Roll core structure and zinc-nickel battery

Abstract

The utility model provides a roll core structure and a zinc-nickel battery. The roll core structure is used for the zinc-nickel battery and comprises a positive plate, a first diaphragm, a negative plate and a second diaphragm, the positive plate, the first diaphragm, the negative plate and the second diaphragm are jointly wound to form the roll core structure, the first diaphragm and the second diaphragm both exceed the tail end of the negative plate in the winding direction, and the outer ring of the positive plate is the outer ring of the roll core structure. The positive plate comprises a main body part and an extension part which are sequentially connected along the winding direction; the extension part, the tail end of the first diaphragm, the tail end of the second diaphragm and the main body part are sequentially propped against one another. Therefore, the diaphragm and the positive plate jointly coat the whole outer ring of the negative plate, so that the problem that free alkali liquor between the roll core structure and the inner wall of the steel shell permeates to the surface of the negative plate is avoided, the problem of hydrogen evolution side reaction is avoided, and the performance of the zinc-nickel battery is improved.

Description

Technical Field

[0001] The present disclosure relates to the technical field of zinc-nickel batteries, and in particular, to a core structure and a zinc-nickel battery. Background Art

[0002] The zinc-nickel cylindrical battery has been industrially produced and sold as a commodity. It is a cylindrical battery using zinc and nickel or their compounds as the main electrode materials. This battery combines the respective advantages of zinc and nickel, such as the high energy density and low cost of zinc, and the good electrochemical performance of nickel, thus forming a battery product with unique advantages.

[0003] All zinc-nickel cylindrical batteries use nickel-plated steel as the battery case. According to the conventional winding method of cylindrical batteries, the outermost periphery of the battery electrode group is the negative electrode sheet. The negative electrode active material of the zinc-nickel battery is Zn and ZnO. There is a potential difference between the nickel-iron component steel shell and the negative electrode zinc metal. In an alkaline electrolyte environment, the hydrogen evolution side reaction is serious, resulting in a short cycle life and poor long-term storage performance of the zinc-nickel battery.

[0004] Currently, researchers and related manufacturers in the zinc-nickel field have taken many improvement measures to delay and reduce the side reaction. For example, plating a metal with a high hydrogen evolution potential on the steel shell, using copper foil or tin foil to wrap the electrode group, etc. Although these measures alleviate the hydrogen evolution side reaction to a certain extent, when there is excess free alkali solution in the battery, the free alkali solution will penetrate to the surface of the negative electrode Zn material through the tiny gaps or defects of the copper foil, resulting in the negative electrode Zn material still generating a hydrogen evolution side reaction with the steel shell through the free alkali solution. Summary of the Utility Model

[0005] An object of the present disclosure is to overcome the deficiencies in the prior art and provide a core structure and a zinc-nickel battery that avoid hydrogen evolution side reactions.

[0006] The object of the present disclosure is achieved by the following technical solutions:

[0007] A core structure for a zinc-nickel battery includes a positive electrode sheet, a first separator, a negative electrode sheet, and a second separator. The positive electrode sheet, the first separator, the negative electrode sheet, and the second separator are wound together to form the core structure. The first separator and the second separator both extend beyond the tail end of the negative electrode sheet along the winding direction. The outer circle of the positive electrode sheet is the outer circle of the core structure. The positive electrode sheet includes a main body portion and an extension portion that are sequentially connected along the winding direction. The extension portion, the tail end of the first separator, the tail end of the second separator, and the main body portion are sequentially abutted.

[0008] In some embodiments, the extension portion further extends beyond the tail end of the first separator and abuts against the main body portion.

[0009] In some of these embodiments, the tail end of the first separator extends beyond the tail end of the second separator along the winding direction and abuts against the outer side of the main body portion.

[0010] In some of these embodiments, the extension portion is the outer ring of the positive electrode sheet.

[0011] In some of these embodiments, the main body portion includes a first current collector and an active material layer, the active material layer is formed on the surface of the first current collector, the extension portion includes a second current collector, and the first current collector and the second current collector are sequentially connected along the winding direction.

[0012] In some of these embodiments, a first empty foil area is provided on the outer side of the second current collector, and the first empty foil area is used for electrical connection with the steel shell.

[0013] In some of these embodiments, the first empty foil area is provided on the entire outer side of the second current collector.

[0014] In some of these embodiments, a second empty foil area is provided on the entire inner side of the second current collector.

[0015] A zinc-nickel battery includes the core structure according to any of the above embodiments. The zinc-nickel battery further includes a steel shell. The core structure is disposed within the steel shell, and the inner wall of the steel shell, the extension portion, the tail end of the first separator, the tail end of the second separator, and the main body portion are sequentially abutted.

[0016] In some of these embodiments, the zinc-nickel battery is cylindrical.

[0017] Compared with the prior art, the present disclosure has at least the following advantages:

[0018] Since the outer ring of the positive electrode sheet is the outer ring of the core structure, the outer side of the outer ring of the negative electrode sheet is coated with the first separator and the positive electrode sheet. Also, since the extension portion, the tail end of the first separator, the tail end of the second separator, and the main body portion are sequentially abutted, the tail end edge of the negative electrode sheet is coated with the extension portion of the first separator and the positive electrode sheet. Furthermore, the first separator and the positive electrode sheet jointly coat the entire outer ring of the negative electrode sheet, avoiding the problem that the free alkali solution between the core structure and the inner wall of the steel shell penetrates to the surface of the negative electrode sheet, thereby avoiding the problem of hydrogen evolution side reaction and improving the performance of the zinc-nickel battery. Description of the Drawings

[0019] To more clearly illustrate the technical solutions of the embodiments of the present disclosure, the following will briefly introduce the drawings required for the embodiments. It should be understood that the following drawings only show some embodiments of the present disclosure, and thus should not be regarded as limiting the scope. For those of ordinary skill in the art, other related drawings can be obtained based on these drawings without creative efforts.

[0020] Figure 1 Schematic structural diagram of a zinc-nickel battery according to an embodiment.

[0021] Reference numerals: 10, zinc-nickel battery; 10a, wound core structure;

[0022] 100, positive electrode sheet; 110, main body portion; 120, extension portion; 121, second current collector; 121a, first empty foil area; 121b, second empty foil area;

[0023] 200, first separator;

[0024] 300, negative electrode sheet;

[0025] 400, second separator;

[0026] 10b, steel shell. Detailed implementation manners

[0027] To facilitate the understanding of the present disclosure, the present disclosure will be described more comprehensively below with reference to the relevant drawings. The preferred embodiments of the present disclosure are shown in the drawings. However, the present disclosure can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, these embodiments are provided so that the understanding of the disclosure content of the present disclosure is more thorough and comprehensive.

[0028] It should be noted that when an element is referred to as being "fixed to" another element, it can be directly on the other element or there can also be an intermediate element. When an element is considered to be "connected" to another element, it can be directly connected to the other element or there may be an intermediate element at the same time. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are only for the purpose of illustration and do not represent the only embodiments.

[0029] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the technical field to which the present disclosure belongs. The terms used in the description of the present disclosure herein are only for the purpose of describing specific embodiments and are not intended to limit the present disclosure. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0030] To better understand the technical solutions and beneficial effects of the present disclosure, the present disclosure will be further described in detail below with specific embodiments:

[0031] As Figure 1As shown, the core structure 10a of an embodiment is used for a zinc-nickel battery 10. The core structure 10a includes a positive electrode plate 100, a first separator 200, a negative electrode plate 300, and a second separator 400. The positive electrode plate 100, the first separator 200, the negative electrode plate 300, and the second separator 400 are wound together to form the core structure 10a. Both the first separator 200 and the second separator 400 extend beyond the tail end of the negative electrode plate 300 along the winding direction. Among them, the outer circle of the positive electrode plate 100 is the outer circle of the core structure 10a, so that the outer peripheral side of the core structure 10a is the positive electrode plate 100. The positive electrode plate 100 includes a main body portion 110 and an extension portion 120 that are sequentially connected along the winding direction. The extension portion 120, the tail end of the first separator 200, the tail end of the second separator 400, and the main body portion 110 are sequentially abutted.

[0032] As Figure 1 shown, in this embodiment, after the core structure 10a is installed in the steel shell 10b, the steel shell 10b, the extension portion 120, the tail end of the first separator 200, the tail end of the second separator 400, and the main body portion 110 are sequentially abutted. That is, under the action of the abutting force of the steel shell 10b, the extension portion 120, the tail end of the first separator 200, the tail end of the second separator 400, and the main body portion 110 are sequentially abutted.

[0033] For the above-mentioned core structure 10a, since the outer circle of the positive electrode plate 100 is the outer circle of the core structure 10a, the first separator 200 and the positive electrode plate 100 are coated on the outside of the outer circle of the negative electrode plate 300. Also, since the extension portion 120, the tail end of the first separator 200, the tail end of the second separator 400, and the main body portion 110 are sequentially abutted, the tail end edge of the negative electrode plate 300 is coated with the extension portion 120 of the first separator 200 and the positive electrode plate 100. Furthermore, the first separator 200 and the positive electrode plate 100 jointly coat the entire outer circle of the negative electrode plate 300, avoiding the problem that the free alkali solution between the core structure 10a and the inner wall of the steel shell 10b penetrates to the surface of the negative electrode plate 300. Thus, the problem of hydrogen evolution side reaction is avoided, and the performance of the zinc-nickel battery 10 is improved.

[0034] As Figure 1 shown, in some embodiments, the first separator 200 and the second separator 400 are an integrally formed structure. Of course, in other embodiments, the first separator 200 and the second separator 400 can also be a separately formed structure, that is, a two-piece structure.

[0035] As Figure 1 shown, in some embodiments, the extension portion 120 also extends beyond the tail end of the first separator 200 and abuts against the main body portion 110, so that the extension portion 120 blocks the contact between the free alkali solution and the tail end of the first separator 200, making it more difficult for the free alkali solution to penetrate to the negative electrode plate 300, and improving the effect of blocking the penetration of the free alkali solution to the negative electrode plate 300.

[0036] AsFigure 1 As shown, in some embodiments, the tail end of the first separator 200 extends beyond the tail end of the second separator 400 along the winding direction and abuts against the outer side of the main body portion 110, so that the tail end of the first separator 200 blocks the penetration of the alkaline solution to the tail end of the second separator 400, making it more difficult for the free alkaline solution to penetrate into the negative electrode sheet 300, and improving the effect of blocking the penetration of the free alkaline solution into the negative electrode sheet 300.

[0037] As Figure 1 shown, in some embodiments, the extension portion 120 is the outer ring of the positive electrode sheet 100, that is, the outer ring of the core structure 10a is the extension portion 120, so that the outer ring of the negative electrode sheet 300 is coated with a layer of separator 200, a layer of main body portion 110, and a layer of extension portion 120, making it more difficult for the free alkaline solution to penetrate into the negative electrode sheet 300, and improving the effect of blocking the penetration of the free alkaline solution into the negative electrode sheet 300.

[0038] As Figure 1 shown, in some embodiments, the main body portion 110 includes a first current collector and an active material layer, the active material layer is formed on the surface of the first current collector, the extension portion 120 includes a second current collector 121, and the first current collector and the second current collector 121 are sequentially connected along the winding direction. Further, a first empty foil area 121a is provided on the outer side of the second current collector 121, and the first empty foil area 121a is used for electrical connection with the steel shell 10b. In this embodiment, since the surface of the first empty foil area 121a has good conductivity, the internal resistance of the zinc-nickel battery 10 is reduced, and the performance of the zinc-nickel battery 10 is improved.

[0039] As Figure 1 shown, in some embodiments, the first empty foil area 121a is provided on the entire outer side of the second current collector 121, and the entire outer side surface of the second current collector 121 is used for electrical connection with the steel shell 10b, increasing the electrical connection area between the core structure 10a and the steel shell 10b, further reducing the resistance between the core structure 10a and the steel shell 10b, that is, further reducing the internal resistance of the zinc-nickel battery 10 and improving the performance of the zinc-nickel battery 10.

[0040] As Figure 1 shown, further, a second empty foil area 121b is provided on the entire inner side of the second current collector 121, that is, both the entire inner side and the entire outer side of the second current collector 121 are provided with empty foil areas, making the second current collector 121 a current collector without coated positive electrode material, simplifying the structure of the second current collector 121, and improving the efficiency of manufacturing the positive electrode sheet 100.

[0041] As Figure 1As shown in the figure, the present disclosure also provides a zinc-nickel battery 10, which includes the core structure 10a described in any of the above embodiments. The zinc-nickel battery 10 further includes a steel shell 10b. The core structure 10a is disposed within the steel shell 10b, and the inner wall of the steel shell 10b, the extension portion 120, the tail end of the first separator 200, the tail end of the second separator 400, and the main body portion 110 are sequentially abutted.

[0042] For the above-mentioned zinc-nickel battery 10, since the outer ring of the positive electrode plate 100 is the outer ring of the core structure 10a, the outer side of the outer ring of the negative electrode plate 300 is coated with the first separator 200 and the positive electrode plate 100. Also, due to the sequential abutment of the extension portion 120, the tail end of the first separator 200, the tail end of the second separator 400, and the main body portion 110, the tail end edge of the negative electrode plate 300 is coated with the extension portion 120 of the first separator 200 and the positive electrode plate 100. Furthermore, the first separator 200 and the positive electrode plate 100 jointly coat the entire outer ring of the negative electrode plate 300, avoiding the problem that the free alkali solution between the core structure 10a and the inner wall of the steel shell 10b penetrates to the surface of the negative electrode plate 300, thereby avoiding the problem of hydrogen evolution side reactions and improving the performance of the zinc-nickel battery 10.

[0043] As Figure 1 shown in the figure, in some of the embodiments, the zinc-nickel battery 10 is cylindrical. In this embodiment, since a series of internationally unified standard specifications and models have been formed for cylindrical batteries, the interchangeability of the zinc-nickel battery 10 between different devices is stronger.

[0044] Compared with the prior art, the present disclosure has at least the following advantages:

[0045] For the above-mentioned zinc-nickel battery 10, since the outer ring of the positive electrode plate 100 is the outer ring of the core structure 10a, the outer side of the outer ring of the negative electrode plate 300 is coated with the first separator 200 and the positive electrode plate 100. Also, due to the sequential abutment of the extension portion 120, the tail end of the first separator 200, the tail end of the second separator 400, and the main body portion 110, the tail end edge of the negative electrode plate 300 is coated with the extension portion 120 of the first separator 200 and the positive electrode plate 100. Furthermore, the first separator 200 and the positive electrode plate 100 jointly coat the entire outer ring of the negative electrode plate 300, avoiding the problem that the free alkali solution between the core structure 10a and the inner wall of the steel shell 10b penetrates to the surface of the negative electrode plate 300, thereby avoiding the problem of hydrogen evolution side reactions and improving the performance of the zinc-nickel battery 10.

[0046] The above-described embodiments merely represent several implementation manners of the present disclosure. Their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the disclosed patent. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present disclosure, several modifications and improvements can still be made, and these all belong to the protection scope of the present disclosure. Therefore, the protection scope of the present disclosure patent shall be subject to the appended claims.

Claims

1. A winding core structure for a zinc-nickel battery, comprising a positive electrode sheet (100), a first diaphragm (200), a negative electrode sheet (300) and a second diaphragm (400), wherein the positive electrode sheet (100), the first diaphragm (200), the negative electrode sheet (300) and the second diaphragm (400) are wound together to form the winding core structure, characterized in that: The first diaphragm (200) and the second diaphragm (400) both extend beyond the tail end of the negative electrode sheet (300) in the winding direction; the outer ring of the positive electrode sheet (100) is the outer ring of the winding core structure; the positive electrode sheet (100) comprises a main body (110) and an extension (120) which are sequentially connected in the winding direction; the extension (120), the tail end of the first diaphragm (200), the tail end of the second diaphragm (400) and the main body (110) are sequentially abutted.

2. The winding core structure according to claim 1, characterized in that: The extension portion (120) also extends beyond the rear end of the first diaphragm (200) and abuts against the main body (110).

3. The winding core structure according to claim 1, characterized in that: The tail end of the first diaphragm (200) exceeds the tail end of the second diaphragm (400) along the winding direction and abuts against the outer side of the main body (110).

4. The winding core structure according to claim 1, characterized in that: The extension portion (120) is the outer ring of the positive electrode sheet (100).

5. The winding core structure according to claim 1, characterized in that: The main body (110) comprises a first current collector and an active material layer, wherein the active material layer is formed on the surface of the first current collector, and the extension portion (120) comprises a second current collector (121), wherein the first current collector and the second current collector (121) are sequentially connected along a winding direction.

6. The winding core structure according to claim 5, characterized in that: A first empty foil area (121a) is provided on the outer side of the second current collector (121), and the first empty foil area (121a) is used for being electrically connected to the steel shell (10b).

7. The winding core structure according to claim 6, characterized in that: The first empty foil area (121a) is arranged on the entire outer side of the second current collector (121).

8. The winding core structure according to claim 7, characterized in that: The entire inner side of the second current collector (121) is provided with a second empty foil area (121b).

9. A zinc-nickel battery, characterized in that: The zinc-nickel battery comprises the winding core structure (10a) as described in any one of claim 8, and the winding core structure (10a) is arranged in the steel shell (10b), and the inner wall of the steel shell (10b), the extension part (120), the tail end of the first diaphragm (200), the tail end of the second diaphragm (400) and the main body (110) are abutted in sequence.

10. The zinc-nickel battery according to claim 9, characterized in that: The zinc-nickel battery is cylindrical.

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