Battery cell, battery module and battery pack

Abstract

The utility model provides a battery cell, a battery module and a battery pack, and relates to the field of battery cell structures. The battery cell comprises a shell provided with an anti-explosion valve group; the pole group is positioned in the shell; and a concave part corresponding to the anti-explosion valve group is formed on one side, facing the anti-explosion valve group, of the pole group. Therefore, when the battery cell is subjected to thermal runaway and the bottom supporting plate is melted down and the pole group sinks, a certain space is still reserved between the pole group and the anti-explosion valve through the concave part, so that high-temperature and high-pressure gas in the battery cell can be smoothly discharged from the anti-explosion valve, and the use safety of the battery cell is ensured.

Description

Technical Field

[0001] This application relates to the field of battery cell structures, and more particularly to a battery cell, a battery module, and a battery pack. Background Art

[0002] Laminated batteries have been favored by major manufacturers due to their high energy density. However, the increase in energy density leads to a corresponding increase in the internal space utilization rate of the battery cell. As a result, when the battery cell undergoes thermal runaway, there is less space left for gas to escape, that is, the pressure relief space is reduced. Further, for a battery cell with an explosion-proof valve arranged at the bottom, when it undergoes thermal runaway, the bottom support plate between the electrode group and the explosion-proof valve is prone to melting and causing the electrode group to sink, which will block the explosion-proof valve and affect the pressure relief of the battery cell, and may further lead to an explosion of the battery cell. Utility Model Content

[0003] In view of this, the purpose of this application is to provide a battery cell, a battery module, and a battery pack to solve the problem that when a battery cell with an explosion-proof valve at the bottom undergoes thermal runaway, it is extremely easy to cause the electrode group to sink and affect exhaust.

[0004] According to the above purpose, the first aspect of the present utility model provides a battery cell, wherein the battery cell includes:

[0005] A housing provided with an explosion-proof valve group; and

[0006] An electrode group located inside the housing; a concave portion corresponding to the explosion-proof valve group is formed on one side of the electrode group facing the explosion-proof valve group.

[0007] Preferably, the explosion-proof valve group is located at the first end in the height direction of the electrode group, and the explosion-proof valve group includes at least a first explosion-proof valve and a second explosion-proof valve, and the first explosion-proof valve and the second explosion-proof valve are arranged at intervals along the length direction of the electrode group.

[0008] Preferably, the concave portion is located at the first end in the height direction of the electrode group.

[0009] Preferably, the concave portion includes a first concave portion and a second concave portion corresponding to the first explosion-proof valve and the second explosion-proof valve respectively.

[0010] Preferably, along the length direction of the electrode group, the length of the opening of the first concave portion is greater than the length of the first explosion-proof valve, and the length of the opening of the second concave portion is greater than the length of the second explosion-proof valve;

[0011] And / or, along the width direction of the electrode group, the width of the opening of the first concave portion is greater than the width of the first explosion-proof valve, and the width of the opening of the second concave portion is greater than the width of the second explosion-proof valve.

[0012] Preferably, the electrode group includes a plurality of positive electrode plates and negative electrode plates, which are stacked alternately in sequence; each positive electrode plate and each negative electrode plate are formed with a first sub-recess and a second sub-recess;

[0013] The plurality of first sub-recesses form the first recess, and the plurality of second sub-recesses form the second recess.

[0014] Preferably, along the height direction of the electrode group, the depression depth of the first sub-recess is formed as L1, where 1 mm < L1 < 5 mm; and / or, the depression depth of the second sub-recess is formed as L2, where 1 mm < L2 < 5 mm.

[0015] Preferably, positive electrode tabs and negative electrode tabs are respectively formed at both ends in the length direction of the electrode group, and the housing is provided with a positive electrode post and a negative electrode post respectively connected to the positive electrode tab and the negative electrode tab.

[0016] According to a second aspect of the present invention, a battery module is provided, wherein the battery module includes the battery cell as described above.

[0017] According to a third aspect of the present invention, a battery pack is provided, wherein the battery pack is provided with the battery module as described above.

[0018] According to the battery cell, battery module and battery pack of the present invention, a recess corresponding to the explosion-proof valve group is formed on the side of the electrode group facing the explosion-proof valve group. Thus, when the battery cell undergoes thermal runaway, resulting in the melting of the bottom support plate and the sinking of the electrode group, a certain space is left between the electrode group and the explosion-proof valve through this recess, so that the high-temperature and high-pressure gas inside the battery cell can be smoothly discharged from the explosion-proof valve, ensuring the use safety of the battery cell.

[0019] To make the above objects, features and advantages of the present application more obvious and understandable, the following specifically enumerates preferred embodiments and, in conjunction with the accompanying drawings, makes the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] To more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present application and should not be regarded as limiting the scope. For those of ordinary skill in the art, other related drawings can be obtained based on these drawings without creative efforts.

[0021] Figure 1 is a schematic diagram of a battery cell according to an embodiment of the present invention;

[0022] Figure 2 is a schematic diagram of an electrode group according to an embodiment of the present invention;

[0023] Figure 3 is a schematic diagram of a positive electrode sheet according to an embodiment of the present utility model;

[0024] Figure 4 is a schematic diagram of a negative electrode sheet according to an embodiment of the present utility model.

[0025] Icons: 1 - housing; 10 - positive electrode terminal; 11 - negative electrode terminal; 12 - first explosion-proof valve; 13 - second explosion-proof valve; 2 - electrode group; 20 - positive electrode tab; 21 - negative electrode tab; 22 - first recess; 23 - second recess; 24 - positive electrode sheet; 25 - negative electrode sheet; 260 - first sub-recess; 261 - second sub-recess. Detailed implementation manners

[0026] The following detailed implementation manners 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 apparent. For example, the order of operations described herein is merely an example and is not limited to the order set forth herein. Rather, changes that will be apparent after understanding the disclosure of the present application can be made, except for operations that must occur in a specific order. In addition, descriptions of features known in the art may be omitted for the sake of clarity and conciseness.

[0027] 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 apparent after understanding the disclosure of the present application.

[0028] Throughout the specification, when an element (such as a layer, region, or substrate) is described as "on" another element, "connected to" another element, "bonded to" another element, "above" another element, or "covering" another element, it may be directly "on" another element, "connected to" another element, "bonded to" another element, "above" another element, or "covering" another element, or there may be one or more other elements therebetween. In contrast, when an element is described as "directly on" another element, "directly connected to" another element, "directly bonded to" another element, "directly above" another element, or "directly covering" another element, there may be no other elements therebetween.

[0029] 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.

[0030] Although terms such as "first", "second", and "third" may be used herein to describe various components, elements, regions, layers, or sections, these components, elements, regions, layers, or sections are not limited by these terms. Rather, these terms are only used to distinguish one component, element, region, layer, or section from another. Thus, a first component, element, region, layer, or section as referred to in the examples described herein may also be termed a second component, element, region, layer, or section without departing from the teachings of the examples.

[0031] 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 encompass 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 turned over, an element described as "above" or "upper" relative to another element will then be "below" or "lower" relative to the other element. Thus, the term "above" includes both the orientation 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 at other orientations), and the spatial relationship terms used herein will be interpreted accordingly.

[0032] The terms used herein are for the purpose of describing various examples only and are not intended to limit the disclosure. Unless the context clearly dictates otherwise, the singular forms are also intended to include the plural forms. The terms "comprises", "comprising", and "having" list the stated features, quantities, operations, components, elements, and / or combinations thereof that exist, but do not preclude the presence or addition of one or more other features, quantities, operations, components, elements, and / or combinations thereof.

[0033] Due to manufacturing techniques and / or tolerances, variations in the shapes shown in the figures may occur. Thus, the examples described herein are not limited to the specific shapes shown in the figures, but include changes in shape that occur during manufacturing.

[0034] The features of the examples described herein may be combined in various ways that will be apparent after understanding the disclosure of this application. Further, although the examples described herein have a variety of configurations, other configurations are possible as will be apparent after understanding the disclosure of this application.

[0035] According to a first aspect of the present utility model, there is provided an electric cell, such as Figures 1 to 4As shown, the battery cell in this embodiment includes a housing 1 and a pole group 2 disposed in the housing 1. The housing 1 is provided with an explosion-proof valve group, and a concave portion corresponding to the explosion-proof valve group is formed on one side of the pole group 2 facing the explosion-proof valve group. Hereinafter, the specific structures of the above-mentioned various parts of the battery cell according to the present invention will be described in detail.

[0036] In this embodiment, the explosion-proof valve group is located at the first end in the height direction of the pole group 2 (that is, as Figure 1 shown, the explosion-proof valve group is located at the bottom end of the pole group 2). The explosion-proof valve group includes a first explosion-proof valve 12 and a second explosion-proof valve 13, and the two are arranged at intervals along the length direction of the pole group 2; correspondingly, the concave portion is formed at the first end in the height direction of the pole group 2, and the concave portion includes a first concave portion 22 and a second concave portion 23 corresponding to the first explosion-proof valve 12 and the second explosion-proof valve 13 respectively. It should be noted that the number of explosion-proof valves in the explosion-proof valve group is not fixed, as long as a corresponding concave portion is formed at the top of each explosion-proof valve, so as to facilitate the exhaust and pressure relief of the battery cell.

[0037] Furthermore, in order to ensure the exhaust effect of the explosion-proof valve, along the length direction of the pole group 2, the length of the opening of the first concave portion 22 should be greater than the length of the first explosion-proof valve 12, and the length of the opening of the second concave portion 23 should be greater than the length of the second explosion-proof valve 13; along the width direction of the pole group 2, the width of the opening of the first concave portion 22 should be greater than the width of the first explosion-proof valve 12, and the width of the opening of the second concave portion 23 should be greater than the width of the second explosion-proof valve 13.

[0038] It should be noted that the shapes and sizes of the first concave portion 22 and the second concave portion 23 are not fixed. For example, in the embodiment, both the first concave portion 22 and the second concave portion 23 are formed as trapezoidal structures, or they can also be formed as arc-shaped structures, as long as the exhaust effect of the explosion-proof valve can be ensured.

[0039] In this embodiment, the pole group 2 includes a plurality of positive electrode plates 24 and negative electrode plates 25, and the positive electrode plates 24 and the negative electrode plates 25 are stacked alternately in sequence to form the pole group 2. Each positive electrode plate 24 and each negative electrode plate 25 are formed with a first sub-concave portion 260 and a second sub-concave portion 261. When the positive electrode plates 24 and the negative electrode plates 25 are stacked, a plurality of first sub-concave portions 260 form the above-mentioned first concave portion 22, and a plurality of second sub-concave portions 261 form the above-mentioned second concave portion 23. Along the height direction of the pole group 2, the depression depth of the first sub-concave portion 260 is formed as L1, 1 mm < L1 < 5 mm; the depression depth of the second sub-concave portion 261 is formed as L2, 1 mm < L2 < 5 mm.

[0040] In addition, positive electrode tabs 20 and negative electrode tabs 21 are respectively formed at both ends in the length direction of the pole group 2, and the housing 1 is also provided with a positive electrode post 10 and a negative electrode post 11 respectively connected to the positive electrode tabs 20 and the negative electrode tabs 21.

[0041] For the battery cell according to the present utility model, a recess corresponding to the explosion-proof valve group is formed on the side of the electrode group 2 facing the explosion-proof valve group. Thus, when the battery cell undergoes thermal runaway, resulting in the melting of the bottom support plate and the sinking of the electrode group 2, a certain space is left between the electrode group 2 and the explosion-proof valve through this recess. Furthermore, the high-temperature and high-pressure gas inside the battery cell can be smoothly discharged from the explosion-proof valve, so as to ensure the safe use of the battery cell.

[0042] According to a second aspect of the present utility model, a battery module is provided, and the battery module includes the battery cell as described above.

[0043] According to a third aspect of the present utility model, a battery pack is provided, and the battery pack is provided with the battery module as described above.

[0044] Finally, it should be noted that: the above-described embodiments are only specific embodiments of the present application, used to illustrate the technical solutions of the present application, rather than limiting it. 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 recorded in the foregoing embodiments, or can easily think of changes, or perform equivalent replacements on 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 by 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 provided with an explosion-proof valve group; the explosion-proof valve group includes a first explosion-proof valve and a second explosion-proof valve, and a pole group located inside the housing, the first explosion-proof valve and the second explosion-proof valve are arranged at intervals along the length direction of the pole group; a concave portion corresponding to the explosion-proof valve group is formed on one side of the pole group facing the explosion-proof valve group; the concave portion includes a first concave portion and a second concave portion corresponding to the first explosion-proof valve and the second explosion-proof valve respectively; along the length direction of the pole group, the length of the opening of the first concave portion is greater than the length of the first explosion-proof valve, and the length of the opening of the second concave portion is greater than the length of the second explosion-proof valve; and / or, along the width direction of the pole group, the width of the opening of the first concave portion is greater than the width of the first explosion-proof valve, and the width of the opening of the second concave portion is greater than the width of the second explosion-proof valve; the pole group includes a plurality of positive electrode plates and negative electrode plates, and the positive electrode plates and the negative electrode plates are stacked alternately in sequence; each of the positive electrode plates and each of the negative electrode plates are formed with a first sub-concave portion and a second sub-concave portion; a plurality of the first sub-concave portions form the first concave portion, and a plurality of the second sub-concave portions form the second concave portion.

2. The battery cell according to claim 1, characterized in that, The explosion-proof valve group is located at the first end in the height direction of the pole group.

3. The cell according to claim 2, wherein The concave portion is located at the first end in the height direction of the pole group.

4. The battery cell according to claim 1, wherein, Along the height direction of the pole group, the depression depth of the first sub-concave portion is formed as L1, 1mm < L1 < 5mm; and / or, the depression depth of the second sub-concave portion is formed as L2, 1mm < L2 < 5mm.

5. The battery cell according to claim 1, wherein Positive electrode tabs and negative electrode tabs are respectively formed at both ends in the length direction of the pole group, and the housing is provided with a positive electrode post and a negative electrode post respectively connected to the positive electrode tab and the negative electrode tab.

6. A battery module, characterized in that, The battery module includes the battery cell according to any one of claims 1 to 5.

7. A battery pack, characterized in that, The battery pack is provided with the battery module according to claim 6.

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