Bipolar plate of air-cooled hydrogen fuel cell

Abstract

The invention provides an air-cooled hydrogen fuel cell bipolar plate, belongs to the technical field of new energy batteries, and aims to solve the problem of serious excessive supply of reaction air in an air-cooled fuel cell, the air-cooled hydrogen fuel cell bipolar plate comprises a polar plate main body, a plurality of ridge beams distributed in an array are arranged on the positive electrode surface of the polar plate main body, and the ridge beams are hollow rectangular; a cooling flow channel and a reaction flow channel are formed between diffusion layers in contact with a polar plate main body, and the tangent plane of the air inlet end of the ridge is in a horn mouth shape, so that the flow distribution proportion of cooling air and reaction air is effectively adjusted.

Description

Technical Field

[0001] The present invention belongs to the technical field of new energy batteries, and more specifically, particularly relates to an air-cooled hydrogen fuel cell bipolar plate. Background Art

[0002] Proton exchange membrane hydrogen fuel cell (PEMFC) is a power generation device that converts the chemical energy of hydrogen and oxygen into electrical energy. It has the advantages of being clean, efficient, and low noise, and can be widely used in electric vehicles, drones, portable power supplies, etc.

[0003] Based on the heat dissipation method, proton exchange membrane hydrogen fuel cells (hereinafter referred to as hydrogen fuel cells) can be mainly divided into two types: liquid-cooled and air-cooled. Among them, air-cooled hydrogen fuel cells use ambient air as a cooling medium, and use fans to drive the air to flow through the cooling channel. For air-cooled hydrogen fuel cells, ambient air is not only a cooling medium, but also a source of reactant oxygen. Therefore, in order to simplify the battery structure, the cooling air and reaction air supply channels of air-cooled hydrogen fuel cells are usually overlapped or parallel. Ambient air flows through the cathode channel driven by a fan, on the one hand providing the battery with the oxygen required for the reaction, and on the other hand taking away the heat generated by the battery reaction.

[0004] In addition to being gas channels, the flow channels on the metal bipolar plates also play a role in conducting electricity and heat. The cavity structure of the metal bipolar plates allows the cooling air and reaction air channels to be initially separated and parallel to each other. However, since the cooling air and reaction air channels share a fan, the flow rates of the cooling air and reaction air are equivalent. Under high power conditions, the demand for cooling air is more than ten or even dozens of times that of the reaction air. To ensure the heat dissipation effect of the battery, the fan is mainly adjusted according to the demand for cooling air, which results in a serious oversupply of reaction air. Excessive reaction air flow will cause water loss in the membrane electrode and imbalance in water management, ultimately leading to a decline in battery performance and even a reduction in operating life.

[0005] Therefore, in view of this, the existing structure and deficiencies are studied and improved, and an air-cooled hydrogen fuel cell bipolar plate is provided, in order to achieve a more practical purpose. Summary of the invention

[0006] In order to solve the above technical problems, the present invention provides an air-cooled hydrogen fuel cell bipolar plate to solve the problem of severe excess supply of reaction air in the fuel cell.

[0007] The purpose and effect of a hydrogen fuel cell plate of the present invention are achieved by the following specific technical means:

[0008] A hydrogen fuel cell bipolar plate comprises a plate body, wherein a plurality of array-distributed ridges are arranged on the positive electrode surface of the plate body, and the ridges are hollow rectangular, forming cooling channels and reaction channels between the diffusion layers in contact with the plate body, and the cross section of the air inlet end of the ridges is in a trumpet shape.

[0009] Furthermore, triangular blocks are provided on both sides of the end of the ridge beam, so that the inlet of the reaction channel forms a trumpet expansion.

[0010] Furthermore, both ends of the electrode plate body are provided with material passages, and a hydrogen flow channel is distributed on the back of the electrode plate body, and the hydrogen flow channel is connected with the material passage.

[0011] Compared with the prior art, the present invention has the following beneficial effects:

[0012] The air channel inlet on the plate body is changed to a zoom type, so that the cooling air inlet area is larger than the reaction air inlet area, and the flow distribution ratio of cooling air and reaction air is adjusted to ensure that under the condition of large flow heat dissipation of cooling air, the reaction air still maintains the small flow required for appropriate reaction, avoiding excessive moisture in the membrane electrode being blown away by the reaction air. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a stereoscopic diagram of a bipolar plate of an air-cooled hydrogen fuel cell according to the present invention.

[0014] Figure 2 It is a schematic diagram of the planar structure of an air-cooled hydrogen fuel cell bipolar plate of the present invention.

[0015] Figure 3 It is a structural schematic diagram of embodiment 2 of the present invention.

[0016] Figure 4 It is a structural diagram of embodiment 3 of the present invention.

[0017] In the figure, the corresponding relationship between the component names and the figure numbers is as follows:

[0018] 1. Plate body; 2. Feed port; 3. Ridge; 301. Cooling channel; 302. Reaction channel. DETAILED DESCRIPTION

[0019] The following embodiments of the present invention are described in further detail in conjunction with the accompanying drawings and examples. The following examples are used to illustrate the present invention, but are not intended to limit the scope of the present invention.

[0020] In the description of the present invention, unless otherwise specified, "plurality" means two or more than two; the orientations or positional relationships indicated by the terms "upper", "lower", "left", "right", "inner", "outer", "front end", "rear end", "head", "tail", etc. are based on the orientations or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", "third", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0021] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "connected" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0022] Embodiment 1:

[0023] As attached Figure 1 To Attachment Figure 2 As shown:

[0024] The present invention provides an air-cooled hydrogen fuel cell bipolar plate, comprising a plate body 1, a plurality of array-distributed ridges 3 are arranged on the positive electrode surface of the plate body 1, and the ridges 3 are hollow rectangular, forming a cooling flow channel 301 and a reaction flow channel 302 between the diffusion layer in contact with the plate body 1, a hydrogen flow channel is distributed on the back of the plate body 1, and both ends of the plate body 1 extend and are provided with a feed opening 2, and the feed opening 2 and the hydrogen flow channel form a fuel circuit;

[0025] During use, both sides of the plate body 1 contact the gas diffusion layer, the reaction gas enters the gas diffusion layer through the reaction channel 302 to contact the proton exchange membrane, and the cooling channel 301 can take away the heat.

[0026] In order to avoid excessive supply of reaction air, the cross-section of the air inlet end of the spine 3 is in a trumpet-mouth shape. Since the electrode body 1 in this embodiment is a metal bipolar plate, the cooling channel 301 and the reaction channel 302 are separated and parallel to each other. The trumpet-mouth setting changes the reaction channel 302 and the cooling channel 301 into an inlet zoom type, and adjusts the flow distribution ratio of the cooling air and the reaction air. Under the condition of ensuring a large flow rate of cooling air to dissipate heat, the reaction air still maintains a small flow required for an appropriate reaction, thereby avoiding excessive moisture in the membrane electrode being blown away by the reaction air.

[0027] The gap between the cooling channel 301 and the reaction channel 302 is kept in a certain reasonable ratio to avoid reducing the contact area between the reaction air channel and the gas diffusion layer and prevent the effective reaction area from decreasing. The bell-mouth setting only reduces the air intake rate and reduces the water loss in the membrane without affecting the battery performance, thereby extending the battery life.

[0028] Embodiment 2:

[0029] like Figure 3 As shown, the difference between this embodiment and embodiment one is that triangular blocks are arranged on both sides of the end of the ridge beam 3, so that the inlet of the reaction channel 302 forms a trumpet expansion, which reduces the air flow of the reaction channel 302, and has the same effect as the embodiment, but because the inlet of the cooling channel 301 slightly blocks the air flow, embodiment one is taken as the preferred solution.

[0030] Embodiment three:

[0031] like Figure 4 As shown, the difference between this embodiment and the second embodiment is that blocks are provided on both sides of the end of the ridge beam 3, which reduces the inlet width of the reaction channel 302 and does not affect the reaction contact area in the reaction channel 302, and is better than the second embodiment.

[0032] The embodiments of the present invention are given for the purpose of illustration and description, and are not intended to be exhaustive or to limit the invention to the disclosed forms. Many modifications and variations will be apparent to those of ordinary skill in the art. The embodiments are selected and described in order to better illustrate the principles and practical applications of the present invention and to enable those of ordinary skill in the art to understand the present invention and thereby design various embodiments with various modifications suitable for specific uses.

Claims

1. An air-cooled hydrogen fuel cell bipolar plate, characterized in that: The invention comprises an electrode body (1), wherein a plurality of ridges (3) distributed in an array are arranged on the positive electrode surface of the electrode body (1), and the ridges (3) are hollow rectangular, forming a cooling flow channel (301) and a reaction flow channel (302) between the diffusion layer in contact with the electrode body (1), and the air inlet end section of the ridges (3) is in a trumpet shape.

2. An air-cooled hydrogen fuel cell bipolar plate as claimed in claim 1, characterized in that: Triangular blocks are arranged on both sides of the end of the ridge beam (3), so that the inlet of the reaction channel (302) forms a trumpet expansion.

3. The air-cooled hydrogen fuel cell bipolar plate according to claim 1, characterized in that: Both ends of the electrode plate body (1) are provided with material passage openings (2), and a hydrogen flow channel is distributed on the back of the electrode plate body (1), and the hydrogen flow channel is connected to the material passage openings (2).

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