NOVELTY - The plate (2) has a sealing region (18) arranged between a perimeter region (16) and each of an active region (12) and a feed region (14). A set of outwardly extending tabs (22) is arranged adjacent to the perimeter region at each of two ends (4, 6) of the plate. A hinge region (20) is arranged between the perimeter region and the tabs at each of the ends of the plate, and extends from a side (8) of the plate to another side (10) of the plate and permits flexing of the tabs to connect with a peripheral electrical device (27) without undesirably flexing the sealing region of the plate.    USE - Bipolar plate for use in a fuel cell stack of a fuel cell system (all claimed) utilized as a power source for an electric vehicle.    ADVANTAGE - The plate has a widened boss and a narrow slot arrangement so as to improve an in-plane position control of the fuel cell stack. An opportunity for interference between the tabs and the electrical connectors during assembly of the fuel cell system is minimized. Excessive location variation is avoided by pairing a widened boss with a narrow slot, thus providing a single locating feature in the lateral direction, and avoiding redundant and potentially interfering constraints. The plate permits mating of the plate and the peripheral electrical devices despite variations in tolerances and stack repeat distance.    DETAILED DESCRIPTION - The fuel cell is a polymer electrolyte membrane (PEM) fuel cell. The peripheral electrical device is an embedded measurement module (EMM) board. INDEPENDENT CLAIMS are also included for the following:    (1) a fuel cell stack comprising a unitized electrode assembly    (2) a fuel cell system comprising a set of peripheral electrical devices.    DESCRIPTION OF DRAWING(S) - The drawing shows a top perspective view of a bipolar plate.    Bipolar plate (2)    Ends of the plate (4, 6)    Sides of the plate (8, 10)    Active region (12)    Feed region (14)    Perimeter region (16)    Sealing region (18)    Hinge region (20)    Outwardly extending tabs (22)    Peripheral electrical device (27)