CN-122000404-A - Fuel cell stack

Abstract

The invention provides a technology capable of inhibiting damage of a fuel cell unit. The anode separator and the cathode separator each include a main body portion having a1 st welded portion and a2 nd welded portion formed by welding the anode separator and the cathode separator of fuel cells adjacent to each other in the stacking direction of the plurality of fuel cells, a main rib portion protruding from the main body portion between the 1 st welded portion and the 2 nd welded portion so as to be separated from the adjacent fuel cells in the stacking direction, and at least one additional rib portion of the 1 st additional rib portion and the 2 nd additional rib portion protruding from the main body portion between the main rib portion and the 1 st welded portion so as to be separated from the adjacent fuel cells in the stacking direction at a distance from the main rib portion, and the 2 nd additional rib portion protruding from the main body portion between the main rib portion and the 2 nd welded portion so as to be separated from the adjacent fuel cells at a distance from the main rib portion in the stacking direction.

Inventors

• SHIBATA KAZUNORI
• MATSUBARA NAOHIRO

Assignees

• 丰田自动车株式会社

Dates

Publication Date

20260508

Application Date

20251029

Priority Date

20241101

Claims (5)

1. 1. A fuel cell stack in which a plurality of fuel cell units are stacked, characterized in that, The plurality of fuel cell units each include: Membrane electrode gas diffusion layer assembly, and An anode separator and a cathode separator sandwiching the membrane electrode gas diffusion layer assembly, The anode separator and the cathode separator are each provided with: A main body portion having a1 st welded portion formed by welding the anode separator and the cathode separator of the fuel cell unit adjacent to each other in the stacking direction of the plurality of fuel cell units, and a2 nd welded portion formed by welding the anode separator and the cathode separator of the adjacent fuel cell unit with a space from the 1 st welded portion; a main rib portion protruding from the main body portion between the 1 st welded portion and the 2 nd welded portion so as to be separated from the adjacent fuel cell unit in the stacking direction, thereby forming a flow path through which a coolant flows between the anode separator and the cathode separator of the adjacent fuel cell unit, and At least one additional rib of a1 st additional rib and a2 nd additional rib, the 1 st additional rib protruding from the main body portion between the main rib and the 1 st weld so as to be spaced apart from the main rib and separate from the adjacent fuel cell unit in the stacking direction, and the 2 nd additional rib protruding from the main body portion between the main rib and the 2 nd weld so as to be spaced apart from the main rib and separate from the adjacent fuel cell unit in the stacking direction.
2. 2. The fuel cell stack according to claim 1, wherein, The height of the additional rib is less than half the height of the main rib.
3. 3. The fuel cell stack according to claim 1, wherein, The shape of the additional rib is a plane-symmetrical shape having a plane along the stacking direction and the extending direction of the additional rib as a symmetry plane.
4. 4. The fuel cell stack according to claim 1, wherein, The main rib has a flat portion forming the top of the main rib, The distance separating the additional rib from the main rib is equal to or less than the width of the flat portion.
5. 5. The fuel cell stack according to claim 1, wherein, The radius of curvature of the connection portion between the additional rib portion and the main body portion is 0.5 or more.

Description

Fuel cell stack Technical Field The present invention relates to a fuel cell stack. Background Conventionally, a fuel cell stack is known in which a plurality of fuel cells including a membrane electrode gas diffusion layer assembly and an anode separator and a cathode separator sandwiching the membrane electrode gas diffusion layer assembly are stacked (patent document 1). In this technique, a flow path through which a coolant flows is formed between the anode separator and the cathode separator of adjacent fuel cell units by ribs provided on the anode separator and the cathode separator, respectively. Further, the anode separator and the cathode separator of adjacent fuel cell units are welded at both ends of the rib. Patent document 1 Japanese patent laid-open No. 2007-311069 Disclosure of Invention In a fuel cell stack, a load is sometimes applied in the stacking direction of a plurality of fuel cell units. When a load is applied to the fuel cell in the stacking direction, stress concentration occurs from the connection portion between the rib and the separator main body to the welded portion, and the separator may be broken, the separator may be plastically deformed, the welded portion may be peeled off, or the like, to damage the fuel cell. The present invention can be implemented in the following manner. (1) According to one aspect of the present invention, a fuel cell stack is provided. In a fuel cell stack in which a plurality of fuel cells are stacked, each of the plurality of fuel cells includes a membrane electrode gas diffusion layer joined body, an anode separator and a cathode separator sandwiching the membrane electrode gas diffusion layer joined body, each of the anode separator and the cathode separator includes a main body portion having a1 st welded portion welded to the anode separator and the cathode separator of the adjacent fuel cell cells in a stacking direction of the plurality of fuel cells, a2 nd welded portion welded to the 1 st welded portion at a distance from the anode separator and the cathode separator of the adjacent fuel cell cells, a main rib portion protruding from the main body portion in a manner separated from the adjacent fuel cell cells in the stacking direction between the 1 st welded portion and the 2 nd welded portion, thereby forming a flow path for flowing a cooling liquid between the anode separator and the cathode separator of the adjacent fuel cell cells, and a2 nd welded portion added to the main body portion in a manner separated from the main body portion in the stacking direction between the 1 st welded portion and the 2 nd welded portion, and at least one of the additional rib portions added in a manner separated from the main body portion between the main body portion and the main body portion in the stacking direction between the adjacent rib portion and the main rib portion in which the main rib portion is added. According to this aspect, the anode separator and the cathode separator each have an additional rib in a region between the main rib and the welded portion, the region being a region where stress tends to concentrate when a load is applied to the fuel cell in the stacking direction. In this way, the stress generated in the separator by applying a load to the fuel cell in the stacking direction can be released from the main rib side to the additional rib side. Accordingly, when a load is applied to the fuel cell unit in the stacking direction, stress concentration from the connection portion between the main rib portion and the welded portion to the welded portion can be avoided. Therefore, breakage of the fuel cell unit due to breakage of the separator, plastic deformation of the separator, separation of the welded portion, or the like can be suppressed. (2) In the above aspect, the height of the additional rib may be equal to or less than half the height of the main rib. According to this aspect, by setting the height of the additional rib to be equal to or less than half the height of the main rib, the stress can be released more reliably from the main rib side toward the additional rib side. Accordingly, when a load is applied to the fuel cell unit in the stacking direction, stress concentration from the connection portion between the main rib portion and the welded portion to the welded portion can be more reliably avoided. Therefore, breakage of the fuel cell unit can be more reliably suppressed. (3) In the above aspect, the shape of the additional rib may be a plane-symmetrical shape having a plane along the stacking direction and the extending direction of the additional rib as a symmetry plane. According to this aspect, the shape of the additional rib is formed to be symmetrical with respect to the plane along the stacking direction of the fuel cell and the extending direction of the additional rib, so that the stress can be more reliably released from the main rib side toward the additional rib side. Accordingly, when a load is app