The invention relates to a joint structure including a continuous joined section that joins together a pair of thin plates layered on each other so as to seal a space between the pair of the thin plates surrounded by the joined section, in which the joined section includes at least one continuous joining line which intersects plural times, and a plurality of spatial areas surrounded by two adjacent intersections of the joining line and the joining line connecting the two intersections.

The invention relates to an apparatus for monitoring the cell voltage of an individual cell (3), formed by a membrane electrode assembly (4) and bipolar plates (6), of a fuel cell stack (1), the apparatus having a measuring device (7) for each of the individual cells (3), which measuring device comprises an optical signal generator (9) which is controllable by the measuring device. The apparatus according to the invention is characterized in that the measuring device (7) is formed on a flexible circuit board that is connected to a frame (5) of a framed membrane electrode assembly (4, 5) or is formed as part of the frame.

The invention relates to an apparatus for monitoring the cell voltage of an individual cell (3), formed by a membrane electrode assembly (4) and bipolar plates (6), of a fuel cell stack (1), the apparatus having a measuring device (7) for each of the individual cells (3), which measuring device comprises an optical signal generator (9) which is controllable by the measuring device. The apparatus according to the invention is characterized in that the measuring device (7) is formed on a flexible circuit board that is connected to a frame (5) of a framed membrane electrode assembly (4, 5) or is formed as part of the frame.

An integrated electrode frame and preparation method and use thereof is provided. The integrated electrode frame includes a positive electrode frame, a negative electrode frame, and a membrane. Each of the positive electrode frame and the negative electrode frame is a flat plate with a central through-hole. The membrane is placed between the positive electrode frame and the negative electrode frame, and the membrane is located at the through-hole and hermetically connected to a peripheral edge of the through-hole. A peripheral edge of the positive electrode frame is hermetically connected to a peripheral edge of the negative electrode frame. A material composition of a connecting part of the positive electrode frame and the negative electrode frame contains at least one material which is the same as that of the positive electrode frame or the negative electrode frame. The structures and materials of the electrode frames and the membrane are optimized.

An integrated electrode frame and preparation method and use thereof is provided. The integrated electrode frame includes a positive electrode frame, a negative electrode frame, and a membrane. Each of the positive electrode frame and the negative electrode frame is a flat plate with a central through-hole. The membrane is placed between the positive electrode frame and the negative electrode frame, and the membrane is located at the through-hole and hermetically connected to a peripheral edge of the through-hole. A peripheral edge of the positive electrode frame is hermetically connected to a peripheral edge of the negative electrode frame. A material composition of a connecting part of the positive electrode frame and the negative electrode frame contains at least one material which is the same as that of the positive electrode frame or the negative electrode frame. The structures and materials of the electrode frames and the membrane are optimized.

A membrane electrode assembly for a fuel cell that includes a membrane electrode unit with a membrane and two electrodes which make surface contact with both faces of the membrane. The membrane electrode assembly has a seal support that surrounds the periphery of the membrane and that overlaps the latter. The membrane electrode also has a connecting layer which continuously overlaps the membrane and the seal support, an inner edge section of the connecting layer being bonded to the membrane electrode unit and an outer edge section of the connecting layer being bonded to the seal support on the same flat face of the connecting layer. A seal is connected outside the membrane to the seal support. A fuel cell is provided that includes a plurality of membrane electrode assemblies. A motor vehicle includes the fuel cell and a method is provided for producing the membrane electrode assembly.

A membrane electrode assembly for a fuel cell that includes a membrane electrode unit with a membrane and two electrodes which make surface contact with both faces of the membrane. The membrane electrode assembly has a seal support that surrounds the periphery of the membrane and that overlaps the latter. The membrane electrode also has a connecting layer which continuously overlaps the membrane and the seal support, an inner edge section of the connecting layer being bonded to the membrane electrode unit and an outer edge section of the connecting layer being bonded to the seal support on the same flat face of the connecting layer. A seal is connected outside the membrane to the seal support. A fuel cell is provided that includes a plurality of membrane electrode assemblies. A motor vehicle includes the fuel cell and a method is provided for producing the membrane electrode assembly.

An electrochemical arrangement with two metallic separator plates which each define a plate plane and which are stacked in a stack direction perpendicular to the plate planes. The separator plates comprise sealing elements which are embossed into the separator plate and which are supported against one another for sealing the electrochemical cell which is arranged between the separator plates and which are reversibly deformable in the stack direction up to a distance z.sub.2. The arrangement further comprises at least one support element which is arranged between the separator plates and which is distanced to the sealing elements of the separator plates in a direction parallel to the plate planes.

An electrochemical arrangement with two metallic separator plates which each define a plate plane and which are stacked in a stack direction perpendicular to the plate planes. The separator plates comprise sealing elements which are embossed into the separator plate and which are supported against one another for sealing the electrochemical cell which is arranged between the separator plates and which are reversibly deformable in the stack direction up to a distance z.sub.2. The arrangement further comprises at least one support element which is arranged between the separator plates and which is distanced to the sealing elements of the separator plates in a direction parallel to the plate planes.

Provided is a method for manufacturing a fuel cell stack that can manufacture the fuel cell stack efficiently, can improve the precision for joining and can improve the power generation efficiency. The method for manufacturing a fuel cell stack repeatedly stacks a separator, an electrode assembly and a separator in this order in accordance with the laminated structure of the fuel cell stack to be manufactured to manufacture the fuel cell stack. When the electrode assembly is stacked on the separator, the method pressurizes the electrode assembly stacked on the separator and applies laser light to the electrode assembly to join the resin frame of the electrode assembly to the separator. When the separator is stacked on the electrode assembly, the method pressurizes the separator stacked on the electrode assembly and applies laser light to the separator to join the separator to the resin frame of the electrode assembly.