Fuel cell end plate

Abstract

The present invention discloses a fuel cell end plate, comprising an outer plate and a flow equalizing plate, wherein a fluid flows through the outer plate and the flow equalizing plate in sequence, wherein the outer plate is provided with a total fluid inlet, wherein the flow equalizing plate is provided with a groove and a plurality of manifold inlets with different widths, wherein the plurality of manifold inlets are connected to the bottom of the groove, wherein the total fluid inlet is connected to the groove, and the manifold inlet is connected to the bottom of the groove. The present invention improves the uniformity of fluid distribution in each manifold by providing manifold inlets of different widths, without introducing an additional device for fluid distribution, and has a simple structure and is convenient for implementation.

Description

Technical Field

[0001] The present invention relates to the technical field of fuel cells, and in particular to an end plate of a fuel cell. Background Art

[0002] A fuel cell is a power generation system that uses electrochemical methods to directly convert chemical energy into electrical energy in a fuel cell stack, rather than converting the chemical energy of the fuel into heat through combustion. Fuel cells can be applied not only to industry, household appliances and vehicles, but also to the power supply of small-scale power and electronic equipment such as portable devices. A fuel cell usually has two sets of upper and lower end plates, between which is a stacking structure formed by stacking multiple single cells layer by layer. The upper and lower end plates are connected together by tie rods or bandages to maintain the pressure of the cells in the stack. The stacking structure usually forms one or more oxidant supply manifolds, one or more fuel supply manifolds, and one or more coolant supply manifolds, which are respectively connected to the oxidant inlet, fuel inlet, and coolant inlet provided on the end plates. Usually, the fuel needs to be evenly distributed to different fuel supply manifolds. Similar oxidants need to be evenly distributed to different oxidant supply manifolds, and coolants need to be evenly distributed to different coolant supply manifolds.

[0003] Patent CN 1717829A discloses a fuel cell end plate, wherein the top surface of the end plate is provided with reactant and coolant inlets, and the bottom surface of the end plate is provided with openings connected to the fuel cell stack structure manifold. Reactants and coolants can be introduced into the end plate and can enter the fuel cell through these openings.

[0004] Patent CN 1717829A solves the problem of fluid introduction into the stack. However, in the case of multiple oxidant supply manifolds, multiple fuel supply manifolds, or multiple coolant supply manifolds, the manifold close to the total fluid inlet has a large flow rate, while the manifold far from the total fluid inlet has a small flow rate. The problem of uneven flow distribution between the same manifolds is obvious. Uneven distribution of fuel and oxidant causes uneven current density; and uneven distribution of coolant easily causes uneven heat dissipation and large temperature differences. These in turn affect the performance of the stack.

[0005] In view of this, overcoming the defects of the above-mentioned prior art is an urgent problem to be solved in this field. Summary of the invention

[0006] In order to overcome the technical problems in the prior art that in the case of multiple oxidant supply manifolds, or multiple fuel supply manifolds, or multiple coolant supply manifolds, the flow rate of the manifold close to the total fluid inlet is large, while the flow rate of the manifold far from the total fluid inlet is small, and the flow distribution between the same manifolds is uneven, the present invention provides a fuel cell end plate that ensures uniform flow distribution between the same manifolds in the case of multiple oxidant supply manifolds, or multiple fuel supply manifolds, or multiple coolant supply manifolds.

[0007] In order to achieve the above-mentioned purpose, the present invention discloses a fuel cell end plate, including an outer plate and a flow equalizing plate, the fluid flows through the outer plate and the flow equalizing plate in sequence, the outer plate is provided with a total fluid inlet, the flow equalizing plate is provided with a groove and a plurality of manifold inlets, the total fluid inlet is connected to the groove, and the plurality of manifold inlets are connected to the bottom of the groove.

[0008] Furthermore, the ratio of the thickness of the flow equalizing plate to the depth of the groove is not less than 1.5.

[0009] Furthermore, the distances between adjacent manifold inlets are the same.

[0010] Furthermore, the manifold inlets are symmetrically distributed along the axis of the total fluid inlet and at least one manifold inlet corresponds to the total fluid inlet. The width of the manifold inlet gradually decreases from close to the axis of the total fluid inlet to far away from the axis of the total fluid inlet.

[0011] Furthermore, the width ratio of adjacent manifold inlets is not greater than 1.5 and not less than 1.1.

[0012] The fuel cell end plate provided by the present invention improves the uniformity of fluid distribution in each manifold by arranging manifold inlets of different widths without introducing additional devices for fluid distribution, has a simple structure, and is easy to implement. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] The accompanying drawings, which are included in and constitute a part of this specification, illustrate embodiments of the apparatus and method consistent with the present invention and, together with the detailed description, are used to explain the advantages and principles of the present invention. In the drawings:

[0014] Figure 1 It is a schematic diagram of the structure of the fuel cell end plate.

[0015] Description of Reference Numerals

[0016] 1-Outer plate

[0017] 2- Current balancing plate

[0018] 3- Total fluid import

[0019] 4-Manifold Inlet

[0020] 41-First manifold inlet

[0021] 42-Second manifold inlet

[0022] 43-Third manifold inlet

[0023] 44-Fourth manifold inlet

[0024] 45-Fifth manifold inlet

[0025] 5-Inside the battery stack

[0026] 6-Grooves

[0027] E-Manifold inlet width

[0028] E1-1st manifold inlet width

[0029] E2-Second manifold inlet width

[0030] E3-Third manifold inlet width

[0031] E4-Fourth manifold inlet width

[0032] E5-Fifth manifold inlet width

[0033] D- total fluid inlet width

[0034] H-Outer plate thickness

[0035] f - groove depth

[0036] h-thickness of the flow plate

[0037] L - distance between adjacent manifold inlets DETAILED DESCRIPTION

[0038] The specific embodiments of the present invention are described in detail below in conjunction with the accompanying drawings. However, the present invention is not limited to the embodiments described below. In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other, and the technical concept of the present invention can be implemented in combination with other known technologies or other technologies that are the same as those known technologies.

[0039] like Figure 1 As shown, a fuel cell end plate includes an outer plate 1 and a flow equalizing plate 2. The fluid flows through the outer plate 1 and the flow equalizing plate 2 in sequence. A sealing ring is provided between the outer plate 1 and the flow equalizing plate 2 to prevent leakage of the fluid. The fluid here includes fuel, oxidant, or coolant.

[0040] The outer plate 1 is provided with a total fluid inlet 3, and the flow equalizing plate 2 is provided with a groove 6. One end of the total fluid inlet 3 is connected to the external fluid pipeline, and the other end is connected to the groove 6. The thickness of the flow equalizing plate 2 is h, the depth of the groove 6 is f, and the value of h / f is not less than 1.5. The flow equalizing plate 2 is also provided with a plurality of manifold inlets 4 of different widths, and the cross section of the manifold inlet 4 is circular. One end of the plurality of manifold inlets 4 is connected to the inside of the stack 5, and the other end is connected to the bottom of the groove 6.

[0041] The arrangement of the manifold inlets 4 on the flow equalizing plate 2 is as follows: the first manifold inlet 41 corresponds to the total fluid inlet 3, and the other manifold inlets 42, 43, 44, 45 are symmetrically distributed along the axis of the total fluid inlet 3, and the distance L between all adjacent manifold inlets 4 is the same.

[0042] The above situation is the case where the manifold inlet 4 is odd in number. When the manifold inlet 4 is even in number, the arrangement of the manifold inlet 4 on the flow equalizing plate 2 is as follows: at least 2 manifold inlets 4 correspond to the total fluid inlet 3, and the other manifold inlets 4 are symmetrically distributed along the axis of the total fluid inlet 3.

[0043] In addition, the widths E of several manifold inlets 4 are different, the manifold inlets 4 closer to the fluid main inlet 3 are smaller in width, and the manifold inlets 4 farther from the fluid main inlet 3 are larger in width, such as E1 < E2 = E3 < E4 = E5. In addition, the width ratio of adjacent manifold inlets 4 is not greater than 1.5 and not less than 1.1.

[0044] Compared with the prior art, the fuel cell end plate provided by the present invention improves the uniformity of fluid distribution in each manifold by setting manifold inlets of different widths without introducing additional devices for fluid distribution, and has a simple structure and is easy to implement.

[0045] Unless otherwise specified, qualifiers such as "first" and "second" appearing in this document do not refer to limitations on time sequence, quantity, or importance, but are merely used to distinguish one technical feature from another in the technical solution. Similarly, modifiers such as "approximately" and "approximately" that appear before a numeral in this document usually include the number itself, and their specific meanings should be understood in conjunction with the context. Similarly, unless it is a noun modified by a specific quantitative quantifier, it should be regarded as including both singular and plural forms in this document, and the technical solution may include both the singular and plural technical features.

[0046] In the description of the above specific embodiments, the use of directional terms such as "up", "down", "left", "right", "top", "bottom", "vertical", "horizontal" and "lateral" are merely for the purpose of convenience of description and should not be regarded as limiting.

[0047] Although the specific embodiments of the present invention are described above, those skilled in the art should understand that these are only examples, and the protection scope of the present invention is defined by the appended claims. Those skilled in the art may make various changes or modifications to these embodiments without departing from the principles and essence of the present invention, but these changes and modifications all fall within the protection scope of the present invention.

Claims

1. A fuel cell end plate, characterized in that: It comprises an outer plate and a flow equalizing plate, the fluid flows through the outer plate and the flow equalizing plate in sequence, the outer plate is provided with a total fluid inlet, the flow equalizing plate is provided with a groove and a plurality of manifold inlets with different widths, the total fluid inlet is connected with the groove, and a plurality of the manifold inlets are connected with the bottom of the groove; The ratio of the thickness of the flow equalizing plate to the depth of the groove is not less than 1.5; The width of the manifold inlet gradually decreases from close to the axis of the total fluid inlet to far away from the axis of the total fluid inlet, and the width ratio of adjacent manifold inlets is not greater than 1.5 and not less than 1.

1.

2. The fuel cell end plate according to claim 1, characterized in that: The distances between adjacent manifold inlets are the same.

3. The fuel cell end plate according to claim 2, characterized in that: The manifold inlets are symmetrically distributed along the axis of the total fluid inlet, and at least one manifold inlet corresponds to the total fluid inlet.

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