Battery shell and lithium battery

Abstract

The utility model belongs to the technical field of battery manufacturing, and discloses a battery shell and a lithium battery, the battery shell comprises a shell and a combined plastic part, the shell is used for placing a battery cell, the shell is provided with a through hole, a tab of the battery cell extends out of the through hole, the combined plastic part comprises a second plastic part and a first plastic part, the first plastic part is of a flat plate structure and is attached to the face, provided with the through hole, of the shell, the second plastic part is attached to the first plastic part, the first plastic part is provided with a first through hole corresponding to the through hole, the second plastic part is provided with a second through hole corresponding to the first through hole, the face, attached to the first plastic part, of the second plastic part is provided with a peripheral part, and the peripheral part is arranged around the second through hole. The peripheral part can penetrate through the first through hole to be inserted into the through hole and is in interference fit with the through hole; a containing groove is formed in the face, away from the peripheral part, of the second plastic part and used for containing the connecting piece. The combined plastic part and the shell are stably assembled, the connecting pieces are not easy to misplace, the deformation probability of the tabs is reduced, the short-circuit risk of the lithium battery is reduced, and the use safety of the lithium battery is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of battery manufacturing, in particular to a battery shell and a lithium battery. Background Art

[0002] Lithium batteries have the advantages of small size, high cycle life and high energy density. They are widely used in the field of new energy and provide power sources for equipment or new energy vehicles. Therefore, the stability of lithium battery performance is increasingly valued by battery manufacturers and consumers. A lithium battery includes a protective shell and a battery cell. The battery cell is placed in the protective shell, and then the tabs on the battery cell are connected to the poles on the protective shell through connecting pieces to realize charging and discharging of the lithium battery. In order to facilitate the installation of the connecting piece, the existing lithium battery adds a composite plastic part, assembles the connecting piece with the composite plastic part, and then places the composite plastic part equipped with the connecting piece in the protective shell. However, the existing composite plastic part and the protective shell are separate structures and the layout of the battery cell in the protective shell is poor. When the lithium battery vibrates, the composite plastic part will shake, causing the connecting piece on the composite plastic part to be misaligned, and then the tabs will be deformed, which can easily cause the lithium battery to short-circuit, exacerbating the risk of using the lithium battery.

[0003] Therefore, there is an urgent need for a battery housing and a lithium battery to solve the above technical problems. Utility Model Content

[0004] The purpose of the utility model is to provide a battery housing and a lithium battery, which can solve the problem that when the lithium battery vibrates, the assembled plastic parts will shake, the connecting pieces will be misaligned, and the tabs will be deformed, which can easily cause the lithium battery to short-circuit and increase the risk of using the lithium battery.

[0005] To achieve this purpose, the present invention adopts the following technical solutions:

[0006] A battery housing, comprising:

[0007] A shell, the shell is used to place the battery core, and the shell is provided with a through hole;

[0008] A combined plastic part includes a first plastic part and a second plastic part, wherein the first plastic part is a flat plate structure, and the first plastic part is in contact with the side of the shell provided with the through hole, and the second plastic part is in contact with the first plastic part, and the first plastic part is provided with a first through hole corresponding to the through hole, and the second plastic part is provided with a second through hole corresponding to the first through hole, and the second plastic part is provided with an outer portion on the side in contact with the first plastic part, and the outer portion is arranged around the second through hole, and the outer portion can pass through the first through hole and be inserted into the through hole and interference fit with the through hole; the second plastic part is provided with a receiving groove on the side away from the outer portion, and the receiving groove is used to place a connecting piece.

[0009] As a preferred technical solution for the battery housing, the combined plastic part includes two second plastic parts, and the two second plastic parts are spaced apart from the first plastic part.

[0010] As a preferred technical solution of the battery housing, the accommodating groove is arranged parallel to the second through hole.

[0011] As a preferred technical solution for the battery housing, the thickness of the combined plastic part is 1 mm to 10 mm.

[0012] As a preferred technical solution of the battery housing, the outer wall of the peripheral portion is provided with interference ribs; and / or the inner wall of the through hole is provided with interference ribs.

[0013] As a preferred technical solution for the battery housing, the top surface or the bottom surface of the interference rib is provided with a chamfer.

[0014] As a preferred technical solution for the battery housing, a plurality of the interference ribs are provided, and the plurality of the interference ribs are spaced apart on the outer wall of the peripheral portion; or, the plurality of the interference ribs are spaced apart on the inner wall of the through hole.

[0015] As a preferred technical solution for the battery shell, the through hole is a strip-shaped hole, and the inner wall of the through hole along the length direction is provided with at least two of the interference ribs, and the inner wall of the through hole along the width direction is provided with at least one of the interference ribs; or, the side wall of the peripheral portion along the length direction is provided with at least two of the interference ribs, and the side wall of the peripheral portion along the width direction is provided with at least one of the interference ribs.

[0016] As a preferred technical solution of the battery housing, the battery housing further includes an explosion-proof valve, which is provided on the housing.

[0017] A lithium battery comprises a battery cell and a connecting piece, the lithium battery further comprising a battery shell as described in any one of the above items, the battery cell is placed in the shell, the connecting piece is placed in the accommodating groove of the second plastic part, and the tab on the battery cell passes through the through hole, the first through hole and the second through hole and is connected to the connecting piece.

[0018] The beneficial effects of the utility model are:

[0019] The battery shell provided by the present invention is provided with an outer portion on a side where the second plastic part and the first plastic part are in contact, and the outer portion is arranged around the second through hole. When the second plastic part is assembled, the outer portion can pass through the first through hole and be inserted into the through hole and interference fit with the through hole. In this way, the second plastic part and the shell are interference fit. When the lithium battery vibrates, the second plastic part and the shell can be stably assembled together, and the second plastic part will not be separated from the shell, thereby reducing the risk of misalignment of the connecting piece, and further reducing the risk of deformation of the pole ear and easy short circuit of the lithium battery, so that the safety of the lithium battery is guaranteed; a receiving groove is provided on the side of the second plastic part away from the outer portion, and the receiving groove is used to place the connecting piece. The setting of the receiving groove can limit the position of the connecting piece, and further limit the shaking range of the connecting piece. When the lithium battery vibrates, the pole ear will not be seriously deformed, and the risk of short circuit of the lithium battery can be effectively reduced, thereby further improving the safety factor of the lithium battery.

[0020] The lithium battery provided by the utility model has a stable connection between the combined plastic parts and the shell, which can ensure that the connecting piece is firmly placed, avoid the occurrence of lithium battery short circuit problems caused by deformation of the tabs, and the overall safety factor of the lithium battery is high during use. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is an exploded view of the battery housing provided in the first embodiment of the present invention from a first perspective;

[0022] Figure 2 yes Figure 1 A magnified schematic diagram of part A in FIG;

[0023] Figure 3 This is a schematic structural diagram of the second plastic part of the battery housing provided in the first embodiment of the present invention;

[0024] Figure 4 This is a schematic structural diagram of a battery housing provided in Example 1 of the present utility model;

[0025] Figure 5 This is a schematic structural diagram of the battery housing provided by the first embodiment of the present invention from a first perspective;

[0026] Figure 6 This is a schematic structural diagram of the battery housing provided by the first embodiment of the present invention from a second perspective;

[0027] Figure 7 This is a schematic structural diagram of the battery housing provided by the first embodiment of the present invention from a third perspective.

[0028] In the picture:

[0029] 1. Liquid injection hole;

[0030] 10. Shell; 11. Through hole; 20. Combined plastic part; 21. First plastic part; 211. First through hole; 22. Second plastic part; 221. Second through hole; 222. Peripheral portion; 223. Accommodating groove; 30. Interference rib; 40. Explosion-proof valve. DETAILED DESCRIPTION

[0031] The present invention will be further described in detail below with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are intended only to illustrate the present invention and are not intended to limit the present invention. It should also be noted that, for ease of description, the accompanying drawings only illustrate portions relevant to the present invention, not all of its components.

[0032] In the description of this utility model, unless otherwise specified or limited, the terms "connected," "connect," and "fixed" should be understood in a broad sense. For example, they can refer to fixed connection, detachable connection, or integration; mechanical connection or electrical connection; direct connection or indirect connection through an intermediate medium; internal communication between two components or interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in this utility model based on the specific circumstances.

[0033] In the present invention, unless otherwise expressly specified or limited, a first feature being "above" or "below" a second feature may include the first and second features being in direct contact, or may include the first and second features being in contact not directly but through another feature between them. Moreover, a first feature being "above," "above," and "above" a second feature may include the first feature being directly above or obliquely above the second feature, or may simply mean that the first feature is higher in level than the second feature. A first feature being "below," "below," and "below" a second feature may include the first feature being directly below or obliquely below the second feature, or may simply mean that the first feature is lower in level than the second feature.

[0034] In the description of this embodiment, the terms "upper," "lower," "right," and other orientations or positional relationships are based on the orientations or positional relationships shown in the accompanying drawings and are intended solely for ease of description and simplified operation. They do not indicate or imply that the devices or components referred to must have a specific orientation, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limitations on the present invention. Furthermore, the terms "first" and "second" are used solely for descriptive purposes and have no special meaning.

[0035] Example 1

[0036] like Figures 1 to 5As shown, this embodiment provides a battery case, including a case 10 and a composite plastic part 20. The case 10 is used to place the battery cell. A through hole 11 is provided on the case 10. The tabs of the battery cell extend from the through hole 11, avoiding placing the tabs inside the case 10. The internal space of the case 10 can be released, and the battery cells can be reasonably arranged in the case 10, thereby improving the safety of lithium batteries. The assembled plastic part 20 includes a first plastic part 21 and a second plastic part 22. The first plastic part 21 is a flat structure and is fitted with a side of the shell 10 provided with the through hole 11. The first plastic part 21 is fixedly connected to the shell 10. The first plastic part 21 is provided with a first through hole 211 corresponding to the through hole 11, and the second plastic part 22 is provided with a second through hole 221 corresponding to the first through hole 211. A peripheral portion 222 is provided on a side of the second plastic part 22 that is fitted with the first plastic part 21. The peripheral portion 222 is arranged around the second through hole 221. When the second plastic part 22 is assembled, the peripheral portion 222 can pass through the first through hole 211 and be inserted into the through hole 11 and interference fit with the through hole 11. In this way, the second plastic part 22 and the shell 10 are interference fit. When the lithium battery vibrates, the second plastic part 22 and the shell 10 can be stably assembled together, and the second plastic part 22 will not be detached from the shell 10, reducing the risk of misalignment of the connecting piece, thereby reducing the risk of the tab deformation easily causing a short circuit in the lithium battery, so that the safety of the lithium battery is guaranteed. A receiving groove 223 is provided on the side of the second plastic part 22 away from the outer portion 222. The receiving groove 223 is used to place the connecting piece. The setting of the receiving groove 223 can limit the position of the connecting piece, thereby limiting the shaking range of the connecting piece. When the lithium battery vibrates, the tab will not be seriously deformed, and the risk of lithium battery short circuit can be effectively reduced, thereby further improving the safety factor of lithium battery use.

[0037] The first plastic part 21 is connected to the housing 10 by bonding. Of course, the connection between the two can also be completed by clamping, welding, bolting, etc., and there is no specific limitation.

[0038] In this embodiment, the battery housing further includes a protective cover, which is used to cover the mounting groove 212 to protect the connecting piece.

[0039] When assembling a lithium battery, the staff first assembles the composite plastic part 20 with the shell 10, places the battery cell into the shell 10, and passes the tabs of the battery cell through the through holes 11 and the tab holes, installs the connecting piece on the composite plastic part 20, welds the tabs to the connecting piece, and places the protective cover on the installation groove 212 to protect the connecting piece.

[0040] In this embodiment, the combined plastic component 20 includes two second plastic components 22. The internal connectors for the lithium battery include positive and negative electrode connectors. A positive electrode connector is placed in the corresponding receiving groove 223 of one second plastic component 22, while a negative electrode connector is placed in the receiving groove 223 of the other second plastic component 22, to meet the design requirements of the lithium battery. The two second plastic components 22 are spaced apart on the first plastic component 21, further improving the rationality of the design of the combined plastic component 20. This also prevents contact between the positive and negative electrode connectors, preventing short circuits in the lithium battery and improving the safety of the lithium battery.

[0041] Preferably, the accommodating groove 223 is arranged parallel to the second through hole 221, so that the pole ear of the battery cell passes through the through hole 11, the first through hole 211 and the second through hole 221 in sequence, and can be fitted with the connecting piece after bending, which is convenient for the staff to assemble the pole ear and the connecting piece, and is more convenient for the welding work of the pole ear and the connecting piece, thereby reducing the difficulty of assembling the lithium battery.

[0042] Preferably, the thickness of the assembled plastic part 20 is 1 mm to 10 mm. If the thickness of the assembled plastic part 20 is too small, it will not be conducive to the protection of the assembled plastic part 20 on the housing 10, and the housing 10 cannot be guaranteed to be used for a long time, which in turn affects the performance of the battery cell and the service life of the lithium battery. If the assembled plastic part 20 is too thick, the overall weight of the lithium battery will be too high and the manufacturing cost will increase. The thickness of the assembled plastic part 20 varies depending on the design of the lithium battery. The thickness of the assembled plastic part 20 can be 2 mm, 4 mm, 6 mm, or 8 mm, and is not specifically limited here.

[0043] Regarding the interference fit between the outer portion 222 and the through-hole 11, for example, interference ribs 30 may be provided on the outer wall of the outer portion 222. When the assembly plastic part 20 and the housing 10 are assembled, the interference ribs 30 on the outer portion 222 abut against the inner wall of the through-hole 11, allowing the two to interference fit. Of course, the interference ribs 30 may also be provided on the inner wall of the through-hole 11 to achieve interference fit between the assembly plastic part 20 and the housing 10 after assembly. Of course, interference ribs 30 may also be provided on both the outer wall of the outer portion 222 and the inner wall of the through-hole 11 to allow interference fit between the two after assembly.

[0044] Preferably, the top or bottom surface of the interference rib 30 is provided with a chamfer. When the interference rib 30 is set on the inner wall of the through-hole 11, the top surface of the interference rib 30 is provided with a chamfer. When the interference rib 30 is set on the outer wall of the peripheral portion 222, the bottom surface of the interference rib 30 is provided with a chamfer. In this way, when the staff assembles the shell 10 and the combined plastic part 20, the combined plastic part 20 can quickly enter the through-hole 11 through the chamfer of the top or bottom surface of the interference rib 30. The chamfer provided on the top or bottom surface of the interference rib 30 can play a certain guiding role when assembling the shell 10 and the combined plastic part 20, allowing the staff to assemble the shell 10 and the combined plastic part 20 more smoothly and quickly. The size of the chamfer is C0.5. C stands for C chamfer, which refers to processing a surface with a specified angle on the corner of the material. C0.5 means a 45-degree chamfer, and the length of the right-angle side is 0.5mm. The dimensions of chamfers are common knowledge in the mechanical field and will not be elaborated here.

[0045] In this embodiment, a plurality of interference ribs 30 are provided. When the interference ribs 30 are provided on the peripheral portion 222, the plurality of interference ribs 30 are spaced apart on the outer wall of the peripheral portion 222. Preferably, at least one interference rib 30 is provided on each outer side surface of the peripheral portion 222 to improve the rationality of the layout of the interference ribs 30 on the peripheral portion 222. When the interference ribs 30 are provided on the through hole 11, the plurality of interference ribs 30 are spaced apart on the inner wall of the through hole 11. Preferably, at least one interference rib 30 is provided on each inner wall of the through hole 11 to improve the rationality of the layout of the interference ribs 30 on the through hole 11. By providing a plurality of interference ribs 30, when the shell 10 and the composite plastic part 20 are assembled, a multi-point interference fit will be achieved between the two, making the assembly of the two more stable and further improving the safety of the lithium battery.

[0046] Specifically, the through-hole 11 in the housing 10 is a strip-shaped hole, and thus both the first through-hole 211 and the second through-hole 221 are strip-shaped holes. Regarding the layout of the interference ribs 30, in this embodiment, when the interference ribs 30 are disposed on the inner wall of the through-hole 11, at least two interference ribs 30 are disposed along the inner wall along the length direction of the through-hole 11, and at least one interference rib 30 is disposed along the inner wall along the width direction. When the interference ribs 30 are disposed on the outer wall of the peripheral portion 222, at least two interference ribs 30 are disposed along the sidewall along the length direction of the peripheral portion 222, and at least one interference rib 30 is disposed along the sidewall along the width direction, thereby further improving the rationality of the layout of the interference ribs 30.

[0047] Preferably, the cross-sectional shape of the interference rib 30 is a rectangle to facilitate processing of the interference rib 30. The cross-sectional shape of the interference rib 30 may also be other regular shapes, such as a pentagon, a hexagon, etc. Of course, the cross-sectional shape of the interference rib 30 may also be an irregular shape, such as a closed shape with a wavy surface. The shape of the interference rib 30 is not specifically limited herein.

[0048] Preferably, the interference margin of the interference rib 30 is 0.05mm-0.3mm. That is, the interference rib 30 protrudes 0.05mm-0.3mm relative to the outer wall of the peripheral portion 222 or the inner wall of the through-hole 11. This ensures that the peripheral portion 222 can be inserted into the through-hole 11 while ensuring a stable assembly of the two. Of course, the interference margin of the interference rib 30 can be adjusted accordingly depending on the specifications of the peripheral portion 222 and the through-hole 11. The interference margin of the interference rib 30 is not specifically limited herein.

[0049] Preferably, when the interference rib 30 is provided on the outer wall of the peripheral portion 222, the interference rib 30 and the peripheral portion 222 are integrally formed, which not only facilitates the processing of the assembled plastic part 20 but also further improves the stability of the assembly of the assembled plastic part 20 and the housing 10. When the interference rib 30 is provided on the through hole 11, the interference rib 30 and the through hole 11 are integrally formed.

[0050] In this embodiment, the combined plastic part 20 is configured as a separate structure of the second plastic part 22 and the first plastic part 21. During the lithium battery manufacturing process, the second plastic part 22 is required to perform different functions depending on the lithium battery design. In some lithium batteries, the second plastic part 22 performs a conductive function, while in others, the second plastic part 22 performs an insulating function. Therefore, the type of second plastic part 22 varies in different lithium batteries. By forming the second plastic part 22 and the first plastic part 21 into a separate structure, the staff can assemble them according to the design requirements to obtain a combined plastic part 20 that meets the design requirements, thereby reducing the processing difficulty of the combined plastic part 20.

[0051] In this embodiment, Figures 5 to 7 As shown, the battery housing also includes an explosion-proof valve 40, which is disposed on the housing 10, specifically between the two second plastic parts 22. When an abnormality occurs in the lithium battery, reactions may occur within the battery, such as electrolyte evaporation, electrolyte oxidation and decomposition, or reactions between the negative electrode and the electrolyte. During these reactions, a large amount of gas is generated within the battery. The provision of the explosion-proof valve 40 can release the gas generated within the battery, reducing the risk of explosion. The specific structure and principle of the explosion-proof valve 40 can be referenced in the prior art. It is not a key aspect of this embodiment and will not be further described here.

[0052] Example 2

[0053] This embodiment provides a lithium battery, including a battery cell and a connecting piece, and also includes the battery shell of Example 1. The battery cell is placed in the shell 10, and the connecting piece is placed in the receiving groove 223 of the second plastic part 22. The electrode tab on the battery cell passes through the through hole 11, the first through hole 211 and the second through hole 221, and is fitted with the connecting piece and welded to the connecting piece.

[0054] In this embodiment, Figures 4 to 6 As shown, the lithium battery also includes an injection port 1, which is provided on the housing 10. The provision of the injection port 1 facilitates the operator to inject the electrolyte into the lithium battery according to the designed required amount, thereby ensuring the use of the lithium battery. At the same time, when the electrolyte in the lithium battery needs to be replenished, the replenished electrolyte can also be injected into the lithium battery through the injection port 1, so that the lithium battery can continue to be used.

[0055] The lithium battery provided in this embodiment has a stable connection between the assembled plastic part 20 and the shell 10, which can ensure that the connecting piece is firmly placed, avoid the occurrence of lithium battery short circuit problems caused by deformation of the tab, and have a high overall safety factor during use.

[0056] Obviously, the above-described embodiments of the present invention are merely examples for the purpose of clearly illustrating the present invention and are not intended to limit the manner in which the present invention is to be implemented. A person skilled in the art would be able to make various obvious changes, readjustments, and substitutions without departing from the scope of protection of the present invention. It is not necessary and impossible to enumerate all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the claims of the present invention.

Claims

1. A battery housing, characterized in that: include: A housing (10), the housing (10) being used to house the battery core, and the housing (10) being provided with a through hole (11); The combined plastic part (20) comprises a first plastic part (21) and a second plastic part (22), wherein the first plastic part (21) is a flat plate structure, the first plastic part (21) is bonded to a side of the housing (10) provided with the through hole (11), the second plastic part (22) is bonded to the first plastic part (21), the first plastic part (21) is provided with a first through hole (211) corresponding to the through hole (11), and the second plastic part (22) is provided with a second through hole (211) corresponding to the first through hole (211). 21), a peripheral portion (222) is provided on a side of the second plastic part (22) that is in contact with the first plastic part (21), the peripheral portion (222) is arranged around the second through hole (221), the peripheral portion (222) can pass through the first through hole (211) and be inserted into the through hole (11) and interference fit with the through hole (11); a receiving groove (223) is provided on a side of the second plastic part (22) that is away from the peripheral portion (222), and the receiving groove (223) is used to place a connecting piece.

2. The battery case according to claim 1, wherein: The combined plastic part (20) comprises two second plastic parts (22), and the two second plastic parts (22) are spaced apart from the first plastic part (21).

3. The battery case according to claim 1, wherein: The accommodating groove (223) is arranged parallel to the second through hole (221).

4. The battery case according to claim 1, wherein: The thickness of the combined plastic part (20) is 1 mm to 10 mm.

5. The battery case according to claim 1, wherein: The outer wall of the peripheral portion (222) is provided with an interference rib (30); and / or the inner wall of the through hole (11) is provided with an interference rib (30).

6. The battery case according to claim 5, characterized in that The top surface or bottom surface of the interference rib (30) is provided with a chamfer.

7. The battery case according to claim 5, characterized in that There are a plurality of interference ribs (30), and the plurality of interference ribs (30) are spaced apart on the outer wall of the peripheral portion (222); or, the plurality of interference ribs (30) are spaced apart on the inner wall of the through hole (11).

8. The battery case according to claim 7, characterized in that The through hole (11) is a strip-shaped hole, and the inner wall of the through hole (11) along the length direction is provided with at least two of the interference ribs (30), and the inner wall of the through hole (11) along the width direction is provided with at least one of the interference ribs (30); or, the side wall of the peripheral portion (222) along the length direction is provided with at least two of the interference ribs (30), and the side wall of the peripheral portion (222) along the width direction is provided with at least one of the interference ribs (30).

9. The battery casing according to any one of claims 1 to 8, characterized in that: The battery housing further comprises an explosion-proof valve (40), and the explosion-proof valve (40) is arranged on the housing (10).

10. A lithium battery comprising a battery cell and a connecting piece, characterized in that: The lithium battery further comprises a battery casing as claimed in any one of claims 1 to 9, the battery cell is placed in the casing (10), the connecting piece is placed in the receiving groove (223) of the second plastic part (22), and the tab on the battery cell passes through the through hole (11), the first through hole (211) and the second through hole (221) and is connected to the connecting piece.

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