the end plate to control the heat transfer fluid flow in one and/or the other of the subcircuits as a function of temperature of the fluid at the outlet of the internal circuit.