Zinc-nickel battery

Abstract

The utility model relates to a zinc-nickel battery. The zinc-nickel battery comprises a pole group, a shell, a cover body and an insulation sleeve, the cover body and the insulation sleeve are in insulation connection with the shell, the cover body covers the shell, the cover body and the shell jointly form a containing cavity, the pole group and the insulation sleeve are both located in the containing cavity, electrolyte is arranged in the containing cavity, the insulation sleeve is arranged on the pole group in a sleeving mode, and the insulation sleeve is arranged in the containing cavity. The pole group is arranged in the shell, so that the pole group is isolated from the shell, and the pole group is electrically connected with the shell and the cover body respectively. According to the scheme provided by the invention, side reaction between the negative electrode and the battery shell can be avoided.

Description

Technical Field

[0001] This application relates to the technical field of batteries, and particularly to a zinc-nickel battery. Background Art

[0002] Currently, commercially available zinc-nickel cylindrical batteries on the market usually use nickel-plated steel as the battery case. There is an inherent potential difference between the nickel, iron and other metals in the case and the negative zinc metal. If the two come into contact, it will cause the entire battery chemical system to be extremely unstable, and side reactions such as hydrogen evolution and passivation will be serious. Therefore, the battery cycle life is short, and the long-term storage capacity recovery performance is poor.

[0003] In related technologies, to solve the problems of unstable battery chemical system and serious side reactions, the battery case is plated with metals with high hydrogen evolution overpotential such as tin / silver to physically isolate the zinc negative electrode from the battery case. However, during the long-term charge and discharge process, the tin / silver layer will undergo electrochemical corrosion, and the negative Zn material will still come into contact with the battery case, resulting in side reactions and affecting the battery performance. Utility Model Content

[0004] To solve or partially solve the problems existing in the related technologies, this application provides a zinc-nickel battery that can avoid side reactions between the negative electrode and the battery case.

[0005] This application provides a zinc-nickel battery, including: a pole group, a case, a cover body and an insulating sleeve that are insulated and connected to the case (2). The cover body covers the case, and the cover body and the case together form a receiving cavity. The pole group and the insulating sleeve are both located in the receiving cavity. An electrolyte is provided in the receiving cavity. The insulating sleeve is sleeved on the pole group to isolate the pole group from the case. The pole group is electrically connected to the case and the cover body respectively.

[0006] Further, the above zinc-nickel battery further includes a positive electrode tab and a negative electrode tab. The pole group is electrically connected to the case through the negative electrode tab, and the pole group is electrically connected to the cover body through the positive electrode tab.

[0007] Further, the positive electrode tab and the negative electrode tab are made of copper or copper plated with tin.

[0008] Further, one end of the negative electrode tab is electrically connected to the pole group, and the other end of the negative electrode tab penetrates through the insulating sleeve and is electrically connected to the case.

[0009] Further, the insulating sleeve is attached to the inner wall surface of the case. The upper end of the insulating sleeve has an opening, and the upper end of the insulating sleeve is attached to the cover body.

[0010] Further, a glue coating is provided on the surface of the cover body close to the receiving cavity.

[0011] Further, the glue coating layer is an asphalt layer.

[0012] Further, the insulating sleeve is made of a thermoplastic elastomer.

[0013] Further, both the housing and the cover are made of nickel-plated steel.

[0014] Further, the electrode assembly is wound by a positive electrode sheet, a negative electrode sheet and a separator.

[0015] The technical solution provided by this application may include the following beneficial effects: By wrapping the electrode assembly with an insulating sleeve, the electrode assembly is isolated from the housing, and the contact between the zinc metal of the negative electrode of the zinc-nickel battery and the nickel and iron metals of the housing to form a micro-battery is isolated. Moreover, the insulating sleeve is resistant to alkaline electrolytes and does not undergo electrochemical corrosion, so that side reactions such as hydrogen evolution and deformation can be reduced during long-term storage and charge-discharge processes, improving the comprehensive performance of the zinc-nickel battery and solving the problems of short cycle life and difficulty in long-term storage of zinc-nickel batteries.

[0016] It should be understood that the above general description and the following detailed description are only exemplary and explanatory, and cannot limit this application. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] By describing the exemplary embodiments of the present application in more detail in conjunction with the drawings, the above and other objects, features, and advantages of the present application will become more obvious. Among them, in the exemplary embodiments of the present application, the same reference numerals generally represent the same components.

[0018] Figure 1 It is a cross-sectional schematic view of the zinc-nickel battery shown in the embodiment of the present application.

[0019] Reference Numerals:

[0020] 1. Electrode assembly; 2. Housing; 3. Cover; 4. Insulating sleeve; 5. Positive electrode tab; 6. Negative electrode tab; 7. Accommodating cavity. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0021] The embodiments of the present application will be described in more detail below with reference to the drawings. Although the embodiments of the present application are shown in the drawings, it should be understood that the present application can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided to make the present application more thorough and complete, and to fully convey the scope of the present application to those skilled in the art.

[0022] It should be understood that although the terms "first", "second", "third", etc. may be used in this application to describe various information, such information should not be limited to these terms. These terms are only used to distinguish information of the same type from each other. For example, without departing from the scope of this application, the first information may also be referred to as the second information, and similarly, the second information may also be referred to as the first information. Thus, features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of this application, "a plurality of" means two or more unless otherwise specifically defined.

[0023] In the description of this application, it should be understood that the orientation or positional relationship indicated by the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing this application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation to this application.

[0024] Unless otherwise clearly specified and limited, the terms "mounted", "connected", "connected to", "fixed", etc. should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection or integrated; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0025] In currently commercially available zinc-nickel cylindrical batteries, nickel-plated steel is usually used as the battery case. The potential difference between metals such as nickel and iron in the case and the negative zinc metal makes the entire battery chemical system extremely unstable, and side reactions such as hydrogen evolution and passivation are serious. Therefore, the battery has a short cycle life and poor long-term storage capacity recovery performance.

[0026] In the related art, to solve the problems of unstable battery chemical system and serious side reactions, the battery case is plated with metals with high hydrogen evolution overpotential such as tin / silver. However, although this measure alleviates the side reactions to a certain extent, it cannot fundamentally solve the problem. During long-term use or storage, the negative Zn material will still have side reactions with the battery case, affecting the battery performance.

[0027] To solve the above problems, an embodiment of this application provides a zinc-nickel battery that can avoid side reactions between the negative electrode and the battery case.

[0028] The technical solutions of the embodiments of this application will be described in detail below with reference to the drawings.

[0029] Figure 1 It is a cross-sectional schematic diagram of the zinc-nickel battery shown in the embodiments of the present application.

[0030] As Figure 1 shown, the embodiments of the present application provide a zinc-nickel battery, which includes a pole group 1, a housing 2, a cover body 3, and an insulating sleeve 4.

[0031] Among them, the cover body 3 is covered on the housing 2, and the cover body 3 is insulated from the housing 2. The cover body 3 and the housing 2 together form a containing cavity 7. Specifically, an opening is provided at the upper end of the housing 2, the cover body 3 is covered on the opening at the upper end of the housing 2, and the cover body 3 and the housing 2 can be connected by welding to form a sealed containing cavity 7.

[0032] The pole group 1 and the insulating sleeve 4 are both located in the containing cavity 7. An electrolyte is provided in the containing cavity 7. The insulating sleeve 4 is sleeved on the pole group 1 to isolate the pole group 1 from the housing 2. The pole group 1 is electrically connected to the housing 2 and the cover body 3 respectively. The positive electrode of the pole group 1 is electrically connected to the cover body 3, and the negative electrode is electrically connected to the housing 2.

[0033] By wrapping the pole group 1 with the insulating sleeve 4, the pole group 1 is isolated from the housing 2, and the negative electrode of the zinc-nickel battery, Zn metal, is isolated from the nickel and iron metals of the housing 2 to form a micro-battery, thereby reducing side reactions such as hydrogen evolution and deformation, improving the comprehensive performance of the zinc-nickel battery, and solving the problems of short cycle life and difficult long-term storage of the zinc-nickel battery.

[0034] It should be noted that the pole group 1 includes at least one battery cell, and the battery cell is a wound battery cell or a stacked battery cell.

[0035] In some embodiments, the amount of alkali injected into the electrolyte is small, which is a lean-alkali electrolyte, so that there is no free alkali solution inside the battery, preventing the negative electrode of the pole group 1 from reacting with the iron and nickel of the housing 2 and the cover body 3 through the alkali solution to produce a micro-battery phenomenon.

[0036] In some embodiments, the zinc-nickel battery further includes a positive electrode tab 5 and a negative electrode tab 6. The pole group 1 is electrically connected to the housing 2 through the negative electrode tab 6, and the pole group 1 is electrically connected to the cover body 3 through the positive electrode tab 5. Specifically, the positive electrode tab 5 is connected to the pole group 1 and the cover body 3 by welding respectively, and the negative electrode tab 6 is connected to the pole group 1 and the housing 2 by welding respectively. By connecting the pole group 1 to the housing 2 and the cover body 3 through the tab connection method, the indirect contact area between the pole group 1 and the housing 2 and the cover body 3 is greatly reduced, the hydrogen evolution side reaction is reduced, the long-term storage performance is improved, and the service life of the battery is extended.

[0037] In some embodiments, the positive electrode tab 5 and the negative electrode tab 6 are made of copper or copper plated with tin. The tabs made of copper or copper plated with tin have good electrical conductivity, no potential difference, and small side reactions.

[0038] In some embodiments, one end of the negative electrode tab 6 is electrically connected to the electrode assembly 1, and the other end of the negative electrode tab 6 penetrates through the insulating sleeve 4 and is electrically connected to the housing 2.

[0039] Specifically, the negative electrode tab 6 penetrates through the bottom of the insulating sleeve 4 and is connected to the bottom surface of the housing 2. The bottom of the insulating sleeve 4 has a certain through-hole at the position of the negative electrode tab 6 for the negative electrode tab 6 to pass through. The insulating sleeve 4 prevents the electrode assembly 1 from contacting the bottom surface of the housing 2.

[0040] In some embodiments, the insulating sleeve 4 is attached to the inner wall surface of the housing 2. The upper end of the insulating sleeve 4 has an opening, and the upper end of the insulating sleeve 4 is fitted with the cover body 3.

[0041] Specifically, the diameter of the opening at the upper end of the insulating sleeve 4 is smaller than the diameter of the electrode assembly 1. The wall surface at the upper end of the insulating sleeve 4 separates the upper end of the electrode assembly 1 from the cover body 3 without contact. The upper end of the electrode assembly 1 is electrically connected to the cover body 3 through the positive electrode tab 5, and the positive electrode tab 5 passes through the opening at the upper end of the insulating sleeve 4.

[0042] In some embodiments, an adhesive layer is provided on the surface of the cover body 3 close to the accommodating cavity 7. Specifically, after the positive electrode tab 5 is welded to the cover body 3 and the electrode assembly 1 respectively, an adhesive layer is coated on the end face of the cover body 3 close to the accommodating cavity 7 to cover the exposed iron-nickel elements on this surface of the cover body 3, which can prevent the electrode assembly 1 from contacting the nickel-iron at the bottom of the cover body 3 through the alkaline solution.

[0043] In some embodiments, the adhesive layer is an asphalt layer. Asphalt has good thermal stability, persistent adhesiveness, elastoplasticity, electrical insulation and water resistance.

[0044] In some embodiments, the insulating sleeve 4 is made of thermoplastic elastomer. For example, the insulating sleeve 4 is made of heat-shrinkable tube.

[0045] In some embodiments, both the housing 2 and the cover body 3 are made of nickel-plated steel.

[0046] In some embodiments, the electrode assembly 1 is wound by a positive electrode plate, a negative electrode plate and a separator. The positive electrode plate is a nickel plate, and the negative electrode plate is a zinc plate.

[0047] The solution of the present application has been described in detail above with reference to the accompanying drawings. In the above embodiments, the descriptions of each embodiment have their own emphases. For the parts not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments. Those skilled in the art should also know that the actions and modules involved in the specification are not necessarily essential to the present application. In addition, it can be understood that the steps in the method embodiments of the present application can be adjusted, combined and deleted according to actual needs, and the modules in the device embodiments of the present application can be combined, divided and deleted according to actual needs.

[0048] The embodiments of the present application have been described above. The above description is exemplary and not exhaustive, and is also not limited to the disclosed embodiments. Many modifications and variations are obvious to those of ordinary skill in the art without departing from the scope and spirit of the described embodiments. The choice of terms used herein is intended to best explain the principles of the embodiments, practical applications, or improvements to technologies in the market, or to enable other ordinary skilled persons in the art to understand the embodiments disclosed herein.

Claims

1. A zinc-nickel battery, characterized in that, Comprising: a pole group (1), a housing (2), a cover (3) insulatedly connected to the housing (2), and an insulating sleeve (4), the cover (3) covering the housing (2), the cover (3) and the housing (2) jointly forming a receiving cavity (7), the pole group (1) and the insulating sleeve (4) both being located in the receiving cavity (7), an electrolyte being provided in the receiving cavity (7), the insulating sleeve (4) sleeving the pole group (1) so as to isolate the pole group (1) from the housing (2), and the pole group (1) being electrically connected to the housing (2) and the cover (3) respectively.

2. The zinc-nickel battery according to claim 1, characterized in that: It further comprises a positive pole tab (5) and a negative pole tab (6), the pole group (1) being electrically connected to the housing (2) through the negative pole tab (6), and the pole group (1) being electrically connected to the cover (3) through the positive pole tab (5).

3. The zinc-nickel battery according to claim 2, characterized in that: The positive pole tab (5) and the negative pole tab (6) are made of copper or copper plated with tin.

4. The zinc-nickel battery according to claim 2, characterized in that: One end of the negative pole tab (6) is electrically connected to the pole group (1), and the other end of the negative pole tab (6) penetrates through the insulating sleeve (4) and is electrically connected to the housing (2).

5. The zinc-nickel battery according to claim 1, characterized in that: The insulating sleeve (4) is attached to the inner wall surface of the housing (2), the upper end of the insulating sleeve (4) has an opening, and the upper end of the insulating sleeve (4) is in contact with the cover (3).

6. The zinc-nickel battery according to claim 1, characterized in that: A glue coating layer is provided on the surface of the cover (3) close to the receiving cavity (7).

7. The zinc-nickel battery according to claim 6, characterized in that: The glue coating layer is an asphalt layer.

8. The zinc-nickel battery according to claim 1, characterized in that: The insulating sleeve (4) is made of a thermoplastic elastomer.

9. The zinc-nickel battery according to claim 1, characterized in that: Both the housing (2) and the cover (3) are made of nickel-plated steel.

10. The zinc-nickel battery according to claim 1, characterized in that: The pole group (1) is wound by a positive electrode plate, a negative electrode plate and a separator.

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