Method for producing a bipolar plate strand, method for producing a bipolar plate, and device for implementing the method

A method for producing a bipolar plate of a fuel cell, comprising:

• providing of a first unipolar plate and a second unipolar plate, the unipolar plates comprising a plurality of at least preformed webs and a plurality of at least preformed ducts running between every two adjacent webs;
• moving of the unipolar plates in the direction of a roll gap of a roll pair provided with roll structures of a rolling device;
• sending of a laser beam of a laser device onto a rotating mirrored polygon wheel, the laser beam being directed at a plurality of individual positions of a surface of one or both of the unipolar plates to heat the individual positions immediately before or upon entry of the unipolar plates in the roll gap;
• and
• joining of the unipolar plates at least at one of the individual positions of the surface to form a bipolar plate upon transporting of the unipolar plates through the roll gap under the action of pressure.

A device for producing a bipolar plate of a fuel cell by a method including:

• providing of a first unipolar plate and a second unipolar plate, the unipolar plates comprising a plurality of at least preformed webs and a plurality of at least preformed ducts running between every two adjacent webs, moving of the unipolar plates in the direction of a roll gap of a roll pair provided with roll structures of a rolling device, sending of a laser beam of a laser device onto a rotating mirrored polygon wheel, the laser beam being directed at a plurality of individual positions of a surface of one or both of the unipolar plates to heat the individual positions immediately before or upon entry of the unipolar plates in the roll gap, and joining of the unipolar plates at least at one of the individual positions of the surface to form a bipolar plate upon transporting of the unipolar plates through the roll gap under the action of pressure, the device comprising:
• a laser device, which is designed to heat by at least one laser beam at least one surface region of a surface of one or both of the two unipolar plates, there being present a rolling device having a roll pair forming a roll gap between them,
• wherein the rolls of the roll pair are provided with a roll structure, which is designed to press a plurality of surface regions of the two unipolar plates heated during their transport through the roll gap such that the two unipolar plates are joined to form a bipolar plate at the surface regions, wherein the laser device is associated with at least one mirrored polygon wheel driven in rotation, such that the laser beam is directed at a plurality of individual positions of the surface of one or both of the unipolar plates and the individual positions are thus heated immediately before or during the entry of the unipolar plates in the roll gap.