NOVELTY - The bipolar plate (1, 1') for sandwich-like arrangement between two membrane-electrode units of a fuel- or electrolyte cell, comprises a base structure (2), which is made of a first material and in which a channel structure (11, 12, 13) open toward the surface, where the channel structure is implemented on each of the front faces facing away from each other and has a flow field with densely disposed channels, and a conductor structure integrated in the base structure and made of a conductive second material extending to the surface of both front faces of the base structure.    USE - Bipolar plate for sandwich-like arrangement between two membrane-electrode units of a fuel- or electrolyte cell.    ADVANTAGE - The bipolar plate can be economically, optimally, precisely and simply manufactured with less effort, high flexibility, desired geometry and good electrical resistance, and can be efficiently operated with long service life in harsh environmental conditions.    DETAILED DESCRIPTION - The bipolar plate (1, 1') for sandwich-like arrangement between two membrane-electrode units of a fuel- or electrolyte cell, comprises a base structure (2), which is made of a first material and in which a channel structure (11, 12, 13) open toward the surface, where the channel structure is implemented on each of the front faces facing away from each other and has a flow field with densely disposed channels, and a conductor structure integrated in the base structure and made of a conductive second material extending to the surface of both front faces of the base structure under the formation of surface electrical contact locations (19, 20, 21, 22, 23, 24) and creating an electrically conductive connection permeating the base structure between the contact locations implemented on the various front faces. The conductor structure comprises electrically conductive elements (3, 3', 4, 4', 5, 5', 6, 6', 7, 7', 8, 8'), which form a contact location on each front face with a terminating edge, where the contact locations are further located on the relevant front face of the bipolar plate within the flow field of the channel structure and are disposed between the channels of the channel structure and bounded by the material of the base structure. The base structure consists of plastic and is produced with an injection molding process, where the conductive elements are partially injection-molded as inserts by the plastic forming the base structure. The base structure consists of several plates connected with one another, whose separating planes lie between the both front faces of the bipolar plate. One of the conductive elements is produced as stamping part made of metal sheet, which uprightly penetrates the base structure from one front face to the other front face. A part of the conductive elements is flat plate elements. One of the conductive elements is produced from a wire section, which penetrates the bipolar plate from one front face to the other front face and provides a point- and/or circular-shaped contact location on each front face, is formed by solder, which is introduced into a hole or a slot through the bipolar plate in a flowable form, and protrudes around 10-150 mu m from the base structure surrounding it with its edge forming the respective contact location. The conductive elements have an electrically conductive protection coating, which is restricted at the area of the contact locations uncovered by the base structure. The conductive element forms the linear contact locations at the front face, where the contact locations are spaced apart from each other. The conductive structure consists of graphite, which is directly produced from the plastic of the base structure using a graphiting process after the production of the base structure consisting of plastic. A cooling channel and/or a heating pipe is arranged within the bipolar plate, where the cooling channel is flowed through by a coolant. The cooling channel is formed by a separate cooling tube, which is injection-molded as inserts with plastic. The base structure has a circumferential ridge-like elevation as sealing for the adjacent membrane-electrode units. An INDEPENDENT CLAIM is included for a fuel- or electrolyte cell stack or a fuel- or electrolyte cell module.    DESCRIPTION OF DRAWING(S) - The diagram shows a top view of a front side of a bipolar plate.    Bipolar plate (1, 1')    Base structure (2)    Conductive elements (3, 3', 4, 4', 5, 5', 6, 6', 7, 7', 8, 8')    Channel structure (11, 12, 13)    Contact locations. (19, 20, 21, 22, 23, 24)