Laminated structure of fuel cell separator

Abstract

The invention provides a laminated structure of a fuel cell separator, which is capable of ensuring a stable reaction force by using an opposite bearing part and effectively inhibiting over-compression of a convex rib part even if the laminated separator is arranged in an offset manner. The present invention is provided with a first group (11) having one separator (12) and a second group (21) having another separator (22), the one separator (12) and the other separator (22) each having a bead portion (14, 24) and a receiving portion (16, 26) for receiving an overcompression load of the respective bead portion (14, 24), the one separator (12) and the other separator (22) being disposed so that the surfaces of the bead portion (14, 24) and the receiving portion (16, 26) on the protruding side face each other. The direction in which the receiving section (26) of one separator (12) extends linearly is not parallel to the direction in which the receiving section (26) of the other separator (22) extends linearly, and the receiving sections (16, 26) that face each other partially overlap each other.

Description

Technical Field

[0001] The present invention relates to a laminated structure of fuel cell separators. More specifically, it relates to a laminated structure of fuel cell separators in which two or more fuel cell separators are laminated. Background Art

[0002] In recent years, fuel cells (i.e., fuel cell stacks) have been developed for fuel cell vehicles and the like. The fuel cell stack includes a laminated structure in which a plurality of unit cells are laminated and a housing that houses the laminated structure. And, the unit cell has an electrolyte membrane, electrodes, gas flow paths, fuel cell separators, etc. as main structural components, and has a structure in which a fuel gas such as hydrogen is supplied from the anode side and an oxidizing gas such as air is supplied from the cathode side for power generation.

[0003] One of the sealing structures of fuel cells is a structure that ensures sealing by the reaction force of the rib portions (for example, refer to Figure 2 and Figure 3 etc.). For example, in Patent Document 1, a fuel cell is disclosed, which includes: a membrane electrode gas diffusion layer assembly in which a membrane electrode assembly is sandwiched between a pair of gas diffusion layers; a frame-shaped insulating member that abuts against the outer peripheral portion of the membrane electrode gas diffusion layer assembly; and first and second separators that sandwich the membrane electrode gas diffusion layer assembly and the insulating member.

[0004] However, when the separators having the above-described sealing structure are laminated and compressed, the compression states of the respective rib portions are uneven, and a part of the rib portions are over-compressed and damaged, resulting in impaired sealing performance of the fuel cell.

[0005] As a countermeasure for preventing such over-compression of the rib portions, a technique has been proposed in which a receiving portion for preventing over-compression of the rib portions is provided around the rib portions of the separator (for example, refer to Patent Document 2). For example, in Patent Document 2, a fuel cell stack assembly including at least one bipolar plate is disclosed, and the bipolar plate includes at least one raised rib portion and at least one raised stopper. In the fuel cell stack assembly described in Patent Document 2, the above-described raised stopper functions as a receiving portion for preventing over-compression of the rib portion, and by adding such a stopper, excessive compression can be prevented, and leakage in the fuel cell and failure of the fuel cell stack can be suppressed.

[0006] Prior Art Documents

[0007] Patent Documents

[0008] Patent Document 1: Japanese Patent Application Laid-Open No. 2020-198200

[0009] Patent Document 2: Specification of U.S. Patent Application Publication No. 2018 / 0123141 Summary of the Invention

[0010] Technical Problem to be Solved by the Invention

[0011] However, even if a receiving portion for preventing over-compression of the rib portion is provided around the rib portion, if a setting deviation occurs during the stacking of the separators (for example, a positional deviation between the stacked separators), there will be a problem that it is difficult to suppress over-compression of the rib portion.

[0012] For example, as a receiving portion for preventing over-compression of the rib portion, a protruding receiving portion provided around the rib portion can be cited. Such a receiving portion receives over-compression of the rib portion using the uppermost surface of the protruding receiving portion. Therefore, for example, when the uppermost surface of the receiving portion is arc-shaped, the center side of the uppermost surface becomes a high reaction force portion, but when a setting deviation occurs during the stacking of the separators, the high reaction force portions (that is, the center side of the uppermost surface) of the opposing receiving portions do not contact each other, and the reaction force of the receiving portion decreases. In addition, when the uppermost surface of the receiving portion is flat, both end sides of the flat uppermost surface become high reaction force portions, but when a setting deviation occurs during the stacking of the separators, as in the above case, the high reaction force portions of the opposing receiving portions do not contact each other, and the reaction force of the receiving portion decreases. It should be noted that although it is also considered to stack the separators in a manner that avoids setting deviation to suppress the decrease in the reaction force of the receiving portion, very high precision is required during the stacking of the separators. For example, from the viewpoint of the performance of the fuel cell, assembly precision higher than the required assembly precision may also be required.

[0013] Regarding such problems, there is an urgent need to develop a stacked structure of fuel cell separators with excellent robustness, which can maintain a good contact state between opposing receiving portions even when a setting deviation occurs in the separators, and can effectively prevent over-compression of the rib portion through contact between the receiving portions.

[0014] In view of the above problems, according to the present invention, there is provided a stacked structure of fuel cell separators that effectively suppresses performance degradation caused by external influences such as setting deviation of the separators and has excellent robustness.

[0015] Solutions for Solving Technical Problems

[0016] To solve the above problems, the present invention provides the following stacked structure of fuel cell separators.

[0017] [1] A stacked structure of fuel cell separators is a stacked structure of two or more fuel cell separators that form a unit cell of a fuel cell stack. Among them,

[0018] The stacked structure of the fuel cell separators includes: a first group having one separator; and a second group having another separator.

[0019] The one separator and the another separator each have: a rib portion protruding toward one surface side; and a bearing portion protruding linearly in the same direction as the rib portion and for receiving the over-compression load of the rib portion.

[0020] The one separator and the another separator are relatively arranged in such a manner that the surfaces on the side where the rib portion and the bearing portion protrude face each other.

[0021] The direction in which the bearing portion of the one separator extends linearly and the direction in which the bearing portion of the another separator extends linearly are configured to be non-parallel, and a part of the opposing bearing portions overlap each other.

[0022] [2] The stacked structure of the fuel cell separators according to [1], which includes: the first group composed of a first separator and a second separator stacked in the plate thickness direction; and

[0023] The second group composed of a third separator and a fourth separator stacked in the plate thickness direction.

[0024] The second separator has: a second rib portion protruding toward the second outer surface side opposite to the first contact surface where the stacked first separator and second separator are in contact; and a second bearing portion protruding linearly in the same direction as the second rib portion and for receiving the over-compression load of the second rib portion.

[0025] The third separator has: a third rib portion protruding toward the third outer surface side opposite to the second contact surface where the stacked third separator and fourth separator are in contact; and a third bearing portion protruding linearly in the same direction as the third rib portion and for receiving the over-compression load of the third rib portion.

[0026] The first group and the second group are stacked in such a manner that the second outer surface side of the second separator constituting the first group faces the third outer surface of the third separator constituting the second group.

[0027] The direction in which the second bearing portion of the second separator extends linearly and the direction in which the third bearing portion of the third separator extends linearly are configured to be non-parallel, and they are relatively arranged in such a manner that a part of the second bearing portion and the third bearing portion overlap each other.

[0028] [3] The stacked structure of fuel cell separators described in [2], wherein the first separator has: a first rib portion protruding toward the first outer surface side opposite to the first contact surface; and a first receiving portion protruding linearly in the same direction as the first rib portion and for receiving the over-compression load of the first rib portion.

[0029] The direction in which the first receiving portion of the first separator extends linearly is configured to be parallel to the direction in which the second receiving portion of the second separator extends linearly.

[0030] [4] The stacked structure of fuel cell separators described in [3], wherein the first receiving portion and the second receiving portion are formed to be mirror-symmetrical with respect to the first contact surface.

[0031] [5] The stacked structure of fuel cell separators described in [2], wherein the fourth separator has: a fourth rib portion protruding toward the fourth outer surface side opposite to the second contact surface; and a fourth receiving portion protruding linearly in the same direction as the fourth rib portion and for receiving the over-compression load of the fourth rib portion.

[0032] The direction in which the third receiving portion of the third separator extends linearly is configured to be parallel to the direction in which the fourth receiving portion of the fourth separator extends linearly.

[0033] [6] The stacked structure of fuel cell separators described in [5], wherein the third receiving portion and the fourth receiving portion are formed to be mirror-symmetrical with respect to the second contact surface.

[0034] [7] The stacked structure of fuel cell separators described in [2], wherein the first separator has: a first rib portion protruding toward the first outer surface side opposite to the first contact surface; and a first receiving portion protruding linearly in the same direction as the first rib portion and for receiving the over-compression load of the first rib portion.

[0035] The direction in which the first receiving portion of the first separator extends linearly is configured to be non-parallel to the direction in which the second receiving portion of the second separator extends linearly.

[0036] [8] The stacked structure of fuel cell separators described in [7], wherein the direction in which the first receiving portion of the first separator extends linearly is configured to be parallel to the direction in which the third receiving portion of the third separator extends linearly.

[0037] [9]The stacked structure of fuel cell separators according to [2] above, wherein the fourth separator has: a fourth rib portion protruding toward the fourth outer surface side opposite to the second abutting surface; and a fourth receiving portion protruding linearly in the same direction as the fourth rib portion and for receiving the over-compression load of the fourth rib portion,

[0038] The direction in which the third receiving portion of the third separator extends linearly and the direction in which the fourth receiving portion of the fourth separator extends linearly are configured to be non-parallel.

[0039]

[10] The stacked structure of fuel cell separators according to [9] above, wherein the direction in which the second receiving portion of the second separator extends linearly and the direction in which the fourth receiving portion of the fourth separator extends linearly are configured to be parallel.

[0040]

[11] The stacked structure of fuel cell separators according to [1] to

[10] above, wherein the two linearly extending directions of the opposing receiving portions are configured to form an angle of 5 to 90°.

[0041]

[12] The stacked structure of fuel cell separators according to [1] to

[10] above, wherein in the one separator of the first group and / or the other separator of the second group, the protruding height of the receiving portion is smaller than the protruding height of the rib portion.

[0042] Advantages of the Invention

[0043] The above-described stacked structure of fuel cell separators can prevent over-compression of the rib portion. In particular, even if the stacked separators are offset in setting, the tops of the opposing receiving portions overlap each other, thereby suppressing a decrease in the reaction force of the receiving portion. As a result, a stable reaction force can be ensured by the opposing receiving portions, over-compression of the rib portion can be suppressed, and deterioration of the rib portion can be effectively suppressed. As described above, the stacked structure of fuel cell separators effectively suppresses performance degradation caused by external influences such as setting offset of the separators and has excellent robustness. Description of the Drawings

[0044] Figure 1 is a top view schematically showing a first group of an embodiment of the stacked structure of fuel cell separators.

[0045] Figure 2 is showing Figure 1 the structure of the AA cross-section of.

[0046] Figure 3 is a top view schematically showing a second group of an embodiment of the stacked structure of fuel cell separators.

[0047] Figure 4 is a sectional perspective view showing the structure of the BB section Figure 3 .

[0048] Figure 5 is a partial cross-sectional view schematically showing a part of a cross-section taken along the stacking direction of unit cells of a fuel cell stack including a unit cell of one embodiment having a fuel cell separator

[0049] Figure 6 is a perspective view schematically showing one embodiment of a stacked structure of fuel cell separators

[0050] Figure 7 is a sectional perspective view showing the structure of a first group of another embodiment of the stacked structure of fuel cell separators

[0051] Figure 8 is a sectional perspective view showing the structure of a second group of another embodiment of the stacked structure of fuel cell separators

[0052] Figure 9 is a perspective view schematically showing another embodiment of the stacked structure of fuel cell separators

[0053] Figure 10 is an enlarged perspective view for explaining an example of a receiving portion in the separator

[0054] Figure 11 is for explaining by Figure 10 the generation state of the reaction force received by the shown receiving portion

[0055] Figure 12 is an enlarged perspective view for explaining another example of a receiving portion in the separator

[0056] Figure 13 is for explaining by Figure 12 the generation state of the reaction force received by the shown receiving portion

[0057] Figure 14 is an enlarged perspective view for explaining yet another example of a receiving portion in the separator

[0058] Figure 15 is an enlarged perspective view for explaining yet another example of a receiving portion in the separator

[0059] Figure 16 is an enlarged perspective view for explaining yet another example of a receiving portion in the separator

[0060] Figure 17 is an enlarged perspective view for explaining yet another example of a receiving portion in the separator

[0061] Figure 18 It is a perspective view schematically showing the structure of a fuel cell stack. Detailed Embodiment

[0062] Hereinafter, embodiments of the present invention will be described with reference to the drawings. It should be noted that the present invention is not limited to the following embodiments, and it should be understood that within the scope not departing from the gist of the present invention, based on the common knowledge of those skilled in the art, appropriate design changes, improvements, etc. can be added.

[0063] One embodiment of the laminated structure of the fuel cell separator includes as Figure 1 and Figure 2 shown, a first group 11 as Figure 3 and Figure 4 shown, and a laminated structure 100 of fuel cell separators of a second group 21 as

[0064] In the laminated structure 100 of fuel cell separators, one separator 12 and the other separator 22 are relatively arranged in such a manner that the surfaces on the side where the rib portions 14, 24 and the receiving portions 16, 26 project face each other. And, the direction in which the receiving portion 16 of one separator 12 extends linearly and the direction in which the receiving portion 26 of the other separator 22 extends linearly are configured to be non-parallel, and a part of the opposing receiving portions 16, 26 overlaps each other.

[0065] More specifically, as Figure 5 and Figure 6 shown, in the laminated structure 100 of fuel cell separators, the first group 11 and the second group 21 are laminated in such a manner that the second outer surface 12Q side of the second separator 12b constituting the first group 11 faces the third outer surface 22P side of the third separator 22a constituting the second group 21. The first group 11 and the second group 21 are metal plate-like parts constituting unit cells 10, 20 in a fuel cell stack. Regarding the fuel cell stack, after laminating a plurality of unit cells 10, 20, in order to prevent these unit cells 10, 20 from shifting and to be in a state of being fastened by applying an external force in the lamination direction. For example, the laminated structure 100 of fuel cell separators can be used as a fuel cell stack 300 including the laminated structure 100 of fuel cell separators in which a plurality of unit cells 10 are laminated as Figure 18 shown.Figure 18 is a perspective view schematically showing the structure of the fuel cell stack 300.

[0066] Here, Figure 1 is a top view of a first group showing one embodiment of the laminated structure of fuel cell separators, Figure 2 shows Figure 1 the structure of the AA cross-section in a sectional perspective view. Figure 3 is a top view of a second group showing one embodiment of the laminated structure of fuel cell separators. Figure 4 shows Figure 3 the structure of the BB cross-section in a sectional perspective view. Figure 5 is a partial cross-sectional view schematically showing a part of a cross-section taken along the stacking direction of unit cells of a fuel cell stack including unit cells having one embodiment of fuel cell separators. Figure 6 is a perspective view schematically showing one embodiment of the laminated structure of fuel cell separators.

[0067] It should be noted that the unit cells 10 and 20 are, for example, metal components constituting a polymer electrolyte fuel cell or the like. The unit cells 10 and 20, for example, in addition to a pair of first group 11 and second group 21 constituting the laminated structure 100 of fuel cell separators, also have a membrane electrode assembly 51 sandwiched between the first group 11 and the second group 21, a gas flow path 50 provided between the membrane electrode assembly 51 and the first group 11 and the second group 21, and the like. The membrane electrode assembly 51, for example, has an electrolyte membrane 52 made of a polymer electrolyte membrane or the like, a pair of electrolyte catalyst layers 53 sandwiching the electrolyte membrane 52, and a gas diffusion layer 58 disposed to cover the electrolyte catalyst layers 53. The unit cells 10 and 20 of the fuel cell, for example, are components that generate electricity through a chemical reaction between hydrogen (fuel gas) supplied from the anode side and oxygen (oxidant gas) supplied from the cathode side.

[0068] The first group 11 is, for example, composed of two separators 12 laminated in the plate thickness direction. Hereinafter, one separator 12 constituting the first group 11 is designated as the first separator 12a, and the other separator 12 is designated as the second separator 12b. In addition, the surface where the laminated first separator 12a and second separator 12b are in contact with each other is designated as the first contact surface 12O. And the surface of the first separator 12a on the side opposite to the first contact surface 12O is designated as the first outer surface 12P, and the surface of the second separator 12b on the side opposite to the first contact surface 12O is designated as the second outer surface 12Q.

[0069] Similarly, the second group 21 is composed of, for example, two partition plates 22 laminated in the plate thickness direction. Hereinafter, one partition plate 22 constituting the second group 21 is defined as the third partition plate 22a, and the other partition plate 22 is defined as the fourth partition plate 22b. In addition, the surface where the laminated third partition plate 22a and fourth partition plate 22b are in contact with each other is defined as the second contact surface 22O. Further, the surface of the third partition plate 22a on the side opposite to the second contact surface 22O is defined as the third outer surface 22P, and the surface of the fourth partition plate 22b on the side opposite to the second contact surface 22O is defined as the fourth outer surface 22Q.

[0070] The first partition plate 12a has: a first rib portion 14a that protrudes toward the first outer surface 12P side; and a first receiving portion 16a that protrudes linearly in the same direction as the first rib portion 14a and is used to receive the over-compression load of the first rib portion 14a.

[0071] The second partition plate 12b has: a second rib portion 14b that protrudes toward the second outer surface 12Q side; and a second receiving portion 16b that protrudes linearly in the same direction as the second rib portion 14b and is used to receive the over-compression load of the second rib portion 14b.

[0072] The third partition plate 22a has: a third rib portion 24a that protrudes toward the third outer surface 22P side; and a third receiving portion 26a that protrudes linearly in the same direction as the third rib portion 24a and is used to receive the over-compression load of the third rib portion 24a.

[0073] The fourth partition plate 22b has: a fourth rib portion 24b that protrudes toward the fourth outer surface 22Q side; and a fourth receiving portion 26b that protrudes linearly in the same direction as the fourth rib portion 24b and is used to receive the over-compression load of the fourth rib portion 24b.

[0074] Hereinafter, the first rib portion 14a, the second rib portion 14b, the third rib portion 24a, and the fourth rib portion 24b are sometimes collectively referred to simply as "rib portions 14, 24". Similarly, the first receiving portion 16a, the second receiving portion 16b, the third receiving portion 26a, and the fourth receiving portion 26b are sometimes collectively referred to simply as "receiving portions 16, 26".

[0075] The rib portions 14, 24 are convex portions where the first group 11 and the second group 21 of adjacent unit cells 10, 20 are joined, and there is no particular limitation on the shape on the plane of the laminated structure 100 of the fuel cell separator plates. For example, a rib portion that forms a ring on the plane of the laminated structure 100 of the fuel cell separator plates can be cited (for example, refer to Figure 1 and Figure 3), but it may not be circular. For example, the shapes of the rib portions 14 and 24 on the plane of the stacked structure 100 of the fuel cell separator may also be mirror-image shapes in adjacent unit cells 10 and 20 (i.e., the first group 11 and the second group 21). For example, if the rib portion 14 of the first group 11 and the rib portion 24 of the second group 21 are mirror-image shapes, then the rib portions 14 and 24 of both sides are in contact with each other in the stacked structure 100 of the fuel cell separator. A seal 54 may be provided at the vertex portions of the rib portions 14 and 24 and arranged to be in contact with the adjacent unit cells 10 and 20.

[0076] In the stacked structure 100 of the fuel cell separator, the receiving portions 16 and 26 for receiving the over-compression load of the rib portions 14 and 24 have a particularly important structure. That is, in the stacked structure 100 of the fuel cell separator, the direction in which the second receiving portion 16b of the second separator 12b extends linearly and the direction in which the third receiving portion 26a of the third separator 22a extends linearly are configured to be non-parallel, and a part of the second receiving portion 16b and the third receiving portion 26a are relatively arranged in an overlapping manner. By configuring in this way, it is possible to extremely effectively prevent the over-compression of the rib portions 14 and 24. That is, even when there is a setting deviation between the first group 11 and the second group 21, the contact of the high reaction force portion can be well maintained by the overlapping of the tops of the relative second receiving portion 16b and the third receiving portion 26a, and the decrease in the reaction forces of the second receiving portion 16b and the third receiving portion 26a can be suppressed. Thereby, a stable reaction force can be ensured by the second receiving portion 16b and the third receiving portion 26a, the over-compression of the rib portions 14 and 24 can be suppressed, and the deterioration of the rib portions 14 and 24 can be effectively suppressed. Therefore, the stacked structure 100 of the fuel cell separator effectively suppresses the performance degradation caused by external influences such as setting deviation and has excellent robustness.

[0077] The second receiving portion 16b and the third receiving portion 26a are linear protruding portions for receiving the over-compression load of the rib portions 14 and 24. As described above, as long as the linearly extending directions of each other are non-parallel, the shape on the plane of the stacked structure 100 of the fuel cell separator is not particularly limited. For example, the second receiving portion 16b and the third receiving portion 26a are preferably configured to be linear with both ends on the plane of the stacked structure 100 of the fuel cell separator and arranged to have a non-parallel positional relationship in a manner that a part of each other intersects. In addition, there is no particular limitation on the cross-sectional shape orthogonal to the linearly extending direction of the second receiving portion 16b and the third receiving portion 26a. Hereinafter, the cross-sectional shape orthogonal to the linearly extending direction of the receiving portions 16 and 26 will sometimes be simply referred to as the "cross-sectional shape" of the receiving portions 16 and 26. The specific cross-sectional shape and the shape of the uppermost surface of each receiving portion 16 and 26 will be described later.

[0078] As long as the stacked structure 100 of the fuel cell separator plates is arranged such that the receiving portions 16 and 26 protruding toward the opposing surfaces (the second outer surface 12Q and the third outer surface 22P) of the first group 11 and the second group 21 to be stacked have a non-parallel positional relationship, there are no particular restrictions on the other receiving portions 16 and 26. Here, the stacked structure 100 of the fuel cell separator plates may further include other groups (not shown) of other separator plates on the first outer surface 12P side of the first group 11 and the fourth outer surface 22Q side of the second group 21. For these other groups, it is preferable that the opposing receiving portions 16 and 26 are configured to have a non-parallel positional relationship.

[0079] In Figure 2 and Figure 6 shown in the first group 11, the direction in which the first receiving portion 16a of the first separator plate 12a extends linearly and the direction in which the second receiving portion 16b of the second separator plate 12b extends linearly are configured to be parallel. For example, the first receiving portion 16a and the second receiving portion 16b of the first group 11 configured in this way may also be formed to be mirror-symmetrical with respect to the first abutting surface 12O.

[0080] In addition, in Figure 4 and Figure 6 shown in the second group 21, the direction in which the third receiving portion 26a of the third separator plate 22a extends linearly and the direction in which the fourth receiving portion 26b of the fourth separator plate 22b extends linearly are configured to be parallel. For example, the third receiving portion 26a and the fourth receiving portion 26b of the second group 21 configured in this way may also be formed to be mirror-symmetrical with respect to the second abutting surface 22O.

[0081] In the stacked structure 100 of the fuel cell separator plates including the first group 11 and the second group 21 as shown in Figure 6 , the stability during the stacking of the first group 11 and the second group 21 is extremely excellent, and stable sealing based on the rib portions 14 and 24 can be achieved.

[0082] In addition, the stacked structure of the fuel cell separator plates may also be the stacked structure 200 of the fuel cell separator plates configured as shown in Figures 7 - 9 . Here, Figure 7 is a cross-sectional perspective view showing the structure of the first group in another embodiment of the stacked structure of the fuel cell separator plates. Figure 8 is a cross-sectional perspective view showing the structure of the second group in another embodiment of the stacked structure of the fuel cell separator plates. Figure 9 is a perspective view schematically showing another embodiment of the stacked structure of the fuel cell separator plates.

[0083] Figure 9The stacked structure 200 of the fuel cell separator shown includes Figure 7 a first group 31 as shown and Figure 8 a second group 41 as shown. Similar to the stacked structure 100 of the fuel cell separator described so far (for example, refer to Figure 6 ), the first group 31 has a first separator 32a and a second separator 32b stacked in the plate thickness direction. In addition, the second group 41 has a third separator 42a and a fourth separator 42b stacked in the plate thickness direction.

[0084] The first separator 32a has a first rib portion 34a protruding toward the first outer surface 32P side and a first receiving portion 36a protruding linearly in the same direction as the first rib portion 34a. In addition, the second separator 32b has a second rib portion 34b protruding toward the second outer surface 32Q side and a second receiving portion 36b protruding linearly in the same direction as the second rib portion 34b.

[0085] The third separator 42a has a third rib portion 44a protruding toward the third outer surface 42P side and a third receiving portion 46a protruding linearly in the same direction as the third rib portion 44a. The fourth separator 42b has a fourth rib portion 44b protruding toward the fourth outer surface 42Q side and a fourth receiving portion 46b protruding linearly in the same direction as the fourth rib portion 44b.

[0086] Regarding the stacked structure 200 of this fuel cell separator, the direction in which the second receiving portion 36b of the second separator 32b extends linearly and the direction in which the third receiving portion 46a of the third separator 42a extends linearly are also configured to be non-parallel, and a part of the second receiving portion 36b and the third receiving portion 46a are relatively arranged in an overlapping manner. Among them, for the stacked structure 200 of this fuel cell separator, the shapes of the first receiving portion 36a of the first separator 32a constituting the first group 31 and the fourth receiving portion 46b of the fourth separator 42b constituting the second group 41 are different from Figure 6 the stacked structure 100 of the fuel cell separator shown.

[0087] Specifically, regarding Figure 7 and Figure 9 the first group 31 shown, the direction in which the first receiving portion 36a of the first separator 32a extends linearly and the direction in which the second receiving portion 36b of the second separator 32b extends linearly are configured to be non-parallel.

[0088] In addition, regarding Figure 8 and Figure 9 the second group 41 shown, the direction in which the third receiving portion 46a of the third separator 42a extends linearly and the direction in which the fourth receiving portion 46b of the fourth separator 42b extends linearly are configured to be non-parallel.

[0089] On the other hand, regarding the laminated structure 200 of the fuel cell separator plates of the present invention, the direction in which the first receiving portion 36a of the first separator plate 32a constituting the first group 31 extends linearly is parallel to the direction in which the third receiving portion 46a of the third separator plate 42a constituting the second group 41 extends linearly.

[0090] In addition, regarding the laminated structure 200 of the fuel cell separator plates of the present invention, the direction in which the second receiving portion 36b of the second separator plate 32b constituting the first group 31 extends linearly is parallel to the direction in which the fourth receiving portion 46b of the fourth separator plate 42b constituting the second group 41 extends linearly.

[0091] In the laminated structure 200 of the fuel cell separator plates of the present invention, the shapes of the first group 31 and the second group 41 are substantially the same. That is, regarding the laminated structure 200 of the fuel cell separator plates of the present invention, a pair of separator plates 32 and 42 of the first group 31 and the second group 41 that become the unit cells 20 and 40 are formed into a non-mirror-symmetric structure with respect to their respective abutting surfaces (the first abutting surface 32O and the second abutting surface 42O). By configuring in this way, by substantially laminating one type of separator plate, the directions in which the respective linearly extending receiving portions 36 and 46 face each other can be made non-parallel, and a decrease in performance caused by the setting offset can be effectively suppressed.

[0092] Of course, regarding the shapes and the directions in which the first receiving portion 36a of the first separator plate 32a and the fourth receiving portion 46b of the fourth separator plate 42b extend linearly, they are not limited to the cases described so far. As described above, they can be appropriately changed according to various cases such as the case where other groups having other separator plates are further provided.

[0093] Return to Figures 1 - 6 , and continue with the description of the laminated structure 100 of the fuel cell separator plates.

[0094] The separator plates 12 and 22 constituting the first group 11 and the second group 21 are plate-shaped members made of metal. Regarding their materials, there is no particular limitation as long as they are metals, and the same materials as those of the conventionally known metal separator plates can be used. For example, as the materials of the separator plates 12 and 22, stainless steel, titanium, etc. can be cited.

[0095] The first separator plate 12a and the second separator plate 12b constituting the first group 11 can either be joined to each other or simply overlapped and laminated. Similarly, the third separator plate 22a and the fourth separator plate 22b constituting the second group 21 can either be joined to each other or simply overlapped and laminated.

[0096] Communication holes 18 are provided in the first group 11 and the second group 21. The communication holes 18 communicate with each other in the stacking direction and are used for supplying / exhausting oxidant gas and fuel gas. For example, the communication holes 18 are preferably provided at the edge portions of either the first group 11 or the second group 21.

[0097] The rib portions 14 and 24 protrude toward the electrolyte membrane 52, for example, and are formed in a seamless state over the entire outer periphery of the stacked structure 100 of the fuel cell separators. In addition, when the communication holes 18 are provided, they may also be formed to surround the communication holes 18.

[0098] The receiving portions 16 and 26 are linear protrusions that protrude in the same direction as the rib portions 14 and 24 of their respective separators 12 and 22. For example, they are preferably provided around their respective rib portions 14 and 24. For example, the receiving portions 16 and 26 are preferably provided within a specified range near the rib lines of the rib portions 14 and 24 of their respective separators 12 and 22. For example, the actual distance from the lower edge of the rib line of the rib portion 14 and 24 to the lower edge of the adjacent receiving portion 16 and 26 is, for example, 1 mm or more. The distance between the rib line of the rib portion 14 and 24 and the receiving portion 16 and 26 is defined as the distance between the lower edges of their respective protrusions. The receiving portions 16 and 26 are preferably provided within a range of 1 to 30 mm from their respective rib portions 14 and 24 of the separators 12 and 22. By being configured in this way, when an over-compression load is generated in the adjacent rib portions 14 and 24, the over-compression load can be effectively received.

[0099] The protruding height of the receiving portions 16 and 26 is preferably smaller than the protruding height of the rib portions 14 and 24 of their respective separators 12 and 22. For example, it is preferred that the protruding height of the second receiving portion 16b toward the second outer surface 12Q side is smaller than the protruding height of the second rib portion 14b toward the second outer surface 12Q side, and the protruding height of the third receiving portion 26a toward the third outer surface 22P side is smaller than the protruding height of the third rib portion 24a toward the third outer surface 22P side. It should be noted that the protruding height of the first receiving portion 16a toward the first outer surface 12P side may also be smaller than the protruding height of the first rib portion 14a toward the first outer surface 12P side. Further, the protruding height of the fourth receiving portion 26b toward the fourth outer surface 22Q side may also be smaller than the protruding height of the fourth rib portion 24b toward the fourth outer surface 22Q side.

[0100] The receiving portions 16 and 26 with respect to the rib lines of the rib portions 14 and 24 can be either a single linear protrusion or a plurality of linear protrusions. For example, in the laminated structure 100 of the fuel cell separator of the present invention, an example is shown in which three linear receiving portions 16 and 26 are respectively provided with respect to the rib lines of the rib portions 14 and 24. The receiving portions 16 and 26 can be provided either inside or outside the rib lines of the rib portions 14 and 24. In addition, they can also be provided at both the inside and the outside of the rib lines of the rib portions 14 and 24.

[0101] In the laminated structure 100 of the fuel cell separator, the opposing receiving portions 16 and 26 being configured to be non-parallel to each other means that the direction of linear extension of one receiving portion 16 is not parallel to the direction of linear extension of the other receiving portion 26, and the opposing receiving portions 16 and 26 are relatively arranged in such a way that a part of each other overlaps. That is, in the receiving portions 16 and 26 configured to be non-parallel, the non-overlapping portions of any one of the receiving portions 16 and 26 become the adjustment amount for allowing the offset during lamination. For example, regarding the direction of linear extension of the opposing receiving portions 16 and 26, the direction of linear extension of the other is preferably inclined at an angle of 5 to 90° with respect to the direction of linear extension of one, and more preferably inclined at an angle of 10 to 90°. In particular, when the inclination angle of the direction of linear extension of the above-mentioned opposing receiving portions 16 and 26 is set to 10 to 90°, the length of the receiving portions 16 and 26 can be further shortened, and by setting the range of the receiving portions 16 and 26 to be smaller, it contributes to the miniaturization of the laminated structure 100 of the fuel cell separator. Among them, in the opposing receiving portions 16 and 26 configured to be non-parallel, if the adjustment amount for allowing the offset during setting can be sufficiently ensured, the inclination angle (that is, the angle of intersection of the directions of linear extension) can also be smaller than the above-mentioned angle range. It should be noted that as the main factors for the setting offset between the separators in the laminated structure 100 of the fuel cell separator, for example, fluctuations in the dimensions of the separators and composite factors of misalignment during bonding can be cited.

[0102] In addition, when each of the receiving portions 16 and 26 is provided close to the rib portions 14 and 24 of their respective separators 12 and 22, it is preferable that the direction of linear extension of each of the receiving portions 16 and 26 is parallel or inclined at an angle of 45° or less with respect to the extension direction of the rib lines of the rib portions 14 and 24.

[0103] There is no particular limitation on the cross-sectional shape and the shape of the uppermost surface of the receiving portions 16 and 26, as long as they can withstand the over-compression load of the rib portions 14 and 24. For example, the receiving portions 16 and 26 can be, for example, as Figure 10As shown by the receiving part 16 (second receiving part 16b), the shape of the uppermost surface 16X is curved. The center side of the uppermost surface 16X of the receiving part 16 with such a shape becomes the high reaction force part 19. And, along Figure 10 the direction indicated by the arrow of Figure 10 a reaction force is generated. In Figure 11 an example of the relative arrangement of the receiving parts 16 and 26 with the shape of the uppermost surface 16X being curved as described above is shown. By arranging the receiving parts 16 and 26 relative to each other as Figure 11 such, even when there is a setting deviation during the lamination of each group having its own partition (also simply referred to as "when the partitions are laminated"), the high reaction force parts 19 of each other come into good contact with each other, and over-compression of the rib part (not shown) can be effectively prevented. Here, Figure 10 is an enlarged perspective view for explaining an example of the receiving part in the partition, Figure 11 and Figure 10 is a perspective view for explaining the generation state of the reaction force received by the receiving part shown by

[0104] In addition, for example, Figure 12 as shown by the receiving part 16 (second receiving part 16b), the shape of the uppermost surface 16X may also be flat. The two end sides of the uppermost surface 16X of the receiving part 16 with such a shape become the high reaction force parts 19. And, along Figure 12 the direction indicated by the arrow of Figure 12 a reaction force is generated. In Figure 13 an example of the relative arrangement of the receiving parts 16 and 26 with the shape of the uppermost surface 16X being flat as described above is shown. By arranging the receiving parts 16 and 26 relative to each other as Figure 13 such, even when there is a setting deviation during the lamination of the partitions, the high reaction force parts 19 of each other come into good contact with each other, and over-compression of the rib part (not shown) can be effectively prevented. Here, Figure 12 is an enlarged perspective view for explaining another example of the receiving part in the partition, Figure 13 and Figure 12 is a perspective view for explaining the generation state of the reaction force received by the receiving part shown by

[0105] In addition, each of the receiving parts 16 and 26 may also be, for example, Figures 14 - 17 the shape as shown by Figure 14 For example, the receiving part 56 shown by Figure 15 has a cross-sectional shape that protrudes in two stages. That is, the receiving part 56 has a second protrusion part 57 on the protruding uppermost surface side. The receiving part 66 shown by Figure 15 has a groove part 67 that is recessed inward on the uppermost surface side.Figure 16 The receiving part 76 shown has a side groove part 77 recessed inward on the inclined surface part protruding toward the uppermost surface side. Figure 17 The receiving part 86 shown has a pit part 87 (dented part) recessed inward on the uppermost surface side. In this way, each of the receiving parts 16 and 26 is not just a simple protrusion protruding in one direction, but can appropriately be provided with recessed groove parts, pit parts, etc. with respect to the uppermost surface and the inclined surface part of the side surface that form the protrusion.

[0106] There is no particular limitation on the method for manufacturing the laminated structure of the fuel cell separator. For example, a method of stamping a flat plate made of metal to form rib parts and receiving parts can be cited.

[0107] Industrial applicability

[0108] The laminated structure of the fuel cell separator of the present invention can be used as a fuel cell separator used in an in-vehicle fuel cell stack used in a vehicle or the like.

[0109] Explanation of reference numerals

[0110] 10, 30: Unit cell

[0111] 11, 31: First group

[0112] 12, 32: Separator

[0113] 12a, 32a: First separator

[0114] 12b, 32b: Second separator

[0115] 12O, 32O: First abutting surface

[0116] 12P, 32P: First outer surface

[0117] 12Q, 32Q: Second outer surface

[0118] 14, 34: Rib part

[0119] 14a, 34a: First rib part

[0120] 14b, 34b: Second rib part

[0121] 16, 36: Receiving part

[0122] 16a, 36a: First receiving part

[0123] 16b, 36b: Second receiving part

[0124] 16X: Uppermost surface (uppermost surface of the receiving part)

[0125] 18: Communication hole

[0126] 19: High reaction force part

[0127] 20, 40: Unit cell

[0128] 21, 41: Second group

[0129] 22, 42: Separator

[0130] 22a, 42a: Third separator

[0131] 22b, 42b: Fourth separator

[0132] 22O, 42O: Second abutting surface

[0133] 22P, 42P: Third outer surface

[0134] 22Q, 42Q: Fourth outer surface

[0135] 24, 44: Rib part

[0136] 24a, 44a: Third rib part

[0137] 24b, 44b: Fourth rib part

[0138] 16, 36: Bearing part

[0139] 26a, 46a: Third bearing part

[0140] 26b, 46b: Fourth bearing part

[0141] 50: Gas flow path

[0142] 51: Membrane electrode assembly

[0143] 52: Electrolyte membrane

[0144] 53: Electrolyte catalyst layer

[0145] 54: Sealant

[0146] 56, 66, 76, 86: Bearing part

[0147] 57: Second protrusion part

[0148] 58: Gas diffusion layer

[0149] 67: Groove part

[0150] 77: Side groove part

[0151] 87: Dimple part (indentation part)

[0152] 100: Stacked structure of fuel cell separators

[0153] 200: Stacked structure of fuel cell separators

[0154] 300: Fuel cell stack

Claims

1. A stacked structure of fuel cell separators, in which two or more fuel cell separators constituting unit cells of a fuel cell stack are stacked, wherein, the stacked structure of the fuel cell separators includes: a first group having one separator; and a second group having another separator, the one separator and the another separator each have: a rib portion protruding toward one surface side; and a receiving portion protruding linearly in the same direction as the rib portion and for receiving an over-compression load of the rib portion, the one separator and the another separator are disposed opposite to each other with the surfaces on the side where the rib portion and the receiving portion protrude facing each other, the direction in which the receiving portion of the one separator extends linearly and the direction in which the receiving portion of the another separator extends linearly are configured to be non-parallel, and a part of the opposing receiving portions overlap each other.

2. The stacked structure of the fuel cell separator according to claim 1, wherein, Including: the first group constituted by a first separator and a second separator stacked in the plate thickness direction; and the second group constituted by a third separator and a fourth separator stacked in the plate thickness direction, the second separator has: a second rib portion protruding toward a second outer surface side opposite to a first abutting surface that abuts against the stacked first separator and second separator; and a second receiving portion protruding linearly in the same direction as the second rib portion and for receiving an over-compression load of the second rib portion, the third separator has: a third rib portion protruding toward a third outer surface side opposite to a second abutting surface that abuts against the stacked third separator and fourth separator; and a third receiving portion protruding linearly in the same direction as the third rib portion and for receiving an over-compression load of the third rib portion, the first group and the second group are stacked in such a manner that the second outer surface side of the second separator constituting the first group faces the third outer surface of the third separator constituting the second group, the direction in which the second receiving portion of the second separator extends linearly and the direction in which the third receiving portion of the third separator extends linearly are configured to be non-parallel, and they are disposed opposite to each other in such a manner that a part of the second receiving portion and the third receiving portion overlap each other.

3. The stacked structure of fuel cell separators according to claim 2, wherein, the first separator has: a first rib portion protruding toward a first outer surface side opposite to the first abutting surface; and a first receiving portion protruding linearly in the same direction as the first rib portion and for receiving an over-compression load of the first rib portion, the direction in which the first receiving portion of the first separator extends linearly and the direction in which the second receiving portion of the second separator extends linearly are configured to be parallel.

4. The stacked structure of fuel cell separators according to claim 3, wherein, the first receiving portion and the second receiving portion are formed to be mirror-symmetrical with respect to the first abutting surface.

5. The stacked structure of fuel cell separators according to claim 2, wherein, The fourth partition plate has: a fourth rib portion that protrudes toward the fourth outer surface side opposite to the second abutting surface; and a fourth bearing portion that protrudes linearly in the same direction as the fourth rib portion and is used to receive the over-compression load of the fourth rib portion. The direction in which the third bearing portion of the third partition plate extends linearly is parallel to the direction in which the fourth bearing portion of the fourth partition plate extends linearly.

6. The laminated structure of fuel cell partition plates according to claim 5, wherein The third bearing portion and the fourth bearing portion are mirror-symmetric with respect to the second abutting surface.

7. The laminated structure of fuel cell partition plates according to claim 2, wherein The first partition plate has: a first rib portion that protrudes toward the first outer surface side opposite to the first abutting surface; and a first bearing portion that protrudes linearly in the same direction as the first rib portion and is used to receive the over-compression load of the first rib portion. The direction in which the first bearing portion of the first partition plate extends linearly is non-parallel to the direction in which the second bearing portion of the second partition plate extends linearly.

8. The laminated structure of fuel cell partition plates according to claim 7, wherein The direction in which the first bearing portion of the first partition plate extends linearly is parallel to the direction in which the third bearing portion of the third partition plate extends linearly.

9. The laminated structure of fuel cell partition plates according to claim 2, wherein The fourth partition plate has: a fourth rib portion that protrudes toward the fourth outer surface side opposite to the second abutting surface; and a fourth bearing portion that protrudes linearly in the same direction as the fourth rib portion and is used to receive the over-compression load of the fourth rib portion. The direction in which the third bearing portion of the third partition plate extends linearly is non-parallel to the direction in which the fourth bearing portion of the fourth partition plate extends linearly.

10. The laminated structure of fuel cell partition plates according to claim 9, wherein The direction in which the second bearing portion of the second partition plate extends linearly is parallel to the direction in which the fourth bearing portion of the fourth partition plate extends linearly.

11. The laminated structure of fuel cell partition plates according to any one of claims 1 to 10, wherein The two linearly extending directions of the opposing bearing portions form an angle of 5 to 90°.

12. The laminated structure of fuel cell partition plates according to any one of claims 1 to 10, wherein In one partition plate of the first group and / or the other partition plate of the second group, the protruding height of the bearing portion is smaller than the protruding height of the rib portion.

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