Shell structure and battery

Abstract

The present application relates to the field of battery technology, and more particularly to a housing structure and battery. The housing structure comprises a housing and a cover, the cover being provided with an explosion-proof valve. The cover is positioned over one end of the housing in a first direction, and the cover and housing together enclose a closed space for accommodating an electrode group. A limiter assembly is provided on the inner wall of the housing near one end of the cover. The limiter assembly protrudes into the interior of the closed space relative to the inner wall and is positioned between the cover and the electrode group. The perimeter of a figure formed by cutting the closed space with a plane perpendicular to the first direction is defined as C, and the sum of the lengths of the limiter assembly in the circumferential direction of the closed space facing the end of the electrode group is defined as A, with 45% ≤ A / C ≤ 65%. The housing structure and battery provided by the present application ensure that the limiter assembly effectively limits the electrode group and that gases within the housing can be discharged smoothly through the explosion-proof valve in the event of battery overheating.

Description

Technical Field

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

[0002] Today's batteries typically consist of a housing, a cover, a lower plastic component, and a pole assembly. The housing and cover together enclose the pole assembly, with the lower plastic component located on the side of the cover facing the pole assembly. The cover is typically equipped with an explosion-proof valve to vent high-pressure gas within the housing. The battery's lower plastic component primarily presses against the pole assembly to maintain the battery housing's position.

[0003] However, the insulating material used to make the lower plastic is typically plastic (e.g., PP), which has a low melting point. When the battery experiences thermal runaway, the internal temperature of the battery 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 venting smoothness, reducing the valve's venting effectiveness, and degrading the battery's safety. Summary of the Invention

[0004] The present application aims to provide a housing structure and a battery that, to a certain extent, addresses the existing technical problem 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 experiences thermal runaway, as the internal temperature of the battery rises sharply, the lower plastic's restraining effect on the electrode assembly is easily lost due to the melting of the lower plastic. This makes it very easy for the electrode assembly to be pressed against the inner side of the cover under the impact of the high-pressure airflow inside the housing, thereby causing the electrode assembly to block the explosion-proof valve, thereby affecting the smoothness of the explosion-proof valve's exhaust, reducing the exhaust efficiency of the explosion-proof valve, and reducing the safety performance of the battery.

[0005] According to a first aspect of the present application, a housing structure is provided, comprising a housing and a cover, wherein the cover is provided with an explosion-proof valve and is disposed on one end of the housing in a first direction, wherein the cover and the housing together enclose a closed space for accommodating an electrode group;

[0006] A limiting assembly is provided on the inner wall of the housing near one end of the cover body, the limiting assembly protrudes toward the interior of the enclosed space relative to the inner wall, and the limiting assembly is provided between the cover body and the pole group;

[0007] The perimeter of a figure formed by cutting the closed space with a plane perpendicular to the first direction is defined as C, and the sum of the lengths of the end of the limiting assembly facing the pole group in the circumferential direction of the closed space is defined as A;

[0008] Among them, 45%≤A / C≤65%.

[0009] Preferably, the limiting assembly includes a plurality of limiting portions, and the plurality of limiting portions are arranged at intervals along the circumferential direction.

[0010] Preferably, end surfaces of the plurality of limiting portions on a side facing the pole group are aligned with each other in the first direction to form a limiting array.

[0011] Preferably, the limiting assembly includes one or more limiting arrays;

[0012] If there are multiple spacer groups, the multiple spacer groups are spaced apart along the first direction.

[0013] Preferably, the total length of the limiting assembly in the circumferential direction at one end facing the pole group is the sum of the dimensions in the circumferential direction of all limiting portions included in the one closest to the pole group among the plurality of limiting arrays.

[0014] Preferably, in the circumferential direction, the limiting portions of the plurality of limiting arrays are staggered with each other.

[0015] Preferably, the limiting assembly is integrally connected to the inner wall of the shell.

[0016] Preferably, an insulating member is further included, which is arranged on a side of the cover body facing the pole group, and when the cover body and the shell are covered with each other, at least a part of the insulating member extends into the closed space.

[0017] Preferably, when the cover and the housing are covering each other, at least a portion of the insulating member and the limiting assembly overlap with each other in the first direction.

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

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

[0020] The shell structure provided by the present application can effectively limit the pole group when the limit assembly meets the A / C ≥ 45%, so that the pole group can still remain without obvious movement when the battery is overheated and impacted by internal gas, thereby effectively avoiding the pole group blocking the explosion-proof valve and causing danger. And controlling the A / C of the limit assembly within the range of less than or equal to 65% can effectively prevent the limit assembly from being too large, blocking the exhaust channel of the battery, and affecting the automatic opening of the explosion-proof valve. In summary, when the limit assembly meets the condition of 45% ≤ A / C ≤ 65%, the shell ensures that the limit assembly effectively limits the pole group and ensures that the gas inside the shell can be smoothly discharged through the explosion-proof valve when the battery is overheated. The safety of the battery is guaranteed.

[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 This is a schematic diagram of the axonometric structure of the shell structure provided in an embodiment of the present application.

[0024] Reference numerals:

[0025] 1-shell; 11-large surface; 12-narrow side; 13-limiting part; 2-cover; 21-explosion-proof valve; 221-first pole; 222-second pole; 3-insulating part; 31-avoidance groove; 4-pole group.

[0026] F1-first direction; F2-second direction; F3-third direction. DETAILED DESCRIPTION

[0027] 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 the embodiments.

[0028] The components of the embodiments of the present application generally described and shown in the drawings herein may be arranged and designed in a variety of 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 claimed application, but merely represents selected embodiments of the present application.

[0029] 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.

[0030] In the description of this application, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings and are intended solely to facilitate the description of this application and simplify the description. They do not indicate or imply that the devices or components referred to must have a specific orientation, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limitations on this application. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0031] In the description of this application, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integral connections; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and internal connections between two components. Those skilled in the art will understand the specific meanings of the above terms in this application based on the specific circumstances.

[0032] Refer to the following Figure 1 The present invention describes a housing structure and a battery according to some embodiments of the present application.

[0033] See also Figure 1 As shown, an embodiment of the first aspect of the present application provides a shell structure, which includes a shell 1 and a cover body 2, wherein the cover body 2 is provided with an explosion-proof valve 21, and the cover body 2 is provided on one end of the shell 1 in the first direction F1, and the cover body 2 and the shell 1 are enclosed to form a closed space for accommodating the pole group 4. A limiting assembly is provided on the inner wall of the shell 1 near one end of the cover body 2, and the limiting assembly protrudes toward the inside of the closed space relative to the inner wall, and the limiting assembly is provided between the cover body 2 and the pole group 4. The perimeter of the figure formed by cutting the closed space with a plane perpendicular to the first direction F1 is defined as C, and the sum of the lengths of the limiting assembly in the circumferential direction of the closed space at one end facing the pole group 4 is defined as A, wherein 45%≤A / C≤65%.

[0034] Referring to Table 1, it shows that under the structure of the shell 1 of the same size, different sizes of limiting components are selected. Five samples are trial-produced for each size of limiting component, and they are assembled with the electrode group 4 respectively to test the limiting effect of the limiting component on the electrode group 4 in the assembled battery under the environment of overheating exhaust.

[0035]

[0036]

[0037] It can be seen from this that when the limit assembly meets the A / C ≥ 45%, the limit assembly can effectively limit the electrode group 4, so that the electrode group 4 can still remain without obvious movement when the battery overheats and is impacted by internal gas, thereby effectively preventing the electrode group 4 from blocking the explosion-proof valve 21 and causing danger. Moreover, controlling the A / C of the limit assembly within a range of less than or equal to 65% can effectively prevent the limit assembly from being too large, blocking the battery's exhaust channel, and affecting the automatic opening of the explosion-proof valve 21. In summary, when the limit assembly meets the condition of 45% ≤ A / C ≤ 65%, the shell 1 ensures that the limit assembly effectively limits the electrode group 4 and ensures that the gas inside the shell 1 can be smoothly discharged through the explosion-proof valve 21 when the battery overheats. The safety of the battery is guaranteed.

[0038] like Figure 1 As shown, F1 shown in the figure can be an example of the first direction F1. For ease of description, two directions intersecting each other on a plane perpendicular to the first direction F1 are defined as a second direction F2 and a third direction F3, respectively. F2 shown in the figure can be an example of the second direction F2, and F3 shown in the figure can be an example of the third direction F3. Taking the example of the housing structure shown in the figure being applicable to a prismatic battery, preferably, the first direction F1 can be the length direction of the prismatic battery, the second direction F2 can be the width direction of the prismatic battery, and the third direction F3 can be the thickness direction of the prismatic battery.

[0039] Preferably, if Figure 1 As shown, the above-mentioned limiting assembly may include multiple limiting protrusions, and the multiple limiting protrusions may be arranged at intervals along the above-mentioned circumferential direction. In this way, the gap formed between adjacent limiting portions 13 can make it easier for the gas inside the shell 1 to flow to the explosion-proof valve 21.

[0040] Preferably, if Figure 1 As shown, the end faces of the plurality of limiting portions 13 facing the electrode group 4 are aligned with each other in the first direction F1 to form a limiting array. In this way, the limiting array can simultaneously abut against the electrode group 4 in the circumferential direction, thereby effectively increasing the abutment area between the limiting array and the electrode group 4 during the battery overheating and exhaust process, thereby preventing the electrode group 4 from being damaged during the battery overheating and exhaust process.

[0041] Preferably, if Figure 1The figure shows an example in which the above-mentioned limiting component includes two limiting groups, and the two limiting groups can be spaced apart along the first direction F1. On the one hand, two limiting groups are set so that once one of the two limiting groups close to the electrode group 4 fails to limit the electrode group 4, the shell 1 can rely on the other of the two limiting groups to limit the electrode group 4, further improving the limiting stability of the limiting component on the electrode group 4; on the other hand, the two limiting groups are spaced apart to further ensure the smoothness of the exhaust inside the battery shell 1.

[0042] Furthermore, if Figure 1 As shown, in the circumferential direction, the limiting portions 13 of the plurality of limiting arrays are staggered with each other to further ensure smooth exhaust inside the battery housing 1 .

[0043] Preferably, if Figure 1 As shown, in the same limiting arrangement, the distance between two adjacent limiting portions 13 in the circumferential direction may be greater than the size of the limiting portion 13 in the circumferential direction, so as to further ensure smooth exhaust inside the battery housing 1 .

[0044] However, it is not limited to this. The number of limiting groups included in the above-mentioned limiting component is not limited to the above-mentioned two examples. As long as the limiting property of the limiting component to the pole group 4 can be guaranteed, the number of limiting groups included in the above-mentioned limiting component can also be 1, 3, 4... or more.

[0045] like Figure 1 As shown, taking the example of the above-mentioned shell structure being applicable to a square-shell battery as an example, the perimeter C of a figure formed by cutting the closed space with a plane perpendicular to the first direction F1 is C=2×(C1+C2).

[0046] Correspondingly, if Figure 1 As shown, the total length of the limiting assembly facing the pole group 4 in the circumferential direction is the sum of the circumferential dimensions of all limiting portions 13 included in the one closest to the pole group 4 among the multiple limiting rows.

[0047] Optionally, the circumferential dimensions of each limiting portion 13 in the limiting assembly are equal. Correspondingly, the total circumferential length of the limiting assembly at one end facing the pole group 4 is A=n×a.

[0048] Preferably, taking the above shell structure as an example of being applicable to square shell batteries, Figure 1 As shown, the above-mentioned shell 1 may include narrow side surfaces 12 arranged on both sides of the shell 1 in the second direction F2 and large surfaces 11 arranged on both sides of the shell 1 in the third direction F3. The narrow side surfaces 12 and the large surfaces 11 are alternately connected end to end to form the above-mentioned shell 1.

[0049] Preferably, if Figure 1As shown, the size of the limiting portion 13 provided on the narrow side surface 12 in the circumferential direction (ie, Figure 1 a2) is smaller than the size of the limiting portion 13 provided on the large surface 11 in the circumferential direction (ie, Figure 1 a1) is shown so that the limiting portion 13 is better adapted to the above-mentioned housing structure.

[0050] Correspondingly, if Figure 1 As shown, the total length A of the above-mentioned limiting assembly in the circumferential direction facing one end of the pole group 4 is 2×(n1×a1+n2×a2), wherein n1 is the number of the same limiting group arrangement on the narrow side surface 12, and n2 is the number of the same limiting group arrangement on the narrow side surface 12.

[0051] Preferably, the above-mentioned limiting assembly can be integrally connected to the inner wall of the shell 1 to further ensure the connection stability between the limiting assembly and the shell 1, thereby ensuring the limiting stability of the limiting assembly to the electrode group 4.

[0052] In an embodiment, preferably, Figure 1 The shell structure may further include an insulating member 3, which may be provided on the side of the cover 2 facing the pole group 4, and when the cover 2 and the shell 1 are covered with each other, at least a portion of the insulating member 3 extends into the enclosed space. Thus, on the one hand, insulation between the cover 2 and the pole group 4 is effectively achieved through the insulating member 3; on the other hand, at least a portion of the insulating member 3 extends into the enclosed space, so that when the battery is in normal use, the pole group 4 is limited by the insulating member 3, thereby further ensuring the stability of the pole group 4 in use.

[0053] Preferably, when the cover 2 and the shell 1 cover each other, at least part of the insulating member 3 and the limiting assembly overlap each other in the first direction F1 to save the size of the shell structure in the first direction F1, thereby improving the space utilization of the shell structure.

[0054] Preferably, if Figure 1 As shown, the side wall of the insulating member 3 may also be provided with an avoidance groove 31. When the cover 2 and the shell 1 are covered with each other, the limiting portion 13 may be provided in the avoidance groove 31 to further save space utilization of the shell structure.

[0055] Preferably, if Figure 1 As shown, the avoidance groove 31 is formed open at one end of the insulating member 3 facing the pole group 4 to facilitate assembly of the insulating member 3 and the limiting portion 13 .

[0056] According to the second aspect of the present application, a battery is provided, comprising the shell structure described in any of the above technical solutions, and thus having all the beneficial technical effects of the shell structure, which will not be described in detail here.

[0057] Preferably, if Figure 1 As shown, the battery may include a first pole 221 and a second pole 222. The first pole 221 may be provided on the cover 2, and the second pole 222 may be provided on an end of the housing 1 away from the cover 2 in the first direction F1.

[0058] Optionally, not shown in the figures, both the first pole and the second pole may be provided on the cover.

[0059] Optionally, not shown in the figures, both the first pole and the second pole may be arranged at an end of the shell in the first direction away from the cover.

[0060] 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 them. 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 make equivalent replacements for some or all of the technical features therein. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A housing structure, characterized in that: The device comprises a shell and a cover, wherein the cover is provided with an explosion-proof valve and is provided on one end of the shell in a first direction. The cover and the shell together form a closed space for accommodating an electrode group. A limiting assembly is provided on the inner wall of the housing near one end of the cover body, the limiting assembly protrudes toward the interior of the enclosed space relative to the inner wall, and the limiting assembly is provided between the cover body and the pole group; The perimeter of a figure formed by cutting the closed space with a plane perpendicular to the first direction is defined as C, and the sum of the lengths of the end of the limiting assembly facing the pole group in the circumferential direction of the closed space is defined as A; Among them, 45%≤A / C≤65%.

2. The housing structure according to claim 1, wherein: The limiting assembly includes a plurality of limiting portions, and the plurality of limiting portions are arranged at intervals along the circumferential direction.

3. The housing structure according to claim 2, wherein: End surfaces of the plurality of limiting portions on a side facing the pole group are aligned with each other in the first direction to form a limiting array.

4. The housing structure according to claim 3, wherein: The limiting assembly includes one or more limiting rows; If there are multiple spacer groups, the multiple spacer groups are spaced apart along the first direction.

5. The housing structure according to claim 4, characterized in that: The total length of the limiting assembly in the circumferential direction at one end facing the pole group is the sum of the dimensions in the circumferential direction of all limiting portions included in the one closest to the pole group among the plurality of limiting arrays.

6. The housing structure according to claim 4, characterized in that: In the circumferential direction, the limiting portions of the plurality of limiting arrays are staggered with each other.

7. The housing structure according to any one of claims 1 to 6, characterized in that: The limiting assembly is integrally connected to the inner wall of the shell.

8. The housing structure according to any one of claims 1 to 6, characterized in that: An insulating member is further included. The insulating member is arranged on a side of the cover body facing the pole group, and when the cover body and the shell are covered with each other, at least a portion of the insulating member extends into the closed space.

9. The housing structure according to claim 8, characterized in that: When the cover and the housing are covered with each other, at least a portion of the insulating member and the limiting assembly overlap with each other in the first direction.

10. A battery, characterized in that: The housing structure comprises the housing structure according to any one of claims 1 to 9.

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