US-12626932-B2 - Fuel cell separator member and fuel cell stack

US12626932B2US 12626932 B2US12626932 B2US 12626932B2US-12626932-B2

Abstract

A first positioning hole is formed in a first positioning portion of a separator member, which is a fuel cell separator member forming a fuel cell stack. The first positioning portion includes a reinforcing rib and a joint portion. The reinforcing rib extends linearly outside the first positioning hole and protrudes from each of a first metal separator and a second metal separator. The joint portion is located between the reinforcing rib and the first positioning hole, and the first metal separator and the second metal separator are joined together at the joint portion.

Inventors

Suguru OMORI
Yasuhiro Nagai

Assignees

HONDA MOTOR CO., LTD.

Dates

Publication Date: 20260512
Application Date: 20230509
Priority Date: 20220513

Claims (9)

1 . A fuel cell separator member comprising a joint separator that comprises a pair of metal separators joined together, the joint separator including an outer peripheral portion provided with a positioning portion configured to position a plurality of stack units in a direction orthogonal to a separator thickness direction when the stack units are stacked on each other, the stack units each including the joint separator and a membrane electrode assembly member, wherein the positioning portion is formed with a positioning hole formed by cutting out the outer peripheral portion of the joint separator so as to open toward an outside of the joint separator, and the positioning portion includes: a reinforcing rib extending linearly outside the positioning hole and protruding in the separator thickness direction from at least one of the pair of metal separators; and a joint portion located between the reinforcing rib and the positioning hole and configured to join together the pair of metal separators.
2 . The fuel cell separator member according to claim 1 , wherein the joint portion extends linearly along an outline of the positioning hole.
3 . The fuel cell separator member according to claim 2 , wherein the joint portion extends in a straight line shape or a wavy shape.
4 . The fuel cell separator member according to claim 3 , wherein the joint portion is provided in plurality between the reinforcing rib and the positioning hole.
5 . The fuel cell separator member according to claim 1 , wherein the positioning portion includes an additional rib located between the positioning hole and the reinforcing rib and protruding in the separator thickness direction from one of the pair of metal separators.
6 . The fuel cell separator member according to claim 1 , wherein the reinforcing rib includes: a rib body extending in a shape corresponding to an outline of the positioning hole; and an extending rib extending from the rib body toward the positioning hole.
7 . The fuel cell separator member according to claim 6 , wherein the extending rib is provided in plurality on the rib body, and the joint portion is located between the extending ribs adjacent to each other.
8 . A fuel cell stack comprising a stacked body that comprises a plurality of stack units stacked on each other, the stack units each including a membrane electrode assembly member and a separator member, wherein the separator member is a fuel cell separator member including a joint separator that comprises a pair of metal separators joined together, the joint separator including an outer peripheral portion provided with a positioning portion configured to position the stack units in a direction orthogonal to a separator thickness direction when the stack units are stacked on each other, the positioning portion is formed with a positioning hole formed by cutting out the outer peripheral portion of the joint separator so as to open toward an outside of the joint separator, and the positioning portion includes: a reinforcing rib extending linearly outside the positioning hole and protruding in the separator thickness direction from at least one of the pair of metal separators; and a joint portion located between the reinforcing rib and the positioning hole and configured to join together the pair of metal separators.
9 . A fuel cell stack comprising a stacked body that comprises a first membrane electrode assembly member, a first separator member, a second membrane electrode assembly member, and a second separator member that are stacked in this order, wherein each of the first separator member and the second separator member is a fuel cell separator member including a joint separator that comprises a pair of metal separators joined together, the joint separator including an outer peripheral portion provided with a positioning portion configured to position a plurality of stack units in a direction orthogonal to a separator thickness direction when the stack units are stacked on each other, the stack units each including the joint separator and the first membrane electrode assembly member or the second membrane electrode assembly member, the positioning portion is formed with a positioning hole formed by cutting out the outer peripheral portion of the joint separator so as to open toward an outside of the joint separator, the positioning portion includes: a reinforcing rib extending linearly outside the positioning hole and protruding in the separator thickness direction from at least one of the pair of metal separators; and a joint portion located between the reinforcing rib and the positioning hole and configured to join together the pair of metal separators, and wherein a cutout portion is formed in the outer peripheral portion of the joint separator, at a position adjacent to the positioning portion so as to open toward the outside of the joint separator, the cutout portion is larger than the positioning hole, and when viewed in a stacking direction of the first membrane electrode assembly member, the first separator member, the second membrane electrode assembly member, and the second separator member, an outline of the positioning hole of the first separator member is located inside an outline of the cutout portion of the second separator member, and an outline of the positioning hole of the second separator member is located inside an outline of the cutout portion of the first separator member.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS This application is based upon and claims the benefit of priority from Japanese Patent Application No. 2022-079144 filed on May 13, 2022, the contents of which are incorporated herein by reference. BACKGROUND OF THE INVENTION Field of the Invention The present invention relates to a fuel cell separator member and a fuel cell stack. Description of the Related Art In recent years, research and development have been conducted on fuel cells that contribute to energy efficiency in order to ensure that more people have access to affordable, reliable, sustainable and modern energy. The fuel cell stack includes a stacked body in which fuel cell separator members and MEA (membrane electrode assembly) members are alternately stacked. For example, JP 2013-196849 A discloses that, when MEA members and separator members are stacked, knock pins are passed through positioning holes formed in outer peripheral portions of the separator members to position the separator members in a direction orthogonal to a separator thickness direction. SUMMARY OF THE INVENTION However, in the related art as described above, there is a possibility that the outer peripheral portions of the separator members are deformed by the knock pins (positioning guides) coming into contact with the inner peripheral surfaces of the positioning holes. An object of the present invention is to solve the aforementioned problem. According to a first aspect of the present invention, there is provided a fuel cell separator member comprising a joint separator that comprises a pair of metal separators joined together, the joint separator including an outer peripheral portion provided with a positioning portion configured to position a plurality of stack units in a direction orthogonal to a separator thickness direction when the stack units are stacked on each other, the stack units each including the joint separator and a membrane electrode assembly member, wherein the positioning portion is formed with a positioning hole formed by cutting out the outer peripheral portion of the joint separator so as to open toward an outside of the joint separator, and the positioning portion includes: a reinforcing rib extending linearly outside the positioning hole and protruding in the separator thickness direction from at least one of the pair of metal separators; and a joint portion located between the reinforcing rib and the positioning hole and configured to join together the pair of metal separators. According to a second aspect of the present invention, there is provided a fuel cell stack comprising a stacked body that comprises a plurality of stack units stacked on each other, the stack units each including a membrane electrode assembly member and a separator member, wherein the separator member is the fuel cell separator member described above. According to a third aspect of the present invention, there is provided a fuel cell stack comprising a stacked body that comprises a first membrane electrode assembly member, a first separator member, a second membrane electrode assembly member, and a second separator member that are stacked in this order, wherein each of the first separator member and the second separator member is the fuel cell separator member described above, a cutout portion is formed in the outer peripheral portion of the joint separator, at a position adjacent to the positioning portion so as to open toward the outside of the joint separator, the cutout portion is larger than the positioning hole, and when viewed in a stacking direction of the first membrane electrode assembly member, the first separator member, the second membrane electrode assembly member, and the second separator member, an outline of the positioning hole of the first separator member is located inside an outline of the cutout portion of the second separator member, and an outline of the positioning hole of the second separator member is located inside an outline of the cutout portion of the first separator member. According to the present invention, when the plurality of stack units are stacked on each other, the separator members can be accurately positioned in the direction orthogonal to the separator thickness direction by inserting the positioning guides into the positioning holes. Further, since the positioning portions each include the reinforcing rib and the joint portion, it is possible to increase the rigidity of the positioning portion. As a result, even when the positioning guide comes into contact with the hole wall portion that forms the positioning hole, it is possible to suppress deformation of the positioning portion (the outer peripheral portion of the separator member). The above and other objects, features, and advantages of the present invention will become more apparent from the following description when taken in conjunction with the accompanying drawings, in which a preferred embodiment of the present invention is shown