CN203178047U - Rapid air tightness detection device for fuel cell stack - Google Patents

Abstract

The utility model discloses a fast air tightness detection device for a fuel cell stack, which comprises a stack and a water pool. The stack is placed in a groove of a fixture in the pool, and the side of the stack with gas inlet and outlet is in contact with the surface at the bottom of the tank. , and use a silicone gasket to seal the gas inlet and outlet parts of the stack. There are two rotatable splints on the fixture. The splints respectively press the plates at both ends of the stack and connect them closely with the main body of the fixture with connecting pieces; the fixture There are three gas pipelines on the top, and the gas passes through the gas pipeline through the fixture and then enters the inside of the stack. The utility model is simple and convenient to install and disassemble, and can not only detect the internal gas leakage of the fuel cell stack, but also detect the external gas leakage.

Description

A fuel cell stack rapid air tightness testing equipment

technical field

The utility model relates to a device for fast air tightness detection of a proton exchange membrane fuel cell stack, which can not only detect the internal gas leakage of the fuel cell stack, but also detect the external gas leakage.

Background technique

A fuel cell is a device that directly converts the chemical energy of an oxidizing agent and a reducing agent into electrical energy through an electrocatalytic reaction. It is an efficient, safe, clean, and flexible new power generation technology. Among them, the proton exchange membrane fuel cell has a wide range of application prospects in ground power stations, electric vehicles and portable power sources due to its remarkable advantages such as high efficiency, high energy density, low reaction temperature, no noise, and no pollution. The interior of the fuel cell is mainly composed of proton exchange membrane, electrochemical reaction catalyst, diffusion layer and bipolar plate. When the fuel cell is working, the following reaction process occurs inside: the reaction gas diffuses in the diffusion layer, and when the reaction gas reaches the catalytic layer, it is adsorbed by the catalyst in the catalytic layer and undergoes an electrocatalytic reaction; the protons generated by the anode reaction pass through the proton The exchange membrane is transferred to the cathode side, and the electrons reach the cathode through the external circuit, react with oxygen molecules to form water, and release heat at the same time. The electrode reaction is:

Anode (negative pole): H2→2H++2e

Cathode (positive electrode): 1/2O2+2H++2e→H2O

Battery reaction: H2+1/2O2→H2O

In a typical proton exchange membrane fuel cell, the membrane electrode is placed between two conductive guide plates, and the two guide plates are respectively the guide plate for the anode fuel and the guide plate for the cathode oxidant. A fuel cell formed in this way is called a single cell. In order to increase the total power of the entire proton exchange membrane fuel cell, multiple single cells need to be stacked in series to form a battery pack, also called a fuel cell stack. In a fuel cell stack, both sides of a polar plate can have guide grooves, one of which can be used as the anode guide surface of one membrane electrode, and the other side can be used as the cathode guide surface of another adjacent membrane electrode. This type of plate is called a bipolar plate. The stack is fastened together by the front end plate, rear end plate and tie rods.

After the fuel cell stack is assembled, an important index of air tightness quality inspection is directly related to the safety and stability of the fuel cell during operation, so the air tightness test is a crucial part in the fuel cell assembly process. Ring, to ensure its correctness and efficiency.

In the actual operation process, it is very tedious and time-consuming to disassemble and assemble the pipeline joints.

The utility model patent with the patent number CN201010562125.5 mentions that the bipolar plate is pressed tightly by the upper and lower molds on the device, and the test gas is passed into the tested component and kept under pressure. air tightness. However, this device only tests the airtightness of the bipolar plate, not the airtightness of the bipolar plate after the bipolar plate is assembled into a stack. The stress situation behind the stack is different, so this device only initially reflects the airtightness of the bipolar plate.

The utility model patent with the patent number CN201010147807.X mentions a device that can automatically feed materials, detect the airtightness of bipolar plates, and automatically sort them. This equipment is used in the production of bipolar plates. When the airtightness is qualified After the bipolar plates are assembled into a stack, the airtightness of the stack may still be unqualified.

The above two patents are only for the airtightness test of one of the parts that make up the electric stack - "bipolar plate", not for the overall airtightness test of the electric stack, because even a single "bipolar plate" The airtightness test of the battery is qualified. When many pieces are assembled into a stack, the airtightness of the stack is not necessarily qualified.

The airtightness test of the stack basically needs to go through the following steps:

1. Install two gas pipeline joints and one coolant pipeline;

2. Introduce gas into the three pipelines in sequence to detect internal leakage of the stack;

3. Place the stack in the water, pass the gas into the three pipelines to detect the leakage of the stack, and replace the bipolar plate or membrane electrode according to the position of the bubble.

In step 1, the operator needs to install 4-6 joints, which takes about several minutes to install, and when the leak test of the stack fails, the pipe joints need to be removed to find out the reason. After completion, the pipe joints need to be installed again , When there is a problem with the airtightness of the stack, it is necessary to repeatedly disassemble and assemble the pipeline joints, which is too much repetitive labor, time-consuming and labor-intensive.

In step 3, the operator needs to place the stack in the pool to detect the leakage of the stack. If the test fails, the pipe joint needs to be removed, and steps 1 and 2 are repeated. The high efficiency of the industrialization of the stack cannot be achieved. Processing production requirements.

Utility model content

Due to the above-mentioned problems in the prior art, the purpose of this utility model is to provide a fast air-tightness testing device for fuel cell stacks, which can solve the above-mentioned problems in the prior art.

In order to achieve the above object, the utility model is realized through the following technical solutions:

A fuel cell stack rapid air tightness testing equipment, including a stack and a water pool, the stack is placed in the tank of a fixture in the pool, and the side of the stack with the gas inlet and outlet is in contact with the bottom surface of the tank, and a silicone pad is used to There are two rotatable splints on the fixture to seal the gas inlet and outlet parts of the stack. The splints respectively press the plates at both ends of the stack and connect them closely with the main body of the fixture with connecting pieces; there are three clamps on the fixture. Gas pipeline, the gas passes through the gas pipeline group, passes through the fixture and then enters the inside of the stack.

As a further feature of the utility model, the connecting piece is a thumb screw.

Due to the adoption of the above technical scheme, the installation and disassembly of a fuel cell stack rapid air tightness detection device of the utility model are simple and convenient, and can detect both internal gas leakage of the fuel cell stack and external gas leakage Condition.

Description of drawings

The utility model will be further described below according to the accompanying drawings and specific embodiments:

Fig. 1 is the sectional view of the front end of the utility model when the stack is not placed

Fig. 2 is the electric stack schematic diagram in the utility model

Fig. 3 is a cross-sectional view of the front end of the utility model when the stack is placed

Among them: 1, water pipeline; 2, gas pipeline group; 3, clamp; 4, water pool; 7, guide groove; 8, contact surface for stack placement; 9, silicone gasket; 10, splint; 11, stack; 12, thumb screw; 13, valve; 14, pressure gauge; 15, drain valve

Detailed ways

As shown in Figures 1, 2, and 3, a fuel cell stack fast airtightness testing device of the present invention, when the device is assembled and used, the stack 11 is first placed on a guide on the fixture 3 in the pool 4 In the groove 7, there is a slope at the mouth of the groove, which is conducive to installation and guidance. The side of the stack 11 with gas inlet and outlet is in contact with the bottom surface of the groove 7. There is a silica gel gasket 9 at the bottom of the groove 7, which is used for the gas inlet and outlet of the stack 11. For the sealing of the outlet position, there are two rotatable splints 10 on the stack fixture 3, and the splint 10 is used to press the plate at one end of the stack 11. There are two thumb screws 12 on the splint 10, which connect the splint 10 with the electric The main body of the stack fixture 3 is connected, and the more it is turned, the tighter it is to enhance the contact tightness between the stack 11 and the stack fixture 3, and then perform the internal leakage detection of the stack 11. There is a gas pipeline group 2 on the stack fixture 3, here are three gases The pipelines are respectively connected to three gas pipelines. Open the gas valve 13 of one of them, and keep the valves of the other two pipelines closed. The gas passes through the pipeline through the stack fixture 3 and then enters the inside of the stack 11. Close the valve and see the intake pipeline. The drop of the pressure gauge 14 is used to judge the gas leakage inside the stack. According to this method, test the other two pipelines respectively. After passing the internal leakage detection of the stack, open the water inlet valve of the water pipeline 1, fill the pool with water, close the valve, open the gas valve of one of the lines, keep the valves of the other two lines closed, and observe whether there are bubbles outside the stack. If there is, you can mark it with a pen, and replace the graphite plate or membrane electrode accordingly. There are transparent windows on the four walls of the pool 4 sides to observe the gas leakage situation on the surface of the stack 11.

The process of taking out the stack is to unscrew the thumb screw 12. There is a nut on the back of the thumb screw 12 to prevent the thumb screw from leaving the splint 10. Unfold the splint 10, take out the stack 11, and then open the drain valve 15 , drain the water.

However, the above-mentioned specific implementations are only exemplary, and are for better understanding of this patent by those skilled in the art, and cannot be interpreted as limiting the scope of this patent; as long as any Equivalent changes or modifications all fall within the scope of this patent.

Claims (2)

1. quick air tightness detection equipment of fuel cell pile, it is characterized in that: comprise pile, pond, pile is positioned in the groove of anchor clamps in the pond, and pile has the one side of gas inlet and outlet to contact with the face of trench bottom, and seal the gas inlet and outlet position of this pile with silica gel pad, anchor clamps are provided with two rotating clamping plate, and these clamping plate make it closely to link to each other with jig main body with web member after pushing down the plate at two ends on the pile respectively; Anchor clamps are provided with three gas pipings, and gas enters pile inside by the gas piping group again through anchor clamps.

2. air tightness detection equipment according to claim 1, it is characterized in that: described web member is hand tighten screw.

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