Cover plate assembly and battery cell

Abstract

The utility model relates to the technical field of batteries, in particular to a cover plate assembly and a battery cell, and the cover plate assembly comprises a cover plate and an anti-explosion valve; wherein in the first preset direction, an installation through hole penetrating through the two sides of the cover plate is formed in the cover plate, the anti-explosion valve is installed in the installation through hole, and a boss arranged on the outer side of the anti-explosion valve is further formed on the side, close to the pole group of the battery cell, of the cover plate. In the cover plate assembly provided by the invention, the boss is arranged on the side, close to the pole group of the battery cell, of the cover plate, namely the inner side, and the boss can always abut against the pole group, so that the pole group is positioned, the situation that the boss moves in the first preset direction and blocks an anti-explosion valve on the cover plate is avoided, the exhaust effect during thermal runaway is ensured, and the safety and reliability of battery cell use are improved.

Description

Technical Field

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

[0002] Currently, in addition to the electrode group and electrolyte, the battery cell also contains insulating material used to protect the fixed electrode group and prevent short circuits between the electrode group and the casing or cover. However, this insulating material is generally made of polypropylene (PP), which has very limited strength and high-temperature resistance. Generally, at around 150 degrees Celsius, these fixed structures inside the battery cell melt and fail. However, the temperature at which thermal runaway occurs in the battery cell is usually far higher than the melting point of these insulating materials. At this point, only the electrode group remains inside the battery cell. Due to the melting of the insulating protective material, the gap between the electrode group and the casing increases. At this time, the electrode group has a high degree of freedom within the battery cell. As the high-temperature, high-pressure gas is vented in the direction of the explosion-proof valve, the electrode group will randomly move with the high-temperature, high-pressure gas flow, blocking the explosion-proof valve on the cover and the exhaust channel, greatly reducing the exhaust efficiency of the explosion-proof valve and the safety performance of the battery cell. Utility Model Content

[0003] The purpose of this application is to provide a cover assembly and a battery cell, which to a certain extent solves the technical problem in the prior art that the insulating material between the electrode group and the battery cell will melt due to the high temperature generated when the battery cell thermal runaways, resulting in an increase in the gap between the electrode group and the shell, and then the battery cell will easily move randomly with the high-temperature and high-pressure airflow to block the explosion-proof valve, thereby reducing the exhaust effect.

[0004] The present application provides a cover plate assembly, comprising: a cover plate and an explosion-proof valve; wherein, along a first preset direction, the cover plate is formed with mounting holes running through both sides thereof, the explosion-proof valve is installed in the mounting holes, and a boss is also formed on the side of the cover plate close to the pole group of the battery cell and arranged on the outside of the explosion-proof valve.

[0005] In the above technical solution, further, there are multiple bosses.

[0006] In any of the above technical solutions, further, the sum of the gap volumes between all the bosses is V1, and V1=S1H-S2HN; the total volume increased in the first preset direction after the bosses are added to the cover plate is V, and V=S1H;

[0007] Among them, 1.0m≤V1 / V≤2.5m; the projected area of the cover plate along the first preset direction is S1; the projected area of a single boss along the first preset direction is S2; the height of the boss relative to the cover plate in the first preset direction is H; the number of bosses is N; and m is the coefficient of the designed opening area of the explosion-proof valve.

[0008] In any of the above technical solutions, further, the boss is cylindrical, and the diameter of the boss along the cross section perpendicular to the first preset direction is D;

[0009] The cover plate is rectangular, and the total length of the cover plate is A, and the total width of the cover plate is B; wherein S1 = AB, S2 = πD 2 / 4.

[0010] In any of the above technical solutions, further, along the length direction of the cover plate, at least two opposite outer sides of the explosion-proof valve are provided with the bosses.

[0011] In any of the above technical solutions, further, there are multiple bosses provided on at least one outer side of the explosion-proof valve.

[0012] In any of the above technical solutions, further, the plurality of bosses provided on the same outer side of the explosion-proof valve are arranged in a square array.

[0013] In any of the above technical solutions, further, the plurality of bosses provided on the same outer side of the explosion-proof valve are arranged in a square array along the length direction and the width direction of the cover plate.

[0014] In any of the above technical solutions, further, the length direction of the explosion-proof valve is the same as the width direction of the cover plate, and the width direction of the explosion-proof valve is the same as the length direction of the cover plate.

[0015] The present application also provides a battery cell, comprising the cover plate assembly described in any of the above technical solutions, and thus having all the beneficial technical effects of the cover plate assembly, which will not be repeated here.

[0016] Compared with the prior art, the present invention has the following advantages:

[0017] In the cover plate assembly provided in the present application, a boss is provided on the side of the cover plate close to the pole group of the battery cell, that is, on the inner side. The boss can always rest against the pole group, thereby positioning the pole group to prevent movement along the first preset direction and blocking the explosion-proof valve on the cover plate, thereby ensuring the exhaust effect during thermal runaway and improving the safety and reliability of the battery cell.

[0018] Moreover, the ratio V1 / V of the sum of the gap volumes V1 between all the bosses and the total volume V increased in the first preset direction after the bosses are added to the cover plate is taken in the range of 1.0m-2.5m, ensuring that the ventilation volume of the entire exhaust path between the gas generated in various parts of the battery cell and the explosion-proof valve is matched with the gas production volume / gas production rate of the battery cell, thereby greatly improving the proportion of directional opening of the explosion-proof valve when thermal runaway occurs in the battery cell, thereby improving the safety performance of the battery cell. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] 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.

[0020] Figure 1 A schematic structural diagram of the cover assembly provided in an embodiment of the present application.

[0021] Reference numerals:

[0022] 1-cover plate, 2-boss, 3-explosion-proof valve. DETAILED DESCRIPTION

[0023] 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.

[0024] 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.

[0025] 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.

[0026] 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.

[0027] 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.

[0028] Refer to the following Figure 1 The present invention describes a cover assembly and a battery cell according to some embodiments of the present application.

[0029] Example 1

[0030] See also Figure 1 As shown, an embodiment of the present application provides a cover plate assembly, comprising: a cover plate 1 and an explosion-proof valve 3; wherein, along a first preset direction, the cover plate 1 is formed with mounting holes running through both sides thereof, the explosion-proof valve 3 is installed in the mounting holes, and a boss 2 is also formed on the side of the cover plate 1 close to the pole group of the battery cell and arranged on the outside of the explosion-proof valve 3.

[0031] According to the structure described above, in the present application, a boss 2 is provided on the inner side of the cover plate 1 close to the pole group of the battery cell. The boss 2 can always rest against the pole group, thereby positioning the pole group to avoid movement along the first preset direction and blocking the explosion-proof valve 3 on the cover plate 1, thereby ensuring the exhaust effect during thermal runaway and improving the safety and reliability of the battery cell.

[0032] Further, preferably, the first preset direction is the thickness direction of the cover plate 1. Of course, it is not limited thereto.

[0033] In this embodiment, preferably, Figure 1 As shown, there are multiple bosses 2 .

[0034] According to the structure described above, it can be seen that designing multiple bosses 2 can achieve better positioning effect on the pole group. Of course, it is not limited to this. The number of bosses 2 is not limited to multiple, but can also be one, etc., which is selected according to actual needs.

[0035] In this embodiment, preferably, Figure 1 As shown, the sum of the gap volumes between all bosses 2 is V1, and V1=S1H-S2HN; the total volume added to the cover plate 1 in the first preset direction after the bosses 2 are added is V, and V=S1H;

[0036] The projection area of the cover plate 1 along the first preset direction is S1; the projection area of a single boss 2 along the first preset direction is S2; the height of the boss 2 relative to the cover plate 1 in the first preset direction is H; and the number of bosses 2 is N.

[0037] Further, preferably, the boss 2 is cylindrical, and the diameter of the boss 2 along the cross section perpendicular to the first preset direction is D;

[0038] The cover plate 1 is rectangular, and the total length of the cover plate 1 is A, and the total width of the cover plate 1 is B; wherein S1 = AB, S2 = πD 2 / 4, on this basis it can be deduced that V1=S1H-πD 2 HN / 4;

[0039] Furthermore, 1.0m≤V1 / V≤2.5m, where m is the coefficient of the designed opening area of the explosion-proof valve 3 .

[0040] According to the structure described above, it can be seen that the value of V1 / V is set within the above-mentioned range of 1.0mm-2.5mm to ensure that the ventilation volume of the entire exhaust path between the gas generated in various parts of the battery cell and the explosion-proof valve 3 matches the gas production volume / gas production rate of the battery cell, thereby greatly improving the proportion of directional opening of the explosion-proof valve 3 when thermal runaway occurs in the battery cell, thereby improving the safety performance of the battery cell.

[0041] It should be noted that V1 / V is not limited to the above-mentioned range of 1.0mm-2.5mm, but can also be less than 1.0mm or greater than 2.5mm, depending on actual needs.

[0042] In addition, it should be noted that the boss 2 is not limited to a cylindrical shape, so the cross-sectional area S2 of the boss 2 along the first preset direction is no longer calculated according to πD 2 / 4 is calculated, but a specific calculation is made based on the specific shape of the aforementioned cross section. For example, the boss 2 can also be prism-shaped, etc., then the area S2 of the cross section of the boss 2 along the first preset direction perpendicular to the first preset direction is calculated accordingly according to the area of the polygon.

[0043] In this embodiment, preferably, Figure 1 As shown, along the length direction a of the cover plate 1 , bosses 2 are provided on two opposite outer sides of the explosion-proof valve 3 .

[0044] According to the structure described above, bosses 2 are provided on both opposite outer sides of the explosion-proof valve 3 in the length direction a of the cover plate 1, which fully utilizes the ample space in the length direction a of the cover plate 1 and helps to improve the positioning effect of the electrode group.

[0045] It should be noted that: it is not limited to the aforementioned "only along the length direction a of the cover plate 1, the bosses 2 are provided on the two opposite outer sides of the explosion-proof valve 3", but the boss 2 can also be provided on only one outer side of the explosion-proof valve 3 along the length direction a of the cover plate 1, or the boss 2 can be provided on at least one outer side of the explosion-proof valve 3 along the width direction b of the cover plate 1, etc., and the specific selection is based on actual needs.

[0046] In this embodiment, preferably, Figure 1 As shown, along the length direction a of the cover plate 1 , there are multiple bosses 2 arranged on both outer sides of the explosion-proof valve 3 .

[0047] As can be seen from the structure described above, multiple bosses 2 are provided on both sides of the explosion-proof valve 3, which improves the positioning of the electrode assembly at various locations, making the electrode assembly more stable and preventing it from moving and clogging the explosion-proof valve 3. Of course, this is not limited to this, and the number of bosses 2 provided on both sides of the explosion-proof valve 3 can also be one, etc., depending on actual needs.

[0048] Furthermore, preferably, the multiple bosses 2 on both sides of the explosion-proof valve 3 are symmetrically arranged, which facilitates processing and manufacturing, and ensures consistent positioning of the electrode groups on both sides of the explosion-proof valve 3. Of course, the multiple bosses 2 on both sides of the explosion-proof valve 3 can also be asymmetrically arranged, depending on actual needs.

[0049] In this embodiment, preferably, Figure 1 As shown, multiple bosses 2 provided on the same outer side of the explosion-proof valve 3 are arranged in a square array.

[0050] According to the structure described above, arranging the multiple bosses 2 on the same outer side of the explosion-proof valve 3 in a square array is more regular, convenient for processing and manufacturing, and has a better positioning effect on the electrode group.

[0051] It should be noted that the multiple bosses 2 provided on the same outer side of the explosion-proof valve 3 are not limited to being arranged in a square array, but can also be arranged in a circular array, or not in an array but randomly.

[0052] In this embodiment, preferably, Figure 1 As shown, the plurality of bosses 2 provided on the same outer side of the explosion-proof valve 3 are arranged in a square array along the length direction a and the width direction of the cover plate 1 .

[0053] According to the structure described above, the multiple bosses 2 located on the same outer side of the explosion-proof valve 3 are arranged in a square array along the length direction a and the width direction of the cover plate 1. This can make full use of the space on the cover plate 1, arrange more bosses 2, improve the positioning effect of the electrode group, and effectively prevent the electrode group from moving and clogging the explosion-proof valve 3.

[0054] It should be noted that when multiple bosses 2 placed on the same outer side of the explosion-proof valve 3 are arranged in a square array, the arrangement direction is not limited to the length direction a of the cover plate 1 and the width direction b of the cover plate 1, but can also be other squares, which can be selected according to actual needs.

[0055] In this embodiment, preferably, Figure 1 As shown, the length direction of the explosion-proof valve 3 is the same as the width direction b of the cover plate 1 , and the width direction of the explosion-proof valve 3 is the same as the length direction a of the cover plate 1 .

[0056] According to the structure described above, the explosion-proof valve 3 is arranged along the width direction b of the cover plate 1 to reduce the space occupied in the length direction, which can effectively avoid the opening of the pole, the plastic and the injection hole.

[0057] It should be noted that: it is not limited to the above-mentioned "the length direction of the explosion-proof valve 3 is the same as the width direction b of the cover plate 1, and the width direction of the explosion-proof valve 3 is the same as the length direction a of the cover plate 1". The length direction of the explosion-proof valve 3 can also be the same as the length direction a of the cover plate 1, and the width direction of the explosion-proof valve 3 is the same as the width direction b of the cover plate 1, or the length direction of the explosion-proof valve 3 forms an acute angle or an obtuse angle with the length direction a of the cover plate 1, and the width direction of the explosion-proof valve 3 forms an acute angle or an obtuse angle with the width direction b of the cover plate 1. The specific selection is based on actual needs.

[0058] In summary, in the cover plate assembly provided in this embodiment, the boss 2 structure is symmetrically and evenly designed on both sides of the explosion-proof valve 3 on the cover plate 1, such as a plain aluminum sheet, and the boss 2 structure is designed to meet 1.0m≤V1 / V≤2.5m, ensuring that the entire exhaust path from the gas generated in various parts of the battery cell to the explosion-proof valve 3 can meet the ventilation volume that matches the gas production volume / gas production rate of the battery cell, thereby greatly improving the proportion of directional opening of the explosion-proof valve 3 when thermal runaway occurs in the battery cell, and improving the safety performance of the battery cell.

[0059] Example 2

[0060] Embodiment 2 of the present application further provides a battery cell, comprising the cover plate assembly described in the above-mentioned embodiment 1, and thus has all the beneficial technical effects of the cover plate assembly, and the same technical features and beneficial effects are not repeated here.

[0061] It should be noted that: along the first preset direction, an opening is formed at one end of the shell, and the aforementioned cover assembly is installed only at this open end, or along the first preset direction, openings are formed at both ends of the shell, and the aforementioned cover assembly is installed only at this open end or at both open ends at the same time, and the specific design is based on actual needs.

[0062] 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 cover plate assembly, characterized in that: include: A cover plate and an explosion-proof valve; wherein, along a first preset direction, the cover plate is formed with mounting holes running through both sides thereof, the explosion-proof valve is installed in the mounting holes, and a boss is also formed on the side of the cover plate close to the pole group of the battery cell and arranged on the outside of the explosion-proof valve.

2. The cover plate assembly according to claim 1, wherein: There are multiple bosses.

3. The cover plate assembly according to claim 1, wherein: The sum of the gap volumes between all the bosses is V1, and V1=S1H-S2HN; the total volume added to the cover plate in the first preset direction after the bosses are added is V, and V=S1H; Among them, 1.0m≤V1 / V≤2.5m; the projected area of the cover plate along the first preset direction is S1; the projected area of a single boss along the first preset direction is S2; the height of the boss relative to the cover plate in the first preset direction is H; the number of bosses is N; and m is the coefficient of the designed opening area of the explosion-proof valve.

4. The cover plate assembly according to claim 3, wherein: The boss is cylindrical, and the diameter of the cross section of the boss along the vertical direction is D; The cover plate is rectangular, and the total length of the cover plate is A, and the total width of the cover plate is B; wherein S1 = AB, S2 = πD 2 / 4.

5. The cover plate assembly according to claim 1, wherein: Along the length direction of the cover plate, at least two opposite outer sides of the explosion-proof valve are provided with the bosses.

6. The cover plate assembly according to claim 5, characterized in that: There are multiple bosses arranged on at least one outer side of the explosion-proof valve.

7. The cover plate assembly according to claim 6, wherein: The plurality of bosses disposed on the same outer side of the explosion-proof valve are arranged in a square array.

8. The cover plate assembly according to claim 7, wherein: The plurality of bosses disposed on the same outer side of the explosion-proof valve are arranged in a square array along the length direction and the width direction of the cover plate.

9. The cover plate assembly according to claim 1, wherein: The length direction of the explosion-proof valve is the same as the width direction of the cover plate, and the width direction of the explosion-proof valve is the same as the length direction of the cover plate.

10. A battery cell, characterized in that: A cover plate assembly comprising the cover plate assembly according to any one of claims 1 to 9.

Images