A fuel cell to provide a higher power density. The fuel cell can be produced by 3D printing in ceramic and has an improved power density by virtue of its spiral shape. In order to better extract the energy generated by the fuel cell, an interconnector sheet can be fastened positively to fastening knobs of the fuel cell by holding eyes. In addition, the interconnector sheet can be fixed by glass solder.

A fuel cell stack is provided that includes a top end plate, a bottom end plate, a plurality of fuel cells provided between the top end plate and the bottom end plate, at least one bipolar plate, a plurality of hollow fasteners, and a plurality of sleeves. Each of the at least one bipolar plate is formed between two of the plurality of fuel cells. The plurality of hollow fasteners and the plurality of sleeves extend through holes in each of the top end plate, the bottom end plate, the plurality of fuel cells and the at least one bipolar plate. Each of the plurality of sleeves surrounds one of the plurality of hollow fasteners. Each of the plurality of hollow fasteners comprises a top surface, a hole in the top surface, a side surface, and a plurality of holes formed in the side surface.

A fuel cell stack is provided that includes a top end plate, a bottom end plate, a plurality of fuel cells provided between the top end plate and the bottom end plate, at least one bipolar plate, a plurality of hollow fasteners, and a plurality of sleeves. Each of the at least one bipolar plate is formed between two of the plurality of fuel cells. The plurality of hollow fasteners and the plurality of sleeves extend through holes in each of the top end plate, the bottom end plate, the plurality of fuel cells and the at least one bipolar plate. Each of the plurality of sleeves surrounds one of the plurality of hollow fasteners. Each of the plurality of hollow fasteners comprises a top surface, a hole in the top surface, a side surface, and a plurality of holes formed in the side surface.

There is provided a fuel cell comprising a cell stacked body and a case configured to surround at least stacked body side faces of the cell stacked body. The case comprises a first case configured to include a first case side wall and a pair of first opposed side walls that are arranged to rise from a circumference of the first case side wall such as to have a draft angle; and a second case configured to include a second case side wall and a pair of second opposed side walls that are arranged to rise from a circumference of the second case side wall such as to have a draft angle. A first edge of each of the first opposed side walls is joined with a second edge of each of the second opposed side walls. This configuration suppresses size expansion of the fuel cell.

There is provided a fuel cell comprising a cell stacked body and a case configured to surround at least stacked body side faces of the cell stacked body. The case comprises a first case configured to include a first case side wall and a pair of first opposed side walls that are arranged to rise from a circumference of the first case side wall such as to have a draft angle; and a second case configured to include a second case side wall and a pair of second opposed side walls that are arranged to rise from a circumference of the second case side wall such as to have a draft angle. A first edge of each of the first opposed side walls is joined with a second edge of each of the second opposed side walls. This configuration suppresses size expansion of the fuel cell.

A channel forming system of fuel cell separator is provided. The channel forming system includes a composite molded body of graphite or graphite and resin that comprises the fuel cell separator; and a channel forming tool with rotary drive for the composite molded body. The channel forming tool includes a cylindrical body; and a grooving tool. The grooving tool includes machining blades in the shape of groove which are manufactured as workpiece shape of the channel and regularly arranged in lines on the external circumferential surface along the major axis of the cylindrical body, and as the channel forming tool rotates against the composite molded body, channels are created on the whole surface of one side of the composite molded body.

A channel forming system of fuel cell separator is provided. The channel forming system includes a composite molded body of graphite or graphite and resin that comprises the fuel cell separator; and a channel forming tool with rotary drive for the composite molded body. The channel forming tool includes a cylindrical body; and a grooving tool. The grooving tool includes machining blades in the shape of groove which are manufactured as workpiece shape of the channel and regularly arranged in lines on the external circumferential surface along the major axis of the cylindrical body, and as the channel forming tool rotates against the composite molded body, channels are created on the whole surface of one side of the composite molded body.

A fuel cell stack includes a fluid flow plate at an outer end, a sealing member contacting the fluid flow plate and a gas diffusion layer, and a catalyst layer inside the gas diffusion layer. A membrane is located at a central location between the catalyst layer and a second catalyst layer. The fluid flow plate includes a channel for receiving a portion of a perimeter of the gas diffusion layer.

A fixed die and a punch, which moves toward and away from the die, are provided. A series of bulges is formed in sheet metal between depressions and projections of the die and projections and depressions of the punch. In forming, the punch moves toward the die such that the sheet metal is pressed between first convex sections and second and third convex sections of the die and the punch, and subsequently the sheet metal is pressed between fourth convex sections.

A fixed die and a punch, which moves toward and away from the die, are provided. A series of bulges is formed in sheet metal between depressions and projections of the die and projections and depressions of the punch. In forming, the punch moves toward the die such that the sheet metal is pressed between first convex sections and second and third convex sections of the die and the punch, and subsequently the sheet metal is pressed between fourth convex sections.