Battery cell shell, battery cell and battery pack

Abstract

The utility model relates to the technical field of power batteries, in particular to a battery cell shell, a battery cell and a battery pack. The battery cell shell comprises a shell and a first plastic part, the shell comprises a shell main body and a cover plate, the shell main body is provided with an opening, the cover plate is arranged at the opening, and a first lug hole is formed in the cover plate; the first plastic part is arranged on the side, away from the shell body, of the cover plate, a second lug hole is formed in the first plastic part, the hole wall of the second lug hole extends towards the cover plate to form a connecting ring, the connecting ring extends into the first lug hole and is in interference fit with the cover plate, and a lug shaping unit is arranged on the side face, away from the cover plate, of the second plastic part. The connecting ring of the first plastic part extends into the first lug hole and is in interference connection with the cover plate, so that the manufacturing precision required by interference connection is greatly reduced, and the processing and manufacturing cost of the battery cell shell can be reduced. The tab shaping unit can make the shape of the folded tabs better, protect the tabs and prevent short circuit between the tabs and the energized core shell caused by poor tab folding shape.

Description

Technical Field

[0001] The utility model relates to the technical field of power batteries, and in particular to a battery cell shell, a battery cell and a battery pack. Background Art

[0002] Currently, lithium-ion batteries are widely used in automobiles and energy storage systems. The cost and safety of battery cell structural components are mainly concentrated in the battery cover, which accounts for a large cost of the battery cell structural components. Due to its complex structure, the battery cover has high requirements for process stability, which affects the safety of the battery cell.

[0003] In the prior art, to securely connect the upper plastic part to the cover plate, rivets are used to connect the two. However, these rivets require high positioning, resulting in increased machining precision and increased costs for the cell housing. Furthermore, to improve space utilization within the cell housing, tab holes are provided in the cell housing for the tabs to pass through. After being folded, the tabs pass through the tab holes. However, poorly shaped tabs after folding can cause short circuits.

[0004] Therefore, there is an urgent need for a battery cell shell to solve the above technical problems. Utility Model Content

[0005] The purpose of the present invention is to provide a battery cell shell, a battery cell and a battery pack, which can reduce the processing and manufacturing cost of the battery cell shell and avoid a short circuit between the tab and the shell caused by a poor tab folding shape.

[0006] To achieve this purpose, the present invention adopts the following technical solutions:

[0007] In a first aspect, a battery cell housing is provided, comprising:

[0008] A housing, the housing comprising a housing body and a cover plate, the housing body having an opening, the cover plate being disposed at the opening;

[0009] a first plastic part, disposed on a side of the cover plate facing away from the shell body, the cover plate being interference-connected to the first plastic part;

[0010] The second plastic part is arranged on a side of the cover plate facing the shell body, and a tab shaping unit is arranged on a side of the second plastic part facing away from the cover plate.

[0011] As a preferred technical solution for the above-mentioned battery cell shell, the cover plate is provided with a first pole lug hole, and the first plastic part is provided with a second pole lug hole. The first pole lug hole and the second pole lug hole can allow the pole lug to pass through the battery cell shell. The first pole lug hole and the second pole lug hole are arranged opposite to each other. Among the first pole lug hole and the second pole lug hole, the hole wall of one of them is provided with a connecting ring, and the connecting ring extends into the other with an interference fit.

[0012] As a preferred technical solution of the above-mentioned battery cell housing, the outer peripheral wall of the connecting ring is provided with an interference rib, and the interference rib is abutted against the hole wall of the first pole ear hole.

[0013] As a preferred technical solution of the above-mentioned battery cell housing, the length direction of the interference rib is in the same direction as the height direction of the connecting ring; and / or,

[0014] The length direction of the interference rib is arranged at an angle to the height direction of the connecting ring; and / or,

[0015] The length extension direction of the interference rib is in the same direction as the length direction of the connecting ring.

[0016] As a preferred technical solution of the above-mentioned battery cell shell, the interference ribs are vertical strip protrusions, wave-shaped protrusions, inclined strip protrusions, horizontal strip protrusions, arc-shaped protrusions and / or columnar protrusions.

[0017] As a preferred technical solution of the above-mentioned battery cell housing, the interference ribs are provided on two long side walls of the connecting ring that are away from each other; or,

[0018] The edge of the interference rib has a chamfer; or,

[0019] The thickness of the interference rib ranges from 0.05 mm to 0.3 mm.

[0020] As an optimal technical solution for the above-mentioned battery cell shell, the battery cell shell also includes a second plastic part, which is arranged on the side of the cover plate away from the first plastic part, and the second plastic part is provided with a third pole lug hole for the pole lug to extend out, and a pole lug shaping unit is provided on the side of the second plastic part away from the cover plate, and the pole lug shaping unit is arranged on the side of the third pole lug hole.

[0021] As an optimal technical solution for the above-mentioned battery cell shell, the tab shaping unit includes a guide surface, which is arranged on both sides of the third tab hole. From the third tab hole toward the long side wall of the second plastic part, the guide surface gradually moves away from the cover plate.

[0022] In a second aspect, a battery cell is provided, comprising a core pack and a battery cell shell according to any of the above schemes, wherein the core pack is arranged in a cavity formed by the battery cell shell.

[0023] In a third aspect, a battery pack is provided, comprising a box and the battery cell described in the above scheme, wherein the battery cell is arranged in the box.

[0024] The utility model has at least the following beneficial effects:

[0025] The battery cell housing provided by the utility model has an interference fit connection between the first plastic part and the cover plate. Compared with the prior art, the manufacturing precision required for the interference fit connection is significantly reduced, thereby reducing the processing and manufacturing costs of the battery cell housing. The tab shaping unit acts to limit and fix the tab, thereby improving the tab's shape after folding, protecting the tab and preventing the tab from shorting with the battery cell housing due to poor folding shape.

[0026] The present invention also provides a battery cell, comprising a core pack and a battery cell housing provided by the present invention, wherein the core pack is disposed within a cavity formed by the battery cell housing. Due to the interference fit between the first plastic part and the cover plate, the manufacturing precision required for the interference fit is significantly reduced compared to the prior art, thereby reducing the processing and manufacturing costs of the battery cell housing. The tab shaping unit serves to position and fix the tab, thereby achieving a better shape after the tab is folded, protecting the tab and preventing a short circuit between the tab and the battery cell housing due to poor tab folding.

[0027] The present invention also provides a battery pack comprising a housing and a battery cell provided by the present invention, wherein the battery cell is disposed within the housing. Due to the interference fit between the first plastic part and the cover plate, the manufacturing precision required for the interference fit is significantly reduced compared to the prior art, thereby reducing the processing and manufacturing costs of the battery cell housing. The tab shaping unit serves to position and fix the tab, thereby achieving a better shape after the tab is folded, protecting the tab and preventing a short circuit between the tab and the battery cell housing caused by poorly folded tab shape. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following is a brief introduction to the drawings required for use in the description of the embodiments of the present invention. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the contents of the embodiments of the present invention and these drawings without paying any creative work.

[0029] Figure 1 A schematic diagram of the structure of a battery cell housing provided in an embodiment of the present utility model;

[0030] Figure 2 An exploded schematic diagram of a battery cell housing provided by an embodiment of the present utility model;

[0031] Figure 3 A top view of a battery cell housing provided in an embodiment of the present utility model;

[0032] Figure 4 for Figure 3 Cross-sectional view at AA in the middle;

[0033] Figure 5 for Figure 4 Cross-sectional view at the middle BB;

[0034] Figure 6 for Figure 5 Cross-sectional view at CC;

[0035] Figure 7 A schematic diagram of a second plastic part provided in an embodiment of the present utility model;

[0036] Figure 8 A schematic diagram of a first plastic part provided in an embodiment of the present utility model;

[0037] Figure 9 for Figure 6 A partial enlarged view of point D in the middle.

[0038] In the picture:

[0039] 1. Shell; 11. Shell body; 12. Cover plate; 121. First pole lug hole; 122. Groove; 123. Liquid injection hole; 2. First plastic part; 21. Second pole lug hole; 22. Connecting ring; 23. Interference rib; 3. Second plastic part; 31. Third pole lug hole; 32. Pole lug shaping unit; 321. Guide surface; 33. Long side wall; 4. Explosion-proof valve. DETAILED DESCRIPTION

[0040] 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.

[0041] 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.

[0042] 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.

[0043] 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.

[0044] like Figure 1-8 As shown, an embodiment of the present invention provides a battery cell shell, which can reduce the processing accuracy requirements for the battery cell shell and thus reduce the manufacturing cost.

[0045] like Figure 1 and Figure 2 As shown, the battery cell housing includes a shell 1, a first plastic part 2, and a second plastic part 3. The shell 1 includes a shell body 11 and a cover plate 12. The shell body 11 has an opening, and the cover plate 12 is arranged at the opening. The first plastic part 2 is arranged on the side of the cover plate 12 facing away from the shell body 11, wherein the cover plate 12 and the first plastic part 2 are interference-connected. The second plastic part 3 is arranged on the side of the cover plate 12 facing the shell body 11, and the side of the second plastic part 3 facing away from the cover plate 12 is provided with a tab shaping unit 32.

[0046] The battery cell housing provided by the present invention significantly reduces the manufacturing precision required for interference fit compared to the prior art due to the interference fit between the first plastic part 2 and the cover plate 12, thereby reducing the processing and manufacturing costs of the battery cell housing. The tab shaping unit 32 serves to limit and fix the tab, thereby improving the tab's shape after folding, protecting the tab and preventing a short circuit between the tab and the battery cell housing caused by poorly folded tab shape.

[0047] Specifically, the cover plate 12 defines a first tab hole 121, and the first plastic part 2 defines a second tab hole 21. The tab passes through the first and second tab holes 121, 21, and then connects to the terminal post. This reduces the overall height of the battery cell housing and improves internal space utilization. A connecting ring 22 extends from the wall of one of the first tab hole 121 and the second tab hole 21, extending into the other with an interference fit. The provision of the connecting ring 22 ensures an interference fit between the first plastic part 2 and the cover plate 12.

[0048] Illustratively, a connecting ring 22 extends from the hole wall of the second tab hole 21 toward the first tab hole 121 , and the connecting ring 22 extends into the second tab hole 21 with an interference fit, thereby achieving interference connection between the first plastic part 2 and the cover plate 12 .

[0049] In some embodiments, to facilitate installation, such as Figure 3-5 and Figure 8 As shown, the outer peripheral wall of the connecting ring 22 is provided with interference ribs 23, which abut against the wall of the first tab hole 121. The number of interference ribs 23 can be one or more, as long as the first plastic part 2 and the cover plate 12 can be interference-connected. Of course, in other embodiments, the connecting ring 22 can be larger than the first tab hole 121, have the same cross-sectional shape as the first tab, and be able to be inserted into the first tab hole 121.

[0050] In some embodiments, the length direction of the interference rib 23 is in the same direction as the height direction of the connecting ring 22 , which can facilitate demoulding and also achieve a more secure connection between the first plastic part 2 and the cover plate 12 .

[0051] In some other embodiments, the length direction of the interference rib 23 is set at an angle to the height direction of the connecting ring 22, that is, the length direction of the interference rib 23 is not parallel to the height direction of the connecting ring 22. Such a setting can achieve a stable connection between the first plastic part 2 and the cover plate 12.

[0052] In some other embodiments, the length direction of the interference rib 23 is the same as the length direction of the connecting ring 22 , that is, the length direction of the interference rib 23 is parallel to the cover plate 12 .

[0053] In some embodiments, the interference ribs 23 are vertical strip protrusions, corrugated protrusions, inclined strip protrusions, horizontal strip protrusions, arc-shaped protrusions and / or columnar protrusions, wherein there are multiple protrusions, so that the first plastic part 2 and the cover plate 12 can be interference connected.

[0054] In some embodiments, interference ribs 23 are provided on two long side walls 33 that are opposite to each other in the connecting ring 22. Since the first tab hole 121 is an elongated hole, the connecting ring 22 has the same shape as the first tab hole 121. Interference ribs 23 are provided on two long side walls 33 that are opposite to each other in the connecting ring 22. In this way, multiple interference ribs 23 can be provided, thereby increasing the friction between the connecting ring 22 and the cover plate 12, and making the connection between the first plastic part 2 and the cover plate 12 more stable.

[0055] In some embodiments, the edge of the interference rib 23 has a chamfer; preferably, the chamfer is an oblique angle, which can serve as a guide and facilitate assembly.

[0056] In some embodiments, the thickness of the interference rib 23 ranges from 0.05 mm to 0.3 mm. Alternatively, the thickness of the interference rib 23 can be 0.05 mm, 0.1 mm, 0.15 mm, 0.2 mm, 0.25 mm, or 0.3 mm, without specific limitation. A thickness of 0.05 mm prevents excessive thickness of the interference rib 23 from preventing assembly, while a thickness of 0.3 mm prevents insufficient thickness from preventing secure fixation.

[0057] In the related art, the tabs are connected to the connecting pieces after being folded, and the connecting pieces are connected to the poles, thereby achieving the purpose of connecting the tabs to the poles. However, the tabs have a poor shape after being folded, which can easily cause a short circuit. Therefore, in some embodiments, such as Figure 4-Figure 7 As shown, the cell housing further includes a second plastic part 3, which is disposed on the side of the cover plate 12 facing away from the first plastic part 2. The second plastic part 3 is provided with a third tab hole 31 for the tab to extend out, and a tab shaping unit 32 is disposed on the side of the second tab hole 21. The tab shaping unit 32 serves to limit and fix the tab, thereby making the tab have a better shape after being folded, protecting the tab, and preventing the tab from short-circuiting with the cover plate due to poor tab folding shape.

[0058] Specifically, the number of the tab shaping units 32 and the number of the second tab holes 21 are arranged in a one-to-one correspondence, that is, the tab shaping unit 32 can be single or multiple.

[0059] Furthermore, if Figure 6 and Figure 7 As shown, the tab shaping unit 32 includes guide surfaces 321, which are provided on both sides of the third tab hole 31. The extension direction of the guide surfaces 321 is the same as the longitudinal extension direction of the third tab hole 31. From the third tab hole 31 toward the long sidewall 33 of the second plastic part 3, the guide surfaces 321 gradually move away from the second plastic part 3. In other words, the guide surfaces 321 are arranged at an angle relative to the second plastic part 3. The guide surfaces 321 provide guidance for the tabs and, after the tabs are folded, always limit and press the tabs, thereby keeping the tabs in a folded state and preventing the tabs from separating.

[0060] The tab passes through the third tab hole 31 , the first tab hole 121 and the second tab hole 21 and is folded over the first plastic part 2 , which can improve the internal space utilization of the battery cell. Compared with the prior art, the internal space utilization of the battery cell can be improved.

[0061] If only positive electrode posts or negative electrode posts are designed on the cover plate 12, the number N of the first tab holes 121 is ≥1. If positive electrode posts and negative electrode posts are arranged at intervals on the side of the cover plate 12 facing the first plastic part 2, the number of first tab holes 121 corresponding to the positive electrode posts and the negative electrode posts is ≥1, and the tabs pass through the first tab holes 121 and are folded over the cover plate 12, which can improve the internal space utilization of the battery.

[0062] In some embodiments, the first plastic part 2 is a split structure, which is easy to manufacture.

[0063] And / or, in some embodiments, the second plastic part 3 is a split structure, which is easy to manufacture.

[0064] And / or, in some embodiments, the first plastic part 2 is an integrally formed structure, which is convenient for subsequent assembly and installation, and the second tab hole 21 is simultaneously formed during the injection molding process, which is convenient for subsequent assembly and installation.

[0065] And / or, in some embodiments, the second plastic part 3 is an integrally formed structure, and the third tab hole 31 and the tab shaping unit 32 are formed simultaneously during the injection molding process, which facilitates subsequent assembly and installation.

[0066] In some embodiments, as Figure 9 As shown, the cover plate 12 is provided with a groove 122, and the first plastic part 2 is located within the groove 122. The provision of the groove 122 prevents the first plastic part 2 from protruding too much, thereby increasing the overall height of the cover plate 12 and improving volume utilization. Specifically, the distance between the surface of the flange of the first plastic part 2 facing away from the groove 122 and the surface of the cover plate 12 facing away from the second plastic part 3 is h, where -0.5H≤h≤H, and the thickness of the cover plate 12 is H. Exemplarily, the distance h is -0.5H, -0.4H, -0.3H, -0.2H, -0.1H, 0, 0.1H, 0.2H, 0.3H, 0.3H, 0.4H, 0.5H, 0.6H, 0.7H, 0.8H, 0.9H, or H, which is not specifically limited here.

[0067] When the distance between the surface of the first plastic part 2 facing away from the groove 122 and the surface of the cover plate 12 facing away from the second plastic part 3 is -0.5H, the surface of the first plastic part 2 facing away from the groove 122 is located within the groove 122 and does not protrude from the groove 122, thereby improving volume utilization. Furthermore, when the distance between the surface of the first plastic part 2 facing away from the groove 122 and the surface of the cover plate 12 facing away from the second plastic part 3 is H, the cover plate can be prevented from having low strength.

[0068] In some embodiments, the first plastic part 2 has a flange with a width L, where 0 < L < 10 mm. For example, L can be 1 mm, 2 mm, 3 mm, 4 mm, 5 mm, 6 mm, 7 mm, 8 mm, 9 mm, or 10 mm, without specific limitation. This configuration avoids the risk of an excessively large flange causing increased weight, material, and cost of the first plastic part 2, which could affect the housing design.

[0069] In some embodiments, the cover plate 12 is further provided with an explosion-proof valve 4 and / or a liquid injection hole 123. The explosion-proof valve 4 is formed by a notch provided on the cover plate 12. The notch can be provided on the inner side of the cover plate 12 (the side facing the second plastic part 3) or the outer side (the side facing the first plastic part 2). The liquid injection hole 123 can be provided near the positive electrode column, near the negative electrode column, or between the positive and negative electrode columns.

[0070] The present invention also provides a battery cell, comprising a core pack and a battery cell housing provided by the present invention, wherein the core pack is disposed within a cavity formed by the battery cell housing. Due to the interference fit between the first plastic part 2 and the cover plate 12, the manufacturing precision required for the interference fit is significantly reduced compared to the prior art, thereby reducing the processing and manufacturing costs of the battery cell housing.

[0071] Specifically, a connecting ring 22 is provided on the side of the first plastic part 2 of the battery cell shell facing the cover plate 12. The connecting ring 22 extends into the first pole ear hole 121 and is interference connected with the cover plate 12. Compared with the existing technology, the manufacturing precision required for the interference connection is greatly reduced, which can reduce the processing and manufacturing cost of the battery cell.

[0072] For example, the first plastic part 2 and the second plastic part 3 are both plastic plates.

[0073] The present invention also provides a battery pack comprising a housing and a battery cell provided by the present invention, wherein the battery cell is disposed within the housing. Due to the interference fit between the first plastic part 2 and the cover plate 12, the manufacturing precision required for the interference fit is significantly reduced compared to the prior art, thereby reducing the processing and manufacturing costs of the battery cell housing.

[0074] Specifically, a connecting ring 22 is provided on the side of the first plastic part 2 of the battery cell shell facing the cover plate 12. The connecting ring 22 extends into the first pole ear hole 121 and is interference connected with the cover plate 12. Compared with the existing technology, the manufacturing precision required for the interference connection is greatly reduced, which can reduce the processing and manufacturing cost of the battery pack.

[0075] Furthermore, the above are merely preferred embodiments of the present invention and the technical principles employed. Those skilled in the art will appreciate that the present invention is not limited to the specific embodiments described herein, and that various obvious changes, readjustments, and substitutions are possible for those skilled in the art without departing from the scope of protection of the present invention. Therefore, although the present invention has been described in detail through the above embodiments, the present invention is not limited to the above embodiments and may include many other equivalent embodiments without departing from the scope of the present invention. The scope of the present invention is determined by the scope of the appended claims.

Claims

1. A battery cell shell, characterized in that: include: A housing (1), the housing (1) comprising a housing body (11) and a cover plate (12), the housing body (11) having an opening, and the cover plate (12) being arranged at the opening; A first plastic part (2) is arranged on a side of the cover plate (12) facing away from the shell body (11), and the cover plate (12) and the first plastic part (2) are interference-connected; The second plastic part (3) is provided on the side of the cover plate (12) facing the shell body (11), and a tab shaping unit (32) is provided on the side of the second plastic part (3) facing away from the cover plate (12).

2. The battery cell housing according to claim 1, wherein: The cover plate (12) is provided with a first pole ear hole (121), and the first plastic part (2) is provided with a second pole ear hole (21). The first pole ear hole (121) and the second pole ear hole (21) can allow the pole ear to pass through the battery cell shell. The first pole ear hole (121) and the second pole ear hole (21) are arranged opposite to each other. A connecting ring (22) is provided on the hole wall of one of the first pole ear hole (121) and the second pole ear hole (21), and the connecting ring (22) extends into the other with an interference fit.

3. The battery cell shell according to claim 2, characterized in that: The outer peripheral wall of the connecting ring (22) is provided with an interference rib (23), and the interference rib (23) abuts against the hole wall of the first pole lug hole (121).

4. The battery cell housing according to claim 3, wherein: The length direction of the interference rib (23) is in the same direction as the height direction of the connecting ring (22); and / or, The length direction of the interference rib (23) is arranged at an angle to the height direction of the connecting ring (22); and / or, The length extension direction of the interference rib (23) is in the same direction as the length direction of the connecting ring (22).

5. The battery cell casing according to claim 3, characterized in that: The interference ribs (23) are arranged on two long side walls (33) of the connecting ring (22) that are away from each other.

6. The battery cell casing according to claim 3, characterized in that: The interference rib (23) is a vertical strip protrusion, a wave-shaped protrusion, an inclined strip protrusion, a horizontal strip protrusion, an arc-shaped protrusion and / or a columnar protrusion; or, The edge of the interference rib (23) has a chamfer; or, The thickness of the interference rib (23) ranges from 0.05 mm to 0.3 mm.

7. The battery cell casing according to claim 1, characterized in that: The battery cell shell further comprises a second plastic part (3), the second plastic part (3) being arranged on a side of the cover plate (12) facing away from the first plastic part (2), the second plastic part (3) being provided with a third pole lug hole (31) for the pole lug to extend out, and the pole lug shaping unit (32) being arranged on the side of the third pole lug hole (31).

8. The battery cell casing according to claim 7, characterized in that: The tab shaping unit (32) includes guide surfaces (321), which are arranged on both sides of the third tab hole (31). From the third tab hole (31) toward the long side wall (33) of the second plastic part (3), the guide surfaces (321) gradually move away from the cover plate (12).

9. A battery cell, characterized in that: The battery cell shell comprises a core pack and the battery cell shell according to any one of claims 1 to 8, wherein the core pack is arranged in a cavity formed by the battery cell shell.

10. A battery pack, characterized in that: The invention comprises a box body and the battery cell according to claim 9, wherein the battery cell is arranged in the box body.

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