A cylindrical low-voltage nickel-hydrogen battery

Abstract

The present invention discloses a cylindrical low-pressure nickel-hydrogen battery, comprising a shell and a cap. A hydrogen storage material tube is arranged in the center of the shell, the hydrogen storage material tube is wrapped by the battery cell, and the lower end is in contact with the shell. The shell is the negative electrode of the power supply, and the cap is the positive electrode of the power supply. This technology solves the problems of high working hydrogen pressure, large volume and safety of nickel-hydrogen batteries, and at the same time realizes a battery structure that is easy to package, compact, highly thermally conductive, has a long service life, is low in cost and has a simple process.

Description

Technical Field

[0001] The invention relates to a chemical power source, in particular to a cylindrical low-voltage nickel-hydrogen battery. Background Art

[0002] Nickel-hydrogen battery is a kind of battery with nickel hydroxide as the positive electrode and hydrogen storage material as the negative electrode. It has the characteristics of high volume energy density, high mass power ratio, good safety, easy scalability, wide operating temperature range (-50~70℃) and environmental friendliness. It is widely used in strategic industries such as energy-saving and new energy vehicles, wind and solar energy storage. At present, the global total sales of hybrid vehicles using high-power nickel-hydrogen batteries have exceeded 20 million, far exceeding the combined sales of pure electric vehicles and plug-in hybrid vehicles using lithium-ion batteries. Fuel cell vehicles using high-power nickel-hydrogen batteries have also been put on the market and become the focus of future development. At the same time, high-energy-density nickel-hydrogen batteries have begun to emerge in the field of fixed energy storage such as uninterruptible power supply, wind and solar power generation, and smart grids, showing strong competitiveness. However, the existing nickel-hydrogen battery technology still has the disadvantages of short deep discharge cycle life (500~1000 times) and easy failure when shelved in the discharged state. Nickel-hydrogen battery is a kind of battery with nickel hydroxide as the positive electrode and hydrogen as the negative electrode. It has the longest cycle life of all maintenance-free battery systems. The full charge and full discharge cycle life can reach 1500-6000 times. The cycle life can reach 40,000 times when the discharge depth is controlled at 40%. The service life on geosynchronous orbit satellites can reach 15 years. It also has the advantages of overcharge and over-discharge resistance. However, its disadvantages are small volume-to-energy ratio, high working hydrogen pressure (41-83 atmospheres), high self-discharge, high cost, and poor safety performance.

[0003] The present invention aims at the shortcomings of the above-mentioned nickel-hydrogen battery and hydrogen-nickel battery, combines the advantages of both, and proposes a cylindrical low-voltage hydrogen-nickel battery to solve the above-mentioned shortcomings of nickel-hydrogen battery and hydrogen energy battery, which will greatly promote the development of high specific energy and long life hydrogen-nickel battery technology. Summary of the invention

[0004] In view of the above-mentioned prior art, the present invention proposes a cylindrical low-pressure nickel-hydrogen battery, which removes the high-pressure hydrogen storage tank and has a battery structure with small size, low cost and simple process, while achieving the purposes of easy packaging, compactness and high thermal conductivity.

[0005] The present invention adopts the following technical solutions:

[0006] A cylindrical low-voltage nickel-hydrogen battery comprises a shell and a cap. A hydrogen storage material tube is provided in the center of the shell, and the hydrogen storage material tube is wrapped by the battery core. The shell is the negative electrode of the power supply, and the cap is the positive electrode of the power supply.

[0007] Preferably, the hydrogen storage material tube comprises a cylindrical cavity formed by carbon paper, the cavity is filled with hydrogen storage material powder, and the carbon paper is wrapped with a breathable film to block the influence of the electrolyte on the hydrogen storage material powder. It can absorb hydrogen during charging and release hydrogen during discharging, so that the pressure in the shell is controlled within the range of less than 1.0MPa, the pressure value is significantly reduced, and the use safety is higher.

[0008] Preferably, the hydrogen storage material tube comprises a metal tube, the metal tube is filled with hydrogen storage material powder, the upper end opening is provided with a vent plug, the vent plug comprises a gasket, and the gasket is provided with carbon paper and a vent film in sequence. The metal tube can conduct heat and make the structure more stable.

[0009] Preferably, the breathable membrane is made of a waterproof, oxygen-proof, and hydrogen-permeable material, through which hydrogen can enter but impurities such as oxygen and water cannot.

[0010] Preferably, the battery core includes a diaphragm, the inner side of the diaphragm is a negative electrode catalyst layer, the outer side is a positive electrode sheet, the three are wound in sequence, and the negative electrode catalyst layer is in contact with the shell. The battery core is in contact with the electrolyte, and hydrogen evolution / desorption electrochemical reactions occur during charging / discharging.

[0011] Preferably, when the battery cell is wound, the hydrogen storage material tube can be used as a winding needle, and the battery cell is wound into shape by the positive electrode sheet, the diaphragm, and the negative electrode catalyst layer, thereby improving production efficiency. At the same time, the hydrogen storage material tube is used as a winding needle to increase the diameter of the winding needle, so that the electrode sheet is less deformed and subjected to less force, and is not easy to break during the production process, resulting in short circuit and increased scrap rate. It is also not easy to cause the electrode sheet to crack or break during the subsequent use of the battery due to factors such as the expansion of the electrode sheet, resulting in battery failure, or even short circuit and other safety hazards.

[0012] Preferably, the positive electrode sheet is connected to the cap, and the cap is arranged on the shell, and the two are insulated. The cap and the shell are insulated by using a glue seal to avoid short circuit and prevent hydrogen leakage.

[0013] Preferably, a hydrogen redox catalyst is coated on the negative electrode catalyst layer to make the chemical reaction more efficient.

[0014] The beneficial effects of the present invention are:

[0015] 1. The advantage of cylindrical design is that it can utilize the mature process equipment, and its production efficiency is higher than that of lamination technology;

[0016] 2. The battery center uses hydrogen storage material tubes to wind the battery cells, which can reduce the problems of cracks, powder loss, micro short circuits, etc. that are easy to occur in the pole pieces when the existing needle winding battery cells are wound, and improve the product qualification rate;

[0017] 3. The hydrogen storage material is placed in the hydrogen storage material tube at the center of the battery, isolated from the electrolyte, which can eliminate the corrosion of the electrolyte on the hydrogen storage material, greatly extend the cycle life and service life of the battery, and solve the problem of short cycle life of nickel-hydrogen batteries;

[0018] 4. The hydrogen storage material is placed in the hydrogen storage material tube at the center of the battery, isolated from the electrolyte, which can eliminate the corrosion of the electrolyte on the hydrogen storage material. This can eliminate the problem of metal cobalt in the negative electrode hydrogen storage alloy of the existing nickel-hydrogen battery and reduce the battery cost;

[0019] 5. The center of the low-voltage nickel-hydrogen battery uses a hydrogen storage material tube in contact with the battery shell, which can quickly conduct heat from the inside of the battery, improve battery charging efficiency, and inhibit oxygen evolution at the positive electrode;

[0020] 6. The hydrogen storage material is placed in the hydrogen storage material tube at the center of the battery, isolated from the electrolyte, which can eliminate the corrosion of the electrolyte on the hydrogen storage material. A higher capacity hydrogen storage material can be used to improve the battery energy density and solve the existing problems of low energy density and specific energy of nickel-hydrogen batteries;

[0021] 7. Using hydrogen storage materials to store hydrogen, the hydrogen storage density is more than 1,000 times higher than that of gaseous hydrogen, which can solve the problem of existing nickel-hydrogen batteries being too large and having low volume energy density;

[0022] 8. Hydrogen is stored in hydrogen storage materials, and the working hydrogen pressure of the battery is less than 1.0MPa, which is significantly lower than the working hydrogen pressure of existing nickel-hydrogen batteries, making it safer to use and reducing the self-discharge of the battery;

[0023] 9. As hydrogen storage materials have a hydrogen absorption and release platform, using hydrogen storage materials to store hydrogen can eliminate the problem of the existing nickel-hydrogen battery's working voltage tilt, and the battery's charge and discharge characteristics are better, and the discharge voltage is more stable;

[0024] 10. Using hydrogen storage materials to store hydrogen, the volume is greatly reduced compared to existing nickel-hydrogen batteries, which reduces the cost of batteries;

[0025] 11. The use of cylindrical low-voltage nickel-hydrogen batteries can solve the existing semi-circular end and stacking production process of nickel-hydrogen batteries, and solve the problem of low production efficiency of existing nickel-hydrogen batteries;

[0026] 12. The breathable membrane is made of waterproof, oxygen-proof and hydrogen-permeable material to prevent the electrolyte from contacting the hydrogen storage material powder and increase the service life. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings of the embodiments will be briefly introduced below. Obviously, the drawings in the following description only relate to some embodiments of the present invention, but are not intended to limit the present invention.

[0028] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0029] Figure 2 It is a structural schematic diagram of another embodiment of the hydrogen storage material tube of the present invention;

[0030] Figure 3 It is a schematic diagram of the structure of the vent plug of the present invention;

[0031] As shown in the figure

[0032] 1—breathable membrane, 2—carbon paper, 3—hydrogen storage material powder, 4—negative electrode catalyst layer, 5—diaphragm, 6—positive electrode sheet, 7—shell, 8—cap, 9—metal tube, 10—gasket. DETAILED DESCRIPTION

[0033] In order to make the purpose, technical solution and advantages of the embodiment of the present invention clearer, the technical solution of the embodiment of the present invention will be clearly and completely described below in conjunction with the drawings of the embodiment of the present invention. Obviously, the described embodiment is a part of the embodiment of the present invention, not all of the embodiments. Based on the described embodiment of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0034] The present invention is further described below in conjunction with the accompanying drawings and embodiments.

[0035] like Figure 1 A cylindrical low-voltage nickel-hydrogen battery is shown, comprising a shell 7 and a cap 8. A hydrogen storage material tube is provided in the center of the shell. The hydrogen storage material tube is wrapped by the battery cell and the lower end is in contact with the shell 7. The shell 7 is the negative pole of the power supply and the cap 8 is the positive pole of the power supply.

[0036] As a technical optimization solution of the present invention, the hydrogen storage material tube includes a cylindrical cavity formed by carbon paper 2, the cavity is filled with hydrogen storage material powder 3, the carbon paper 2 is wrapped with a breathable membrane 1, the breathable membrane 1 and the carbon paper 2 can prevent the electrolyte from penetrating, and provide a diffusion channel for hydrogen, which can achieve isolation of the electrolyte and avoid the influence of the electrolyte on the hydrogen storage material powder 3. The hydrogen storage material powder 3 can absorb hydrogen during charging and release hydrogen during discharging, so that the pressure in the shell is controlled within a range of less than 1.0MPa, the pressure value is significantly reduced, and the use safety is higher.

[0037] As a technical optimization solution of the present invention, the hydrogen storage material tube includes a metal tube 9, the metal tube 9 is filled with hydrogen storage material powder 3, the upper end opening is provided with a gasket, the gasket includes a gasket 10, and the gasket 10 is sequentially provided with carbon paper 2 and a gas permeable membrane 1. The metal tube 9 can conduct heat and make the structure more stable.

[0038] As a technical optimization solution of the present invention, the breathable membrane 1 is made of a waterproof, oxygen-proof and hydrogen-permeable material to block the electrolyte.

[0039] As a technical optimization solution of the present invention, the battery cell includes a diaphragm 5, the inner side of the diaphragm 5 is a negative electrode catalyst layer 4, the outer side is a positive electrode sheet 6, the three are wound in sequence, and the negative electrode catalyst layer 4 is in contact with the shell 7. The battery cell is in contact with the electrolyte, and hydrogen evolution / desorption electrochemical reactions occur during charging / discharging.

[0040] Positive electrode 6 charging (discharging is the opposite): Ni(OH)2+OH - →NiOOH+H2O+e -

[0041] Negative electrode catalyst layer 4 charging (discharging is the opposite): H2O+e - →1 / 2H2+OH -

[0042] As a technical optimization solution of the present invention, when the battery cell is wound, the hydrogen storage material tube can be used as a winding needle, and the battery cell is wound into shape by the positive electrode sheet 6, the diaphragm 5, and the negative electrode catalyst layer 4, thereby improving production efficiency. At the same time, the hydrogen storage material tube is used as a winding needle to increase the diameter of the winding needle, so that the pole piece is less deformed and subjected to less force, and is not easy to break during the production process, resulting in short circuit and increased scrap rate. It is also not easy to cause the pole piece to crack or break during the subsequent use of the battery due to factors such as pole piece expansion, resulting in battery failure, or even short circuit and other safety hazards.

[0043] As a technical optimization solution of the present invention, the positive electrode sheet 6 is connected to the cap 8, and the cap 8 is arranged on the shell 7, and the two are insulated. A glue seal is used to prevent the cap 8 from contacting the shell 7, avoiding short circuit and preventing hydrogen leakage.

[0044] As a technical optimization solution of the present invention, a hydrogen redox catalyst is coated on the negative electrode catalyst layer 4 to make the chemical reaction more efficient.

[0045] The first manufacturing method of the present invention is to first wrap the hydrogen storage material powder 3 with carbon paper 2 and breathable membrane 1 to make a hydrogen storage material tube. The second step is to use the hydrogen storage material tube as a winding needle, and wind the battery cell formed by the positive electrode sheet 6, the diaphragm 5, and the negative electrode catalyst layer 4 on the winding needle hydrogen storage material tube, so as to improve the production efficiency and increase the diameter of the winding needle. In this way, the electrode sheet is less deformed and less stressed, and it is not easy to break during the production process, resulting in short circuit and increased scrap rate. It is also not easy to cause the electrode sheet to crack and break during the subsequent use of the battery due to factors such as electrode sheet expansion, resulting in battery failure, and even short circuit and other safety hazards. The third step is to place the hydrogen storage material tube wrapped by the battery cell in the center of the shell 7 to make the contact surface with hydrogen larger, the speed faster, and the structure compact, easy to operate, and the process simple. The fourth step is to inject the electrolyte into the shell 7. The fifth step is to connect the positive electrode sheet 6 to the cap 8 through a wire, and avoid contact with the shell 7 through glue sealing to prevent hydrogen leakage. Finally, the entire shell 7 is sealed and the battery is manufactured.

[0046] The second manufacturing method of the present invention is as follows: the first step is to select a metal tube 9 of a certain size, fill the metal tube 9 with hydrogen storage material powder 3, and then cover it with a gasket 10, carbon paper 2, and a gas-permeable plug made of a gasket 10, carbon paper 2, and a gas-permeable membrane 1 to complete the hydrogen storage material tube. The second step is to use the hydrogen storage material tube as a winding needle, and wind the battery cell formed by the positive electrode sheet 6, the diaphragm 5, and the negative electrode catalyst layer 4 on the winding needle hydrogen storage material tube, thereby improving production efficiency and increasing the diameter of the winding needle. This makes the electrode sheet deform less and bear less force, and is not easy to break during the production process, resulting in short circuit and increased scrap rate. It is also not easy to cause the electrode sheet to crack or break during the subsequent use of the battery due to factors such as electrode sheet expansion, resulting in battery failure, and even short circuit and other safety hazards. The third step is to fix the hydrogen storage material tube wrapped by the battery cell to the center position of the lower surface inside the shell 7, and the metal tube 9 can conduct the heat inside the battery to increase stability. The fourth step is to inject the electrolyte into the shell 7. The fifth step is to connect the positive electrode sheet 6 to the cap 8 through a wire, and avoid contact with the shell 7 through a glue seal to prevent hydrogen leakage. Finally, the entire housing 7 is sealed and the battery is completed.

[0047] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any form. Although the present invention has been disclosed as a preferred embodiment as above, it is not used to limit the present invention. Any technician familiar with this profession can make some changes or modifications to equivalent embodiments of equivalent changes using the technical contents disclosed above without departing from the scope of the technical solution of the present invention. However, any simple modification, equivalent change and modification made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention still falls within the technical scope of the present invention.

Claims

1. A cylindrical low-voltage nickel-hydrogen battery, characterized in that: It comprises a shell (7) and a cap (8), wherein a hydrogen storage material tube is provided in the center of the shell (7), the hydrogen storage material tube is wrapped by the battery core, the shell (7) is the negative electrode of the power supply, and the cap (8) is the positive electrode of the power supply; The battery cell comprises a diaphragm (5), the inner side of the diaphragm (5) is a negative electrode catalyst layer (4), and the outer side is a positive electrode sheet (6), the three being wound in sequence, and the negative electrode catalyst layer (4) is in contact with the shell (7); The hydrogen storage material tube comprises a cylindrical cavity formed by carbon paper (2), the cavity is filled with hydrogen storage material powder (3), and the carbon paper (2) is wrapped with a breathable membrane (1); or, The hydrogen storage material tube comprises a metal tube (9), the metal tube (9) is filled with hydrogen storage material powder (3), the upper opening is provided with a gas permeable plug, the gas permeable plug comprises a gasket (10), and the gasket (10) is provided with carbon paper (2) and a gas permeable membrane (1) in sequence; When the battery core is wound, the hydrogen storage material tube is used as the winding tube.

2. A cylindrical low-voltage nickel-hydrogen battery according to claim 1, characterized in that: The breathable membrane (1) is made of a waterproof, oxygen-proof and hydrogen-permeable material.

3. A cylindrical low-voltage nickel-hydrogen battery according to claim 1, characterized in that: The positive electrode sheet (6) is connected to a cap (8), and the cap (8) is arranged on the housing (7), and the two are insulated.

4. A cylindrical low-voltage nickel-hydrogen battery according to claim 1, characterized in that: The negative electrode catalyst layer (4) is coated with a hydrogen redox catalyst.

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