NOVELTY - An electro-conductive plate assembly including a at least a first/cathode plate having a first flow field formed in it and defining a first flow channels (312) formed on its first major surface and a corresponding first set of lands on second major surface opposite first major surface, comprises: a first array of discrete flow disruptors (308) comprising a first set of flow disruptors adjacent a coolant inlet header (54), and a second set of flow disruptors extending obliquely into several parallel longitudinal channels.    USE - As an electro-conductive plate assembly for a fuel cell (claimed).    ADVANTAGE - The electro-conductive plate assembly provides two piece bipolar plate assembly having coolant flow field between. The configuration of various flow fields are such that plate assembly is formed of relatively thin material, and still supports required compressive loads of fuel cell stack. Each of pair of stamped plates has flow field on major outer surface to maximize contact area between major inner surfaces of plates, while allowing coolant to distribute and flow readily within coolant volume. The plate assembly provides much greater design flexibility in terms of flow field options; and provides an improvement in the gravimetric and volumetric power densities of a given fuel cell stack as well as significant material and cost savings. The bipolar plate assembly additionally includes a staggered seals between inlet margins, and integral manifolds to direct reactant gas and coolant flow through the fuel cell, where the seals less sensitive to tolerance variations.    DETAILED DESCRIPTION - An electro-conductive plate assembly including at least a first/cathode plate having a first flow field formed in it and defining a first flow channels (312) formed on its first major surface and a corresponding first set of lands on second major surface opposite first major surface, comprises: a first array of discrete flow disruptors (308) comprising a first set of flow disruptors adjacent a coolant inlet header (54), and a second set of flow disruptors extending obliquely into several parallel longitudinal channels. The electro-conductive plate assembly further comprises a second/anode plate juxtaposed to the first/cathode plate and has a second flow field formed in it that defines second flow channels on its third major surface and a corresponding second set of lands on a fourth major surface opposite the third major surface. Each of the first/cathode and second/anode plates have an inlet margin that includes a first reactant gas inlet header (46), a second reactant gas inlet header (50), and a coolant inlet header formed in it; and an exhaust margin that includes a first reactant gas outlet header (48), second reactant gas outlet header (52), and a coolant outlet header (56) formed in it, where the first flow field provides fluid communication between the first reactant gas inlet header and the first reactant gas outlet header, and the second flow field provides fluid communication between the second reactant gas inlet header and the second reactant gas outlet header; and the plate assembly further includes a third flow field (302) formed between the cathode and anode plates by contact between the first and second set of lands. The third flow filed includes the first array of discrete flow disruptors also formed by the first and second sets of lands also adjacent the coolant outlet header, and several parallel longitudinal channels formed by the first and second sets of lands between the first array of discrete flow disruptors and another one of the coolant inlet header and the coolant outlet header, and a fluid communication is established from the coolant inlet header through the third flow field to the coolant outlet header. The anode plate further comprises a second array of discrete flow disruptors interposed between the several parallel longitudinal channels and coolant outlet header (preferably adjacent the outlet header), and comprises a first set of discrete flow disruptors. The second array of discrete flow disruptors is present in a third flow field. The second array further comprises a second set of discrete flow disruptors extending obliquely into the several parallel longitudinal channels. Each of the first and second arrays further comprises a third set of discrete flow disruptors extending obliquely into the several parallel longitudinal channels in a direction opposite the second set of discrete flow disruptors. The electro-conductive plate assembly further comprises a first seal disposed on the first major surface of cathode plate and cooperating with it to provide a first fluid communication path between coolant inlet header formed in inlet margin and third flow field, and a second fluid communication path between third flow field and the coolant outlet header formed in the outlet margin; and a second seal disposed on the third major surface of anode plate and cooperating with it to provide a third fluid communication path between coolant inlet header formed in inlet margin and third flow field, and a fourth fluid communication path between third flow field and coolant outlet header formed in second margin. The electro-conductive plate assembly further comprises: first and second flow channels having an inlet leg that includes first longitudinal portion in fluid communication with one of the first and second reactant gas inlet headers and a first transverse portion adjacent the coolant inlet header, a serpentine leg that includes a first end in fluid communication with the first transverse portion, and an exhaust leg that includes a second transverse portion adjacent the coolant outlet header and in fluid communication with a second end of the serpentine leg, and a second longitudinal portion in fluid communication with the coolant outlet header; and first lands corresponding to one of the inlet legs and outlet legs of the first and second flow channels forming the first array of discrete flow disruptors; and second lands corresponding to the serpentine legs of the first and second flow channels forming several parallel longitudinal channels. The first and second transverse portions define first and second undulating flow channels respectively.    DESCRIPTION OF DRAWING(S) - The figure shows plan view showing contact areas at interface between anode and cathode plates plate assembly.    Second reactant gas/air inlet header (46)    Second reactant gas/air outlet header (48)    First reactant gas/hydrogen inlet header (50)    First reactant gas/hydrogen outlet header (52)    Coolant inlet header (54)    Coolant outlet header (56)    coolant flow field (302)    Array of discrete flow disruptors (308)    Flow channels (312)    Direction in which flow disruptors extend obliquely from area of coolant flow field adjacent coolant inlet header (314)    Direction in which flow disruptors extend obliquely towards coolant exhaust header (316)