Battery cell and battery pack

Abstract

The invention relates to the technical field of batteries, in particular to a battery cell and a battery pack. The battery cell comprises: a housing having an opening; the pole group is arranged in the shell through the opening, one end of the pole group, which firstly enters the shell, is a first end, and one end of the pole group, which then enters the shell, is a second end along the direction of the pole group entering the shell; the insulating component coats the circumferential side wall of the pole group, and enters the shell together with the pole group; one side, wrapping the first end, of the insulation assembly is provided with a protruding part extending outwards, and the protruding part enters the shell before the pole group. Compared with the prior art, the convex part on the insulation assembly enters the shell before the pole group, so that the traction effect on the pole group entering the shell is achieved, the situation that a hot melting area on the insulation assembly is damaged due to wrinkle accumulation of the insulation assembly is avoided, the insulation protection capability of the insulation assembly is guaranteed, the shell entering efficiency and the shell entering yield of the pole group are improved to a certain degree, and the product quality is improved. And the production efficiency and the production quality of the battery cell and the battery pack are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of batteries, and more particularly to a battery cell and a battery pack. Background Art

[0002] Lithium-ion batteries are currently widely used in fields such as transportation power sources, power energy storage power sources, new energy storage power sources, and aerospace and military industries due to their advantages of large capacity, high working voltage, strong charge retention ability, and long cycle life.

[0003] A battery cell is the smallest unit of a lithium battery pack. Currently, a battery cell includes structures such as a pole group, an electrolyte, a bare battery cell insulating sheet, a cover plate, and a housing. Among them, the housing and the cover plate are fixedly connected by welding to form a closed space for accommodating the pole group; the bare battery cell insulating sheet is wrapped outside the pole group to play roles such as electrical insulation and protecting the pole group from being damaged by the housing weld seam. After the bare battery cell insulating sheet is heat-melted and fixed with the lower plastic of the cover plate, during the subsequent process of inserting the pole group into the housing, the pole group is inserted into the housing by moving the housing towards the pole group. Since the distance between the outer wall of the pole group and the inner wall of the housing is limited, as the insertion depth into the housing increases, the friction between the pole group and the housing gradually increases. In the length direction of the battery cell, wrinkles and accumulations often occur at the heat-melt welding position of the bare battery cell insulating sheet and the cover plate, and then the problem of rupture occurs, seriously affecting the process yield, and thus affecting the production efficiency and production quality of the battery cell and the battery pack. Summary of the Invention

[0004] In view of this, the purpose of this application is to provide a battery cell and a battery pack to solve the problem that in the housing insertion process of the existing battery cell during assembly, as the insertion depth of the pole group into the housing increases, the bare battery cell insulating sheet is prone to wrinkle accumulation and even rupture, affecting the production efficiency and production quality of the battery cell and the battery pack.

[0005] The first aspect of the present invention provides a battery cell, wherein the battery cell includes: A housing having an opening; A pole group inserted into the housing through the opening. Along the direction in which the pole group enters the housing, the end of the pole group that first enters the housing is the first end, and the end that enters the housing later is the second end; An insulating assembly covering the circumferential side wall of the pole group and entering the housing together with the pole group; a convex portion extending outward is formed on one side of the insulating assembly covering the first end, and the convex portion enters the housing before the pole group.

[0006] Preferably, the opening includes an inlet portion and an outlet portion. By pulling the convex portion from the outlet portion, the pole group and the insulating assembly enter the housing through the inlet portion, the pole group remains in the housing, and the convex portion extends out from the outlet portion.

[0007] Preferably, after all the electrode groups enter the housing, the convex portion is cut off from the insulation assembly.

[0008] Preferably, the convex portion is formed as a strip structure extending along the direction in which the electrode group enters the housing.

[0009] Preferably, the insulation assembly includes a large surface side and a narrow surface side, and the large surface side and the narrow surface side alternately surround the circumferential side wall of the electrode group, and the convex portion is provided on the large surface side.

[0010] Preferably, the size of the large surface side in the width direction of the electrode group is W1, in millimeters; the size of the convex portion in the width direction of the electrode group is W2, in millimeters; W2≥1 / 3W1; And / or, the size of the convex portion in the length direction of the electrode group is L, 30mm≤L≤50mm.

[0011] Preferably, the insulation assembly includes: A first insulation member, covering the circumferential side wall of the electrode group, and the convex portion extends outward from the first insulation member; Side plates, clamped between the first insulation member and the electrode group.

[0012] Preferably, the battery cell further includes: A cover plate assembly, connected to the insulation assembly, and when the convex portion enters the housing, the cover plate assembly moves synchronously with the convex portion.

[0013] Preferably, the cover plate assembly includes: A cover plate main body, connected to the housing; A second insulation member, disposed on a side of the cover plate main body facing the insulation assembly, and the second insulation member and the insulation assembly are heat-melted and connected.

[0014] In a second aspect of the present invention, a battery pack is provided, including the battery cell according to any one of the above technical solutions.

[0015] Compared with the prior art, the beneficial effects of the present invention are as follows: The battery cell of the present invention includes a housing, an electrode group, and an insulation assembly. The insulation assembly covers the circumferential side wall of the electrode group and enters the housing together with the electrode group. A convex portion extending outward is formed on one side of the insulation assembly covering the first end of the electrode group that enters the housing first. The convex portion enters the housing before the electrode group, so as to play a role in pulling the electrode group into the housing, avoid the damage of the heat-melted area on the insulation assembly caused by the folding and accumulation of the insulation assembly, ensure the insulation protection ability of the insulation assembly, and to a certain extent improve the efficiency and yield of the electrode group entering the housing, and improve the production efficiency and production quality of the battery cell and the battery pack.

[0016] To make the above objects, features, and advantages of the present application more obvious and understandable, the following provides preferred embodiments in conjunction with the accompanying drawings and detailed descriptions are as follows. Description of the Drawings

[0017] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings required for use in the description of the specific embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0018] Figure 1 Explosion structure schematic diagram of the battery cell provided by the embodiment of the present invention; Figure 2 Structure schematic diagram of the insulation component in the battery cell provided by the embodiment of the present invention; Figure 3 Structure schematic diagram of the insulation component covering the electrode group in the battery cell provided by the embodiment of the present invention.

[0019] Reference numerals: 10 - housing; 11 - inlet part; 12 - outlet part; 20 - electrode group; 201 - first end; 202 - second end; 30 - insulation component; 31 - first insulation member; 301 - large surface side; 302 - narrow surface side; 311 - convex part; 32 - side plate; 40 - cover plate assembly; 41 - cover plate main body; 42 - second insulation member; 50 - end plate. Specific Embodiments

[0020] The following specific embodiments are provided to help readers obtain a comprehensive understanding of the methods, devices, and / or systems described herein. However, after understanding the disclosure of the present application, various changes, modifications, and equivalents of the methods, devices, and / or systems described herein will be obvious. For example, the order of operations described herein is merely illustrative and is not limited to the order set forth herein. Rather, changes that will be obvious after understanding the disclosure of the present application can be made, except for operations that must occur in a specific order. In addition, for the sake of clarity and conciseness, descriptions of features known in the art may be omitted.

[0021] The features described herein may be implemented in different forms and should not be construed as limited to the examples described herein. Rather, the examples described herein are provided only to illustrate some of the many possible ways of implementing the methods, devices, and / or systems described herein that will be obvious after understanding the disclosure of the present application.

[0022] Throughout the specification, when an element (such as a layer, region, or substrate) is described as being "on" another element, "connected to" another element, "bonded to" another element, "above" another element, or "covering" another element, it can be directly "on" the other element, "connected to" the other element, "bonded to" the other element, "above" the other element, or "covering" the other element, or there can be one or more other elements intervening therebetween. In contrast, when an element is described as being "directly on" another element, "directly connected to" another element, "directly bonded to" another element, "directly above" another element, or "directly covering" another element, there can be no other elements intervening therebetween.

[0023] As used herein, the term "and / or" includes any one of the listed related items and any combination of any two or more of them.

[0024] Although terms such as "first", "second", and "third" may be used herein to describe various components, elements, regions, layers, or parts, these components, elements, regions, layers, or parts are not limited by these terms. Rather, these terms are only used to distinguish one component, element, region, layer, or part from another. Thus, the first component, element, region, layer, or part as referred to in the examples described herein may also be referred to as the second component, element, region, layer, or part without departing from the teachings of the examples.

[0025] For ease of description, spatial relationship terms such as "above", "upper", "below", and "lower" may be used herein to describe the relationship of one element to another as shown in the figures. Such spatial relationship terms are intended to include different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is flipped, an element described as being "above" or "upper" relative to another element will then be located "below" or "lower" relative to the other element. Thus, the term "above" includes both the orientations of "above" and "below" depending on the spatial orientation of the device. The device may also be positioned in other ways (e.g., rotated 90 degrees or in other orientations), and the spatial relationship terms used herein will be interpreted accordingly.

[0026] The terms used herein are for the purpose of describing various examples only and are not intended to limit the present disclosure. Unless the context clearly indicates otherwise, the singular forms are also intended to include the plural forms. The terms "comprising," "including," and "having" enumerate the stated features, quantities, operations, components, elements, and / or combinations thereof that exist, but do not preclude the existence or addition of one or more other features, quantities, operations, components, elements, and / or combinations thereof.

[0027] Due to manufacturing techniques and / or tolerances, variations in the shapes shown in the drawings may occur. Accordingly, the examples described herein are not limited to the specific shapes shown in the drawings, but include changes in shape that occur during manufacturing.

[0028] The features of the examples described herein can be combined in various ways that will be apparent after understanding the disclosure of the present application. In addition, although the examples described herein have various configurations, other configurations are possible, as will be apparent after understanding the disclosure of the present application.

[0029] According to a first aspect of the present invention, a battery cell is provided, which specifically includes a housing 10, an electrode assembly 20, and an insulating assembly 30.

[0030] Hereinafter, the specific structure of the battery cell according to the present embodiment will be described.

[0031] In the present embodiment, as Figure 1 shown, a cavity for containing the electrode assembly 20 is formed inside the housing 10, and the housing 10 has an opening communicating with the cavity. The electrode assembly 20 is inserted into the housing 10 through the opening. Along the direction in which the electrode assembly 20 enters the housing 10, both ends in the length direction of the electrode assembly 20 are formed as a first end 201 and a second end 202. Specifically, the end of the electrode assembly 20 that first enters the housing 10 is the first end 201, and the end that enters the housing 10 later is the second end 202.

[0032] The insulating component 30 is wrapped around the circumferential side wall of the electrode group 20 and enters the housing 10 together with the electrode group 20, so that the insulating component 30 separates the electrode group 20 from the housing 10; a convex portion 311 extending outward is formed on one side of the first end 201 of the insulating component 30 wrapped around the electrode group 20, and the convex portion 311 enters the housing 10 before the electrode group 20. In this way, during the process of the electrode group 20 entering the housing, while the housing 10 moves closer to the electrode group 20, auxiliary tools such as clamping tools can also be used to clamp the convex portion 311, so as to pull the insulating component 30 wrapped with the electrode group 20 in the direction close to the housing 10 to play a traction role, avoiding the damage of the heat-melt area on the insulating component 30 caused by the folding and accumulation of the insulating component 30, ensuring the insulating protection ability of the insulating component 30, and improving the housing efficiency and housing yield of the electrode group 20 to a certain extent, and improving the production efficiency and production quality of the battery cell and the battery pack. The clamping tool can be a clamp such as a jaw or a pair of tweezers.

[0033] Specifically, in this embodiment, as Figure 1 shown, the opening includes an inlet portion 11 and an outlet portion 12. The inlet portion 11 and the outlet portion 12 are disposed opposite to each other on both sides in the length direction of the housing 10. The electrode group 20 wrapped with the insulating component 30 enters the housing through the inlet portion 11, the convex portion 311 first extends into the housing through the inlet portion 11, and the clamping tool clamps the convex portion 311 from the outlet portion 12 and pulls the convex portion 311 in the direction of the electrode group 20 entering the housing 10, so that the electrode group 20 and the insulating component 30 enter the housing 10 through the inlet portion 11 together. After the housing 10 and the electrode group 20 move towards each other to a preset distance, the electrode group 20 remains in the housing 10, while the convex portion 311 extends out of the housing 10 from the outlet portion 12. In this way, the process of the pole entering the housing is completed. While avoiding the damage of the insulating component 30 and ensuring the insulating performance, it is convenient for the electrode group 20 to enter the housing, and the housing efficiency of the electrode group 20 is effectively improved, greatly improving the process yield and production efficiency of the battery cell.

[0034] Further, in this embodiment, after the electrode group 20 completely enters the housing 10 and reaches its required installation position, the convex portion 311 is cut off from the insulating component 30, so as not to affect the subsequent assembly of the battery cell.

[0035] In this embodiment, as Figure 2 and Figure 3 shown, the convex portion 311 is formed into a strip-shaped structure extending in the direction of the electrode group 20 entering the housing 10, such as a rectangular sheet-like structure, so as to facilitate the clamping of the clamping tool and the convex portion 311, and avoid damage to the electrode group 20 by the clamping tool.

[0036] In a preferred embodiment, as Figure 2As shown, the dimension of the convex portion 311 in the length direction of the electrode group 20 is L, and the length dimension of the strip-shaped convex portion 311 is L, where 30 mm ≤ L ≤ 50 mm. In this way, it is effectively ensured that it is convenient for the clamping tooling to clamp the convex portion 311, while avoiding damage to the electrode group 20 by the clamping tooling and avoiding material waste.

[0037] Furthermore, in this embodiment, as Figure 2 and Figure 3 shown, the electrode group 20 is formed into a rectangular block structure. The electrode group 20 can be formed by stacking or winding electrode sheets. The insulating component 30 includes a large surface side 301 and a narrow surface side 302. The area of the large surface side 301 is larger than that of the narrow surface side 302. The large surface side 301 and the narrow surface side 302 alternately surround the circumferential side wall of the electrode group 20. The convex portion 311 is provided on the large surface side 301. In this way, it is ensured that the convex portion 311 has a sufficient width dimension, avoiding the situation of the convex portion 311 breaking during the pulling process, and being more labor-saving. Preferably, the convex portion 311 is provided at the middle position of the large surface side 301 to ensure that the electrode group 20 wrapped with the insulating component 30 is evenly stressed and smoothly enters the housing 10.

[0038] Even further, in this embodiment, as Figure 2 and Figure 3 shown, there are two large surface sides 301, and the convex portion 311 is provided on both of the two large surface sides 301. After the insulating component 30 wraps the electrode group 20, the two convex portions 311 are arranged opposite to each other in the thickness direction of the electrode group 20.

[0039] In a preferred embodiment, as Figure 2 shown, the dimension of the large surface side 301 in the width direction of the electrode group 20 is W1, in mm; the dimension of the convex portion 311 in the width direction of the electrode group 20 is W2, in mm; W2 ≥ 1 / 3W1. In this way, it is ensured that the convex portion 311 has a sufficient width dimension, avoiding the situation of the convex portion 311 breaking due to pulling, so as to ensure the smooth entry of the electrode group 20 into the housing.

[0040] In this embodiment, as Figure 1 and Figure 2 shown, the insulating component 30 includes a first insulating member 31 and a side plate 32; the first insulating member 31 wraps the circumferential side wall of the electrode group 20. The first insulating member 31 can be a bare battery cell insulating sheet, and the convex portion 311 extends outward from the first insulating member 31 and is preferably integrally formed with the first insulating member 31. The side plate 32 is formed into a strip-shaped structure extending along the length direction of the electrode group 20, and the side plate 32 is clamped between the first insulating member 31 and the electrode group 20 to facilitate the integral circumferential wrapping of the electrode group 20 by the first insulating member 31. It should be noted that the above-mentioned large surface side 301 and narrow surface side 302 are both provided on the first insulating member 31.

[0041] In addition, in this embodiment, the battery cell further includes a cover plate assembly 40 connected to the insulation assembly 30. Specifically, two cover plate assemblies 40 are provided to seal the inlet portion 11 and the outlet portion 12 respectively. Before the electrode group 20 is inserted into the housing, the cover plate assembly 40 provided at the inlet portion 11 is connected to the second end 202. When the convex portion 311 enters the housing 10, the cover plate assembly 40 moves synchronously with the convex portion 311. After the electrode group 20 reaches the installation position, the cover plate assembly 40 provided at the second end 202 of the electrode group 20 is fixedly connected to the housing 10 and the convex portion 311 is cut off. Then, the electrode post on the cover plate assembly 40 provided at the first end 201 of the electrode group 20 is welded to the electrode group 20, and then the cover plate assembly 40 provided at the first end 201 of the electrode group 20 is fixed to the housing 10.

[0042] Specifically, in this embodiment, as Figure 1 shown, the cover plate assembly 40 includes a cover plate main body 41 and a second insulating member 42. The cover plate main body 41 is formed into a plate-like structure. The circumferential edge of the cover plate main body 41 is connected to the housing 10 to enclose the housing 10, and the connection method is preferably a welding connection. The second insulating member 42 is disposed on the side of the cover plate main body 41 facing the insulation assembly 30 to provide insulation protection for the cover plate main body 41 and the housing 10, and to prevent short circuits caused by the electrode posts overlapping with each other and the cover plate main body 41 overlapping with the housing 10. The second insulating member 42 and the insulation assembly 30, specifically, the second insulating member 42 is heat-melted and connected to the first insulating member 31. It should be noted that Figure 3 in, the rectangular frame on the first insulating member 31 represents the heat-melted area as described above.

[0043] In addition, in this embodiment, as Figure 1 shown, the battery cell further includes an end plate 50. The end plate 50 is disposed between the electrode group 20 and the cover plate assembly 40 to play a role in supporting and storing the electrolyte. The end plate 50 is disposed on one side in the length direction of the electrode group 20, that is, when two cover plate assemblies 40 are provided, only one of the cover plate assemblies 40 is connected to the end plate 50, and the other cover plate assembly 40 is directly connected to the electrode group 20.

[0044] In a preferred embodiment, the end plate 50 is fixed to the electrode group 20 before the electrode group 20 is inserted into the housing, so as to facilitate assembly.

[0045] According to the present invention, a battery cell is provided. The battery cell includes a housing, an electrode group, and an insulation component. The insulation component is wrapped around the circumferential side wall of the electrode group and enters the housing together with the electrode group. A convex portion extending outward is formed on one side of the first end of the insulation component that wraps around the electrode group and enters the housing first. The convex portion enters the housing before the electrode group, thus playing a role in pulling the electrode group into the housing, avoiding the damage of the heat-melt area on the insulation component caused by the folding and accumulation of the insulation component, ensuring the insulation protection ability of the insulation component, and improving the efficiency and yield of the electrode group entering the housing to a certain extent, as well as improving the production efficiency and quality of the battery cell and the battery pack. In addition, after the electrode group enters the housing, the convex portion is cut off, which does not affect the subsequent assembly.

[0046] According to the present invention, a battery pack is provided, which includes the battery cell as described above, and thus has all the beneficial effects of the battery cell, which will not be elaborated here. The battery pack includes a plurality of battery cells arranged in series and / or in parallel.

[0047] Finally, it should be noted that: the above embodiments are only specific embodiments of the present application, used to illustrate the technical solutions of the present application, rather than limiting them. The protection scope of the present application is not limited thereto. Although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: any person skilled in the art within the technical scope disclosed by the present application can still modify the technical solutions described in the foregoing embodiments, or can easily think of changes, or make equivalent replacements for some of the technical features; and these modifications, changes or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application, and should all be covered within the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A battery cell, characterized in that, The battery cell includes: a housing having an opening; a pole group inserted into the housing through the opening. Along the direction in which the pole group enters the housing, the end of the pole group that first enters the housing is the first end, and the end that later enters the housing is the second end; an insulating assembly covering the circumferential side wall of the pole group and entering the housing together with the pole group; a convex portion extending outward is formed on one side of the insulating assembly covering the first end, and the convex portion enters the housing prior to the pole group.

2. The battery cell according to claim 1, wherein The opening includes an inlet portion and an outlet portion. By pulling the convex portion from the outlet portion, the pole group and the insulating assembly enter the housing through the inlet portion. The pole group remains in the housing, and the convex portion extends out from the outlet portion.

3. The battery cell according to claim 2, wherein, After the entire pole group enters the housing, the convex portion is cut off from the insulating assembly.

4. The battery cell according to claim 1, wherein The convex portion is formed as a strip-shaped structure extending along the direction in which the pole group enters the housing.

5. The battery cell according to claim 1, characterized in that, The insulating assembly includes a large surface side and a narrow surface side, and the large surface side and the narrow surface side alternately surround the circumferential side wall of the pole group. The convex portion is provided on the large surface side.

6. The battery cell according to claim 5, characterized in that, The size of the large surface side in the width direction of the pole group is W1, with the unit of mm; the size of the convex portion in the width direction of the pole group is W2, with the unit of mm; W2 ≥ 1 / 3W1; and / or, the size of the convex portion in the length direction of the pole group is L, and 30 mm ≤ L ≤ 50 mm.

7. The battery cell according to claim 1, wherein The insulating assembly includes: a first insulating member covering the circumferential side wall of the pole group, and the convex portion extends outward from the first insulating member; a side plate clamped between the first insulating member and the pole group.

8. The battery cell according to claim 1, characterized in that, The battery cell further includes: a cover plate assembly connected to the insulating assembly. When the convex portion enters the housing, the cover plate assembly moves synchronously with the convex portion.

9. The cell according to claim 8, wherein, The cover plate assembly includes: a cover plate main body connected to the housing; a second insulating member disposed on the side of the cover plate main body facing the insulating assembly, and the second insulating member and the insulating assembly are heat-melted and connected.

10. A battery pack, characterized in that, A battery cell according to any one of claims 1 to 9.

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