Membrane electrode, electric pile and vehicle

Abstract

The invention relates to the technical field of fuel cells, in particular to a membrane electrode, an electric pile and a vehicle, the membrane electrode comprises a body and a frame, the body is arranged on the frame, a plurality of channels are formed in the position, not provided with the body, of the frame, and gap bridge areas are arranged between the channels and the body; the gap bridge area is subjected to thickening treatment; the supporting effect is guaranteed by adjusting the local structure of the gap bridge area, the stack loading force consistency of the stack can be improved, the risk of sealing failure caused by easy deformation of the polar plate and stress deformation and cracking of the frame is effectively solved, the mechanical property is improved by thickening and reducing the deformation amount, the service life is prolonged, and the cost is reduced. The risk of rapid plastic deformation of the polar plate under stress in the prior art is overcome; and the contact area is reduced after the membrane electrode frame is deformed under stress, and the risk of sealing failure caused by frame cracking due to overlarge local contact stress is avoided.

Description

Technical Field

[0001] The present invention relates to the technical field of fuel cells, and in particular to a membrane electrode, a fuel cell stack, and a vehicle. Background Art

[0002] A fuel cell stack is a finished product that is assembled by stacking bipolar plates and membrane electrodes in sequence onto pre-assembled structural parts (end plates, current collecting plates, insulating plates, etc.). When assembling the stack, a press will be used to apply a certain amount of pressure to the stack through the end plates to compress the stack to ensure airtightness and performance.

[0003] The existing technical solutions only consider the force uniformity of the seal and bipolar plate distribution area, active area, and sealing area during stacking, but do not consider the potential risk of plastic deformation caused by uneven force distribution in the plate bridge area and the risk of seal failure caused by reduced contact area after the membrane electrode frame is deformed by force, and excessive local contact stress leading to frame cracking; refer to Figure 1 and Figure 2 ,With the development of technology, the substrate thickness of metal bipolar plates is getting thinner and thinner, and the uneven ,force distribution makes it more susceptible to plastic deformation.

[0004] Depend on Figure 1 It can be seen that the force on the plates is not uniform during stack assembly. The left area in the figure is the alignment area, where the force is vertically distributed, and the right area is the dislocation area, where the force is "Z"-shaped. This force will cause local plastic deformation of the plates. The simulation results of the dislocation area are shown in Figure 2 . Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide a membrane electrode, a battery stack and a vehicle which can improve the consistency of the stacking force and effectively solve the risk of sealing failure caused by plate deformation and frame deformation and cracking due to stress.

[0006] In order to solve the above technical problems, the first technical solution adopted by the present invention is:

[0007] A membrane electrode, comprising a body and a frame, wherein the body is arranged on the frame, a plurality of channels are provided at a position other than the body, and a bridge region is provided between the channels and the body;

[0008] The bridge area is thickened, and the calculation formula of the thickened thickness h is:

[0009] h=[a / 2+b+c*(1-d)-e]*f

[0010] Among them, a is the thickness of the proton exchange membrane of the membrane electrode; b is the thickness of the catalyst on one side of the membrane electrode; c is the thickness of the carbon paper on one side of the membrane electrode; d is the compression rate of the carbon paper of the membrane electrode; e is the single-side thickness of the membrane electrode frame; and f is the safety factor.

[0011] Preferably, the value of d is 25%.

[0012] Preferably, the value of f is 0.5 to 0.7;

[0013] Preferably, the thickening treatment is the thickening of one side of the bridge area.

[0014] In order to solve the above technical problems, the second technical solution adopted by the present invention is:

[0015] A battery stack comprises the above-mentioned membrane electrode.

[0016] In order to solve the above technical problems, the third technical solution adopted by the present invention is:

[0017] A battery stack, comprising bipolar plates and membrane electrodes arranged in a staggered manner; the membrane electrode comprises a body and a frame, a plurality of channels are provided on the frame where the body is not provided, and a bridge area is provided between the channel and the body;

[0018] The two side surfaces of the bridge area are provided with gaskets respectively, and the thickness h of the gaskets is calculated by the formula:

[0019] h=[a / 2+b+c*(1-d)-e]*f

[0020] Among them, a is the thickness of the proton exchange membrane of the membrane electrode; b is the thickness of the catalyst on one side of the membrane electrode; c is the thickness of the carbon paper on one side of the membrane electrode; d is the compression rate of the carbon paper of the membrane electrode; e is the single-side thickness of the membrane electrode frame; and f is the safety factor.

[0021] In order to solve the above technical problems, the fourth technical solution adopted by the present invention is:

[0022] A battery stack, comprising bipolar plates and membrane electrodes arranged in a staggered manner; the membrane electrode comprises a body and a frame, a plurality of channels are provided on the frame where the body is not provided, and a bridge area is provided between the channel and the body;

[0023] There are raised portions on both sides of the bipolar plate corresponding to the bridge area, and the height h of the raised portion is calculated as follows:

[0024] h=[a / 2+b+c*(1-d)-e]*f

[0025] Among them, a is the thickness of the proton exchange membrane of the membrane electrode; b is the thickness of the catalyst on one side of the membrane electrode; c is the thickness of the carbon paper on one side of the membrane electrode; d is the compression rate of the carbon paper of the membrane electrode; e is the single-side thickness of the membrane electrode frame; and f is the safety factor.

[0026] In order to solve the above technical problems, the fifth technical solution adopted by the present invention is:

[0027] A vehicle comprises the above-mentioned battery stack.

[0028] The beneficial effects of the present invention are as follows: by adjusting the local structure of the bridge area to ensure the supporting effect, the consistency of the stacking force can be improved, and the risk of easy deformation of the plate and deformation and cracking of the frame due to stress can be effectively solved. By thickening, the deformation amount is reduced, thereby improving the mechanical properties and extending the service life, and overcoming the risk of rapid plastic deformation of the plate under stress in the prior art; and the contact area of ​​the membrane electrode frame is reduced after the deformation under stress, and the risk of sealing failure caused by excessive local contact stress leading to cracking of the frame. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 It is a schematic diagram of the force on the plates when assembling the battery stack in the prior art;

[0030] Figure 2 This is a simulation effect diagram of the stress on the battery stack assembly in the prior art;

[0031] Figure 3 A schematic diagram of the structure of a membrane electrode according to a specific embodiment of the present invention;

[0032] Figure 4 This is a simulation effect diagram of a membrane electrode application according to a specific embodiment of the present invention;

[0033] Explanation of reference numerals: 10, gasket; 11, bridge area. DETAILED DESCRIPTION

[0034] In order to explain the technical content, achieved objectives and effects of the present invention in detail, the following is an explanation in combination with the implementation modes and the accompanying drawings.

[0035] Embodiment 1

[0036] A membrane electrode, comprising a body and a frame, wherein the body is arranged on the frame, a plurality of channels are provided at a position other than the body, and a bridge region is provided between the channels and the body;

[0037] The bridge area 11 is thickened, and the calculation formula of the thickened thickness h is:

[0038] h=[a / 2+b+c*(1-d)-e]*f

[0039] Among them, a is the thickness of the proton exchange membrane of the membrane electrode; b is the thickness of the catalyst on one side of the membrane electrode; c is the thickness of the carbon paper on one side of the membrane electrode; d is the compression rate of the carbon paper of the membrane electrode; e is the single-side thickness of the membrane electrode frame; and f is the safety factor.

[0040] The selected value of d is 25%.

[0041] The value of f is 0.5 to 0.7;

[0042] The thickening treatment is the thickening thickness of one side of the bridge area.

[0043] Embodiment 2

[0044] A battery stack comprises the membrane electrode described in the first embodiment.

[0045] Embodiment 3

[0046] A battery stack, comprising bipolar plates and membrane electrodes arranged in a staggered manner; the membrane electrode comprises a body and a frame, a plurality of channels are provided on the frame where the body is not provided, and a bridge area is provided between the channel and the body;

[0047] The two side surfaces of the bridge area are provided with gaskets 10 respectively, and the thickness h of the gaskets is calculated by the formula:

[0048] h=[a / 2+b+c*(1-d)-e]*f

[0049] Among them, a is the thickness of the proton exchange membrane of the membrane electrode; b is the thickness of the catalyst on one side of the membrane electrode; c is the thickness of the carbon paper on one side of the membrane electrode; d is the compression rate of the carbon paper of the membrane electrode; e is the single-side thickness of the membrane electrode frame; and f is the safety factor.

[0050] Embodiment 4

[0051] A battery stack, comprising bipolar plates and membrane electrodes arranged in a staggered manner; the membrane electrode comprises a body and a frame, a plurality of channels are provided on the frame where the body is not provided, and a bridge area is provided between the channel and the body;

[0052] There are raised portions on both sides of the bipolar plate corresponding to the bridge area, and the height h of the raised portion is calculated as follows:

[0053] h=[a / 2+b+c*(1-d)-e]*f

[0054] Among them, a is the thickness of the proton exchange membrane of the membrane electrode; b is the thickness of the catalyst on one side of the membrane electrode; c is the thickness of the carbon paper on one side of the membrane electrode; d is the compression rate of the carbon paper of the membrane electrode; e is the single-side thickness of the membrane electrode frame; and f is the safety factor.

[0055] Embodiment 5

[0056] A vehicle, comprising the fuel cell stack described in any one of embodiments 2 to 4.

[0057] The above descriptions are merely embodiments of the present invention and are not intended to limit the patent scope of the present invention. Any equivalent transformations made using the contents of the present invention's specification and drawings, or directly or indirectly applied in related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A membrane electrode, characterized in that: It comprises a body and a frame, wherein the body is arranged on the frame, a plurality of channels are provided at a position other than the body, and a bridge area is provided between the channels and the body; The bridge area is thickened, and the calculation formula of the thickened thickness h is: h=[a / 2+b+c*(1-d)-e]*f Among them, a is the thickness of the proton exchange membrane of the membrane electrode; b is the thickness of the catalyst on one side of the membrane electrode; c is the thickness of the carbon paper on one side of the membrane electrode; d is the compression rate of the carbon paper of the membrane electrode; e is the single-side thickness of the membrane electrode frame; and f is the safety factor.

2. The membrane electrode according to claim 1, characterized in that: The selected value of d is 25%.

3. The membrane electrode according to claim 1, characterized in that: The selected value of f is 0.5 to 0.

7.

4. The membrane electrode according to claim 1, characterized in that: The thickening treatment is the thickening thickness of one side of the bridge area.

5. A battery stack, characterized in that: A membrane electrode comprising any one of claims 1 to 4.

6. A battery stack, characterized in that: It includes bipolar plates and membrane electrodes arranged in a staggered manner; the membrane electrode includes a body and a frame, a plurality of channels are provided on the frame where the body is not arranged, and a bridge area is provided between the channel and the body; The two side surfaces of the bridge area are provided with gaskets respectively, and the thickness h of the gaskets is calculated by the formula: h=[a / 2+b+c*(1-d)-e]*f Among them, a is the thickness of the proton exchange membrane of the membrane electrode; b is the thickness of the catalyst on one side of the membrane electrode; c is the thickness of the carbon paper on one side of the membrane electrode; d is the compression rate of the carbon paper of the membrane electrode; e is the single-side thickness of the membrane electrode frame; and f is the safety factor.

7. A battery stack, characterized in that: It includes bipolar plates and membrane electrodes arranged in a staggered manner; the membrane electrode includes a body and a frame, a plurality of channels are provided on the frame where the body is not arranged, and a bridge area is provided between the channel and the body; There are raised portions on both sides of the bipolar plate corresponding to the bridge area, and the height h of the raised portion is calculated as follows: h=[a / 2+b+c*(1-d)-e]*f Among them, a is the thickness of the proton exchange membrane of the membrane electrode; b is the thickness of the catalyst on one side of the membrane electrode; c is the thickness of the carbon paper on one side of the membrane electrode; d is the compression rate of the carbon paper of the membrane electrode; e is the single-side thickness of the membrane electrode frame; and f is the safety factor.

8. A vehicle, characterized in that: A battery stack comprising any one of claims 5 to 7.

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