阅读说明：本技术 用于燃料电池的可调式应力结构 (Adjustable stress structure for fuel cell ) 是由 林志嘉 黄靖颖 徐子轩 李钧函 吴佩蓉 于 2019-11-26 设计创作，主要内容包括：一种用于燃料电池的可调式应力结构,包括一第一压力端板、第一组弹簧、第一组导引杆、一燃料电池、多个第一压力旋钮以及多个锁固件。燃料电池具有一第一电池端板和一第二电池端板。第一压力端板具有多个第一槽孔。第一组弹簧设置于第一电池端板与第一压力端板之间。第一组导引杆分别贯穿第一组弹簧并连接第一电池端板与该第一压力端板。多个第一压力旋钮设置于第一压力端板的该第一槽孔内与该第一组导引杆上方,通过调节该第一压力旋钮来调整该第一组弹簧的应力,使得燃料电池内部应力均匀分布。(An adjustable stress structure for a fuel cell includes a first pressure end plate, a first set of springs, a first set of guide rods, a fuel cell, a plurality of first pressure knobs, and a plurality of locking members. The fuel cell has a first cell end plate and a second cell end plate. The first pressure end plate is provided with a plurality of first slotted holes. The first set of springs is disposed between the first cell end plate and the first pressure end plate. The first group of guide rods respectively penetrate through the first group of springs and are connected with the first battery end plate and the first pressure end plate. The first pressure knobs are arranged in the first slot holes of the first pressure end plate and above the first group of guide rods, and the stress of the first group of springs is adjusted by adjusting the first pressure knobs, so that the internal stress of the fuel cell is uniformly distributed.)

1. An adjustable stress structure for a fuel cell, comprising:

a fuel cell for converting chemical energy in a fuel into electrical energy, the fuel cell having a first cell end plate and a second cell end plate;

a first pressure end plate having a plurality of first slots;

a first set of springs disposed between the first cell end plate and the first pressure end plate;

the first group of guide rods respectively penetrate through the first group of springs and connect the first battery end plate and the first pressure end plate;

a plurality of first pressure knobs disposed in the first slots of the first pressure end plate and above the first set of guide rods; and

a plurality of fasteners for fixing the first pressure end plate, the first battery end plate and the second battery end plate,

and the stress of the first group of springs is adjusted by adjusting the first pressure knob, so that the internal stress of the fuel cell is uniformly distributed.

2. The adjustable stress structure for a fuel cell according to claim 1, further comprising:

a second pressure end plate having a plurality of second slots;

a second set of springs disposed between the second cell end plate and the second pressure end plate;

a second set of guide rods, each of which penetrates through the second set of springs and connects the second battery end plate and the second pressure end plate; and

a plurality of second pressure knobs arranged in the second slot holes of the second pressure end plate and above the second group of guide rods,

wherein, the locking piece is also used for fixing the second pressure end plate;

and the stress of the second group of springs is adjusted by adjusting the second pressure knob, so that the internal stress of the fuel cell is uniformly distributed.

3. The adjustable stress structure for a fuel cell according to claim 1, further comprising:

a second pressure end plate;

wherein, the locking part is also used for fixing the second pressure end plate.

4. The adjustable stress structure for fuel cells according to any one of claims 1 to 3, wherein the fuel cell has a plurality of through holes, and the locking member is used to fix the fuel cell through the through holes.

5. The adjustable stress structure for fuel cells according to claim 2, wherein the first set of springs and the second set of springs are springs with the same or different elastic coefficients.

6. The adjustable stress structure for a fuel cell of claim 2 or 3, wherein at least one of the first pressure end plate and the second pressure end plate is X-shaped.

7. The adjustable stress structure for fuel cells according to claim 2 or 3, wherein the first pressure end plate or the second pressure end plate is made of aluminum alloy, magnesium alloy, titanium alloy or plastic steel.

8. The adjustable stress structure for a fuel cell according to any one of claims 1 to 3, wherein the fuel cell is a single fuel cell or a plurality of fuel cells.

9. The adjustable stress structure for the fuel cell as set forth in claim 1, comprising the steps of:

measuring a raw impedance value of the fuel cell;

adjusting the first pressure knob according to the original impedance value;

measuring the impedance value of the fuel cell after adjusting the first pressure knob; and

confirming the stress distribution of the fuel cell after adjusting the first pressure knobs.

10. A method of modulating stress for an adjustable stress structure for a fuel cell as defined in claim 3, comprising the steps of:

measuring a raw impedance value of the fuel cell;

adjusting the first pressure knob and the second pressure knob according to the original impedance value;

measuring the impedance value of the fuel cell after adjusting the first pressure knob and the second pressure knob; and

confirming the stress distribution of the fuel cell after adjusting the first pressure knob and the second pressure knob.

Technical Field

The present invention relates to a fuel cell assembly module, and more particularly, to an adjustable stress structure for a fuel cell.

Background

A Membrane Electrode Assembly (MEA), a key component of a Proton Exchange Membrane Fuel Cell (PEMFC), mainly comprises two catalyst layers (anode and cathode) and a solid polymer electrolyte Membrane. The anode and cathode are separated by a solid proton exchange membrane. The outer sides of the two catalyst layers are respectively adhered with a porous gas diffusion layer, and the outer sides of the gas diffusion layers are provided with bipolar plates with fluid channels. Hydrogen is continuously supplemented to the anode, oxygen is continuously supplemented to the cathode, oxidation-reduction reaction occurs on the electrode, protons reach the cathode through the electrolyte membrane, electrons reach the cathode from the anode through an external load to complete a current loop, and the reacted product water, unreacted hydrogen and oxygen are discharged through an electrode outlet. The conventional process for assembling a fuel cell is to stack all components including an end plate, a collector plate, a unipolar plate, a bipolar plate, and a membrane electrode assembly. In order to make the fuel cell more compact and lightweight, to increase its power density and to facilitate various product applications, the design requirements of the next generation fuel cell have gradually developed towards a trend of being light, thin and small. Since the bipolar plates occupy a large portion of the volume and weight of the stack. Therefore, no matter the designer using the composite carbon plate or the metal plate as the bipolar plate, the thin plate is adopted as much as possible to improve the compactness and the light weight of the battery pack. The metal bipolar plate has the technical characteristics and advantages that the flow channel is formed at one time, the cost is low, and the metal bipolar plate is suitable for mass production; the mechanical property is high, the air tightness is good, and the battery can bear strong pressure during the assembly without damage; the design of the thin plate can reach 0.08-0.2mm in thickness, greatly reduce the volume and weight of the battery, and increase the application chance and competitive advantage of the product.

Figure 1 is a schematic diagram of a prior art fuel cell module. As shown in fig. 1, a fuel cell module 1 has a fuel cell 2, an upper cell end plate 4, a lower cell end plate 6, and a plurality of screws 8. The assembly pressure of the fuel cell module 1 tends to accumulate large stress at the screw 8 lock, causing the upper cell end plate 4 and the lower cell end plate 6 to deform and bend. In addition, stress-strain control in the fuel cell assembly process is critical to how electrochemical reactions within the cell can proceed uniformly without local hot spots, which can affect cell performance and cell life.

In order to solve the above problems, an adjustable stress structure for a fuel cell is needed, which can prevent the cell end plate from deforming and bending, and can control the local assembly stress of the fuel cell, so as to make the internal stress of the fuel cell uniform.

Disclosure of Invention

The invention aims to provide an adjustable stress structure for a fuel cell, which uses a plurality of springs with high elastic coefficient, a guide rod and an adjusting knob to control the assembly stress of the fuel cell, so that the internal stress of the fuel cell is uniform, and the aim of adjusting the local assembly stress in the fuel cell is fulfilled.

The present invention provides an adjustable stress structure for a fuel cell, which includes a first pressure end plate, a first set of springs, a first set of guide rods, a fuel cell, a plurality of first pressure knobs and a plurality of locking members. The fuel cell has a first cell end plate and a second cell end plate. The first pressure end plate is provided with a plurality of first slotted holes. The first group of springs is arranged between the first battery end plate and the first pressure end plate. The first group of guide rods respectively penetrate through the first group of springs and are connected with the first battery end plate and the first pressure end plate. The first pressure knobs are arranged in the first slot holes of the first pressure end plate and above the first group of guide rods. The plurality of locking pieces are used for fixing the first pressure end plate, the first battery end plate and the second battery end plate. The stress of the first group of springs is adjusted by adjusting the first pressure knobs, so that the internal stress of the fuel cell is uniformly distributed

The present invention further provides a method for regulating and controlling stress of an adjustable stress structure for a fuel cell, comprising the following steps: measuring a raw impedance value of the fuel cell; adjusting the pressure knob according to the original impedance value; confirming the impedance value of the fuel cell after the pressure knob is adjusted; and confirming the stress distribution of the fuel cell after the pressure knob is adjusted.

Compared with the existing fuel cell module, the invention has the following advantages:

1. the assembling stress of the fuel cell is controlled by using a plurality of springs with high elastic coefficient, guide rods and adjusting knobs, so that the internal stress of the fuel cell is uniform.

2. By using the adjustable stress structure, the cell end plate can be prevented from being deformed and bent, and the local assembly stress of the fuel cell can be controlled, so as to adjust the local assembly stress in the fuel cell, thereby realizing uniform electrochemical reaction in the fuel cell.

Drawings

Figure 1 is a schematic diagram of a prior art fuel cell module.

Fig. 2 is an exploded view of an adjustable stress structure for a fuel cell according to the present invention.

Fig. 3 is an external perspective view of an adjustable stress structure for a fuel cell according to the present invention.

Fig. 4 is an external perspective view of an adjustable stress structure for a fuel cell according to an embodiment 2 of the present invention.

Fig. 5 is an external perspective view of an adjustable stress structure for a fuel cell according to an embodiment 3 of the present invention.

Fig. 6 is an external perspective view of an adjustable stress structure for a fuel cell according to an embodiment 4 of the present invention.

Fig. 7 is a flow chart of a stress control method for an adjustable stress structure of a fuel cell according to the present invention.

Wherein the reference numerals are:

1: fuel cell module 2: fuel cell

4: upper battery end plate 6: lower battery end plate

8: screw rod

100. 200, 300, 400: adjustable stress structure for fuel cell

10: first pressure end plate 20: first set of springs

30: first set of guide rods 40, 70: fuel cell

50: the plurality of first pressure knobs 52: gasket

60: a plurality of locking pieces 42: first battery end plate

44: second cell end plate 46: multiple perforations

12: first slots 82: a plurality of second slots

80: second pressure end plate 90: second set of springs

96: second set of guide rods 98: a plurality of second pressure knobs

Detailed Description

The invention uses a plurality of springs with high elastic coefficient, a guide rod and an adjusting knob to control the assembly stress of the fuel cell, so that the internal stress of the fuel cell is uniform, the local assembly stress in the fuel cell is adjusted, and the electrochemical reaction in the fuel cell can be uniformly carried out.

Example 1: fig. 2 is an exploded view of an adjustable stress structure for a fuel cell according to the present invention. As shown in fig. 2, the adjustable stress structure 100 for a fuel cell has a first pressure end plate 10, a first set of springs 20, a first set of guide rods 30, a fuel cell 40, a plurality of first pressure knobs 50, and a plurality of locking members 60. The fuel cell 40 is used for converting chemical energy in fuel into electrical energy, and the fuel cell 40 has a first cell end plate 42, a second cell end plate 44 and a plurality of perforations 46, wherein the plurality of perforations 46 are used for enhancing the fixing of the fuel cell 40, and the plurality of perforations 46 are not necessary in the present invention. The first pressure end plate 10 has a plurality of first slots 12. A first set of springs 20 is disposed between the first cell end plate 42 and the first pressure end plate 10. Each of the first set of guide rods 30 extends through the first set of springs 20 and connects the first cell end plate 42 and the first pressure end plate 10. A plurality of first pressure knobs 50 are disposed in the first slots 12 of the first pressure end plate 10 and above the first set of guide rods 30. A gasket 52 is disposed between each first pressure knob 50 and each first slot 12. A plurality of fasteners 60 are used to secure the first pressure end plate 10, the first cell end plate 42 and the second cell end plate 44.

Fig. 3 is an external perspective view of an adjustable stress structure for a fuel cell according to the present invention. As shown in fig. 3, the present invention adjusts the stress of the first set of springs 20 by adjusting the first pressure knob 50, so that the internal stress of the fuel cell 40 is uniformly distributed.

In embodiment 1, a second pressure end plate (not shown) may be further included on the second cell end plate 44 side, and the second pressure end plate is locked by a plurality of locking members.

Example 2: fig. 4 is an external perspective view of an adjustable stress structure for a fuel cell according to an embodiment 2 of the present invention. As shown in fig. 4, the adjustable stress structure 200 for a fuel cell is all the elements of the adjustable stress structure 100 for a fuel cell of embodiment 1, and further includes a second pressure end plate 80, a second set of springs 90, a second set of guide rods 96, and a plurality of second pressure knobs 98. The second pressure end plate 80 has a plurality of second slots 82. A second set of springs 90 is disposed between the second cell end plate 44 and the second pressure end plate 80. Each of the second set of guide rods 96 extends through the second set of springs 90 and connects the second cell end plate 44 and the second pressure end plate 80, respectively. A second plurality of pressure knobs 98 are disposed within the second plurality of slots 82 of the second pressure end plate 80 and above the second plurality of guide rods 96. In embodiment 2, a plurality of fasteners 60 are used to secure the first pressure end plate 10, the second pressure end plate 80, the first cell end plate 42 and the second cell end plate 44. As shown in fig. 4, the present invention adjusts the stresses of the first set of springs 20 and the second set of springs 90 by adjusting the first pressure knob 50 and the second pressure knob 98 so that the internal stresses of the fuel cell 40 are evenly distributed.

Example 3: fig. 5 is an external perspective view of an adjustable stress structure for a fuel cell according to an embodiment 3 of the present invention. As shown in fig. 5, the adjustable stress structure 300 for a fuel cell has a first pressure end plate 10, a first set of springs 20, a first set of guide rods 30, a fuel cell 70, a plurality of first pressure knobs 50, and a plurality of locking members 60. The first pressure end plate 10, the first set of springs 20, the first set of guide rods 30, the plurality of first pressure knobs 50, the plurality of locking members 60, the first cell end plate 42, and the second cell end plate 44 of the adjustable stress structure 300 for a fuel cell are the same as and equivalent to those of embodiment 1. The difference between the adjustable stress structure 300 and the adjustable stress structure 100 for a fuel cell in this embodiment 3 is that a plurality of locking members 60 are located at the outer side of the fuel cell 70 to fix the fuel cell 70.

Example 4: fig. 6 is an external perspective view of an adjustable stress structure for a fuel cell according to an embodiment 4 of the present invention. As shown in fig. 6, the adjustable stress structure 400 for a fuel cell has a fuel cell 70. The difference between the adjustable stress structure 400 and the adjustable stress structure 200 in this embodiment 4 is that a plurality of fasteners are located on the outer side of the fuel cell 70 to fix the fuel cell 70.

Example 5: fig. 7 is a flow chart of a stress control method for an adjustable stress structure of a fuel cell according to the present invention. First, the adjustable stress structure 100, 200, 300, or 400 for a fuel cell is assembled, as shown in step S10. Next, the raw impedance value of the fuel cell 40 is measured as shown in step S20. Then, the pressure knob is adjusted according to the original impedance value, as shown in step S30. Then, the impedance value of the fuel cell after the pressure knob is adjusted is measured, as shown in step S40. Finally, the stress distribution of the fuel cell after adjusting the pressure knob is confirmed, as shown in step S50.

The springs 20, 90 of the present invention are springs of the same or different spring rates. At least one of the first pressure end plate 10 and the second pressure end plate 80 of the present invention has an X-shape, and the shape thereof is not limited thereto, and the material thereof is aluminum alloy, magnesium alloy, titanium alloy, or plastic steel, but is not limited thereto. The fuel cell 40 or the fuel cell 70 of the present invention may be a single fuel cell or a plurality of fuel cells.

The invention relates to a setting and a result of analysis of compressive stress in a cell of an adjustable stress structure for a fuel cell, which are used for analyzing the compressive stress in the actual assembly of the fuel cell.

Setting of the battery internal compressive stress analysis:

1. the effect of the adjustable stress structure of the invention for improving the uniform distribution of the internal stress of the cell is verified through the monitoring feedback of the internal stress of the fuel cell.

2. Since the fuel cell is symmetrical in shape, analysis was undertaken for the 1/4 region, and this 1/4 region was divided into nine-grid cells, with a corresponding pressure sensor placed in each cell to monitor pressure changes.

The results of the internal compressive stress analysis of the battery are shown in the following table:

1. the internal pressure stress of the fuel cell with the adjustable stress structure of the present invention is increased by more than 2 times.

2. The pressure uniformity of the whole fuel cell with the adjustable stress structure of the present invention is improved by more than 30%.