Zinc-air battery and preparation method thereof

Abstract

The present application provides a zinc-air battery and a preparation method thereof, relating to the technical field of batteries. The zinc-air battery may include: a negative electrode cover, a negative electrode reactant, a separator, a positive electrode sheet, and a positive electrode case; the negative electrode reactant is disposed within the negative electrode cover; the opening of the positive electrode case faces the opening of the negative electrode cover, and the positive electrode case is buckled on the negative electrode cover; the positive electrode sheet and the separator are disposed within the positive electrode case, the separator is located on the side facing the opening within the positive electrode case, and the separator is located between the positive electrode sheet and the negative electrode reactant; one side of the positive electrode sheet is in contact with the separator, and the other side of the positive electrode sheet is in contact with the bottom of the positive electrode case; the difference between the diameter of the bottom of the positive electrode case and the diameter of the positive electrode sheet is within a preset size range, and the maximum value of the preset size range is less than or equal to a first preset size value. Since the maximum value of the preset size range is less than or equal to the first preset size value, the positive electrode case and the positive electrode sheet can be fully contacted, improving the resistance stability of the zinc-air battery and the stability during discharge of the zinc-air battery.

Description

Technical Field

[0001] The present invention relates to the technical field of batteries, and more particularly, to a zinc-air battery and a method for preparing the zinc-air battery. Background Art

[0002] The zinc-air battery is a primary battery. It has the characteristic of high energy density and is widely used in portable devices, such as Bluetooth headsets, hearing aids, etc., which can supply power to the portable devices.

[0003] In the related art, a zinc-air battery is formed by performing related process treatments on the positive electrode sheet, the positive electrode case, and other components. Among them, the size of the positive electrode sheet is smaller than the size of the positive electrode case.

[0004] However, in the related art, when the sizes of the positive electrode sheet and the positive electrode case of the zinc-air battery are not reasonably designed, problems such as a relatively large resistance or unstable resistance of the zinc-air battery and unstable discharge of the zinc-air battery are likely to occur. Summary of the Invention

[0005] The purpose of the present invention is to provide a zinc-air battery and a method for preparing the zinc-air battery to solve the problems in the related art that when the sizes of the positive electrode sheet and the positive electrode case of the zinc-air battery are not reasonably designed, the resistance of the zinc-air battery is relatively large and the stability of the discharge of the zinc-air battery is reduced.

[0006] To achieve the above object, the technical solutions adopted in the embodiments of the present invention are as follows:

[0007] In a first aspect, an embodiment of the present invention provides a zinc-air battery, including a negative electrode cover, a negative electrode reactant, a separator, a positive electrode sheet, and a positive electrode case; the negative electrode reactant is disposed in the negative electrode cover; the opening of the positive electrode case faces the opening of the negative electrode cover and is buckled on the negative electrode cover;

[0008] The positive electrode sheet and the separator are disposed in the positive electrode case. The separator is located on the side of the positive electrode case facing the opening, and the separator is located between the positive electrode sheet and the negative electrode reactant; one side of the positive electrode sheet is in contact with the separator, and the other side of the positive electrode sheet is in contact with the bottom of the positive electrode case;

[0009] The difference between the diameter of the bottom of the positive electrode case and the diameter of the positive electrode sheet is within a preset size range, and the maximum value of the preset size range is less than or equal to a first preset size value.

[0010] Further, the minimum value of the preset size range is greater than or equal to a second preset size value.

[0011] Further, the first preset dimension value is 0.08 mm, and the second preset dimension is 0.01 mm.

[0012] Further, the positive electrode sheet includes: a current collector network, a catalyst layer, and a waterproof and breathable layer; the current collector network is uniformly distributed in the catalyst layer; one side of the catalyst layer is in contact with the waterproof and breathable layer, and the other side of the waterproof and breathable layer is in contact with the bottom of the positive electrode case.

[0013] Further, the bottom of the positive electrode case has a groove area, and the other side of the positive electrode sheet is in contact with the outer position between the groove area at the bottom of the positive electrode case.

[0014] Further, the zinc-air battery includes: diffusion paper; the diffusion paper is provided in the groove area.

[0015] Further, at least one air hole is provided at the bottom of the groove area.

[0016] Further, the diameter of each air hole is any dimension in the range of 0.20 mm - 0.45 mm.

[0017] Further, a sealing ring is filled between the inner wall of the positive electrode case and the outer wall of the negative electrode cover.

[0018] In a second aspect, an embodiment of the present application further provides a method for manufacturing a zinc-air battery, including:

[0019] Performing punching on a positive electrode coil to obtain a positive electrode sheet;

[0020] Performing stamping on a housing plate to obtain a positive electrode case;

[0021] Performing encapsulation on a pre-obtained negative electrode cover, a negative electrode reactant, a separator, the positive electrode sheet, and the positive electrode case to obtain the zinc-air battery according to any one of the first aspects above.

[0022] The beneficial effects of the present application are as follows: An embodiment of the present invention provides a zinc-air battery, which may include: a negative electrode cover, a negative electrode reactant, a separator, a positive electrode sheet, and a positive electrode case; the negative electrode reactant is disposed inside the negative electrode cover; the opening of the positive electrode case faces the opening of the negative electrode cover and is buckled on the negative electrode cover; the positive electrode sheet and the separator are disposed inside the positive electrode case, the separator is located on the side of the positive electrode case facing the opening, and the separator is located between the positive electrode sheet and the negative electrode reactant; one side of the positive electrode sheet is in contact with the separator, and the other side of the positive electrode sheet is in contact with the bottom of the positive electrode case; the difference between the diameter of the bottom of the positive electrode case and the diameter of the positive electrode sheet is within a preset size range, and the maximum value of the preset size range is less than or equal to a first preset size value. By setting the difference between the diameter of the bottom of the positive electrode case and the diameter of the positive electrode sheet within a preset size range, where the maximum value of the preset size range is less than or equal to the first preset size value, the positive electrode case and the positive electrode sheet can be fully contacted, avoiding the problem of excessive resistance, improving the resistance of the zinc-air battery, and the stability during the discharge of the zinc-air battery. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention, and therefore should not be regarded as limiting the scope. For those of ordinary skill in the art, other related drawings can also be obtained based on these drawings without creative efforts.

[0024] Figure 1 is a schematic longitudinal cross-sectional structure diagram of the zinc-air battery provided by the embodiment of the present invention;

[0025] Figure 2 is a schematic longitudinal cross-sectional structure diagram of the zinc-air battery provided by the embodiment of the present invention;

[0026] Figure 3 is a schematic longitudinal cross-sectional structure diagram of the zinc-air battery provided by the embodiment of the present invention;

[0027] Figure 4 is a schematic flowchart of a preparation method of a zinc-air battery provided by the embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0028] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention.

[0029] The zinc-air battery provided by the present application is illustrated by the following multiple examples.

[0030] Figure 1The following is a schematic structural diagram of the zinc-air battery provided by the embodiments of the present invention. As Figure 1 shown, the zinc-air battery may include: a negative electrode cover 101, a negative electrode reactant 102, a separator 103, a positive electrode sheet 104, and a positive electrode case 105. The negative electrode reactant 102 is disposed within the negative electrode cover 101; the opening of the positive electrode case 105 faces the opening of the negative electrode cover 101 and is buckled on the negative electrode cover 101.

[0031] Among them, the positive electrode sheet 104 and the separator 103 are disposed within the positive electrode case 105. The separator 103 is located on the side of the positive electrode case 105 facing the opening, and the separator 103 is located between the positive electrode sheet 104 and the negative electrode reactant 102; one side of the positive electrode sheet 104 is in contact with the separator 103, and the other side of the positive electrode sheet 104 is in contact with the bottom of the positive electrode case 105.

[0032] Moreover, the difference between the bottom diameter of the positive electrode case 105 and the diameter of the positive electrode sheet 104 can be set within a preset size range, and the maximum value of the preset size range is less than or equal to the first preset size value.

[0033] In the embodiments of the present invention, the outer diameter of the negative electrode cover 101 can be smaller than the inner diameter of the positive electrode case 105, and the diameter of the negative electrode cover 101 near the bottom of the positive electrode case 105 is larger than the diameter of the negative electrode cover 101 away from the bottom of the positive electrode case 105. The bottom diameter of the above positive electrode case 105 can be the bottom inner diameter of the positive electrode case 105.

[0034] It should be noted that the negative electrode reactant 102 can be zinc paste, and the zinc paste can include zinc powder and an electrolyte, and the electrolyte can be a potassium hydroxide solution. The positive electrode case 105 can be made of an anti-corrosion material. For example, the anti-corrosion material can be a double-sided nickel-plated stainless steel material.

[0035] In addition, the diameter of the separator 103 can be the same as the inner diameter of the positive electrode case 105. The separator 103 can be used to isolate the positive electrode and the negative electrode. The material of the separator 103 can be a non-woven fabric and microporous polypropylene composite separator. Of course, it can also be other materials that can isolate the positive electrode and the negative electrode. The embodiments of the present invention do not specifically limit this.

[0036] In the embodiments of the present invention, the zinc powder in the negative electrode reactant 102 can lose electrons, and oxygen can obtain electrons and be oxidized under the catalysis of manganese dioxide in the positive electrode sheet 104, thereby enabling the discharge of the zinc-air battery.

[0037] In summary, an embodiment of the present invention provides a zinc-air battery, which may include: a negative electrode cover, a negative electrode reactant, a separator, a positive electrode sheet, and a positive electrode case; the negative electrode reactant is disposed within the negative electrode cover; the opening of the positive electrode case faces the opening of the negative electrode cover and is fastened to the negative electrode cover; the positive electrode sheet and the separator are disposed within the positive electrode case, the separator is located on the side of the positive electrode case facing the opening, and the separator is located between the positive electrode sheet and the negative electrode reactant; one side of the positive electrode sheet contacts the separator, and the other side of the positive electrode sheet contacts the bottom of the positive electrode case; the difference between the diameter of the bottom of the positive electrode case and the diameter of the positive electrode sheet is within a preset size range, and the maximum value of the preset size range is less than or equal to a first preset size value. Making the difference between the diameter of the bottom of the positive electrode case and the diameter of the positive electrode sheet within a preset size range, where the maximum value of the preset size range is less than or equal to a first preset size value, enables the positive electrode case and the positive electrode sheet to be in full contact, avoiding the problem of excessive resistance and also improving the resistance of the zinc-air battery and the stability during discharge of the zinc-air battery.

[0038] Optionally, the minimum value of the preset size range is greater than or equal to a second preset size value.

[0039] Wherein, the maximum value of the above-mentioned preset size range is less than or equal to a first preset size value, and the minimum value is greater than or equal to a second preset size value.

[0040] It should be noted that when the maximum value of the above-mentioned preset size range is less than or equal to a first preset size value, it can ensure the full contact between the positive electrode sheet 104 and the positive electrode case 105, improving the stability of the resistance of the zinc-air battery and the stability of the discharge of the zinc-air battery.

[0041] In addition, when the minimum value of the above-mentioned preset size range is greater than or equal to a second preset size value, it can avoid the problem that the positive electrode sheet 104 is prone to deformation, the discharge is unstable after long-term storage, and the discharge capacity is reduced when the size of the positive electrode sheet 104 is too close to the size of the positive electrode case 105.

[0042] Optionally, the first preset size value is 0.08 millimeters (mm), and the second preset size is 0.01 mm.

[0043] In some embodiments, the diameter of the bottom of the positive electrode case 105 may be represented by a, and the diameter of the positive electrode sheet 104 may be represented by b. Then, the difference between the diameter of the bottom of the positive electrode case 105 and the diameter of the positive electrode sheet 104 may be represented by a - b, and 0.01 mm ≤ a - b ≤ 0.08 mm.

[0044] It should be noted that the diameter of the positive electrode plate 104 can range from 5 mm to 12 mm, and the inner diameter of the bottom of the positive electrode case 105 can also range from 5 mm to 12 mm. For example, if the diameter of the positive electrode plate 104 is 6 mm and the inner diameter of the bottom of the positive electrode case 105 is 6.03 mm, then the difference between the inner diameter of the bottom of the positive electrode case 105 and the diameter of the positive electrode plate 104 can be 0.03 mm.

[0045] Optionally, Figure 2 is a schematic longitudinal sectional structure diagram of the zinc-air battery provided by the embodiment of the present invention. As Figure 2 shown, the positive electrode plate 104 includes: a current collector net 1041, a catalyst layer 1042, and a waterproof and breathable layer 1043; the current collector net 1041 is uniformly distributed in the catalyst layer 1042.

[0046] Among them, one side of the catalyst layer 1042 is in contact with the waterproof and breathable layer 1043, and the other side of the waterproof and breathable layer 1043 is in contact with the bottom of the positive electrode case 105. The positive electrode plate 104 can be a round plate with a certain thickness. The thickness of the positive electrode plate 104 can be between 0.4 mm and 0.5 mm, and the positive electrode plate 104 can be formed by punching a positive electrode coil material with a punching machine.

[0047] In the embodiment of the present invention, the main function of the current collector net 1041 is to conduct electrons and endow the positive electrode plate 104 with a certain processing strength for the processing, punching, and assembly of the positive electrode plate 104. The current collector net 1041 can be cylindrical, and the catalyst layer 1042 can also be a round plate with a certain thickness. The length direction of the current collector net 1041 can be parallel to the diameter direction of the catalyst layer 1042.

[0048] Among them, when the zinc-air battery is a button-type alkaline zinc-air battery, the current collector net 1041 can be made of a material with good corrosion resistance and electrical conductivity, such as a mesh nickel-plated steel net, a silver-plated steel net, a nickel net, etc. The current collector net 1041 can be a woven nickel-plated steel net with a thickness of 0.25 mm and a mesh size of 30 - 40 meshes.

[0049] In addition, the waterproof and breathable membrane is a PTFE (Poly tetra fluoroethylene) membrane with a density of 1.1 g / cm³ - 1.6 g / cm³ and an air permeability of 1000 - 3000 s / in²·100 cc·1.22 kPa. This can prevent the electrolyte from leaking through the PTFE membrane and ensure sufficient air intake for the reaction of the zinc-air battery.

[0050] Optionally, as Figure 2 shown, the bottom of the positive electrode case 105 has a groove area 106, and the other side of the positive electrode plate 104 is in contact with the position outside the groove area 106 at the bottom of the positive electrode case 105.

[0051] Among them, in the longitudinal sectional view of the zinc-air battery, the trapezoidal area enclosed by the waterproof and breathable layer 1043 and the bottom of the positive electrode case 105 is the groove area 106. The groove area 106 can be frustum-shaped, with a larger diameter on the side close to the waterproof and breathable membrane and a smaller diameter on the side far from the waterproof and breathable membrane. Of course, the groove area 106 can also be other shapes, and the embodiments of the present invention do not specifically limit this.

[0052] Optionally, Figure 3 This is a schematic diagram of the longitudinal sectional structure of the zinc-air battery provided by the embodiments of the present invention. As Figure 3 shown, the zinc-air battery can further include: a diffusion paper 107, and the diffusion paper 107 is provided in the groove area 106.

[0053] Among them, the shape of the diffusion paper 107 can be circular, and the size of the diffusion paper 107 can be smaller than the size of the groove area 106.

[0054] Optionally, at least one air hole 108 can be provided at the bottom of the groove area 106.

[0055] Among them, air can pass through the air hole 108 to reach the catalyst layer 1042. Oxygen in the air is oxidized by obtaining electrons under the catalysis of manganese dioxide at the catalyst layer 1042. When the diffusion paper is provided, the air entering from the air hole 108 can be more evenly distributed.

[0056] It should be noted that the number of the air holes 108 can be a preset number. The preset number can be 2, or 3, or 4. The embodiments of the present invention do not specifically limit this.

[0057] In addition, at least one air hole 108 can be evenly distributed or unevenly distributed. The embodiments of the present invention do not specifically limit this.

[0058] Optionally, the diameter of the air hole 108 can be any size in the range of 0.20 mm - 0.45 mm.

[0059] For example, the diameter of the air hole 108 can be 0.30 mm, 0.41 mm, etc.

[0060] Optionally, as Figure 3 shown, a sealing ring 109 is filled between the inner wall of the positive electrode case 105 and the outer wall of the negative electrode cover 101.

[0061] It should be noted that the sealing ring 109 can be made of a material with good compression performance. For example, the material can be a nylon material with good compression performance.

[0062] Figure 4 This is a schematic flow chart of a preparation method of a zinc-air battery provided by the embodiments of the present invention. AsFigure 4 As shown, the method may include:

[0063] S101. Punch the positive electrode coil material to obtain positive electrode sheets.

[0064] In an embodiment of the present invention, a punching machine may be controlled to punch the positive electrode coil material according to a preset first diameter to obtain positive electrode sheets. Wherein, the diameter of the positive electrode sheet is the first diameter.

[0065] Optionally, before S101, the method may further include: preparing the positive electrode coil material.

[0066] In some embodiments, activated carbon, manganese dioxide, graphite, and PTFE powder may be dry-mixed and stirred in a high-speed mixer for 2 hours to obtain a catalyst powder, and then the catalyst powder is roll-pressed into a catalyst layer. Then, the catalyst layer and the current collector net are roll-pressed, and the waterproof and breathable layer, the catalyst layer, and the current collector net are integrally roll-pressed to obtain the positive electrode coil material.

[0067] It should be noted that the current collector net may be evenly distributed in the catalyst layer, and the waterproof and breathable layer may be disposed on one side of the catalyst layer.

[0068] S102. Stamp the housing plate material to obtain a positive electrode housing.

[0069] In a possible embodiment, a stamping machine may be controlled to stamp the housing plate material multiple times to obtain a positive electrode housing. During the last stamping, at least one air hole is stamped at the bottom of the positive electrode housing. The inner diameter of the bottom of the positive electrode housing may be the second diameter.

[0070] S103. Package the pre-obtained negative electrode cap, negative electrode reactant, separator, the positive electrode sheet, and the positive electrode housing to obtain a zinc-air battery.

[0071] Wherein, the zinc-air battery may be Figures 1-3 the zinc-air battery shown in any one of

[0072] In some embodiments, the pre-obtained negative electrode cap, negative electrode reactant, separator, the positive electrode sheet, and the positive electrode housing may be assembled. Of course, the assembled components may further include: diffusion paper, sealing rings, etc. After the assembly is completed, a sealing operation may be performed, and then a zinc-air battery may be obtained.

[0073] It should be noted that for the zinc-air battery after the sealing operation, the outer diameter of the positive electrode housing will shrink to a certain extent to ensure the sealing performance of the battery. After sealing, the sealing ring of the battery will tightly press the edge position of the positive electrode sheet to ensure stable contact between the positive electrode sheet and the bottom of the positive electrode housing.

[0074] In the embodiments of the present invention, experiments were conducted on the sealed zinc-air batteries. The types of zinc-air batteries for the experiments can be 5. The inner diameter of the bottom of the positive electrode case after sealing for each type of zinc-air battery can be 7.50 mm, and the diameters of the positive electrode plates can be 7.40 mm, 7.42 mm, 7.44 mm, 7.46 mm, 7.48 mm, and 7.50 mm respectively. The number of each type of zinc-air battery can be 20. Among them, the discharge procedure adopted can be the heavy-duty pulse discharge in IEC 60086-2:2011 (International Standard). After storing the above batteries at 45 degrees Celsius for one month, the experimental data of various types of batteries are shown in Table 1.

[0075] Table 1

[0076]

[0077] As shown in Table 1, a can be the inner diameter of the bottom of the positive electrode case after sealing, b can be the diameter of the positive electrode plate, and a - b can be the difference between the inner diameter of the bottom of the positive electrode case after sealing and the diameter of the positive electrode plate. When the difference is within the range of 0.01 mm to 0.08 mm, there is no bending of the positive electrode plate of the sealed zinc-air battery, and the contact between the positive electrode plate and the positive electrode case is good, the resistance value is stable, and the IEC pulse discharge capacity is also stable.

[0078] When the difference is 0.10 mm, the difference is relatively large, and there will be a problem of poor contact between the positive electrode plate and the positive electrode case. The resistance range is between 3.1 Ω and 12.0 Ω, the resistance value is unstable, and the IEC pulse discharge capacity is between 0 mAh and 150 mAh, and the discharge capacity is unstable.

[0079] When the difference is 0.00 mm, that is, there is no difference, there will be an excessive contact between the positive electrode plate and the positive electrode case, resulting in the problem of deformation of the positive electrode plate. The IEC pulse discharge capacity is between 76 mAh and 150 mAh, and the discharge capacity is unstable.

[0080] It can be seen that in the embodiments of the present invention, the difference between the bottom diameter of the positive electrode case and the diameter of the positive electrode plate is within a preset size range, and the difference is between 0.01 mm ≤ a - b ≤ 0.08 mm, which can ensure the sufficient contact between the positive electrode plate and the positive electrode case, improve the stability of the resistance of the zinc-air battery, and the stability of the discharge of the zinc-air battery, and can also avoid the problem that the positive electrode plate is prone to deformation when the size of the positive electrode plate is too close to the size of the positive electrode case, the discharge is unstable after long-term storage, and the discharge capacity is reduced.

[0081] The above is only the specific implementation manner of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present application can easily think of changes or substitutions, which should all be covered within the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A zinc-air battery, characterized in that, Comprising: A negative electrode cap, a negative electrode reactant, a separator, a positive electrode sheet, and a positive electrode case; the negative electrode reactant is disposed within the negative electrode cap; the opening of the positive electrode case faces the opening of the negative electrode cap and is snapped onto the negative electrode cap; The positive electrode sheet and the separator are disposed within the positive electrode case, the separator is located on one side of the positive electrode case facing the opening, and, the separator is located between the positive electrode sheet and the negative electrode reactant; one side of the positive electrode sheet is in contact with the separator, and the other side of the positive electrode sheet is in contact with the bottom of the positive electrode case; The difference between the diameter of the bottom of the positive electrode case and the diameter of the positive electrode sheet is within a preset dimension range, and the maximum value of the preset dimension range is less than or equal to a first preset dimension value; The minimum value of the preset dimension range is greater than or equal to a second preset dimension value; The first preset dimension value is 0.08 mm, and the second preset dimension is 0.01 mm; The diameter of the separator is the same as the diameter of the bottom of the positive electrode case; The positive electrode sheet includes: a current collector network, a catalyst layer, and a waterproof and breathable layer; the current collector network is uniformly distributed within the catalyst layer; the catalyst layer is in contact with one side of the waterproof and breathable layer, and the other side of the waterproof and breathable layer is in contact with the bottom of the positive electrode case; wherein, the current collector network is cylindrical, the catalyst layer is a circular sheet with a thickness, and the length direction of the current collector network is parallel to the diameter direction of the catalyst layer; A sealing ring is filled between the inner wall of the positive electrode case and the outer wall of the negative electrode cap, and the sealing ring is made of nylon material with compression performance.

2. The zinc-air battery according to claim 1, wherein The bottom of the positive electrode case has a groove area, and the other side of the positive electrode sheet is in contact with the position outside the groove area at the bottom of the positive electrode case.

3. The zinc-air battery according to claim 2, wherein, The zinc-air battery includes: a diffusion paper; the diffusion paper is disposed within the groove area.

4. The zinc-air battery according to claim 2, wherein, At least one air hole is provided at the bottom of the groove area.

5. The zinc-air battery according to claim 4, characterized in that, The diameter of each air hole is any dimension within 0.20 mm - 0.45 mm.

6. A preparation method of a zinc-air battery, characterized in that, Comprising: Performing punching on a positive electrode coil to obtain a positive electrode sheet; Performing stamping on a housing plate to obtain a positive electrode case; Encapsulating the pre-obtained negative electrode cap, negative electrode reactant, separator, the positive electrode sheet, and the positive electrode case to obtain the zinc-air battery according to any one of claims 1 - 5 above.

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