Bipolar plate, intended to be positioned between two electrodes (3, 4) of adjacent electrochemical cells, including a first conductive sheet and a second conductive sheet (10, 20) each having an inner face (12, 22) and an outer face (11, 21), the conductive sheets (10, 20) being bonded to one another by the inner faces (12, 22), and each including reliefs at least partially delimiting, - on the outer faces (11, 21), distribution channels (Ca, Cc) that are intended to distribute reactive gases, the distribution channels (Ca, Cc) of one and the same conductive sheet (10, 20) being separated pairwise by a dividing rib (Na, Nc) intended to make contact with one of said electrodes (3, 4), and - on the inner faces (12, 22), cooling channels (Cr) that are intended to allow the flow of a heat-transfer fluid; characterized in that each of said distribution channels (Ca, Cc) is located facing a dividing rib (Nc, Na) of the opposite conductive sheet (10, 20); and in that said distribution channels (Ca, Cc) include portions of various depths (Sa, Da; Sc, Dc) that are arranged so as to form a longitudinal alternation between: - a first zone, referred to as an enhanced distribution zone, in which: o the distribution channels (Ca, Cc) have a combined cross section of a first value, referred to as a high distribution value, and o the cooling channels (Cr) have a combined cross section of a first value, referred to as a low cooling value; and - a second zone, referred to as an enhanced cooling zone, in which: o the distribution channels (Ca, Cc) have a combined cross section of a value that is lower than the high distribution value, and o the cooling channels (Cr) have a combined cross section of a value that is higher than the low cooling value. - on the outer faces (11, 21), distribution channels (Ca, Cc) that are intended to distribute reactive gases, the distribution channels (Ca, Cc) of one and the same conductive sheet (10, 20) being separated pairwise by a dividing rib (Na, Nc) intended to make contact with one of said electrodes (3, 4), and - on the inner faces (12, 22), cooling channels (Cr) that are intended to allow the flow of a heat-transfer fluid; - a first zone, referred to as an enhanced distribution zone, in which: o the distribution channels (Ca, Cc) have a combined cross section of a first value, referred to as a high distribution value, and o the cooling channels (Cr) have a combined cross section of a first value, referred to as a low cooling value; and o the distribution channels (Ca, Cc) have a combined cross section of a first value, referred to as a high distribution value, and o the cooling channels (Cr) have a combined cross section of a first value, referred to as a low cooling value; and - a second zone, referred to as an enhanced cooling zone, in which: o the distribution channels (Ca, Cc) have a combined cross section of a value that is lower than the high distribution value, and o the cooling channels (Cr) have a combined cross section of a value that is higher than the low cooling value. o the distribution channels (Ca, Cc) have a combined cross section of a value that is lower than the high distribution value, and o the cooling channels (Cr) have a combined cross section of a value that is higher than the low cooling value.