Lithium cell

Abstract

The utility model relates to the technical field of batteries, in particular to a lithium battery cell which comprises a shell and a cover plate, wherein the cover plate covers the opening end of the shell in a sealing mode, a protruding portion is formed on at least one inner side portion of the shell, a buckle is formed on at least one side portion of the cover plate, and the buckle is connected to the protruding portion in a clamped mode. According to the lithium battery cell provided by the invention, the buckles are designed on the side parts of the cover plate, and the cover plate is clamped on the convex parts in the shell by utilizing the buckles, so that the cover plate and the shell are connected more stably, the effect of reinforcing the connection is achieved, the risk that the tabs or the cover plate pops up is avoided, and the lithium battery cell is safer and more reliable; in other words, the risk that the tab is popped out of the cover plate or the cover plate is popped out when the cover plate and the shell are in clearance fit in the prior art is avoided, and meanwhile, the problem that metal wires or metal chips are extruded when the cover plate and the shell are in interference fit in the prior art can also be avoided.

Description

Technical Field

[0001] The present application relates to the field of battery technology, and in particular to a lithium battery cell. Background Art

[0002] At present, with the increasing maturity of lithium-ion battery technology, lithium-ion batteries are widely used as power batteries in electric vehicles and energy storage fields, and the requirements for the performance and safety of lithium-ion batteries are increasing. Lithium batteries are the core components of battery pack safety and assembly, and their structural design is crucial to battery safety. Currently, lithium batteries mostly use a gap fit between the cover plate and the battery shell (about 0.05 on one side), and the tabs often pop out of the cover plate. The negative tab is copper foil, and when there are more layers, there is a risk of the cover plate popping out. If the shell and the cover plate are interference fit, it is easy to have a high pressure into the shell, squeezing out metal wires or metal chips. Therefore, it is currently necessary to develop a lithium battery cell that is safe to fix, has a good fixing effect, and is easy to install. Utility Model Content

[0003] The purpose of the present application is to provide a lithium battery cell, which to a certain extent solves the technical problem in the prior art that a lithium battery cell with safe fixing, good fixing effect and easy installation needs to be developed.

[0004] The present application provides a lithium battery cell, comprising: a shell and a cover plate; wherein the cover plate is sealed on an open end of the shell, a protrusion is formed on at least one inner side of the shell, a buckle is formed on at least one side of the cover plate, and the buckle is snapped onto the protrusion.

[0005] In the above technical solution, further, along the length direction of the cover plate, buckles are formed on the opposite side portions of the cover plate; along the length direction of the shell, protrusions are formed on the opposite inner side portions of the shell; the buckles on the two side portions of the cover plate correspond one-to-one to the protrusions on the two inner side portions of the shell.

[0006] In any of the above technical solutions, further, the cover plate includes a plain aluminum plate and a lower plastic; wherein the lower plastic is installed on the lower surface of the plain aluminum plate; and the buckle is formed on at least one side of the lower plastic.

[0007] In any of the above technical solutions, further, the snap fastener includes a connecting portion, an extending portion and a snap-on protrusion; wherein, the extending portion extends along the height direction of the cover plate, and the top end of the extending portion is connected to the outer side of the lower plastic through the connecting portion, the bottom end of the extending portion is connected to the snap-on protrusion, and the snap-on protrusion is snapped onto the protrusion on the inner side of the shell.

[0008] In any of the above technical solutions, further, along the length direction of the lower plastic, the distance between the extension portion and the corresponding outer side of the lower plastic is L1, and 0.1mm≤L1≤0.5mm.

[0009] In any of the above technical solutions, further, along the length direction of the lower plastic, the size of the extension portion is L2, and 0.4mm≤L2≤1.5mm.

[0010] In any of the above technical solutions, further, along the length direction of the lower plastic, the size of the extension portion is L2, the size of the clamping protrusion is L3, and 0.35mm≤L3-L2≤0.6mm.

[0011] In any of the above technical solutions, further, along the width direction of the lower plastic, the size of the clamping protrusion is W2, and 1.5mm<W2<5mm.

[0012] In any of the above technical solutions, further, along the length direction of the lower plastic, the size of the connecting portion is W1, the size of the clamping protrusion is L3, and W1>L3.

[0013] In any of the above technical solutions, further, the upper surface of the clamping protrusion is inclined downward in a direction away from the extension portion, and the slope of the upper surface of the clamping protrusion is F, and 10°<F<45°

[0014] In any of the above technical solutions, further, the height of the clamping protrusion is H1, and 1mm≤H1≤2mm.

[0015] In any of the above technical solutions, further, the lowest point of the bottom of the clamping protrusion is higher than the lowest point of the bottom of the lower plastic.

[0016] In any of the above technical solutions, further, along the length direction of the plain aluminum plate, the clamping protrusion does not exceed the plain aluminum plate.

[0017] In any of the above technical solutions, further, a groove is formed on the side of the lower plastic, and one end of the connecting portion away from the extending portion is fixed in the groove.

[0018] In any of the above technical solutions, further, the buckle and the lower plastic are an integrated structure, and the material of the integrated structure is an elastic material.

[0019] The material of the integrated structure is polypropylene or polyethylene.

[0020] Compared with the prior art, the beneficial effects of this application are:

[0021] In the lithium battery cell provided in the present application, a clip is designed on the side of the cover plate, and the clip is used to clip on the raised portion inside the shell, thereby realizing the connection between the cover plate and the shell, thereby making the connection between the cover plate and the shell more stable, playing a role in reinforcing the connection, and thus there is no risk of the pole ear or cover plate popping out, and it is safer and more reliable. In other words, it avoids the risk of the pole ear popping out of the cover plate or the cover plate being popped out when the cover plate and the shell are gap-fitted in the prior art, and it can also avoid the problem of extruding metal wire or metal chips when the cover plate and the shell are interference-fitted in the prior art. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the specific implementation methods of the present application or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0023] Figure 1 An exploded view of a cover plate provided in an embodiment of the present application;

[0024] Figure 2 An assembly diagram of a cover plate provided in an embodiment of the present application;

[0025] Figure 3 A schematic diagram of the structure of the lower plastic provided in an embodiment of the present application;

[0026] Figure 4 for Figure 3 A schematic diagram of the enlarged structure at A;

[0027] Figure 5 A cross-sectional view of a cover plate provided in an embodiment of the present application;

[0028] Figure 6 for Figure 5 A partial enlarged schematic diagram of the left end portion;

[0029] Figure 7 for Figure 5 A partial enlarged schematic diagram of the right end portion;

[0030] Figure 8 Another schematic diagram of the structure of the lower plastic provided in the embodiment of the present application;

[0031] Fig. 9 for Figure 8 A partial enlarged schematic diagram of the left end portion;

[0032] Fig.10 for Figure 8 A partial enlarged schematic diagram of the right end portion;

[0033] Fig.11 Another assembly diagram of the cover plate provided in the embodiment of the present application;

[0034] Fig.12 for Fig.11 A partial enlarged schematic diagram of the left end portion;

[0035] Fig.13 A schematic diagram of the structure of a lithium battery cell provided in an embodiment of the present application;

[0036] Fig.14 for Fig.13 A partial enlarged schematic diagram of .

[0037] Reference numerals:

[0038] 1-shell, 11-raised portion, 2-cover plate, 21-plain aluminum plate, 211-horizontal mating surface, 212-vertical mating surface, 22-lower plastic, 23-buckle, 231-connecting portion, 232-extension portion, 233-snapping raised portion, 3-pole group, 4-side plate, 5-Mylar film, 6-upper plastic, 7-riveting block, 8-pole. DETAILED DESCRIPTION

[0039] The technical solution of the present application will be clearly and completely described below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments.

[0040] The components of the embodiments of the present application generally described and shown in the drawings herein can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the application claimed, but merely represents the selected embodiments of the present application.

[0041] Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making any creative work shall fall within the scope of protection of this application.

[0042] In the description of the present application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present application. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0043] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0044] Refer to the following Figures 1 to 14 The lithium battery cell according to some embodiments of the present application is described.

[0045] See also Figures 1 to 4 , Fig.14 As shown, an embodiment of the present application provides a lithium battery cell, comprising: a shell 1 and a cover plate 2; wherein the cover plate 2 is sealed on the open end of the shell 1, a protrusion 11 is formed on at least one inner side of the shell 1, a buckle 23 is formed on at least one side of the cover plate 2, and the buckle 23 is snapped onto the protrusion 11.

[0046] According to the structure described above, it can be known that a buckle 23 is designed on the side of the cover plate 2, and the buckle 23 is used to snap onto the raised portion 11 inside the shell 1, thereby realizing the connection between the cover plate 2 and the shell 1, and thus making the connection between the cover plate 2 and the shell 1 more stable, playing a role in reinforcing the connection, and thus there is no risk of the pole ear or the cover plate 2 popping out, and it is safer and more reliable. In other words, it avoids the risk of the pole ear popping out of the cover plate 2 or the cover plate 2 being popped out when the cover plate 2 and the shell 1 are clearance-fitted in the prior art, and also can avoid the problem of extruding metal wire or metal chips when the cover plate 2 and the shell 1 are interference-fitted in the prior art.

[0047] In this embodiment, preferably, Figure 5 , Figure 6 , Figure 7 and Fig.11 As shown, along the length direction of the cover plate 2, buckles 23 are formed on the opposite sides of the cover plate 2; along the length direction of the shell 1, protrusions 11 are formed on the opposite inner sides of the shell 1; the buckles 23 on the two sides of the cover plate 2 correspond one by one to the protrusions 11 on the two inner sides of the shell 1.

[0048] According to the structure described above, along the length direction of the cover plate 2, the two clips 23 on the two opposite sides of the cover plate 2 are respectively clipped onto the two corresponding raised portions 11 on the two opposite inner sides of the shell 1, which has a better fixing effect and makes the connection between the cover plate 2 and the shell 1 more stable and firm.

[0049] It should be noted that: it is not limited to the aforementioned method of forming the buckles 23 on both sides of the opposite sides of the cover plate 2 along the length direction of the cover plate 2, and the buckle 23 can also be designed on only one side of the cover plate 2 along the length direction of the cover plate 2. In addition, it is not limited to the aforementioned method of designing the buckle 23 on the side of the cover plate 2 along the length direction of the cover plate 2, and the buckle 23 can also be designed on at least one side of the cover plate 2 along the width direction of the cover plate 2, or multiple buckles 23 can be arranged in sequence along the entire circumference of the cover plate 2, etc., and the specific design is based on actual needs.

[0050] In this embodiment, preferably, Figures 1 to 7 As shown, the cover plate 2 includes a plain aluminum plate 21 and a lower plastic 22 ; wherein the lower plastic 22 is installed on the lower surface of the plain aluminum plate 21 ; and a buckle 23 is formed on at least one side of the lower plastic 22 .

[0051] According to the structure described above, the plain aluminum plate 21 is mainly used to cover the open end of the shell 1, and preferably, both sides of the plain aluminum plate 21 along its length direction are provided with matching steps, and this matching step is located on the top of the side wall of the open end of the shell 1 to form a tight fit. In this state, the lower plastic 22 is enclosed in the shell 1, and then a buckle 23 can be designed on the side of the lower plastic 22, so that the buckle 23 can be snap-fitted with the raised portion 11 inside the shell 1, thereby playing a role in strengthening the connection between the cover plate 2 and the shell 1.

[0052] Further, preferably, the mating step includes a horizontal mating surface 211 and a vertical mating surface 212, wherein the horizontal mating surface 211 is mated with the top end surface of the side wall of the shell 1, and the vertical mating surface 212 is mated with the inner wall surface of the shell 1, and preferably, along the length direction of the cover plate 2, the snap-in protrusion 233 described below does not protrude from the vertical mating surface 212, that is, the snap-in protrusion 233 is flush with the vertical mating surface 212 or there is a gap. Of course, it is not limited to this, and is designed according to actual needs. It should be noted that: when the side of the bare aluminum plate 21 does not adopt a mating step structure, that is, when the side of the bare aluminum plate 21 is a vertical plane, the snap-in protrusion 233 does not exceed the bare aluminum plate 21 along the length direction of the bare aluminum plate 21.

[0053] It should be noted that the buckle 23 is not limited to being formed on the lower plastic 22 , but can also be formed on the bare aluminum plate 21 , and is specifically designed according to actual needs.

[0054] In this embodiment, preferably, Figure 4 and Fig.14As shown, the buckle 23 includes a connecting portion 231, an extending portion 232 and a snap-on protrusion 233; wherein the extending portion 232 extends along the height direction of the cover plate 2, and the top end of the extending portion 232 is connected to the side of the lower plastic 22 through the connecting portion 231, and the bottom end of the extending portion 232 is connected to the snap-on protrusion 233, and the snap-on protrusion 233 is snapped onto the protrusion 11 on the inner side of the shell 1.

[0055] According to the structure described above, the connecting portion 231 serves to connect the side of the lower plastic 22 and the extending portion 232, and forms a gap described below between the side of the lower plastic 22 and the extending portion 232, which facilitates assembly; the extending portion 232 is used to make up for the height difference between the protruding portion 11 and the connecting portion 231, so that the clamping protruding portion 233 at the bottom can be clamped on the protruding portion 11.

[0056] Furthermore, preferably, the connecting portion 231 , the extending portion 232 and the snap-fitting protrusion 233 are an integrated structure, which has high overall strength and is not easily damaged, thereby ensuring the stability and firmness of the connection between the cover plate 2 and the shell 1 .

[0057] Further, preferably, the connecting portion 231 extends along a direction perpendicular to the extending portion 232 , and the clamping protrusion 233 protrudes along a direction perpendicular to the extending portion 232 .

[0058] In this embodiment, preferably, Figure 7 As shown, along the length direction of the lower plastic 22 , the distance between the extension portion 232 and the corresponding outer side of the lower plastic 22 is L1 , and 0.1 mm≤L1≤0.5 mm.

[0059] According to the structure described above, a deformation space is reserved between the extension portion 232 and the lower plastic 22 to facilitate the assembly of the buckle 23 and the protrusion 11 .

[0060] In this embodiment, preferably, Figure 7 As shown, along the length direction of the lower plastic 22 , the dimension of the extension portion 232 , for example, the thickness is L2 , and 0.4 mm≤L2≤1.5 mm.

[0061] According to the structure described above, the extension portion 232 is processed according to the aforementioned preset size range, which can not only prevent it from being too thick and not easily deformed, but also ensure that it has a certain strength and is not easily damaged.

[0062] In this embodiment, preferably, Figure 7 As shown, along the length direction of the lower plastic 22 , the dimension of the extension portion 232 , for example, the thickness is L2 , the dimension of the engaging protrusion 233 , for example, the thickness is L3 , and 0.35 mm≤L3-L2≤0.6 mm.

[0063] According to the structure described above, the extension portion 232 is processed according to the aforementioned preset size range, which can ensure that it has sufficient contact area with the raised portion 11 on the inner wall of the shell 1 to ensure the stability and firmness of the snap-on connection, and is not too thick to protrude from the aluminum plate 21 and affect the assembly.

[0064] In this embodiment, preferably, Figure 8 and Fig. 9 As shown, along the width direction of the lower plastic 22 , the dimension of the engaging protrusion 233 is, for example, a length W2 , and 1.5 mm<W2<5 mm.

[0065] According to the structure described above, the width of the snap-fit ​​protrusion 233 is designed according to the above-mentioned size range to ensure that it has sufficient contact area with the protrusion 11 on the inner wall of the shell 1 to ensure the stability and firmness of the snap-fit, and it is not too wide to affect deformation and assembly.

[0066] In this embodiment, preferably, Figure 7 and Fig.10 As shown, along the length direction of the lower plastic 22, the size of the connecting portion 231, for example, the thickness is W1, the size of the snap-fitting protrusion 233, for example, the thickness is L3, and W1>L3, so that the connecting portion 231 and the groove of the lower plastic 22 have sufficient matching length to ensure the stability and firmness of the combination of the connecting portion 231 and the lower plastic 22.

[0067] In this embodiment, preferably, Fig. 9 and Fig.10 As shown, the upper surface of the clamping protrusion 233 is inclined downward in a direction away from the extension portion 232, and relative to the upper surface of the plain aluminum plate 21, the slope of the upper surface of the clamping protrusion 233 is F, and 10°<F<45°.

[0068] According to the structure described above, the upper surface of the snap-fit ​​protrusion 233 is designed as a slope structure, which can play a guiding role when assembled with the protrusion 11 on the inner wall of the shell 1, speed up the assembly speed, and avoid jamming and affecting the assembly problem.

[0069] In this embodiment, preferably, Figure 6 As shown, the lowest point of the bottom of the clamping protrusion 233 is higher than the lowest point of the bottom of the lower plastic 22, so that the lower plastic 22 is supported on the top of the pole group 3, avoiding damage to the clamping protrusion 233 as a force-bearing body.

[0070] In this embodiment, preferably, Figure 6 As shown, the height of the engaging protrusion 233 is H1, and 1mm≤H1≤2mm.

[0071] According to the structure described above, if the clamping protrusion 233 is designed to be too high, it may touch the electrode group 3 and exert pressure on the electrode group 3. If it is designed to be too low, the strength is insufficient. Therefore, the height of the clamping protrusion 233 can be selected within the above range.

[0072] In this embodiment, preferably, the buckle 23 and the lower plastic 22 are an integrated structure, and the material of the integrated structure is elastic material, which is easy to deform and assemble.

[0073] Furthermore, preferably, the material of the integrated structure is polypropylene or polyethylene. Of course, it is not limited thereto, and other elastic materials may also be used.

[0074] Furthermore, preferably, the integrated structure can be realized by injection molding process, which is a mature process and can be mass-produced automatically with high production efficiency.

[0075] It should be noted that: when the buckle 23 and the lower plastic 22 are not an integrated structure, a groove can be formed on the side of the lower plastic 22, and the end of the connecting portion 231 away from the extending portion 232, that is, part of the structure is fixed in the groove, and the connecting portion 231 extends into the groove on the side of the lower plastic 22 to form an interlocking structure, so that the buckle 23 and the lower plastic 22 are more firmly combined.

[0076] In this embodiment, preferably, Figure 1 As shown, the lithium battery cell also includes structures such as an upper plastic 6, a riveting block 7, a pole 8, a pole group 3, a side plate 4 and a Mylar film 5, and the outside of the pole 8 is wrapped with the Mylar film 5, the side of the pole group 3 along its length direction is provided with a side plate 4, and the outside of the pole group 3 and the side plate 4 is wrapped with the Mylar film 5, and the top of the Mylar film 5 extends to the space between the extension portion 232 and the outer portion of the lower plastic 22. This part is the prior art and will not be described in detail here.

[0077] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A lithium battery cell, characterized in that: include: A shell and a cover plate; wherein the cover plate is sealed on the open end of the shell, a protrusion is formed on at least one inner side of the shell, a buckle is formed on at least one side of the cover plate, and the buckle is snap-connected to the protrusion.

2. The lithium battery cell according to claim 1, characterized in that: Along the length direction of the cover plate, buckles are formed on the opposite two sides of the cover plate; along the length direction of the shell, protrusions are formed on the opposite two inner sides of the shell; the buckles on the two sides of the cover plate correspond one by one to the protrusions on the two inner sides of the shell.

3. The lithium battery cell according to claim 1, characterized in that: The cover plate includes a plain aluminum plate and a lower plastic, wherein the lower plastic is installed on the lower surface of the plain aluminum plate; and the buckle is formed on at least one side of the lower plastic.

4. The lithium battery cell according to claim 3, characterized in that: The buckle includes a connecting portion, an extending portion and a snap-on protrusion; wherein the extending portion extends along the height direction of the cover plate, and the top end of the extending portion is connected to the outer side of the lower plastic through the connecting portion, the bottom end of the extending portion is connected to the snap-on protrusion, and the snap-on protrusion is snapped onto the protrusion on the inner side of the shell.

5. The lithium battery cell according to claim 4, characterized in that: Along the length direction of the lower plastic, the distance between the extension portion and the corresponding outer side of the lower plastic is L1, and 0.1mm≤L1≤0.5mm; and / or Along the length direction of the lower plastic, the dimension of the extension portion is L2, and 0.4 mm≤L2≤1.5 mm.

6. The lithium battery cell according to claim 4, characterized in that: Along the length direction of the lower plastic, the dimension of the extension portion is L2, the dimension of the clamping protrusion is L3, and 0.35mm≤L3-L2≤0.6mm; and / or Along the width direction of the lower plastic, the size of the clamping protrusion is W2, and 1.5mm<W2<5mm; and / or Along the length direction of the lower plastic, the size of the connecting portion is W1, the size of the clamping protrusion is L3, and W1>L3.

7. The lithium battery cell according to claim 4, characterized in that: The upper surface of the clamping protrusion is arranged to be inclined downward in a direction away from the extending portion, and the slope of the upper surface of the clamping protrusion is F, and 10°<F<45°; and / or The height of the clamping protrusion is H1, and 1mm≤H1≤2mm.

8. The lithium battery cell according to claim 4, characterized in that: The lowest point of the bottom of the clamping protrusion is higher than the lowest point of the bottom of the lower plastic; and / or Along the length direction of the plain aluminum plate, the clamping protrusion does not extend beyond the plain aluminum plate; and / or A groove is formed on the side of the lower plastic, and one end of the connecting portion away from the extending portion is fixed in the groove.

9. The lithium battery cell according to claim 3, characterized in that: The buckle and the lower plastic are an integrated structure, and the material of the integrated structure is elastic material.

10. The lithium battery cell according to claim 9, characterized in that: The material of the integrated structure is polypropylene or polyethylene.

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