CN214848800U

CN214848800U - Single battery shell, single battery and battery module

Info

Publication number: CN214848800U
Application number: CN202120645815.0U
Authority: CN
Inventors: 刘子文; 陈星宇; 何巍
Original assignee: Hubei Eve Power Co Ltd
Current assignee: Hubei Eve Power Co Ltd
Priority date: 2021-03-30
Filing date: 2021-03-30
Publication date: 2021-11-23
Anticipated expiration: 2031-03-30

Abstract

The utility model relates to a power battery technical field discloses a battery cell shell, battery cell and battery module. The battery cell case includes: battery case and top cap body. The battery case is provided with an opening. The top cap body covers and establishes at the opening part, and welding recess has been seted up to the junction hoop of top cap body and battery case, and one of them end connection of welding recess is in battery case's lateral wall, and another end connection of welding recess is in the lateral wall of top cap body. The utility model discloses reduced the height of welding seam protrusion in battery case, reduced the influence of welding seam height to battery cell shell thickness, reduced battery cell's occupation volume, improved the practicality.

Description

Single battery shell, single battery and battery module

Technical Field

The utility model relates to a power battery technical field especially relates to a battery cell shell, battery cell and battery module.

Background

The shell cover type packaged single batteries in the current market are mostly welded in a laser welding mode, and the welding mode is divided into a top welding mode and a side welding mode. Because square battery is in groups mostly the mode of side by side arrangement, in order to avoid the thickness of battery cell great, adopt the top welding mode more, and cylindrical battery is because the mode of in groups is lower to the width requirement, adopts the mode of side welding more. However, for the fast-charging or hybrid battery, because the requirements on instantaneous power performance and heat dissipation performance are higher, the battery with a square structure is mostly adopted, the thickness of the single battery is generally not more than 20mm, under the condition, if top welding is adopted, because the space of the top cover is insufficient, the distance between the welding line and the pole and the explosion-proof valve is very close, and the laser welding has obvious negative effects on the two parts: firstly, because the welding seam of laser welding is close to the pole, the pole is easy to burn, and the appearance of the single battery is influenced; secondly, because the laser welding seam is close to the explosion-proof valve, the high temperature in the welding process can cause the metal around the explosion-proof valve to generate thermal deformation, thereby influencing the valve opening value of the explosion-proof valve and even causing the failure of the explosion-proof function. And adopt present side welding's mode, can alleviate utmost point post firing problem to a certain extent, but the welding seam that forms after the welding has the height, can increase battery cell's thickness, has increased battery cell's occupation volume, has reduced the practicality, also leads to the energy density that battery cell formed to be lower.

Accordingly, there is a need for a battery cell housing, a battery cell and a battery module to solve the above problems.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to provide a battery cell shell has reduced the height of welding seam protrusion in battery cell shell, has reduced the influence of welding seam height to battery cell shell thickness, has reduced battery cell's occupation volume, has improved the practicality.

To achieve the purpose, the utility model adopts the following technical proposal:

a cell housing, comprising:

a battery case provided with an opening;

the battery cover comprises a top cover body, wherein the top cover body covers the opening, a welding groove is annularly formed in the joint of the top cover body and the battery shell, one tail end of the welding groove is connected to the outer side wall of the battery shell, and the other tail end of the welding groove is connected to the side wall of the top cover body.

As a preferable technical solution of the single battery case, the welding groove includes a first welding recess, the first welding recess is annularly disposed on the edge of the surface of the opening of the battery case, and two ends of the first welding recess are respectively connected to the surface of the opening and the outer sidewall of the battery case.

As a preferred technical solution of the single battery shell, the welding groove further includes a second welding recess, an end surface of the top cover body facing the battery case is a connection end surface, the second welding recess is formed at an edge of the connection end surface of the top cover body, and two ends of the second welding recess are respectively connected to the side wall of the top cover body and the connection end surface; the first welding concave part is opposite to the second welding concave part.

As a preferable mode of the battery cell case, a terminal of the first welding recess on the surface of the opening is in contact with a terminal of the second welding recess on the connection end surface.

As an optimal technical scheme of the single battery shell, the top cover body is provided with a containing groove on the connecting end face, and the containing groove is located inside a cavity enclosed by the battery shell and the top cover body.

As an optimal technical scheme of the single battery shell, the top cover body is provided with an annular stopping portion protruding from the connecting end surface, the stopping portion is arranged between the accommodating groove and the inner side wall of the battery shell, and the inner side wall of the stopping portion is flush with the groove wall of the accommodating groove.

As a preferred technical scheme of the single battery shell, the outer side wall of the battery shell is flush with the side wall of the top cover body.

Another object of the utility model is to provide a battery cell has reduced the height of welding seam protrusion in battery case, has reduced the influence of welding seam height to battery cell thickness, has reduced battery cell's occupation volume, has improved the practicality.

a single battery comprises a battery core and the single battery shell, wherein the battery core is arranged in a cavity defined by the battery shell and the top cover body.

As a preferred technical scheme of the single battery, the welding part is filled in the welding groove, and the welding part is connected with the battery shell and the top cover body.

Another object of the present invention is to provide a battery module, which improves the energy density of the battery module.

a battery module comprises the single battery.

The utility model has the advantages that: the welding groove is formed in the circumferential direction of the joint of the top cover body and the battery shell, when the top cover body is connected with the battery shell in a welding mode, the welding seam can be located inside the welding groove, the height of the welding seam protruding out of the battery shell is reduced, the influence of the height of the welding seam on the thickness of the single battery shell is reduced, the occupied size of the single battery is reduced, and the practicability is improved.

Drawings

Fig. 1 is a schematic structural diagram of a single battery case provided by an embodiment of the present invention;

fig. 2 is a cross-sectional view of a single battery case provided by an embodiment of the present invention;

fig. 3 is a partially enlarged view of a portion a in fig. 2.

In the figure:

1. a battery case;

2. a top cover body; 21. accommodating grooves; 22. a stopper portion;

3. welding the groove; 31. a first welding recess; 32. a second welding recess;

4. a pole column;

5. an explosion-proof valve.

Detailed Description

In order to make the technical problem solved by the present invention, the technical solutions adopted by the present invention and the technical effects achieved by the present invention clearer, the following will be described in further detail with reference to the accompanying drawings, and obviously, the described embodiments are only some embodiments of the present invention, but not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by the skilled in the art without creative work belong to the protection scope of the present invention.

In the description of the present invention, unless expressly stated or limited otherwise, the terms "connected," "connected," and "fixed" are to be construed broadly, e.g., as meaning permanently connected, detachably connected, or integral to one another; can be mechanically or electrically connected; either directly or indirectly through intervening media, either internally or in any other relationship. The specific meaning of the above terms in the present invention can be understood in specific cases to those skilled in the art.

In the present disclosure, unless expressly stated or limited otherwise, the first feature "on" or "under" the second feature may comprise direct contact between the first and second features, or may comprise contact between the first and second features not directly. Also, the first feature being "on," "above" and "over" the second feature includes the first feature being directly on and obliquely above the second feature, or merely indicating that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature includes the first feature being directly under and obliquely below the second feature, or simply meaning that the first feature is at a lesser elevation than the second feature.

The technical solution of the present invention is further explained by the following embodiments with reference to the accompanying drawings.

At present, if top cap and casing are connected to the mode that adopts the side welding, there is the height in the welding formation welding seam, can increase battery cell's thickness, has increased battery cell's occupation volume, has reduced the practicality, also leads to the energy density that battery cell formed to be lower.

This embodiment provides a battery cell shell, has reduced the influence of welding seam height to battery cell shell thickness, has reduced battery cell's occupation volume, has improved the practicality.

Specifically, as shown in fig. 1 to 3, the battery cell case provided in the present embodiment includes: a battery case 1 and a top cover body 2. The battery case 1 is provided with an opening. The opening part is established to top cap body 2 lid, and welding recess 3 has been seted up to the junction hoop of top cap body 2 and battery case 1, and one of them end connection in battery case 1's lateral wall of welding recess 3, another end connection in top cap body 2's lateral wall of welding recess 3. The top cap body 2 is provided with welding groove 3 with battery case 1's junction hoop, and when with top cap body 2 and battery case 1 welded connection, the welding seam can be located inside welding groove 3, has reduced the height of welding seam protrusion in battery case, has reduced the welding seam height to the influence of battery case thickness, has reduced battery cell's occupation volume, has improved the practicality. In the present embodiment, the outer side wall of the battery case 1 is flush with the side wall of the top cover body 2.

Specifically, the welding groove 3 includes a first welding recess 31, the edge of the surface of the opening of the battery case 1 is annularly provided with the first welding recess 31, and both ends of the first welding recess 31 are connected to the surface of the opening and the outer side wall of the battery case 1, respectively. Further, the welding groove 3 further comprises a second welding concave portion 32, the end face of the top cover body 2 facing the battery case 1 is a connection end face, the edge of the connection end face of the top cover body 2 is provided with the second welding concave portion 32, and two tail ends of the second welding concave portion 32 are respectively connected to the side wall of the top cover body 2 and the connection end face; the first welding recess 31 is disposed opposite to the second welding recess 32. Set up first welding concave part 31 and second welding concave part 32, can make the welding seam all be connected with battery case 1 and top cap body 2, guaranteed the joint strength between battery case 1 and the top cap body 2, and set up first welding concave part 31 and second welding concave part 32 respectively and also improved the area of contact of welding seam and battery case 1 and top cap body 2, further improved joint strength.

Specifically, the first welding recess 31 is a groove having a right-angled triangle cross section, two right-angled sides are respectively overlapped with the surface of the opening of the battery case 1 and the outer side wall, and both ends of the oblique side are respectively connected to the surface of the opening and the outer side wall of the battery case 1. Specifically, the second welding recess 32 is a groove having a right-angled triangle-shaped cross section, two right-angled sides coincide with the connection end face and the side wall of the header body 2, and the two ends of the oblique side are connected to the side wall and the connection end face of the header body 2, respectively. The first welding recess 31 is disposed opposite to the second welding recess 32 to form the welding groove 3. In other embodiments, the first welding recess 31 and the second welding recess 32 may also be in the shape of a groove or a fillet having other shapes, which is not limited herein.

Preferably, the end of the first welding recess 31 on the surface of the opening is connected to the end of the second welding recess 32 on the connecting end surface, so that a gap with a small angle is prevented from being formed between the first welding recess 31 and the connecting end surface or between the second welding recess 32 and the surface of the opening of the battery case 1, the welding groove 3 is filled with the welding seam, a gap is prevented from being left between the welding seam and the first welding recess 31 or the second welding recess 32, and the strength of the welding connection is ensured. In the present embodiment, the first welding recess 31 and the second welding recess 32 have the same cross-sectional size and are mirror-symmetrical.

As preferred scheme, holding tank 21 has been seted up on connection terminal surface to top cap body 2, and inside holding tank 21 was located the cavity that battery case 1 and top cap body 2 enclose, holding tank 21 was used for holding the top of electric core, has reduced battery cell shell's height, has further reduced battery cell's occupation volume.

In the present embodiment, in the directions shown in fig. 2 to 3, the thickness from the side wall of the accommodating groove 21 to the side wall of the top cover body 2 is the same as the thickness from the top wall of the accommodating groove 21 to the top wall of the top cover body 2, and is preferably 0.5 to 3 mm. In other embodiments, the two thicknesses may also be different, and are not limited herein.

In the present embodiment, the height difference between the top wall and the connecting end surface of the accommodating groove 21 is 3 to 10mm, preferably 5mm, in the direction shown in fig. 2 to 3.

Preferably, the top cover body 2 is provided with a stopper 22 protruding from the connecting end surface. Between holding tank 21 and battery case 1's inside wall is arranged in to backstop portion 22, when laser welding, set up backstop portion 22 and can block the laser that passes from the gap between battery case 1 and the top cap body 2, avoided the damage of laser to the inside electric core of battery cell shell, guaranteed the qualification rate of product. In this embodiment, the thickness of the stopping portion 22 is smaller than the thickness from the side wall of the accommodating groove 21 to the side wall of the top cover body 2, the thickness of the stopping portion 22 is 0.2-2 mm, the length is 2-5 mm, and the preferable length is 3 mm.

Specifically, the end of the first welding recess 31 on the surface of the opening is spaced from the inner side wall of the battery case 1, and the end of the second welding recess 32 on the connecting end surface is spaced from the stopper portion 22. The contact position between the battery shell 1 and the top cover body 2 is planar, so that the contact area is increased, and the assembly is convenient. In other embodiments, the end of the first welding recess 31 on the surface of the opening may also intersect at the intersection between the inner side wall of the battery case 1 and the surface of the opening, and the end of the second welding recess 32 on the connecting end surface may also intersect at the intersection between the side wall of the stopper portion 22 on the side facing the battery case 1 and the connecting end surface.

Preferably, the stopping portion 22 is annularly disposed on the connecting end surface, and an inner sidewall of the stopping portion 22 is flush with a groove wall of the accommodating groove 21. The stopping part 22 is flush with the groove wall of the accommodating groove 21, so that the processing is convenient, and the processing difficulty is reduced. Further, the outer side wall of the stopping portion 22 is attached to the inner side wall of the battery case 1, so that the structural strength of the joint between the battery case 1 and the top cover body 2 is improved, and the practicability and the durability are improved. In other embodiments, the inner sidewall of the stopping portion 22 and the groove wall of the receiving groove 21 may not be flush, and is not limited herein.

In this embodiment, the cross section of the single battery shell is rectangular, which is suitable for a square battery. The top cover body 2 and the stopping portion 22 are of an integrated structure, and the battery case 1 is also of an integrated structure. And in order to guarantee the welding strength between the battery shell 1 and the top cover body 2, the battery shell 1 and the top cover body 2 are made of the same material, and can be made of steel or aluminum. Aluminum is preferably adopted, so that the weight is light and the cost is low. In other embodiments, the cross section of the single battery shell may also be circular, which is suitable for a cylindrical battery, and is not limited herein.

The embodiment also provides a single battery. Specifically, as shown in fig. 1-3, a battery cell includes a cell and a battery cell housing as previously described herein. The electric core is arranged in a cavity defined by the battery shell 1 and the top cover body 2. Further, the single battery further comprises two poles 4, and the two poles 4 are respectively electrically connected with the positive pole lug and the negative pole lug of the battery core. In this embodiment, the one end of cell casing 1 sets up the opening, and the opening part shutoff has a top cap body 2, and two utmost point posts 4 all set up on this top cap body 2. In other embodiments, both ends of the battery shell 1 of the single battery are provided with openings, so that two top cover bodies 2 are arranged, the two top cover bodies 2 are respectively plugged at the two openings, and two pole columns 4 are respectively arranged on the two top cover bodies 2. Further, be provided with explosion-proof valve 5 on the top cap body 2, when the gas pressure of the inside of battery cell was too big, explosion-proof valve 5 can in time release pressure, avoided the battery cell explosion, improved the security. It can be understood that the welding groove 3 is filled with a welding part, and the welding part is connected to both the battery case 1 and the top cap body 2. Wherein, the welding part is formed by the melted soldering tin during welding and is filled in the welding groove 3 to play a role in connecting the top cover body 2 and the battery shell 1.

The embodiment also provides a battery module. In particular, a single cell as described hereinbefore is included. Specifically, the battery module comprises the single battery as described above, so that the energy density of the battery module is improved, and the practicability is also improved. The battery module comprises a plurality of single batteries arranged along a first direction, and two end plates are respectively arranged at two ends of the battery module along the first direction, namely the plurality of single batteries are arranged between the two end plates. The battery module is provided with a steel belt used for bundling and fixing along the circumferential direction, so that the battery module forms a whole.

It is obvious that the above embodiments of the present invention are only examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. Other variations and modifications will be apparent to persons skilled in the art in light of the above description. And are neither required nor exhaustive of all embodiments. Any modification, equivalent replacement, and improvement made within the spirit and principle of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. A battery cell housing, comprising:

the battery comprises a battery shell (1), wherein the battery shell (1) is provided with an opening;

the battery top cover comprises a top cover body (2), the top cover body (2) is covered at the opening, a welding groove (3) is annularly formed in the joint of the battery shell (1), one end of the welding groove (3) is connected to the outer side wall of the battery shell (1), and the other end of the welding groove (3) is connected to the side wall of the top cover body (2).

2. The battery cell casing according to claim 1, wherein the welding groove (3) includes a first welding recess (31), the first welding recess (31) is formed around the edge of the surface of the opening of the battery case (1), and both ends of the first welding recess (31) are connected to the surface of the opening and the outer side wall of the battery case (1), respectively.

3. The battery cell casing according to claim 2, wherein the welding groove (3) further comprises a second welding recess (32), the end surface of the top cover body (2) facing the battery case (1) is a connection end surface, the second welding recess (32) is opened in the edge of the connection end surface of the top cover body (2), and two ends of the second welding recess (32) are respectively connected to the side wall of the top cover body (2) and the connection end surface; the first welding concave part (31) and the second welding concave part (32) are arranged oppositely.

4. The battery cell case according to claim 3, wherein an end of the first welding recess (31) on the surface of the opening meets an end of the second welding recess (32) on the connection end surface.

5. The battery cell casing according to claim 3, wherein the top cover body (2) has a receiving groove (21) formed on the connecting end surface, and the receiving groove (21) is located inside a cavity surrounded by the battery case (1) and the top cover body (2).

6. The battery cell casing according to claim 5, wherein the top cover body (2) is provided with a ring-shaped stopping portion (22) protruding from the connecting end surface, the stopping portion (22) is disposed between the accommodating groove (21) and the inner side wall of the battery case (1), and the inner side wall of the stopping portion (22) is flush with the groove wall of the accommodating groove (21).

7. The cell casing according to any one of claims 1 to 6, wherein the outer side wall of the battery case (1) is flush with the side wall of the top cover body (2).

8. A single battery, which is characterized by comprising a battery cell and a single battery shell as set forth in any one of claims 1 to 7, wherein the battery cell is arranged in a cavity enclosed by the battery shell (1) and the top cover body (2).

9. The battery cell according to claim 8, wherein the welding groove (3) is filled with a welding part, and the welding part is connected with both the battery case (1) and the top cap body (2).

10. A battery module comprising the unit battery according to claim 8 or 9.