Battery cells and battery modules

Abstract

The present application relates to the field of battery technology, and in particular to a battery cell and a battery module. The battery cell includes a shell, a first cover plate, and a pole group. The shell is enclosed to form a space extending along a first direction. The first cover plate is provided at one end of the shell in the first direction. An explosion-proof valve is provided on the first cover plate. Limit blocks are provided on the inner walls of both sides of the shell in the second direction. The pole group is provided in the shell, and the limit block is provided between the first cover plate and the pole group. The second direction intersects with the first direction. The size of the shell in the second direction is defined as A, the wall thickness of the shell is defined as t, the size of the pole group in the second direction is defined as B, and the size of the limit block in the second direction is defined as C. According to the battery cell and battery module provided by the present application, the pole group is effectively limited by the limit block, thereby preventing the pole group from moving in the first direction and blocking the explosion-proof valve on the first cover plate, thereby improving the safety of the battery cell.

Description

Technical Field

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

[0002] Today's battery cells typically consist of a housing, a cover, a lower plastic component, and a pole group. The housing and cover together form a closed space containing the pole group, with the lower plastic component located on the side of the cover facing the pole group. An explosion-proof valve is typically installed on the cover to allow high-pressure gas inside the housing to escape. The battery cell is primarily held in place by the lower plastic component, which acts as a pressure gauge for the pole group.

[0003] However, the insulating material used to make the lower plastic is typically plastic (such as PP), which has a low melting point. When a battery cell experiences thermal runaway, the internal temperature of the cell rises rapidly, and the lower plastic's restraining function on the electrode assembly can easily fail due to melting. This causes the electrode assembly to be easily pressed against the inner side of the cover by the impact of the high-pressure airflow inside the housing, causing the electrode assembly to block the explosion-proof valve, thereby affecting the valve's exhaust flow, reducing the valve's exhaust efficiency, and degrading the battery cell's safety. Summary of the Invention

[0004] The purpose of this application is to provide a battery cell and battery module that, to a certain extent, address the technical problem in the prior art that the insulating material used to make the lower plastic is generally made of plastic (e.g., PP) with a low melting point. When the battery cell experiences thermal runaway, as the internal temperature of the battery cell rises sharply, the lower plastic's limiting effect on the electrode group is easily lost due to the melting of the lower plastic. This makes it very easy for the electrode group to be pressed against the inner side of the cover plate under the impact of the high-pressure airflow inside the housing, thereby causing the electrode group to block the explosion-proof valve, thereby affecting the exhaust smoothness of the explosion-proof valve, reducing the exhaust effect of the explosion-proof valve, and reducing the safety performance of the battery cell.

[0005] According to a first aspect of the present application, a battery cell is provided, comprising a housing, a first cover plate, and a pole group, wherein the housing encloses a space extending along a first direction, the first cover plate is disposed on one end of the housing in the first direction, an explosion-proof valve is disposed on the first cover plate, and limit stops are disposed on inner walls on both sides of the housing in a second direction, the pole group is disposed within the housing, and the limit stops are disposed between the first cover plate and the pole group, wherein the second direction intersects the first direction;

[0006] Define the size of the shell in the second direction as A, the wall thickness of the shell as t, the size of the pole group in the second direction as B, and the size of the limit block in the second direction as C, wherein,

[0007] Preferably, 1.0 mm ≤ A-2t-B ≤ 1.6 mm.

[0008] Preferably, the size of the housing in the second direction is 80 mm to 190 mm.

[0009] Preferably, the wall thickness of the shell is 0.3 mm to 1.0 mm.

[0010] Preferably, it further comprises a first insulating portion, wherein the first insulating portion is attached to a side of the first cover plate facing the pole group;

[0011] When the first cover plate is covered on the housing, at least a portion of the first insulating portion extends into the housing, and the first insulating portion and at least a portion of the limit stopper are overlapped in the first direction.

[0012] Preferably, both outer walls of the first insulating portion in the second direction are provided with receiving grooves, and when the first cover plate is covered on the housing, the limit stopper is provided in the receiving grooves;

[0013] A difference between a size of the accommodating groove in the second direction and a size of the limit block in the second direction is h1, wherein 0.2 mm ≤ h1 ≤ 0.5 mm;

[0014] A difference between a size of the accommodating groove in the third direction and a size of the limiting block in the third direction is h2, wherein 0.2 mm ≤ h2 ≤ 0.5 mm, and the third direction is perpendicular to the second direction.

[0015] Preferably, the accommodating groove extends along the first direction, and the accommodating groove is open at one end of the first insulating portion facing the pole group.

[0016] Preferably, it further comprises a first pole, wherein the first pole and the explosion-proof valve are spaced apart and arranged on the first cover plate along the second direction.

[0017] Preferably, the housing further comprises a second pole and a second cover plate, wherein the second pole is provided on the second cover plate, and the first cover plate and the second cover plate are respectively provided on both ends of the housing in the first direction.

[0018] According to the second aspect of the present application, a battery module is provided, comprising the battery cell described in any of the above technical solutions, and thus having all the beneficial technical effects of the battery cell, which will not be described in detail here.

[0019] Compared with the prior art, the present invention has the following advantages:

[0020] The battery cell provided in the present application is provided with a limit block on both sides of the inner wall of the shell in the second direction, and the limit block is provided between the first cover and the electrode group, and the size of the limit block in the second direction is controlled. In other words, the height of the limit block is greater than 1.5 times the gap between the shell and the pole group, so that the pole group can be effectively limited by the limit block, thereby preventing the pole group from moving in the first direction and blocking the explosion-proof valve on the first cover, thereby improving the safety of the battery cell.

[0021] In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, preferred embodiments are given below and described in detail with reference to the accompanying drawings. 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 following is a brief introduction to the drawings required for use in the specific implementation methods or the description of the prior art. 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 any creative work.

[0023] Figure 1 A schematic diagram of the axonometric structure of a battery cell provided in an embodiment of the present application;

[0024] Figure 2 A schematic cross-sectional view of a battery cell according to an embodiment of the present application;

[0025] Figure 3 for Figure 2 The enlarged structural diagram of the provided battery cell at D;

[0026] Figure 4 This is another isometric structural diagram of the battery cell provided in an embodiment of the present application.

[0027] Reference numerals:

[0028] 1-shell; 11-limit block; 2-first cover plate; 21-explosion-proof valve; 22-first pole; 3-pole group; 4-first insulating portion; 41-accommodating groove; 5-second cover plate; 51-second pole; 52-second insulating portion.

[0029] F1-first direction; F2-second direction; F3-third direction. DETAILED DESCRIPTION

[0030] The following detailed description is provided to help the reader gain a comprehensive understanding of the methods, devices, and / or systems described herein. However, various changes, modifications, and equivalents of the methods, devices, and / or systems described herein will be apparent upon understanding the disclosure of this application. For example, the order of operations described herein is merely illustrative and is not limited to the order set forth herein. Rather, except for operations that must occur in a particular order, changes may be made that will be apparent upon understanding the disclosure of this application. Furthermore, descriptions of features known in the art may be omitted for clarity and brevity.

[0031] The features described herein may be implemented in different forms and should not be construed as being limited to the examples described herein. Rather, the examples described herein have been provided merely to illustrate some of the many possible ways to implement the methods, devices, and / or systems described herein that will be apparent upon understanding the disclosure of this application.

[0032] Throughout the specification, when an element (such as a layer, region, or substrate) is described as being “on,” “connected to,” “coupled to,” “over,” or “overlaying” another element, it may be directly “on,” “connected to,” “coupled to,” “over,” or “overlaying” another element, or one or more other elements may be present between them. In contrast, when an element is described as being “directly on,” “directly connected to,” “directly coupled to,” “directly over,” or “directly covering” another element, there may be no other elements intervening therebetween.

[0033] As used herein, the term "and / or" includes any one of the associated listed items and any combination of any two or more items.

[0034] Although terms such as "first," "second," and "third" may be used herein to describe various members, components, regions, layers, or portions, these members, components, regions, layers, or portions are not limited by these terms. Rather, these terms are used only to distinguish one member, component, region, layer, or portion from another member, component, region, layer, or portion. Thus, a first member, component, region, layer, or portion in the examples described herein may also be referred to as a second member, component, region, layer, or portion without departing from the teachings of the examples.

[0035] For ease of description, spatial relational terms such as "above," "upper," "below," and "lower" may be used herein to describe the relationship of one element to another element as shown in the accompanying drawings. Such spatial relational terms are intended to encompass different orientations of the device in use or operation in addition to the orientations depicted in the accompanying drawings. For example, if the device in the accompanying drawings is turned over, an element described as being "above" or "upper" relative to another element would subsequently be "below" or "lower" relative to the other element. Thus, the term "above" includes both the orientations "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 relational terms used herein will be interpreted accordingly.

[0036] The terms used herein are intended only to describe various examples and are not intended to limit the present disclosure. Unless the context clearly indicates otherwise, the singular is intended to include the plural. The terms "comprise," "include," and "have" list the presence of stated features, quantities, operations, components, elements, and / or combinations thereof, but do not preclude the presence or addition of one or more other features, quantities, operations, components, elements, and / or combinations thereof.

[0037] Due to manufacturing techniques and / or tolerances, variations in the shapes shown in the drawings may occur. Therefore, the examples described herein are not limited to the specific shapes shown in the drawings but include changes in shapes that occur during manufacturing.

[0038] 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.

[0039] Refer to the following Figures 1 to 4 The present invention describes a battery cell and a battery module according to some embodiments of the present application.

[0040] See also Figures 1 to 4As shown, an embodiment of the first aspect of the present application provides a battery cell, which includes a shell 1, a first cover plate 2 and a pole group 3. The shell 1 is enclosed to form a space extending along the first direction F1. The first cover plate 2 is provided on one end of the shell 1 in the first direction F1. The first cover plate 2 is provided with an explosion-proof valve 21. The inner walls of the shell 1 on both sides in the second direction F2 are provided with limit blocks 11. The pole group 3 is provided in the shell 1, and the limit block 11 is provided between the first cover plate 2 and the pole group 3. The second direction F2 intersects with the first direction F1. The dimension of the shell 1 in the second direction F2 is defined as A, the wall thickness of the shell 1 is defined as t, the dimension of the pole group 3 in the second direction F2 is defined as B, and the dimension of the limit block 11 in the second direction F2 is defined as C, wherein,

[0041] Table 1 shows that samples of electrode groups 3 and limit blocks 11 of different sizes were prepared (at least 5 samples of each size were trial-produced), and the electrode group 3 and the shell 1 were assembled, as well as the electrode group 3 limit test of the battery cell in the thermal runaway state was carried out respectively. The results are shown in the following table.

[0042] Table 1:

[0043]

[0044]

[0045] According to Table 1, when When (i.e. samples No. 1 to 4), the shelling yield rate and / or the problem of poor positioning of the limit block 11 on the electrode group 3 appeared to varying degrees. When (i.e., sample No. 5 and sample No. 6), the five samples of each size can be well inserted into the shell and the limit block 11 can well limit the pole group 3 during the battery cell safety test (i.e., under thermal runaway condition).

[0046] In summary, according to the battery cell provided by the above technical features, the limit blocks 11 are provided on the inner walls of both sides of the housing 1 in the second direction F2, and the limit blocks 11 are provided between the first cover plate 2 and the electrode group 3, and the size of the limit blocks 11 in the second direction F2 is controlled. Right now In other words, the height of the limit block 11 is 1.5 times greater than the size of the gap between the shell 1 and the pole group 3 in the second direction F2, so that the pole group 3 can be effectively limited by the limit block 11, thereby avoiding the pole group 3 from moving in the first direction F1 and blocking the explosion-proof valve 21 on the first cover plate 2, thereby improving the safety of the battery cell.

[0047] like Figures 1 to 4As shown, F1 shown in the figure can be an example of the first direction F1 mentioned above, and F2 shown in the figure can be an example of the second direction F2 mentioned above, wherein the first direction F1 and the second direction F2 intersect each other. Preferably, the first direction F1 and the second direction F2 are perpendicular to each other to accommodate most examples of square batteries. For ease of description, the direction perpendicular to the plane defined by the first direction F1 and the second direction F2 is defined as a third direction F3, and F3 shown in the figure can be an example of this third direction F3.

[0048] by Figures 1 to 4 Taking the example shown as an example, preferably, the first direction F1 may be the length direction of the square battery, the second direction F2 may be the width direction of the square battery, and the third direction F3 may be the thickness direction of the square battery.

[0049] However, the present invention is not limited thereto. The first direction F1 may also be considered as the width direction or thickness direction of the square battery. Correspondingly, the second direction F2 and the third direction F3 may be adaptively adjusted based on the first direction F1.

[0050] Preferably, if Figure 2 As shown, in the second direction F2, the total gap between the shell 1 and the pole group 3 (i.e., A-2t-B) can be 1.0mm-1.6mm, that is, 1.0mm≤A-2t-B≤1.6mm, to ensure smooth insertion of the pole group 3 into the shell.

[0051] Preferably, if Figure 2 As shown, the size of the housing 1 in the second direction F2 (ie, the value A shown in the figure) can be 80 mm to 190 mm to accommodate the sizes of most square batteries.

[0052] Preferably, if Figure 3 As shown, the wall thickness of the housing 1 (ie, the t value shown in the figure) can be 0.3 mm to 1.0 mm to ensure the strength of the housing 1.

[0053] Preferably, if Figure 3 As shown, the above-mentioned limit stopper 11 can be integrally connected to the above-mentioned shell 1 to ensure the connection strength between the limit stopper 11 and the inner wall of the shell 1.

[0054] Preferably, if Figure 3 As shown, the above-mentioned limit stopper 11 can be formed by integrally stamping the housing 1 .

[0055] However, it is not limited to this. As long as the connection stability between the limit block 11 and the shell 1 is guaranteed, the connection method between the limit block 11 and the inner wall of the shell 1 is not limited to the example of integral stamping. For example, the limit block 11 and the shell 1 are welded together, or the limit block 11 and the shell 1 are bonded together.

[0056] Preferably, the above-mentioned limit stopper 11 can be a high-temperature resistant part, such as a metal part, a ceramic part, etc.

[0057] In an embodiment, preferably, Figures 1 to 4 As shown, the battery cell may further include a first insulating portion 4 , which may be attached to the side of the first cover plate 2 facing the electrode group 3 , so as to achieve insulation between the first cover plate 2 and the electrode group 3 .

[0058] Preferably, if Figure 2 As shown, when the first cover plate 2 is covered on the housing 1 , at least a portion of the first insulating portion 4 extends into the housing 1 and overlaps with at least a portion of the limit block 11 to save space for the battery cell in the first direction F1 .

[0059] Preferably, if Figure 2 As shown, when the first cover plate 2 is covered on the shell 1, at least a portion of the first insulating portion 4 abuts against the electrode group 3, so that when the battery cell is in normal use, the electrode group 3 is limited by the first insulating portion 4 to ensure the stability of the battery cell in normal use.

[0060] Preferably, the first insulating portion 4 and the second insulating member described below may both be insulating plastic members.

[0061] Preferably, if Figures 1 to 4 As shown, the outer walls on both sides of the first insulating part 4 in the second direction F2 are provided with accommodating grooves 41. When the first cover plate 2 is covered on the shell 1, the limit block 11 is arranged in the accommodating groove 41, so as to reduce the space occupied by the limit block 11 in the battery cell.

[0062] Preferably, as shown in Table 2, the difference between the size of the accommodating groove 41 in the second direction F2 and the size of the limit block 11 in the second direction F2 is h1, wherein 0.2 mm ≤ h1 ≤ 0.5 mm. In other words, when the limit block 11 is arranged in the accommodating groove 41, a certain assembly gap is formed between the limit block 11 and the inner wall of the accommodating groove 41 in the second direction F2, so as to take into account both the smoothness of the limit block 11 being installed into the accommodating groove 41 and the strength of the first insulating part 4.

[0063] Similarly, as shown in Table 2, the difference between the size of the accommodating groove 41 in the third direction F3 and the size of the limit block 11 in the third direction F3 is h2, where 0.2 mm ≤ h2 ≤ 0.5 mm. In other words, when the limit block 11 is arranged in the accommodating groove 41, a certain assembly gap is formed between the limit block 11 and the inner wall of the accommodating groove 41 in the third direction F3, so as to take into account both the smoothness of the limit block 11 being installed into the accommodating groove 41 and the strength of the first insulating part 4.

[0064] Table 2 shows that samples were prepared with accommodating grooves 41 and limit blocks 11 of different sizes and specifications, and the electrode group 3 and the housing 1 were assembled respectively. The results are shown in the following table.

[0065] Table 2:

[0066]

[0067] Preferably, if Figures 1 to 4 As shown, the accommodating groove 41 extends along the first direction F1 , and the accommodating groove 41 is open at one end of the first insulating part 4 facing the pole group 3 , so as to facilitate assembly of the first insulating part 4 and the housing 1 .

[0068] In an embodiment, Figure 1 、 Figure 2 and Figure 4 As shown, the battery cell may further include a first pole 22 , which is spaced apart from the explosion-proof valve 21 along the second direction F2 on the first cover plate 2 to prevent the first pole 22 from interfering with exhaust of the explosion-proof valve 21 .

[0069] Preferably, if Figure 1 、 Figure 2 and Figure 4 As shown, the battery cell may further include a second cover plate 5 . The first cover plate 2 and the second cover plate 5 are respectively arranged to cover both ends of the housing 1 in the first direction F1 to facilitate assembly of the battery cell.

[0070] Preferably, if Figure 2 and Figure 4 As shown, the battery cell may further include a second insulating portion 52 , which is attached to a side of the second cover plate 5 facing the electrode group 3 to achieve insulation between the second cover plate 5 and the electrode group 3 .

[0071] Similarly, the second insulating portion 52 may also abut against the electrode group 3 to limit the end of the electrode group 3 away from the first cover plate 2 .

[0072] Preferably, if Figure 1 、 Figure 2 and Figure 4 As shown, the battery cell may further include a second pole 51 , and the second pole 51 may be provided on the second cover plate 5 .

[0073] Optionally, not shown in the figures, the first pole and the second pole may both be provided on the first cover plate.

[0074] Optionally, not shown in the figures, the first pole and the second pole may both be provided on the second cover plate.

[0075] The embodiment of the second aspect of the present application further provides a battery module, comprising the battery cell described in any of the above embodiments, and thus having all the beneficial technical effects of the battery cell, which will not be repeated here.

[0076] Finally, it should be noted that the above-described embodiments are only specific implementation methods of the present application, which are used to illustrate the technical solutions of the present application, rather than to limit them. The scope of protection of the present application is not limited thereto. Although the present application has been described in detail with reference to the above-described embodiments, those skilled in the art should understand that any person skilled in the art can modify or easily conceive of changes to the technical solutions described in the above-described embodiments within the technical scope disclosed in the present application, or perform equivalent replacements for some of the technical features thereof. These modifications, changes, or replacements do not deviate from the spirit and scope of the technical solutions of the embodiments of the present application, and should be included in the scope of protection of the present application. Therefore, the scope of protection of the present application shall be subject to the scope of protection of the claims.

Claims

1. A battery cell, characterized in that: The device comprises a housing, a first cover plate, and an electrode group, wherein the housing encloses a space extending in a first direction, the first cover plate is provided on one end of the housing in the first direction, an explosion-proof valve is provided on the first cover plate, and limit stops are provided on inner walls on both sides of the housing in a second direction. The electrode group is provided in the housing, and the limit stops are provided between the first cover plate and the electrode group, and the second direction intersects the first direction. Define the size of the shell in the second direction as A, the wall thickness of the shell as t, the size of the pole group in the second direction as B, and the size of the limit block in the second direction as C, wherein, ; It also includes a first insulating portion, the first insulating portion being attached to a side of the first cover plate facing the pole group; When the first cover is placed on the housing, at least a portion of the first insulating portion extends into the housing, and the first insulating portion and at least a portion of the stopper overlap in the first direction. The outer walls of both sides of the first insulating portion in the second direction are provided with accommodating grooves, and when the first cover plate is covered on the housing, the limit block is arranged in the accommodating grooves.

2. The battery cell according to claim 1, characterized in that 。 3. The battery cell according to claim 1, characterized in that The size of the shell in the second direction is 80 mm to 190 mm.

4. The battery cell according to claim 1, characterized in that The wall thickness of the shell is 0.3mm~1.0mm.

5. The battery cell according to claim 1, characterized in that A difference between a size of the accommodating groove in the second direction and a size of the limit block in the second direction is h1, wherein 0.2 mm ≤ h1 ≤ 0.5 mm; A difference between a size of the accommodating groove in the third direction and a size of the limiting block in the third direction is h2, wherein 0.2 mm ≤ h2 ≤ 0.5 mm, and the third direction is perpendicular to the second direction.

6. The battery cell according to claim 1, characterized in that The accommodating groove extends along the first direction, and the accommodating groove is open at one end of the first insulating portion facing the pole group.

7. The battery cell according to claim 1, characterized in that It also includes a first pole, which is spaced apart from the explosion-proof valve and arranged on the first cover along the second direction.

8. The battery cell according to claim 7, characterized in that The housing further includes a second pole and a second cover plate, wherein the second pole is provided on the second cover plate, and the first cover plate and the second cover plate are respectively provided on both ends of the housing in the first direction.

9. A battery module, characterized in that: A battery cell comprising the battery cell according to any one of claims 1 to 8.

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