A bipolar plate, intended to be located between and in contact with an anode and a cathode of two electrochemical cells, including two conductive sheets (13a, 13c) placed side by side including anode and cathode distribution circuits, the bipolar plate having a constant thickness (E ch) in a zone including at least one of the homogenisation circuits (20a, 20c), including: ∘ anode and cathode distribution circuits, to provision said anode and cathode with reactive gases, superimposed on each other, extending longitudinally between first and second ends (14.1, 14.2) opposite to each other, defined by reliefs of the conductive sheets (13a, 13c); and a cooling circuit defined by an inner space located between the conductive sheets (13a, 13c); ∘ anode and cathode collectors for injecting reactive gases or collecting fluids, and a collector for a coolant, located facing the first ends (14a.1, 14c.1); ∘ the anode and cathode homogenisation circuits, each including homogenisation channels (21a, 21c) ensuring fluid connection between one of the anode and cathode collectors and the first corresponding end (14a.1, 14c.1), partially superimposed on each other, so that there are defined: • a first anode Z1a, resp. cathode Z1c zone, only including the anode, resp. cathode homogenisation circuit, the homogenisation channels (21a, 21c) of which open onto the anode, resp. cathode collector; • a second zone Z2 in which the homogenisation circuits (20a, 20c) are superimposed on each other, the anode, resp. cathode homogenisation channels opening onto the anode, resp. cathode distribution circuit, and having an anode Pa n, resp. cathode Pc n nominal depth; ∘ characterised in that, in at least one of the first anode Z1a and cathode Z1c zones, at least a part of the homogenisation channels (21a, 21c) has, on at least a part of their length, a depth Pa 1, Pc 1 greater than the corresponding nominal depth Pa n, Pc n. ∘ anode and cathode distribution circuits, to provision said anode and cathode with reactive gases, superimposed on each other, extending longitudinally between first and second ends (14.1, 14.2) opposite to each other, defined by reliefs of the conductive sheets (13a, 13c); and a cooling circuit defined by an inner space located between the conductive sheets (13a, 13c); ∘ anode and cathode collectors for injecting reactive gases or collecting fluids, and a collector for a coolant, located facing the first ends (14a.1, 14c.1); ∘ the anode and cathode homogenisation circuits, each including homogenisation channels (21a, 21c) ensuring fluid connection between one of the anode and cathode collectors and the first corresponding end (14a.1, 14c.1), partially superimposed on each other, so that there are defined: • a first anode Z1a, resp. cathode Z1c zone, only including the anode, resp. cathode homogenisation circuit, the homogenisation channels (21a, 21c) of which open onto the anode, resp. cathode collector; • a second zone Z2 in which the homogenisation circuits (20a, 20c) are superimposed on each other, the anode, resp. cathode homogenisation channels opening onto the anode, resp. cathode distribution circuit, and having an anode Pa n, resp. cathode Pc n nominal depth; • a first anode Z1a, resp. cathode Z1c zone, only including the anode, resp. cathode homogenisation circuit, the homogenisation channels (21a, 21c) of which open onto the anode, resp. cathode collector; • a second zone Z2 in which the homogenisation circuits (20a, 20c) are superimposed on each other, the anode, resp. cathode homogenisation channels opening onto the anode, resp. cathode distribution circuit, and having an anode Pa n, resp. cathode Pc n nominal depth; ∘ characterised in that, in at least one of the first anode Z1a and cathode Z1c zones, at least a part of the homogenisation channels (21a, 21c) has, on at least a part of their length, a depth Pa 1, Pc 1 greater than the corresponding nominal depth Pa n, Pc n.