Cover plate structure and battery

Abstract

The utility model belongs to the technical field of batteries, and discloses a cover plate structure and a battery, the cover plate structure comprises a top cover plate and a support plate, the top cover plate is provided with an anti-explosion valve and a protruding part, and the protruding part and the anti-explosion valve are arranged at an interval; the supporting plate is connected with the protruding part so that an exhaust channel can be formed between the supporting plate and the top cover plate, a first exhaust hole and a second exhaust hole are formed in the supporting plate, and the first exhaust hole and the second exhaust hole are both communicated with the exhaust channel; the projection of the second exhaust hole in the first direction at least partially coincides with the projection of the anti-explosion valve in the first direction. Thus, the supporting plate is arranged on the protruding part, so that an exhaust channel is formed between the supporting plate and the top cover plate, high-temperature and high-pressure gas can enter the exhaust channel through the first exhaust hole and the second exhaust hole when the battery is in thermal runaway, and the exhaust effect of the anti-explosion valve is improved; the supporting plate can limit the end part of the pole group, so that the pole group is prevented from moving and shielding the anti-explosion valve, and the safety performance of the battery is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of batteries, in particular to a cover plate structure and a battery. Background Art

[0002] A battery is a device that converts chemical energy into electrical energy. Lithium-ion batteries have become the representative of modern high-performance batteries due to their high operating voltage, high specific energy, large capacity, low self-discharge, good cycle performance, long service life, light weight and small size.

[0003] Long-cell lithium-ion batteries are usually designed with tabs on both sides, that is, tabs with opposite polarity are respectively arranged at both ends of the battery cell. Long-cell lithium-ion batteries include a cover, a shell, a pole group, an electrolyte, etc. The shell and the cover are welded to form a closed space with a certain mechanical strength. The pole group is arranged in the closed space and protected by the shell and the cover. The cover is respectively arranged at both ends of the shell. The tabs connected at both ends of the pole group are respectively fixed to the pole base on the corresponding cover by laser welding to achieve electrical connection with the external circuit. The side wall of the cover facing the pole group is provided with a plastic part, which is used to fix and insulate the pole group; the cover is also provided with an explosion-proof valve. When a short circuit occurs inside the battery and thermal runaway occurs, the gas can be discharged to the outside through the explosion-proof valve.

[0004] However, since plastic parts are usually made of PP (polypropylene), the strength of the plastic parts is low and the heat resistance is poor. When thermal runaway occurs inside the battery, the plastic parts may melt and fail due to the high temperature, and lose their fixation to the electrode group, allowing the ends of the electrode group to move freely. When the high-temperature and high-pressure gas is discharged toward the explosion-proof valve, the electrode group is prone to move under the action of the high-temperature and high-pressure airflow, and may block the explosion-proof valve and the airflow channel, reducing the exhaust effect of the explosion-proof valve and the safety performance of the battery cell. The ends of the electrode group may collide with the shell during the movement, which may also cause damage to the electrode group, thereby reducing the safety performance of the battery cell. Utility Model Content

[0005] The purpose of the utility model is to provide a cover plate structure and a battery to solve the problem that when thermal runaway occurs inside the battery, the explosion-proof valve and the air flow channel are blocked, resulting in poor exhaust effect and easy damage and deformation of the electrode group.

[0006] To achieve this purpose, the present invention adopts the following technical solutions:

[0007] In a first aspect, a cover plate structure includes: a top cover plate, on which an explosion-proof valve and a raised portion are provided, and the raised portion is spaced apart from the explosion-proof valve; a support plate, which is connected to the raised portion to form an exhaust channel between the support plate and the top cover plate, and a first exhaust hole and a second exhaust hole are provided on the support plate, and the first exhaust hole and the second exhaust hole are both connected to the exhaust channel; the projection of the second exhaust hole in the first direction at least partially overlaps with the projection of the explosion-proof valve in the first direction.

[0008] Preferably, a plurality of the first exhaust holes are provided, and the plurality of the first exhaust holes are symmetrically arranged on both sides of the second exhaust hole.

[0009] Preferably, the second exhaust hole is arranged at a position corresponding to the explosion-proof valve, and the shape of the second exhaust hole is similar to that of the explosion-proof valve.

[0010] Preferably, the length direction of the protrusion is parallel to the length direction of the explosion-proof valve; and / or the length direction of the support plate is perpendicular to the length direction of the explosion-proof valve.

[0011] Preferably, the height of the protrusion ranges from 1.5 mm to 3 mm.

[0012] Preferably, the support plate is connected to a reinforcement portion, and the reinforcement portion is arranged in the second exhaust hole.

[0013] Preferably, a plurality of reinforcing parts are provided, and both ends of the reinforcing parts are respectively fixedly connected to the inner wall of the second exhaust hole.

[0014] Preferably, the cover plate structure further comprises a plastic part, which is arranged on a side of the support plate away from the top cover plate, and the plastic part is provided with a third exhaust hole, which is communicated with the exhaust channel.

[0015] Preferably, the length of the support plate is smaller than the length of the plastic part.

[0016] In a second aspect, a battery comprises a cell, a shell and the cover plate structure as described above, wherein the shell is fixedly connected to the top cover plate, and the cell is arranged in a space enclosed by the top cover plate and the shell.

[0017] Beneficial effects of the utility model:

[0018] A cover plate structure includes a top cover plate and a support plate, wherein an explosion-proof valve and a raised portion are provided on the top cover plate, and the raised portion is spaced apart from the explosion-proof valve; the support plate is connected to the raised portion to form an exhaust channel between the support plate and the top cover plate, and a first exhaust hole and a second exhaust hole are provided on the support plate, and both the first exhaust hole and the second exhaust hole are connected to the exhaust channel; the projection of the second exhaust hole in the first direction at least partially overlaps with the projection of the explosion-proof valve in the first direction.

[0019] In this way, the provision of the raised portion can form an exhaust channel between the support plate and the top cover plate, so that when the battery undergoes thermal runaway, high-temperature and high-pressure gas can enter the exhaust channel through the first exhaust hole and the second exhaust hole, and quickly converge at the explosion-proof valve, thereby improving the exhaust effect of the explosion-proof valve; after the plastic part fails to melt, the support plate can limit the end of the pole group to prevent the pole group from moving and causing obstruction of the explosion-proof valve or damage, and the projection of the second exhaust hole in the first direction at least partially overlaps with the projection of the explosion-proof valve in the first direction, which can enable the high-temperature and high-pressure gas to be quickly discharged to the explosion-proof valve, thereby improving the safety performance of the battery. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a partial structural diagram of the cover plate structure in one embodiment of the present utility model;

[0021] Figure 2 This is a partial structural diagram of the cover plate structure in one embodiment of the present utility model;

[0022] Figure 3 This is an exploded schematic diagram of the cover structure in one embodiment of the present invention;

[0023] Figure 4 It is a structural schematic diagram of the cover structure in one embodiment of the present utility model.

[0024] In the picture:

[0025] 1. Top cover plate; 11. Explosion-proof valve; 12. Raised portion; 2. Support plate; 21. First exhaust hole; 22. Second exhaust hole; 23. Reinforcement portion; 231. First portion; 232. Second portion; 3. Exhaust channel; 4. Plastic part; 41. Third exhaust hole; X, first direction. DETAILED DESCRIPTION

[0026] The present invention will be further described in detail below with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are intended only to illustrate the present invention and are not intended to limit the present invention. It should also be noted that, for ease of description, the accompanying drawings only illustrate portions relevant to the present invention, not all of its components.

[0027] In the description of this utility model, unless otherwise specified or limited, the terms "connected," "connect," and "fixed" should be understood in a broad sense. For example, they can refer to fixed connection, detachable connection, or integration; mechanical connection or electrical connection; direct connection or indirect connection through an intermediate medium; internal communication between two components or interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in this utility model based on the specific circumstances.

[0028] In the present invention, unless otherwise expressly specified or limited, a first feature being "above" or "below" a second feature may include the first and second features being in direct contact, or may include the first and second features being in contact not directly but through another feature between them. Moreover, a first feature being "above," "above," and "above" a second feature may include the first feature being directly above or obliquely above the second feature, or may simply mean that the first feature is higher in level than the second feature. A first feature being "below," "below," and "below" a second feature may include the first feature being directly below or obliquely below the second feature, or may simply mean that the first feature is lower in level than the second feature.

[0029] In the description of this embodiment, the terms "upper," "lower," "right," and other orientations or positional relationships are based on the orientations or positional relationships shown in the accompanying drawings and are intended solely for ease of description and simplified operation. 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 the present invention. Furthermore, the terms "first" and "second" are used solely for descriptive purposes and have no special meaning.

[0030] See Figure 1 and Figure 2 The utility model provides a cover plate structure, including a top cover plate 1 and a support plate 2, the top cover plate 1 is provided with an explosion-proof valve 11 and a protrusion 12, the protrusion 12 is spaced apart from the explosion-proof valve 11; the support plate 2 is connected to the protrusion 12 to form an exhaust channel 3 between the support plate 2 and the top cover plate 1, the support plate 2 is provided with a first exhaust hole 21 and a second exhaust hole 22, both of which are connected to the exhaust channel 3; the projection of the second exhaust hole 22 in the first direction X at least partially overlaps with the projection of the explosion-proof valve 11 in the first direction X.

[0031] In this embodiment, the explosion-proof valve 11 is arranged at the center position of the top cover plate 1, and the length direction of the explosion-proof valve 11 is parallel to the length direction of the top cover plate 1. The protrusion 12 is formed on the top cover plate 1 by stamping. There are multiple protrusions 12, and the protrusions 12 are conical boss structures. The multiple protrusions 12 are symmetrically arranged on both sides of the explosion-proof valve 11. One support plate 2 is provided, and the length direction of the support plate 2 is parallel to the length direction of the top cover plate 1. The support plate 2 is made of aluminum material; the first direction X is parallel to the thickness direction of the top cover plate 1.

[0032] In this way, the support plate 2 is fixedly arranged on the raised portion 12, so that an exhaust channel 3 can be formed between the support plate 2 and the top cover plate 1. When thermal runaway occurs inside the battery, high-temperature and high-pressure gas can enter the exhaust channel 3 through the first exhaust hole 21 and the second exhaust hole 22, and the high-temperature and high-pressure gas is gathered at the explosion-proof valve 11, thereby improving the exhaust effect of the explosion-proof valve 11; after the plastic part 4 melts and fails during thermal runaway, the support plate 2 can limit the end of the electrode group to prevent the end of the electrode group from moving under the action of the airflow and blocking the exhaust valve and the exhaust channel 3, and can also prevent damage to the electrode group when it moves. The projection of the second exhaust hole 22 in the first direction X at least partially overlaps with the projection of the explosion-proof valve 11 in the first direction X, which can enable the high-temperature and high-pressure gas to be quickly discharged to the explosion-proof valve 11, thereby improving the safety performance of the battery.

[0033] See Figure 1 In some embodiments, a plurality of first exhaust holes 21 are provided, and the plurality of first exhaust holes 21 are symmetrically arranged on both sides of the second exhaust hole 22. In this embodiment, a single second exhaust hole 22 is provided, and the second exhaust hole 22 is arranged at the center of the support plate 2. That is, when the support plate 2 is assembled onto the raised portion 12, the second exhaust hole 22 is coaxially arranged with the explosion-proof valve 11 in the first direction X.

[0034] In this way, when the battery has thermal runaway, the gas can be quickly discharged into the exhaust channel 3 through the first exhaust hole 21 and the second exhaust hole 22, and converge at the explosion-proof valve 11, thereby improving the exhaust effect of the explosion-proof valve 11. The symmetrical arrangement of multiple first exhaust holes 21 on both sides of the second exhaust hole 22 can make the structural strength of each part of the support plate 2 more uniform, thereby avoiding local deformation of the support plate 2 and damage to the electrode group when the battery has thermal runaway, thereby improving the safety performance of the battery.

[0035] It is understandable that the number and location of the first exhaust holes 21 and the second exhaust holes 22 can be flexibly adjusted, and no further details are given here.

[0036] See Figure 1 In some embodiments, the second exhaust hole 22 is provided at a position corresponding to the explosion-proof valve 11 , and a shape of the second exhaust hole 22 is similar to that of the explosion-proof valve 11 .

[0037] In this way, when thermal runaway occurs in the battery, the end of the electrode group can be supported by the support plate 2 after the plastic part 4 melts and fails, thereby limiting the end of the electrode group, preventing the electrode group from blocking the explosion-proof valve 11 due to movement, improving the exhaust effect of the explosion-proof valve 11, and protecting the end of the electrode group, reducing damage and deformation of the electrode group, and improving the safety performance of the battery.

[0038] It is understandable that the shape of the second exhaust hole 22 can also be circular, square, etc., and is not limited to a shape similar to the explosion-proof valve 11. The shape of the second exhaust hole 22 can be flexibly adjusted according to actual needs, and this embodiment does not limit it here.

[0039] See Figure 1 and Figure 2 In some embodiments, the length direction of the protrusion 12 is parallel to the length direction of the explosion-proof valve 11, and the length direction of the support plate 2 is perpendicular to the length direction of the explosion-proof valve 11. In other words, the length direction of the protrusion 12 is perpendicular to the length direction of the support plate 2, and the two ends of the support plate 2 are respectively welded to the protrusions 12 provided at the two ends of the top cover plate 1.

[0040] In this way, more space can be provided on the side of the protrusion 12 facing the support plate 2 to increase the area of ​​the support plate 2, so that the support plate 2 has sufficient structural strength to support the plastic part 4 and the electrode group, thereby preventing the electrode group end from losing its limit and moving when the battery thermal runaway occurs, making it difficult for the electrode group to block the explosion-proof valve 11, and improving the exhaust effect of the explosion-proof valve 11.

[0041] It can be understood that the connection between the support plate 2 and all the protrusions 12 can be fixed by welding, or it can be simply overlapped with the protrusions 12 except those located at the two ends of the top cover plate 1. The specific connection method can be flexibly adjusted to limit the relative position of the support plate 2 and the protrusions 12.

[0042] See Figure 2 In some embodiments, the height of the protrusion 12 ranges from 1.5 mm to 3 mm. For example, the height of the protrusion 12 can be 1.5 mm, 1.7 mm, 2 mm, 2.5 mm, 2.7 mm, or 3 mm.

[0043] It is understandable that the height of the protrusion 12 can be flexibly adjusted according to the specifications and dimensions of the top cover plate 1, and this embodiment does not limit this.

[0044] See Figure 1 In some embodiments, the support plate 2 is connected to a reinforcement portion 23 , and the reinforcement portion 23 is disposed in the second exhaust hole 22 .

[0045] In this way, the reinforcement part 23 can enhance the structural strength of the second exhaust hole 22, making the support plate 2 less likely to deform, and allowing the gas to pass smoothly through the second exhaust hole 22 and enter the exhaust channel 3. When the battery has thermal runaway, the support plate 2 can limit the end of the electrode group, and the reinforcement part 23 can prevent the electrode group from blocking the explosion-proof valve 11, thereby improving the exhaust effect of the explosion-proof valve 11, avoiding damage and deformation of the electrode group, and improving the safety performance of the battery.

[0046] See Figure 1 In some embodiments, a plurality of reinforcing portions 23 are provided, and both ends of the reinforcing portion 23 are fixedly connected to the inner wall of the second exhaust hole 22. The reinforcing portion 23 includes a first portion 231 whose length direction is parallel to the length direction of the support plate 2 and a second portion 232 arranged perpendicular to the first portion 231.

[0047] In this way, by setting the first part 231 and the second part 232 perpendicular to each other, the structural strength of the second exhaust hole 22 of the reinforcement part 23 can be further improved, so that the first part 231 and the second part 232 limit the end of the pole group, preventing the pole group from moving under the action of airflow and blocking the explosion-proof valve 11, thereby reducing deformation and damage of the pole group.

[0048] It is understandable that the first portion 231 and the second portion 232 may also be arranged at an acute angle and are not limited to being arranged vertically, which will not be elaborated here.

[0049] See Figure 3 and Figure 4 In some embodiments, the cover plate structure further includes a plastic part 4 , which is arranged on the side of the support plate 2 facing away from the top cover plate 1 , and the plastic part 4 is provided with a third exhaust hole 41 , which is connected to the exhaust channel 3 .

[0050] There are multiple third exhaust holes 41 , and the multiple third exhaust holes 41 are spaced apart along the length direction of the plastic part 4 .

[0051] In this way, the plastic part 4 can limit the end of the electrode group under normal conditions. When the battery is thermally runaway, high-temperature and high-pressure gas can enter the exhaust channel 3 through the third exhaust hole 41, thereby improving the exhaust efficiency of the exhaust valve, avoiding heat accumulation in the plastic part 4, and reducing the possibility of melting failure of the plastic part 4.

[0052] It is understandable that the shape, number and location of the third exhaust holes 41 can be flexibly adjusted so as to enable the gas to be discharged into the exhaust channel 3 through the third exhaust holes 41 , and this embodiment does not limit this.

[0053] See Figure 3In some embodiments, the length of the support plate 2 is less than the length of the plastic part 4. In this embodiment, the explosion-proof valve 11, the support plate 2, and the plastic part 4 are coaxially arranged along the first direction X, and the length of the plastic part 4 is adapted to the height of the battery cell.

[0054] In this way, under normal conditions, the plastic part 4 can provide good support for the end of the electrode group to prevent the end of the electrode group from moving in the shell. When the battery thermal runaway causes the plastic part 4 to melt and fail, due to the small length of the support plate 2, there is enough space for the high-temperature and high-pressure gas to flow to the explosion-proof valve 11, thereby improving the exhaust efficiency, thereby improving the exhaust effect of the explosion-proof valve 11 and the safety performance of the battery.

[0055] It is understandable that the length of the support plate 2 may also be equal to or greater than the length of the plastic part 4 , and this embodiment does not limit this.

[0056] See Figure 3 The utility model also provides a battery, including a battery cell (not shown in the figure), a shell (not shown in the figure) and a cover structure, the shell is fixedly connected to the top cover plate 1, and the battery cell is arranged in the space enclosed by the top cover plate 1 and the shell.

[0057] There are two cover plate structures, which are respectively arranged at the two ends of the battery cell.

[0058] Obviously, the above-described embodiments of the present invention are merely examples for the purpose of clearly illustrating the present invention and are not intended to limit the manner in which the present invention is to be implemented. A person skilled in the art would be able to make various obvious changes, readjustments, and substitutions without departing from the scope of protection of the present invention. It is not necessary and impossible to enumerate all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the claims of the present invention.

Claims

1. A cover plate structure, characterized in that: include: A top cover plate (1), wherein an explosion-proof valve (11) and a raised portion (12) are provided on the top cover plate (1), and the raised portion (12) is spaced apart from the explosion-proof valve (11); A support plate (2), the support plate (2) being connected to the raised portion (12) so as to form an exhaust passage (3) between the support plate (2) and the top cover plate (1), the support plate (2) being provided with a first exhaust hole (21) and a second exhaust hole (22), the first exhaust hole (21) and the second exhaust hole (22) both being in communication with the exhaust passage (3); The projection of the second exhaust hole (22) in the first direction (X) at least partially overlaps with the projection of the explosion-proof valve (11) in the first direction (X).

2. The cover plate structure according to claim 1, characterized in that: A plurality of the first exhaust holes (21) are provided, and the plurality of the first exhaust holes (21) are symmetrically arranged on both sides of the second exhaust hole (22).

3. The cover plate structure according to claim 1, characterized in that: The second exhaust hole (22) is arranged at a position corresponding to the explosion-proof valve (11), and the shape of the second exhaust hole (22) is similar to that of the explosion-proof valve (11).

4. The cover plate structure according to claim 1, characterized in that: The length direction of the protrusion (12) is parallel to the length direction of the explosion-proof valve (11); and / or the length direction of the support plate (2) is perpendicular to the length direction of the explosion-proof valve (11).

5. The cover plate structure according to any one of claims 1 to 4, characterized in that: The height of the protrusion (12) ranges from 1.5 mm to 3 mm.

6. The cover plate structure according to any one of claims 1 to 4, characterized in that: The support plate (2) is connected to a reinforcement portion (23), and the reinforcement portion (23) is arranged in the second exhaust hole (22).

7. The cover plate structure according to claim 6, characterized in that: A plurality of reinforcing parts (23) are provided, and both ends of the reinforcing parts (23) are respectively fixedly connected to the inner wall of the second exhaust hole (22).

8. The cover plate structure according to any one of claims 1 to 4, characterized in that: The cover plate structure further comprises a plastic part (4), the plastic part (4) being arranged on a side of the support plate (2) facing away from the top cover plate (1), the plastic part (4) being provided with a third exhaust hole (41), the third exhaust hole (41) being in communication with the exhaust channel (3).

9. The cover plate structure according to claim 8, characterized in that: The length of the support plate (2) is smaller than the length of the plastic part (4).

10. A battery, characterized in that: It comprises a battery cell, a shell and a cover plate structure according to any one of claims 1 to 9, wherein the shell is fixedly connected to the top cover plate (1), and the battery cell is arranged in a space enclosed by the top cover plate (1) and the shell.

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