Patent ID: 8158299

Claim:
A bipolar plate; for a fuel cell stack, said bipolar plate comprising: at least a cathode-side sub-plate and an anode-side sub-plate which are arranged parallel to each other, with upper and bottom sides that are located externally, and an interior that is enclosed by the sub-plates; a fluid port area arranged at an extremity of said bipolar plate, with at least one fluid port, over which a fluid can be conveyed to fluid channels, arranged on at least one of the sides; a manifold zone disposed between the fluid port area and the fluid channels, over which said fluid can be distributed to fluid channels assigned thereto; and an accumulation zone through which the fluid can be conveyed from the fluid channels to another fluid port area; wherein, in at least one of the manifold zone and in the accumulation zone, at least one of the sub-plates has an arrangement of positive and negative support points, said positive support points being formed as raised areas in said at least one of said sub-plates, and said negative support points being formed as depressions and having an orientation opposite to that of the positive support points; said support points have an elongated approximately elliptical cross section; adjacent pairs of positive support points are aligned transversely to the fluid channels; a longitudinally aligned negative support point is formed between each adjacent pair of positive support points and connects said adjacent pair of positive supports together; and in an assembled state of said bipolar plate said negative support points form free spaces between the positive support points for accommodating fluid flow.