An insulating plate for an air-cooled fuel cell

Abstract

The invention discloses an insulation plate for air-cooled fuel cell stack, which comprises: 1. arc-shaped support formed by a plurality of comb teeth surfaces in a comb structure, which improves the contact inside the stack when the stack is clamped; 2. limiting device for collecting plate and sealing gasket on the insulation plate, which can integrate the insulation plate, collecting plate and sealing gasket together before the stack is assembled; and 3. cooling gas flow channel between the insulation plate and the collecting plate, which facilitates heat dissipation. The invention has simple structure, solves the insulation between the collecting plate and the end plate of the stack, increases the limiting device for the collecting plate and the sealing gasket, makes the contact inside the stack good, and improves the performance of the stack.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of fuel cell, and particularly relates to an insulation plate for air-cooled fuel cell stack. BACKGROUND

[0002] Fuel cell is an energy conversion device, which converts chemical energy stored in fuel gas and oxidant gas into electric energy through electrochemical reaction, and has the advantages of high energy conversion efficiency and less environmental pollution, and has a wide application prospect.

[0003] Generally, a fuel cell single body is composed of a membrane electrode, an anode plate and a cathode plate, a plurality of cell single bodies are connected in series to form a stack, and the generated electricity of the stack is led out from the cathode and anode of the stack by the current collecting plate, thereby forming the positive and negative electrodes of the stack; the current collecting plate of the stack and the end plate of the stack are separated by an insulation plate to prevent the external circuit of the stack from short circuiting. The stack is fastened by bolts or binding belts between the upper and lower end plates.

[0004] According to the type of the bipolar plate used, the fuel cell stack can be divided into graphite plate stack and metal plate stack. The graphite plate has the advantages of good conductivity, good consistency, easy forming and easy processing, but due to its large weight, it is limited in places where the weight of the stack is required. In comparison, the metal plate fuel cell has obvious advantages in weight.

[0005] Fuel cells can be divided into air-cooled fuel cells (hereinafter referred to as air-cooled fuel cells) and liquid-cooled fuel cells according to different cooling methods. Due to the advantages of small size, light weight, fast heat conduction, rapid power supply reaction, cleanliness and no pollution, the air-cooled metal plate fuel cell is popularized and applied in the field of small power supply.

[0006] Since the metal bipolar plate is usually made of stainless steel strip, titanium strip and other materials with a thickness of about 0.1mm by stamping and folding, it is restricted by the level of mold making and processing precision, and there is a certain difference in thickness of the bipolar plate components and products produced; due to the thin material, the rigidity is also poor. There is also a problem of low flatness in the production process of the membrane electrode. Since the stack is composed of a plurality of single cell batteries, the tolerances of each piece of material constituting the stack are accumulated, so that the contact inside the stack is not very sufficient, and poor contact may occur in individual parts. With the increase of the cumulative number of cell single bodies, this problem is more prominent, and the fastening of the stack is also carried out outside the edge of the stack, between the two end plates, which is easy to cause poor internal contact and increase the contact resistance.

[0007] Therefore, the problem of excessive internal stack contact resistance caused by the difference in flatness of the workpiece used needs to be solved on the air-cooled metal plate stack. SUMMARY

[0008] The present application is an air-cooled metal plate fuel cell insulation plate designed to make up for the defects in the existing process manufacturing technology, mainly in the process of stack fastening, so that the stack body part receives more compression force than the fastening part, thereby improving the contact inside the stack body.

[0009] To achieve the purpose, the present application adopts the following technical solutions:

[0010] An air-cooled metal plate fuel cell insulation plate, comprising: an arc-shaped support, a current collecting plate limiting structure, an anode gas inlet and outlet hole, and a sealing gasket limiting structure.

[0011] Characterized in that:

[0012] The arc-shaped support is composed of multiple comb teeth surfaces in a comb structure, the comb tooth height gradually decreases from the middle part to both ends, and the outermost comb tooth is level with the sealing surface on the insulation plate. The comb tooth width is 1-5 mm, the comb tooth height is 1-5 mm, and the comb tooth spacing is 2-5 mm; the upper end surface of the comb tooth is a plane.

[0013] Each comb tooth has a current collecting plate limiting device at both ends, and the limiting structure can be a cube or a cuboid, with a width of 1-5 mm and a height of 1-5 mm. The limiting structure is integrally formed with the insulation plate, and the current collecting plate can be inlaid on the insulation plate.

[0014] The adjacent two comb teeth have a cooling gas flow channel between them, and the spacing between the adjacent two comb teeth is 2-5 mm.

[0015] The insulation plate has fuel gas inlet and outlet holes, and the fuel gas inlet and outlet holes are located on the sealing surface of the insulation plate.

[0016] The insulation plate has a sealing gasket limiting device.

[0017] The insulation plate is made of polyester fiber, bakelite, epoxy resin plate, hard PVC, etc. The beneficial effects of the present application are:

[0018] 1. The insulation plate has a current collecting plate and sealing gasket limiting device, which integrates the current collecting plate and sealing gasket together for easy assembly.

[0019] 2. The arc-shaped support on the insulation plate can make the stack body compression force distribution uniform, improve the contact inside the stack body, and compensate for the influence of processing tolerance.

[0020] 3. The cooling gas channel on the insulation plate is beneficial to heat dissipation of the current collecting plate. BRIEF DESCRIPTION OF DRAWINGS

[0021] The present application is described in the following drawings, in which the same reference numerals are used to designate the same elements, as follows:

[0022] Fig. 1 is a schematic view of the insulation plate structure being implemented; Figure One

[0023] Fig. 2 is a schematic view of the insulation plate not subjected to the clamping force; Figure Two

[0024] Fig. 3 is a schematic view of the insulation plate after clamping; Figure Three

[0025] Fig. 4 is a schematic view of the current collector plate; Figure Four

[0026] Fig. 5 is a schematic view of the insulation plate integrated with the current collector plate and the gasket; Figure Five

[0027] Fig. 6 is a schematic view of the air-cooled fuel cell stack; Figure Six

[0028] Fig. 7 is a schematic view of the stack; Figure Seven

[0029] Reference numeral explanation:

[0030] 10 - fuel cell stack

[0031] 11 - single cell

[0032] 12 - gasket

[0033] 13A, 13C - current collector plate

[0034] 131 - front surface of current collector plate

[0035] 132 - back surface of current collector plate

[0036] 14A, 14C - insulation plate

[0037] 140in - fuel gas inlet hole

[0038] 140out - fuel gas outlet hole

[0039] 141 - cooling gas passage

[0040] 142 - current collector plate stopper

[0041] 143 - upper surface of comb tooth

[0042] 144 - sealing surface

[0043] 145 - gasket stopper

[0044] 146 - upper surface of comb tooth

[0045] ​​​​​​​15A, 15C - End Plate

[0046] 16A, 16C - Fastening Bolts

[0047] 17-Fastening Rod

[0048] 18-Stacked Body

[0049] 19in-Fuel Gas Supply Manifold

[0050] 19out-Fuel gas exhaust manifold Detailed Implementation

[0051] The present invention will be described in more detail below with reference to implementation cases and examples.

[0052] Example:

[0053] Figure One This is a schematic diagram of the insulation board structure. The entire insulation board 14A consists of a fuel gas inlet 140 in...

[0054] It consists of a fuel gas outlet 140out, a cooling gas channel 141, a current collector plate limiting device 142, comb teeth 143, inner end face of comb teeth 146, and a sealing surface 144. Each comb tooth 143 has protruding structures at both ends of its upper surface, forming a limiting device 142 for the current collector plate 13A. A cooling gas channel 141 is left between two adjacent comb teeth. The channel depth is lower than the sealing surface 144. The height from the inner end face 146 of the middle comb tooth 143 to the bottom surface of the cooling gas channel 141 is the greatest. The height of the inner end face 146 of the other comb teeth gradually decreases towards the fuel gas inlet, outlet, and vent holes 140in and 140out, respectively, forming an arc-shaped support surface structure. A fuel gas inlet hole 140in and a fuel gas outlet hole 140out are left on the insulating plate for the fuel gas inlet and outlet. The fuel gas inlet, outlet, and vent holes 140in and 140out are located on the sealing surface 144, and the sealing gasket 12 is limited by the sealing gasket limiting device 145.

[0055] Figure Two This diagram shows an insulating plate without clamping force. The schematic diagram, viewed from direction E, shows the insulating plate 14A without clamping force. In the diagram, T3 is the height from the sealing surface 144 to the bottom surface of the cooling gas channel 141, which is also the height from the inner end face of the outermost comb tooth to the bottom surface of the cooling gas channel 141. T1 is the height from the inner end face of the middle comb tooth to the bottom surface of the cooling gas channel 141. T2 is the height from the inner end face of the comb tooth between the middle and outermost comb teeth to the bottom surface of the cooling gas channel 141. T1 > T2 > T3, thus forming an arc-shaped support surface on the insulating plate 14A.

[0056] Figure ThreeThe figure shows the insulation plate after clamping. T1, T2 and T are in the same plane.

[0057] Figure Four The figure shows the collector plate. The collector plate is made of metal plate with high strength and good conductivity. The front side of the collector plate (the side in contact with the stack) is treated for corrosion prevention.

[0058] Figure Five The figure shows the insulation plate with integrated collector plate and gasket. The collector plate 13A and the gasket 12 are integrated on the insulation plate 14A. The cooling gas passage 141 formed between the collector plate 13A and the insulation plate 14A can be used for heat dissipation of the collector plate 13A.

[0059] Figure Six The figure shows the exploded structure of the air-cooled battery stack. A plurality of single cells 11 are stacked to form a stack 18. The stack 18 is assisted by the collector plates 13A and 13C, the insulation plates 14A and 14C, and the end plates 15A and 15C on the upper and lower sides of the stack 18. The air-cooled battery stack 10 is formed by the fastening of the fastening bolts 16A and 16C and the fastening rods 17.

[0060] Figure Seven The figure shows the air-cooled battery stack product. The internal contact resistance of the product is significantly reduced compared to the same type of product using ordinary insulation plates under the same clamping force.

[0061] The above embodiments only express the implementation of the present application, and the description is more specific and detailed, but it should not be understood as a limitation on the scope of the present application. It should be noted that for ordinary skilled in the art, without departing from the concept of the present application, a number of modifications and improvements can be made, which are within the scope of the present application.

Claims

1. An insulation plate for air-cooled fuel cells, comprising fuel gas inlet holes, fuel gas outlet holes, coolant channels, current collector plate positioning devices, comb-shaped tooth upper surfaces near the end portions, comb-shaped tooth upper surfaces near the center portion, sealing surfaces, and gasket positioning devices; the current collector plate positioning devices are provided on the comb-shaped tooth upper surfaces at both ends in the direction of the coolant channels; the gasket positioning devices are provided on the sealing surfaces at both ends in the direction of the coolant channels; the fuel gas inlet holes and the fuel gas outlet holes are provided on the sealing surfaces at both ends of the insulation plate; the insulation plate, the current collector plate, and two gaskets are positioned and integrated together by the current collector plate positioning devices and the gasket positioning devices; the comb-shaped tooth upper surfaces near the center portion are at a height T1 from the bottom surface of the coolant channels, the comb-shaped tooth upper surfaces near the end portions are at a height T3 from the bottom surface of the coolant channels, and any one of the comb-shaped tooth upper surfaces is at a height T2 from the bottom surface of the coolant channels, wherein when the insulation plate is not subjected to clamping force, the values of T1, T2, and T3 are in the order of T1 > T2 > T3, and when the insulation plate is subjected to clamping force, the values of T1, T2, and T3 are in the order of T1 ≈ T2 ≈ T3; the insulation plate is made of polyester fiber, bakelite, epoxy resin plate, or hard PVC insulation material. Each comb-shaped tooth upper surface is provided with a current collector plate positioning device at both ends in the direction of the coolant channels, the comb-shaped tooth upper surfaces are attached to the current collector plate, and the comb-shaped tooth upper surfaces and the current collector plate constitute a coolant flow channel. ​ ​ ​ characterized in that ​ ​ 2. An insulation sheet for an air-cooled fuel cell according to claim 1, characterized in that: ​

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