CN221080194U

CN221080194U - Battery shell and battery

Info

Publication number: CN221080194U
Application number: CN202322465738.2U
Authority: CN
Inventors: 李青虎; 吴金波; 李俊杨
Original assignee: Guangdong Kexin Juli New Energy Co ltd
Current assignee: Guangdong Kexin Juli New Energy Co ltd
Priority date: 2023-09-11
Filing date: 2023-09-11
Publication date: 2024-06-04
Anticipated expiration: 2033-09-11

Abstract

The utility model relates to a battery shell and a battery, wherein the battery shell comprises a metal shell and a nano injection molding insulating layer, the metal shell comprises a bottom wall and a side wall, the side wall is of an annular structure, the side wall is connected to the bottom wall and encloses an accommodating space with the bottom wall, the upper end of the metal shell is an open end, the inner surface of the side wall comprises an insulating region and a non-insulating region arranged on the upper side of the insulating region, the non-insulating region is close to the open end, and the inner surface of the bottom wall and the insulating region are both connected with the nano injection molding insulating layer. The nanometer insulating layer that moulds plastics has better corrosion-resistant and high voltage breakdown resistance, and the nanometer insulating layer that moulds plastics is connected on the diapire and the insulating zone of metal casing through the mode of nanometer, consequently, can make the nanometer mould plastics insulating layer high with the joint strength of metal casing, avoid the nanometer insulating layer that moulds plastics to drop, guarantee the insulating effect of insulating layer that moulds plastics to the nanometer.

Description

Battery shell and battery

Technical Field

The utility model relates to the technical field of batteries, in particular to a battery shell and a battery.

Background

In the field of energy storage and power batteries, prismatic batteries generally use a battery housing as the external structure of the cell.

At present, the preparation method of the battery shell is generally that after the battery core is assembled to the battery shell through stretching and forming of a metal plate, the battery shell, a cover plate, a positive electrode connecting sheet and a positive electrode lug are connected, and the battery shell, the cover plate, the positive electrode connecting sheet and the positive electrode lug are positively charged. In order to avoid the internal short circuit of the battery in the use process, an insulating gasket is arranged at the bottom of the battery shell to prevent the contact between the negative electrode winding core and the bottom of the battery shell from causing short circuit, but with the use of the battery, if the exposed black part of the negative electrode is more, namely the part of the edge of the negative electrode plate, which is not covered by the diaphragm, is more, or the insulating gasket is more worn, the negative electrode plate is easy to contact with the bottom of the battery shell to cause micro short circuit, and the problems of self discharge and the like are caused. If the negative electrode contacts with the battery shell, corrosion reaction firstly occurs on the inner wall of the battery shell in the use or storage process of the battery core, and the corrosion reaction further goes deep along with the time, so that the battery shell is damaged.

Disclosure of utility model

An object of the present utility model is to provide a battery case, which solves at least one of the above problems.

In order to achieve the above object, a first aspect of the present utility model provides a battery case, including a metal case and a nano injection molding insulating layer, where the metal case includes a bottom wall and a side wall, the side wall is in an annular structure, the side wall is connected to the bottom wall and encloses an accommodating space with the bottom wall, an upper end of the metal case is an open end, an inner surface of the side wall includes an insulating region and a non-insulating region disposed on an upper side of the insulating region, the non-insulating region is close to the open end, and the inner surface of the bottom wall and the insulating region are both connected with the nano injection molding insulating layer.

Optionally, the thickness of the nano injection molding insulating layer is 1mm-2mm.

Optionally, the nano injection-molded insulating layer is made of polyethylene terephthalate or polypropylene, and/or the metal shell is made of an aluminum alloy.

Optionally, the insulating region and/or the inner surface of the bottom wall is provided with a plurality of recesses.

Optionally, the size of the pit is nano-scale, and/or the distance between two adjacent pits is nano-scale.

Optionally, the height of the uninsulated region is 1mm to 2mm.

Optionally, the annular structure is a cuboid ring.

Another object of the present utility model is to provide a battery to solve at least one of the above technical problems.

To achieve the object, the second aspect of the present utility model adopts the following technical scheme:

A battery comprises the battery shell.

Optionally, the battery further comprises a battery core, and the battery core is arranged in the accommodating space;

The battery also comprises an insulating film, wherein the insulating film is sleeved on the outer side of the circumference of the battery core; and/or the battery further comprises an insulating gasket, wherein the insulating gasket is arranged between the bottom of the battery cell and the bottom wall.

Optionally, the battery further includes a cover plate, and the cover plate is covered at the open end and welded with the non-insulating area.

Therefore, the nano injection molding insulating layer has better corrosion resistance and high voltage breakdown resistance, and is connected to the bottom wall of the metal shell and the insulating region in a nano injection molding mode, so that the connecting strength of the nano injection molding insulating layer and the metal shell is high, the nano injection molding insulating layer is prevented from falling off, and the insulating effect of the nano injection molding insulating layer is ensured.

The nanometer insulating layer that moulds plastics that connects on the diapire can prevent the negative pole of electric core bottom department and the metal casing contact of battery casing, especially when the negative pole black part that leaks is more, can prevent negative pole and metal casing contact, and then prevent that electric core from taking place micro-short circuit and self-discharge phenomenon from taking place to and prevent to take place because of the negative pole of electric core and the diapire contact of metal casing, lead to the diapire of metal casing to take place the corruption. Meanwhile, as the non-insulating area of the side wall is also connected with the nano injection molding insulating layer, when the film at the outermost side of the circumferential direction of the battery core is broken down, or the diaphragm is pierced due to abrasion of particles, the negative electrode of the battery cannot contact with the side wall of the metal shell, so that the short circuit of the battery core can be avoided, and the side wall of the metal shell is prevented from being corroded.

Drawings

Fig. 1 is a schematic view of a battery case according to an embodiment of the present utility model;

fig. 2 is a schematic view of a structure of a battery removing cover plate according to an embodiment of the present utility model;

fig. 3 is an exploded view of a battery provided in an embodiment of the present utility model.

In the figure:

1. a metal shell; 11. a sidewall; 111. a non-insulating region; 12. an accommodation space;

2. A nano injection molding insulating layer;

10. an insulating film; 20. an insulating spacer; 30. a cover plate; 40. and a battery cell.

Detailed Description

The technical scheme of the utility model is further described below by the specific embodiments with reference to the accompanying drawings. It is to be understood that the specific embodiments described herein are merely illustrative of the utility model and are not limiting thereof. It should be further noted that, for convenience of description, only some, but not all of the drawings related to the present utility model are shown.

In the present utility model, directional terms such as "upper", "lower", "left", "right", "inner" and "outer" are used for convenience of understanding, and thus do not limit the scope of the present utility model unless otherwise specified.

In the present utility model, unless expressly stated or limited otherwise, a first feature "above" or "below" a second feature may include both the first and second features being in direct contact, as well as the first and second features not being in direct contact but being in contact with each other through additional features therebetween. Moreover, a first feature being "above," "over" and "on" a second feature includes the first feature being directly above and obliquely above the second feature, or simply indicating that the first feature is higher in level than the second feature. The first feature being "under", "below" and "beneath" the second feature includes the first feature being directly under and obliquely below the second feature, or simply means that the first feature is less level than the second feature.

In the description of the present utility model, unless explicitly stated and limited otherwise, the terms "connected," "connected," and "fixed" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communicated with the inside of two elements or the interaction relationship of the two elements. The specific meaning of the above terms in the present utility model will be understood in specific cases by those of ordinary skill in the art.

The embodiment provides a battery case, which is mainly used for fixing a battery cell 40 to improve insulation stability between the battery case and the battery cell 40, prevent the battery cell 40 from electrically contacting the battery case, prevent the battery cell 40 from being shorted, and prevent the battery case from being corroded.

As shown in fig. 1, the battery case provided in this embodiment includes a metal case 1 and a nano injection molding insulating layer 2, where the metal case 1 includes a bottom wall and a side wall 11, the side wall 11 is in an annular structure, the side wall 11 is connected to the bottom wall and encloses an accommodating space 12 with the bottom wall, and the upper end of the metal case 1 is an open end, so that the battery 40 can conveniently enter the accommodating space 12 from the open end. It is understood that the annular structure refers to a closed structure that extends continuously in the circumferential direction, and in one particular embodiment is a rectangular parallelepiped ring to house the cells 40 that are generally rectangular in shape and form square cells. Of course, in other alternative embodiments, the annular structure may also be a ring or the like. Alternatively, the metal case 1 is made of an aluminum alloy having high strength, which can have sufficient strength to protect the battery cell 40 at a small thickness, improving the energy density of the battery.

The inner surface of the side wall 11 comprises an insulating region and a non-insulating region 111 arranged on the upper side of the insulating region, the non-insulating region 111 is close to the opening end, and the inner surface of the bottom wall and the insulating region are both connected with a nano injection molding insulating layer 2. Optionally, on the inner surface inside the metal shell 1, the insulating region is adjacent to the bottom wall, i.e. the insulating region is connected to the edge of the bottom wall, the upper side of the insulating region is a non-insulating region 111, and the upper side of the non-insulating region 111 is an open end.

Preferably, the inner surface of the whole bottom wall is connected with the nano injection molding insulating layer 2, and the nano injection molding insulating layer 2 connected on the bottom wall and the nano injection molding insulating layer 2 connected on the side wall 11 are preferably of an integrated structure, and are injection molded in one mold.

The nanometer insulating layer 2 of moulding plastics has better corrosion-resistant and high voltage breakdown resistance, and the insulating layer 2 of moulding plastics through the mode of nanometer is connected on the diapire and the insulating zone of metal casing 1, consequently, can make the insulating layer 2 of moulding plastics of nanometer high with the joint strength of metal casing 1, avoids the insulating layer 2 of moulding plastics of nanometer to drop, guarantees the insulating effect of insulating layer 2 of moulding plastics of nanometer.

The nano injection molding insulating layer 2 connected to the bottom wall can prevent the negative electrode at the bottom of the battery cell 40 from contacting the metal shell 1 of the battery shell, especially when the black leakage part of the negative electrode is more, the negative electrode can be prevented from contacting the metal shell 1, so as to prevent the micro short circuit and self discharge of the battery cell 40, and prevent the bottom wall of the metal shell 1 from being corroded due to the contact between the negative electrode of the battery cell 40 and the bottom wall of the metal shell 1. Meanwhile, since the non-insulating region 111 of the sidewall 11 is also connected with the nano injection-molded insulating layer 2, when the outermost thin film of the battery cell 40 in the circumferential direction is broken down or the separator is pierced by particles due to abrasion of the separator, the negative electrode of the battery does not contact with the sidewall 11 of the metal case 1, so that the battery cell 40 can be prevented from being shorted and the sidewall 11 of the metal case 1 can be prevented from being corroded.

Furthermore, in order to further improve the connection strength of the nano injection molding insulating layer 2 and the metal shell 1, a plurality of pits are arranged on the inner surface of the insulating region and/or the bottom wall. The concave pits can increase the roughness of the inner surface of the metal shell 1, and improve the connection strength of the nano injection molding insulating layer 2 and the metal shell 1.

Still further, the size of the pits is nano-scale, and/or the spacing of adjacent pits is nano-scale. To form the nano-scale pits, and/or to make the distance between the pits nano-scale, the metal shell 1 is illustratively treated in such a manner as to form the pits (especially when the metal shell 1 is made of an aluminum alloy): alkali etching is carried out on the surface of the metal shell 1; the metal shell 1 is put into a phosphoric acid solution to be anodized, and an oxide film is formed on the surface of the metal shell 1, so that nano-scale pores are formed in the oxide film.

Optionally, the alkali etching is performed in an alkali etching solution with an alkali concentration of 60-100g/L and a temperature of 50-60 ℃, and the alkali etching time is 90-120 seconds. For example, the alkali in the alkali etching solution may include caustic soda as a main component. During anodic oxidation, the concentration of phosphoric acid in the phosphoric acid solution is 160-220g/L, the temperature of the phosphoric acid solution is controlled at 16-20 ℃, the voltage is controlled at 24-40V, and the oxidation time is controlled at 12-25 minutes. After anodic oxidation, the metal shell 1 may be washed with water and dried, and then the metal shell 1 may be subjected to injection molding of the nano injection molding insulating layer 2.

The metal shell 1 adopts a nano injection molding process, and metal scraps generated in the preparation process of the metal shell 1 can be effectively cleaned through four working procedures of alkali liquor, acid washing, water washing and drying, so that the metal scraps are prevented from being introduced into the battery to cause short circuit. The nano injection molding insulating layer 2 subjected to nano injection molding is not easy to fall off, has the advantages of strong electrolyte corrosion resistance, wear resistance, high voltage breakdown resistance and the like, and improves the safety of the battery cell 40.

It is understood that the alkaline etching and anodic oxidation parameters can be appropriately changed according to the size of the pit, other steps can be added according to the requirement, or other methods can be adopted to form the pit, and the pit forming method is not an utility model point of the present utility model, so that the description is omitted here.

Optionally, the thickness of the nano injection molding insulating layer 2 is 1mm-2mm, so that the insulating effect of the nano injection molding insulating layer 2 is ensured on the premise of ensuring the energy density of the battery as much as possible. The nano injection molding insulating layer 2 is made of polyethylene terephthalate or polypropylene, and the polyethylene terephthalate and the polypropylene have good electrolyte corrosion resistance.

As shown in fig. 2 and 3, the present embodiment provides a battery, which includes the battery case described above, and the performance stability provided in the present embodiment is good.

Optionally, the battery further includes a battery cell 40, where the battery cell 40 is disposed in the accommodating space 12 and can enter and exit the accommodating space 12 through the open end.

The battery can also comprise an insulating film 10, the insulating film 10 is sleeved on the outer side of the circumference of the battery cell 40, the insulating film 10 can be of an annular structure, the specific shape of the annular structure can be matched with the circumferential outline of the battery cell 40, if the battery cell 40 is a cuboid battery cell 40, and the insulating film 10 surrounds into a square ring. The insulating film 10 may be a Mylar film.

The battery may further include an insulating spacer 20, the insulating spacer 20 being disposed between the bottom and bottom walls of the cell 40, optionally the thickness of the insulating spacer 20 is greater than the thickness of the Mylar film, e.g., the thickness of the insulating spacer 20 may be 2mm-4mm. The insulating spacer 20 may be made of plastic or the like. The insulating spacer 20 may further prevent the negative electrode of the cell 40 from contacting the bottom wall of the battery case.

The battery may further include a cap plate 30, the cap plate 30 being disposed at the open end and welded to the non-insulating region 111. The cover plate 30 may seal the open end to prevent water or the like from entering the accommodating space 12.

In order to avoid that the nano injection-molded insulating layer 2 influences the welding of the cover plate 30, the height of the non-insulating region 111 is optionally 1mm-2mm, so that the cover plate 30 is welded with the non-insulating region 111. The height of the non-insulating region 111 may be selected according to specific needs, i.e., the height of the nano-injection-molded insulating layer 2 attached to the sidewall 1 may be set according to needs.

While the utility model has been described in detail in the foregoing general description, embodiments and experiments, it will be apparent to those skilled in the art that modifications and improvements can be made thereto. Accordingly, such modifications or improvements may be made without departing from the spirit of the utility model and are intended to be within the scope of the utility model as claimed.

Claims

1. The utility model provides a battery housing, its characterized in that includes metal casing (1) and nanometer insulating layer (2) of moulding plastics, metal casing (1) includes diapire and lateral wall (11), lateral wall (11) are annular structure, lateral wall (11) connect in on the diapire, and with the diapire encloses into accommodation space (12), the upper end of metal casing (1) is the open end, the internal surface of lateral wall (11) include the insulating region with set up in insulating region upside's uninsulated district (111), uninsulated district (111) are close to the open end, the internal surface of diapire with the insulating region all is connected with nanometer insulating layer (2) of moulding plastics.

2. Battery housing according to claim 1, characterized in that the thickness of the nano injection-molded insulating layer (2) is 1mm-2mm.

3. Battery housing according to claim 1, characterized in that the nano injection-molded insulating layer (2) is made of polyethylene terephthalate or polypropylene and/or the metal shell (1) is made of an aluminum alloy.

4. The battery housing according to claim 1, wherein the insulating region and/or the inner surface of the bottom wall is provided with a plurality of dimples.

5. The battery case according to claim 4, wherein the size of the pits is nano-scale, and/or the pitch of two adjacent pits is nano-scale.

6. The battery housing according to claim 1, characterized in that the height of the uninsulated region (111) is 1mm-2mm.

7. The battery case according to any one of claims 1 to 6, wherein the annular structure is a rectangular parallelepiped ring.

8. A battery comprising the battery case according to any one of claims 1 to 7.

9. The battery according to claim 8, further comprising a cell (40), the cell (40) being disposed within the receiving space (12);

The battery also comprises an insulating film (10), wherein the insulating film (10) is sleeved on the outer side of the circumference of the battery cell (40); and/or the battery further comprises an insulating gasket (20), wherein the insulating gasket (20) is arranged between the bottom of the battery cell (40) and the bottom wall.

10. The battery according to claim 9, further comprising a cover plate (30), said cover plate (30) being provided over said open end and welded to said non-insulating region (111).