Fuel Cell Unit

Abstract

To provide a fuel cell unit which is easy to install.SOLUTION: In a fuel cell unit, an electric power converter (20) placed on a first face of a fuel cell stack (10), and an auxiliary unit (30) is connected to a second face of the fuel cell stack (10) via a stack manifold. The normal direction of the first face crosses the normal direction of the second face. A fuel cell unit (100) has at least a first auxiliary unit (30A) as the auxiliary unit (30). In a plan view of the fuel cell unit (100) from the auxiliary unit side, defining an area surrounded by the outer edge of the first auxiliary unit (30A) as an area A; an area surrounded by the outer edge of the fuel cell stack (10) as an area B1; an area surrounded by the outer edge of the electric power converter (20) as an area B2; an area where the area B1 and the area B2 are added as an area B3, the area A overlaps with at least a portion of the area B1 and at least a portion of the area B2, and all of the area A is included inside the area B3.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to a fuel cell unit. [Background technology]

[0002] A fuel cell is a battery that generates electrical energy through a chemical reaction between an oxidant gas containing oxygen and a fuel gas containing hydrogen. The basic unit of a fuel cell (fuel cell stack), a cell (single cell), generally comprises a membrane electrode assembly (MEA) in which electrode catalyst layers are formed on both sides of a solid polymer electrolyte membrane, a gas diffusion layer (GDL) on the outside of the MEA, and a separator with a gas flow path on the outside of the GDL.

[0003] A fuel cell unit is composed of at least a fuel cell stack and a power converter. A fuel cell unit is usually equipped with auxiliary devices that assist the operation of the fuel cell. For example, Patent Document 1 discloses a fuel cell unit in which a converter, whose reactors are arranged approximately parallel to the stacking direction of the unit cells, is disposed above or below the fuel cell stack. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2017-135093 A Summary of the Invention [Problem to be solved by the invention]

[0005] When a fuel cell unit is mounted on, for example, a fuel cell vehicle (FCEV), it is preferable that the fuel cell unit be easily mountable (easy to install). The present disclosure has been made in view of the above-mentioned circumstances, and has as its main object to provide a fuel cell unit that is easily mountable. [Means for solving the problem]

[0006] [1] A fuel cell unit comprising a fuel cell stack, a power converter that converts the power of the fuel cell stack, and auxiliary equipment that assists in the operation of the fuel cell stack, wherein the power converter is arranged on a first side of the fuel cell stack, and the auxiliary equipment is connected to a second side of the fuel cell stack via a stack manifold, and a normal direction of the first side and a normal direction of the second side intersect, the fuel cell unit has at least a first auxiliary equipment as the auxiliary equipment, and when, in a planar view of the fuel cell unit from the auxiliary equipment side, an area surrounded by the outer edge of the first auxiliary equipment is defined as area A, an area surrounded by the outer edge of the fuel cell stack is defined as area B1, an area surrounded by the outer edge of the power converter is defined as area B2, and a combined area of ​​area B1 and area B2 is defined as area B3, area A overlaps with at least a portion of area B1 and at least a portion of area B2, and all of area A is included inside area B3.

[0007] [2] The fuel cell unit has a second auxiliary component as the auxiliary component, and when the area surrounded by the outer edge of the second auxiliary component in the planar view is defined as area C, the entirety of area C is included inside either area B1 or area B2. The fuel cell unit described in [1].

[0008] [3] The fuel cell unit according to [1] or [2], wherein the fuel cell unit does not have any auxiliary components protruding from the region B3.

[0009] [4] The fuel cell unit according to any one of [1] to [3], wherein the first auxiliary device is at least one of a gas-liquid separator, a humidifier, and an ejector.

[0010] [5] The fuel cell unit is a fuel cell unit described in any of [1] to [4], wherein the fuel cell unit has a converter and an inverter as the power converter, and the converter and the inverter are arranged in order from the first surface side. Effect of the Invention

[0011] The present disclosure has an effect of providing a fuel cell unit that is easy to mount. [Brief description of the drawings]

[0012] [Figure 1] 1 is a schematic plan view illustrating a fuel cell unit according to the present disclosure. [Diagram 2] 5 is a schematic plan view illustrating the effect of the fuel cell unit according to the present disclosure. FIG. [Diagram 3] 1 is a schematic plan view illustrating a fuel cell unit according to the present disclosure. [Figure 4] 1 is a schematic plan view illustrating a fuel cell unit according to the present disclosure. [Diagram 5] 1 is a schematic plan view illustrating a fuel cell unit according to the present disclosure. [Figure 6] 1 is a schematic cross-sectional view illustrating a fuel cell stack and a single cell according to the present disclosure. [Figure 7] 1 is a schematic plan view illustrating a fuel cell unit according to the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] The fuel cell unit in the present disclosure will be described in detail below. Each of the figures shown below is a schematic illustration, and the size and shape of each part are appropriately exaggerated to facilitate understanding. In addition, in this specification, when expressing an aspect in which another member is arranged relative to a certain member, the term "above" or "below" is used, unless otherwise specified, it includes both a case in which another member is arranged directly above or below a certain member so as to be in contact with the certain member, and a case in which another member is arranged above or below a certain member via another member.

[0014] FIG. 1 is a schematic plan view illustrating a fuel cell unit in the present disclosure. FIG. 1(a) is a plan view of the fuel cell unit viewed from the auxiliary side, and FIG. 1(b) is a plan view of FIG. 1(a) viewed from the left and right direction of the paper. As shown in FIGS. 1(a) and 1(b), the fuel cell unit 100 has a fuel cell stack 10, a power converter 20 that converts the power of the fuel cell stack 10, and an auxiliary 30 that assists the operation of the fuel cell stack 10. Also, as shown in FIGS. 1(a) and 1(b), the power converter 20 is disposed on a first surface X of the fuel cell stack 10, and the auxiliary 30 is connected to a second surface Y of the fuel cell stack 10 via a stack manifold (not shown). Also, as shown in FIG. 1(b), a normal direction M of the first surface X and a normal direction N of the second surface Y intersect. And, the fuel cell unit 100 has a first auxiliary 30A as the auxiliary 30. Furthermore, as shown in Figure 1(a), in a plan view of the fuel cell unit 100 seen from the auxiliary device 30 side, if the area surrounded by the outer edge of the first auxiliary device 30A is defined as area A, the area surrounded by the outer edge of the fuel cell stack 10 is defined as area B1, the area surrounded by the outer edge of the power converter 20 is defined as area B2, and the combined area of ​​areas B1 and B2 is defined as area B3, area A overlaps with at least a portion of area B1 and at least a portion of area B2, and all of area A is included inside area B3.

[0015] According to the present disclosure, in a plan view of the fuel cell unit from the auxiliary side, area A surrounded by the outer edge of the first auxiliary overlaps with at least a portion of area B1 surrounded by the outer edge of the fuel cell stack and at least a portion of area B2 surrounded by the outer edge of the power converter, and all of area A is included inside area B3 defined by the combination of areas B1 and B2, resulting in a fuel cell unit with good mountability.

[0016] The effect of the fuel cell stack in the present disclosure will be described with reference to FIG. 2. FIG. 2(a) is a plan view corresponding to FIG. 1(a), and FIG. 2(b) is a plan view corresponding to FIG. 1(b). As shown in FIG. 2(a) and (b), if the auxiliary device 30 protrudes from the fuel cell stack 10 and the power converter 20, an extra space for mounting the fuel cell stack is required by the area surrounded by the dotted line in the figure, and the mountability is deteriorated. In contrast, in the fuel cell unit in the present disclosure, as shown in FIG. 1(a), the entire area A surrounded by the outer edge of the first auxiliary device 30A is included inside the area B3, which is the sum of the area B1 surrounded by the outer edge of the fuel cell stack 10 and the area B2 surrounded by the outer edge of the power converter 20. Therefore, the mountability with the fuel cell unit can be improved.

[0017] Here, the fuel cell stack and the power converter are typically housed in a fuel cell case and a power converter case, respectively. Therefore, in this disclosure, the area B1 can be considered as an area surrounded by the outer edge of the fuel cell case. Similarly, the area B2 can be considered as an area surrounded by the outer edge of the power converter case. Also, in this disclosure, the "inside" of an area includes the outer edge of the area.

[0018] As shown in FIGS. 1(a) and 1(b), the power converter 20 in the present disclosure is disposed on a first surface X of the fuel cell stack 10. A normal direction M of the first surface X may be parallel to a stacking direction D of the fuel cells (single cells) described later, or may be perpendicular to the stacking direction D of the single cells. In addition, the first surface of the fuel cell stack is preferably a lower surface of the fuel cell stack in the gravity direction. Here, in the present disclosure, "parallel" includes not only strict parallelism but also a case where the angle between two directions is 10° or less. The angle may be 5° or less. In the present disclosure, "orthogonal" includes not only strict perpendicularity but also a case where the angle between two directions is 80° or more and 100° or less. The angle may be 85° or more and 95° or less.

[0019] As shown in Figs. 1(a) and (b), the auxiliary device 30 in the present disclosure is connected to the second surface Y of the fuel cell stack 10. The normal direction N of the second surface Y may be parallel to the stacking direction D of the fuel cells (single cells) described below, or may be perpendicular to the stacking direction D of the single cells. "Parallel" and "perpendicular" are as described above. Furthermore, the normal direction M of the first surface X and the normal direction N of the second surface Y intersect. The normal direction M and the normal direction N may or may not be perpendicular to each other, with the former being preferred. The "perpendicular" is as described above.

[0020] The fuel cell unit in the present disclosure has a first auxiliary as an auxiliary. In the first auxiliary, the region A overlaps with at least a part of the region B1 and at least a part of the region B2. For example, as shown in FIG. 1(a), the ratio of the portion of the region A that overlaps with the region B1 to the entire region A may be 50% or more. On the other hand, as shown in FIG. 3, the ratio of the portion of the region A that overlaps with the region B2 to the entire region A may be 50% or more. Also, the ratio of the portion of the region B1 that overlaps with the region A to the entire region B1 may be, for example, 5% or more, or 10% or more. On the other hand, the ratio of the portion of the region B1 that overlaps with the region A to the entire region B1 may be 100% or less, 70% or less, or 50% or less. The ratio of the portion of the region B2 that overlaps with the region A to the entire region B2 is the same as the above-mentioned region B1.

[0021] Furthermore, in the first auxiliary device of the present disclosure, the entirety of region A is included inside region B3. The ratio of the portion of region B3 that overlaps with region A to the entirety of region B3 is, for example, 5% or more, or may be 10% or more, or may be 30% or more. Meanwhile, the ratio of the portion of region B3 that overlaps with region A to the entirety of region B3 is, for example, 90% or less, or may be 70% or less, or may be 50% or less.

[0022] Also, as shown in FIG. 1(a), in the plan view, the first auxiliary 30A may extend in a normal direction M of the first surface X of the fuel cell unit 10. On the other hand, as shown in FIG. 4, in the plan view, the first auxiliary 30A may extend in a direction intersecting with the normal direction M of the first surface X of the fuel cell unit 10. The intersection may be orthogonal, or may not be orthogonal. The orthogonal is as described above. Also, in the plan view, the shape of the first auxiliary (planar shape of region A) may be a rectangular shape such as a square or a rectangle, a polygonal shape such as a triangle, a circular shape such as a circle or an ellipse, or a shape that combines a polygonal shape and a circular shape. Note that the "polygonal shape" includes not only a strict polygonal shape, but also a shape in which the parts corresponding to the corners of a polygon are formed into an arc shape.

[0023] FIG. 5 is a schematic plan view illustrating a fuel cell unit according to the present disclosure, in which the fuel cell unit is viewed from the auxiliary device side (not shown). As shown in FIG. 5(a), in the fuel cell unit, the width W1 of the region B1 and the width W2 of the region B2 may be the same. On the other hand, as shown in FIG. 5(b), in the fuel cell unit, the width W1 of the region B1 and the width W2 of the region B2 may be different. "The same" means that W2 / W1, which will be described later, is 0.95 or more and 1.05 or less. When the width W1 and the width W2 are different, the ratio of W2 to W1 (W2 / W1) is, for example, 0.5 or more, may be 0.7 or more, or may be 0.9 or more. On the other hand, W2 / W1 is, for example, 1.2 or less. Here, "width W1" refers to the length of the first surface X of the fuel cell stack 10 when the fuel cell unit 100 is viewed from the auxiliary device side in a plan view as shown in FIGS. 5(a) and 5(b). Moreover, "width W2" refers to the length of a surface Z of the power converter 20 that faces the first surface X of the fuel cell stack 10 when the fuel cell 100 is viewed in plan from the auxiliary device side.

[0024] Also, as shown in Figures 5(a) and (b), the shapes (planar shapes) of region B1 and region B2 may each be a rectangle. A "rectangle" includes not only a strict rectangle, but also a shape in which the parts corresponding to the corners of a rectangle are formed in an arc shape. Also, the planar shape of region B3 may be a rectangle as shown in Figure 5(a), or may be a convex shape as shown in Figure 5(b). A "convex shape" includes not only a strict convex shape, but also a shape in which the parts corresponding to the corners of a convex shape are formed in an arc shape.

[0025] 1. Fuel Cell Stack FIG. 6 is a schematic cross-sectional view illustrating a fuel cell stack and a fuel cell (single cell) according to the present disclosure. As shown in FIG. 6(a), the fuel cell stack according to the present disclosure usually has a stacked structure in which a plurality of single cells 40 are stacked. The number of single cells (the number of stacked cells) is usually 2 or more, and may be 5 or more, or may be 10 or more. As described above, the stacking direction D of the plurality of single cells 40 may be parallel to or perpendicular to the normal direction of the first surface of the fuel cell stack. In addition, the stacking direction D of the plurality of single cells 40 may be parallel to or perpendicular to the normal direction of the second surface of the fuel cell stack. Note that, as shown in FIG. 6(a), it is preferable that the surface of the fuel cell stack in the stacking direction D of the single cells 40 is the second surface Y.

[0026] As shown in Fig. 6(a), the fuel cell stack according to the present disclosure is usually housed in a fuel cell case 50. The fuel cell case usually has an opening for electrically connecting the fuel cell stack to a power converter. The material of the fuel cell case is not particularly limited, and may be any conventionally known material.

[0027] The shape of the fuel cell stack as a whole is preferably a rectangular parallelepiped shape. A "rectangular parallelepiped shape" includes not only a strict rectangular parallelepiped shape, but also a shape that can be approximated to a rectangular parallelepiped shape. The shape of the fuel cell stack can also be regarded as the shape of a fuel cell case.

[0028] As shown in FIG. 6(b), a fuel cell (single cell) 40 has a membrane electrode assembly (MEA) 46 in which a cathode side gas diffusion layer 41, a cathode catalyst layer 42, an electrolyte membrane 43, an anode catalyst layer 44, and an anode side gas diffusion layer 45 are stacked in this order, and two separators 47 that sandwich the MEA 46.

[0029] Examples of the electrolyte membrane include fluorine-based electrolyte membranes such as perfluorosulfonic acid membranes and non-fluorine-based electrolyte membranes. Examples of the non-fluorine-based electrolyte membranes include hydrocarbon-based electrolyte membranes. The thickness of the electrolyte membrane is, for example, 5 μm or more and 100 μm or less.

[0030] The cathode catalyst layer and the anode catalyst layer each include, for example, a catalyst metal that promotes an electrochemical reaction, a base material that supports the catalyst metal, an electrolyte having proton conductivity, and carbon particles having electron conductivity. Examples of the catalyst metal include simple metals such as Pt (platinum) and Ru (ruthenium), and alloys containing Pt. Examples of the electrolyte include fluororesins. Examples of the base material and conductive material include carbon materials such as carbon. The thicknesses of the cathode catalyst layer and the anode catalyst layer are, for example, 5 μm or more and 100 μm or less, respectively.

[0031] The anode side gas diffusion layer and the cathode side gas diffusion layer may be conductive members having gas permeability. Examples of the conductive members include carbon porous bodies such as carbon cloth and carbon paper, and metal porous bodies such as metal mesh and foam metal. The thicknesses of the anode side gas diffusion layer and the cathode side gas diffusion layer are, for example, 5 μm or more and 100 μm or less, respectively.

[0032] The separator may have a gas path on the surface facing the gas diffusion layer (anode side gas diffusion layer and cathode side gas diffusion layer). Examples of the material of the separator include metal materials such as stainless steel and carbon materials such as carbon composite materials. The separator has electronic conductivity and also functions as a collector of generated electricity.

[0033] 2. Power Converter The position of the power converter in the present disclosure is as described above. The power converter in the present disclosure is usually housed in a power converter case. The power converter case usually has an opening for electrically connecting the fuel cell stack and the power converter. The material of the power converter case is not particularly limited, and may be a conventionally known material.

[0034] The power converter is not particularly limited as long as it is a member that converts the power of the fuel cell stack. The power converter may be a converter such as a boost converter, a step-down converter, or a step-up / step-down converter capable of both step-up and step-down, or may be an inverter that converts DC power to AC power. The fuel cell unit may have one of the above devices as the power converter, or may have two or more types. For example, when the fuel cell unit has a converter and an inverter as the power converter, it is preferable that the converter and the inverter are arranged in this order from the first surface side. The electricity generated by the fuel cell stack can be passed to the converter and the inverter without being detouring, and the mountability of the fuel cell unit is improved.

[0035] 3. Auxiliary equipment The auxiliary device in the present disclosure is connected to the fuel cell stack via a stack manifold. The fuel cell unit in the present disclosure has at least a first auxiliary device as the auxiliary device. The positions of the auxiliary device and the first auxiliary device are as described above. The stack manifold is a piping component that supplies, for example, an oxidant gas, a fuel gas, and a cooling water to the fuel cell stack. The shape and material of the stack manifold are not particularly limited and can be adjusted as appropriate.

[0036] The type of the first auxiliary device is not particularly limited, and examples include devices related to water circulation in the fuel cell stack, such as a gas-liquid separator, a humidifier, and an ejector. In addition, the fuel cell unit may have only one first auxiliary device, or may have two or more first auxiliary devices.

[0037] In addition, the fuel cell unit in the present disclosure may have a second auxiliary as an auxiliary. As shown in Figures 7(a) and (b), in the plan view, the entire area C surrounded by the outer edge of the second auxiliary 30B is included inside either the area B1 or the area B2. As shown in Figure 7(a), the entire area C may be included inside the area B1. On the other hand, as shown in Figure 7(b), the entire area C may be included inside the area B2.

[0038] Moreover, the shape of the second auxiliary device in the plan view and the extending direction of the second auxiliary device can be the same as the shape and direction described for the first auxiliary device.

[0039] Examples of the second auxiliary device include devices related to water circulation in the fuel cell stack, such as a gas-liquid separator, a humidifier, and an ejector. The fuel cell unit may have only one second auxiliary device, or may have two or more second auxiliary devices.

[0040] Moreover, it is preferable that the fuel cell unit of the present disclosure does not have any auxiliary components that protrude from area B3, which improves the mountability of the fuel cell unit.

[0041] 4. Fuel Cell Unit The fuel cell unit in the present disclosure may be used in, for example, a vehicle such as a fuel cell electric vehicle (FCEV). The fuel cell unit in the present disclosure may also be used in moving objects other than vehicles (for example, trains, ships, and aircraft), or in objects other than moving objects.

[0042] The present disclosure is not limited to the above-described embodiments. The above-described embodiments are merely examples, and any embodiment that has substantially the same configuration as the technical idea described in the claims of the present disclosure and exhibits similar effects is included in the technical scope of the present disclosure. [Explanation of symbols]

[0043] 10...Fuel cell stack 20...Power converter 30…Auxiliary equipment 30A…1st auxiliary device 30B…Second auxiliary device 40...single cell 100 ... fuel cell unit

Claims

1. A fuel cell stack; a power converter for converting the power of the fuel cell stack; An auxiliary device that assists the operation of the fuel cell stack; A fuel cell unit comprising: the power converter is disposed on a first surface of the fuel cell stack; the auxiliary device is connected to a second surface of the fuel cell stack via a stack manifold; a normal direction of the first surface and a normal direction of the second surface intersect with each other, the fuel cell unit has at least a first auxiliary as the auxiliary, When the fuel cell unit is viewed from the auxiliary device side in a plan view, If the area surrounded by the outer edge of the first accessory is area A, the area surrounded by the outer edge of the fuel cell stack is area B1, the area surrounded by the outer edge of the power converter is area B2, and the combined area of ​​area B1 and area B2 is area B3, The region A overlaps with at least a portion of the region B1 and at least a portion of the region B2, The entirety of the region A is included inside the region B3, A ratio of a portion of the region A that overlaps with the region B1 to the entire region A is 50% or more; the fuel cell unit has a second auxiliary as the auxiliary, In the plan view, when the area surrounded by the outer edge of the second auxiliary device is defined as area C, The entirety of the region C is included within the region B1, The first accessory and the second accessory are each connected to the second surface of the fuel cell stack, a fuel cell unit.

2. 2. The fuel cell unit according to claim 1, wherein the fuel cell unit does not have any auxiliary components that protrude from the region B3.

3. 3. The fuel cell unit according to claim 1, wherein the first auxiliary device is at least one of a gas-liquid separator, a humidifier, and an ejector.

4. the fuel cell unit has a converter and an inverter as the power converter, 3. The fuel cell unit according to claim 1, wherein the converter and the inverter are arranged in this order from the first surface side.

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