Top cover assembly, battery, energy storage device and electric equipment

Abstract

The utility model discloses a top cover assembly, a battery, an energy storage device and electric equipment. The top cover assembly comprises a top cover and a cover cap. The top cover comprises a first face and a second face which are opposite. The top cover is provided with a through hole penetrating through the first face and the second face. The cap is arranged on the side, where the first face is located, of the top cover, the cap protrudes out of the first face, a containing cavity is defined by the cap and the top cover, the cap covers and seals the through hole and comprises an anti-explosion area and other areas, and the thickness a of the anti-explosion area is smaller than the thickness b of the other areas.

Description

Technical Field

[0001] The present application relates to the technical field of batteries, and particularly to a top cover assembly, a battery, an energy storage device, and an electrical equipment. Background Art

[0002] Currently, batteries are widely used in fields such as mobile phones, computers, electric vehicles, and energy storage. When a battery fails, heat is generated inside the battery, resulting in an increase in the internal air pressure of the battery. If no safety device is provided, the battery will explode. Currently, safety devices (usually explosion-proof valves) are generally provided on the cover plate of the battery. Moreover, the capacity and energy density of the battery are increasing day by day. Correspondingly, the total amount of gas generated inside the battery per unit time will also increase.

[0003] Although traditional batteries are provided with explosion-proof valves, due to the inclusion of various structures inside the battery and less remaining internal space, even if the battery has severely expanded due to the extrusion of a large amount of gas inside, the gas flow path is blocked by the internal structure of the battery, and the gas cannot flow to the explosion-proof valve to break through the explosion-proof valve. Summary of the Invention

[0004] The present application provides a top cover assembly, a battery, an energy storage device, and an electrical equipment.

[0005] In a first aspect, the present application provides a top cover assembly. The top cover assembly includes a top cover and a cap. The top cover includes a first surface and a second surface facing away from each other. The top cover is provided with a through hole penetrating through the first surface and the second surface. The cap is disposed on one side where the first surface of the top cover is located. The cap protrudes from the first surface and encloses a receiving cavity with the top cover. The cap covers and closes the through hole. The cap includes an explosion-proof area and other areas, and the thickness a of the explosion-proof area is less than the thickness b of the other areas.

[0006] In some embodiments, the cap includes a top portion and a side portion. The side portion extends from the periphery of the top portion and is connected to the top cover. The side portion surrounds the through hole. The top portion is away from and covers the through hole. The explosion-proof area is disposed on the top portion.

[0007] In some embodiments, the side portion is located between the top portion and the top cover, and the included angle between the top portion and the side portion is an obtuse angle.

[0008] In some embodiments, the ratio S1 / S2 of the area S1 of the through hole to the area S2 of the top cover satisfies: 1 / 2 ≤ S1 / S2 ≤ 4 / 5.

[0009] In some embodiments, the first surface is provided with a positioning groove surrounding the through hole. The end of the side portion away from the top portion protrudes and extends towards the outside of the central axis of the cap to form a convex edge, and the convex edge is installed in the positioning groove.

[0010] In some embodiments, when the explosion-proof area is under a pressure greater than or equal to 0.15 Mpa, the explosion-proof area opens and connects the accommodating cavity (131) with the outside.

[0011] In some embodiments, the thickness b of the side portion satisfies: 0.2 mm ≤ b ≤ 4.0 mm.

[0012] In some embodiments, the height H of the cap satisfies: 2 mm ≤ H ≤ 50 mm.

[0013] In some embodiments, the cross-section of the cap intercepted by a plane parallel to the first surface is circular, elliptical or polygonal; and / or, the cap is a metal cap.

[0014] In some embodiments, the explosion-proof area is provided with a scoring groove, and the value range of the thickness c of the top at the scoring groove is [0.2 mm, 0.7 mm].

[0015] In some embodiments, the top cover assembly further includes a terminal post and a connecting piece. The terminal post penetrates through the top cover. The connecting piece is disposed on the side where the second surface of the top cover is located and is electrically connected to the terminal post. At least part of the structure of the connecting piece passes through the through hole and extends into the accommodating cavity.

[0016] In a second aspect, the present application provides a battery. The battery includes the top cover assembly according to any one of the above embodiments.

[0017] In some embodiments, the battery further includes a housing and an electric core. The housing is provided with an opening, the top cover assembly is installed on the housing and closes the opening. The electric core is accommodated in the housing, and the tab of the electric core is electrically connected to the connecting piece of the top cover assembly.

[0018] In some embodiments, the thickness a of the top and the thickness M of the housing satisfy: a ≤ M; and / or, the thickness M of the housing satisfies: M ≤ 4 mm.

[0019] In a third aspect, the present application provides an energy storage device, and the energy storage device includes the battery according to any one of the above embodiments.

[0020] In a fourth aspect, the present application provides an electrical equipment, and the electrical equipment includes the energy storage device according to any one of the above embodiments.

[0021] In the top cover assembly, battery, energy storage device, and electrical equipment of the present application, the cap and the top cover enclose a receiving cavity. The receiving cavity can be communicated with the inside of the battery through a through hole, providing additional space inside the battery, storing some of the gas generated inside the battery, and preventing the battery from bulging rapidly. The receiving cavity can also serve as a gas flow path, guiding the gas to converge at the cap. The thickness of the explosion-proof area is less than that of other areas, so the explosion-proof area is more easily opened. After reaching a certain pressure, the explosion-proof area is ruptured by the gas, enabling the receiving cavity to communicate with the outside world, realizing the directional exhaust of gas from the receiving cavity to the explosion-proof area, and improving the safety of battery use. At the same time, since the receiving cavity can converge and concentrate the gas, the cap can carry more gas while allowing the explosion-proof area to be broken through at a lower pressure, improving the sensitivity of the explosion-proof area and reducing the probability of the battery exploding due to excessive bulging.

[0022] Additional aspects and advantages of the present application will be given in part in the following description, become apparent in part from the following description, or be learned through the practice of the present application. Brief Description of the Drawings

[0023] The above and / or additional aspects and advantages of the present application will become apparent and be readily understood from the following description of the embodiments in conjunction with the accompanying drawings, where:

[0024] Figure 1 is a three-dimensional assembly schematic diagram of a partial structure of a battery in some embodiments of the present application;

[0025] Figure 2 is Figure 1 a three-dimensional exploded schematic diagram of a partial structure of the battery in;

[0026] Figure 3 is Figure 1 a three-dimensional structure schematic diagram of the cap of the battery in;

[0027] Figure 4 is Figure 1 a cross-sectional schematic diagram of a partial structure of the battery in;

[0028] Figure 5 is Figure 3 a cross-sectional schematic diagram of the cap in;

[0029] Figure 6 is a three-dimensional exploded schematic diagram of an energy storage device in some embodiments of the present application;

[0030] Figure 7 is a schematic diagram of the structure of an electrical equipment in some embodiments of the present application.

[0031] Description of the Main Element Numbers:

[0032] Electrical equipment 10000, energy storage device 1000, battery 100; box body 300; box cover 301; box body 303;

[0033] Top cover assembly 10; top cover 11; first surface 111; positioning groove 1111; second surface 113; through hole 115; cap 13; accommodating cavity 131; top 133; explosion-proof area 1331; scoring groove 13311; other area 1332; inner surface 1333; outer surface 1335; side part 135; inner side surface 1353; outer side surface 1355; flange 137; terminal post 15; adapter plate 16; housing 30; battery cell 50; tab 51. Detailed implementation manners

[0034] In the description of the present application, some of the disclosed content has been correspondingly shown in the drawings, where the same or similar reference numerals throughout indicate the same or similar elements or elements having the same or similar functions. The content described below by referring to the drawings is exemplary and is only used to explain the present application and cannot be construed as a limitation to the present application.

[0035] In the description of the present application, many different contents or examples are disclosed to implement different structures of the present application. To simplify the disclosure of the present application, the components and settings of specific examples are described below. Of course, they are only examples and are not intended to limit the present application.

[0036] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance or implicitly indicating the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more features. In the description of the present application, the meaning of "a plurality" is two or more, unless otherwise specifically defined.

[0037] In the description of the present application, it should be understood that the terms used to indicate the orientation or positional relationship (such as "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc.) are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and facilitating the understanding of the corresponding implementation manners, rather than indicating or implying that the indicated device or element must have a specific orientation, be constructed and operated in a specific orientation. Therefore, the terms used to indicate the orientation or positional relationship cannot be construed as a limitation to the present application.

[0038] In the description of the present application, unless otherwise clearly defined and limited, the first feature being "on" or "under" the second feature may include direct contact between the first and second features, or may include the first and second features not being in direct contact but in contact through additional features therebetween. Moreover, the first feature being "above", "over" and "on top of" the second feature includes the first feature being directly above and obliquely above the second feature, or merely indicating that the first feature has a higher horizontal height than the second feature. The first feature being "under", "beneath" and "underneath" the second feature includes the first feature being directly below and obliquely below the second feature, or merely indicating that the first feature has a lower horizontal height than the second feature.

[0039] In the description of the present application, it should be noted that, unless otherwise clearly defined and limited, the terms "mounted", "connected" and "coupled" should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral connection. It may be a mechanical connection or an electrical connection. It may be directly connected or indirectly connected through an intermediate medium, and may be the internal communication of two components or the interaction relationship between two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to specific circumstances.

[0040] Please refer to Figure 1 and Figure 2 , the present application provides a battery 100. The battery 100 includes a top cover assembly 10.

[0041] The top cover assembly 10 includes a top cover 11 and a cap 13. The top cover 11 includes a first surface 111 and a second surface 113 facing away from each other. The top cover 11 is provided with a through hole 115 penetrating the first surface 111 and the second surface 113. The cap 13 is disposed on the side where the first surface 111 of the top cover 11 is located. The cap 13 protrudes from the first surface 111 and encloses a receiving cavity 131 with the top cover 11. The cap 13 covers and closes the through hole 115. The cap 13 includes an explosion-proof area 1331 and other areas 1332, and the thickness a of the explosion-proof area 1331 is less than the thickness b of the other areas 1332

[0042] Wherein, a rectangular coordinate system is established with the length, width and height of the top cover assembly 10 as the three axes. In the embodiment of the present application, the first direction X is the length direction of the top cover assembly 10, the second direction Y is the width direction of the top cover assembly 10, and the third direction Z is the height direction of the top cover assembly 10.

[0043] Specifically, the first surface 111 of the top cover 11 is the upper surface of the top cover 11, and the second surface 113 of the top cover 11 is the lower surface of the top cover 11. The material of the top cover 11 is a conductive material, including but not limited to aluminum, iron, copper, aluminum alloy, or iron alloy, etc. The shape of the projection surface of the top cover 11 in the XY plane can be circular, oval, triangular, quadrilateral, or other polygons, etc., which is not limited herein. In this embodiment, the shape of the projection surface of the top cover 11 is rectangular.

[0044] The shape of the projection surface of the through hole 115 in the XY plane can be circular, oval, triangular, quadrilateral, or other polygons, etc., which is not limited herein. In this embodiment, the through hole 115 is rectangular. The number of through holes 115 can be one or multiple. In this application, the through hole 115 is one. The through hole 115 can be used for gas venting when the internal pressure of the battery 100 is too high.

[0045] The cap 13 is disposed opposite to the top cover 11 in the third direction Z. The cap 13 protrudes relative to the first surface 111 of the top cover 11 to form an accommodation cavity 131 with the top cover 11. The cap 13 can be integrally formed with the top cover 11 or separately formed. The top 133 and the side 135 of the cap 13 can be integrally formed or separately formed. In a possible embodiment, the materials of the top 133 and the side 135 of the cap 13 can be the same. For example, both the top 133 and the side 135 are made of aluminum material. In another embodiment, the materials of the top 133 and the side 135 can be different. For example, the top 133 is made of aluminum material and the side 135 is made of iron material. In the case where the top 133 and the side 135 are separately formed: In one example, a detachable connection method can be adopted between the side 135 and the top cover 11 to combine them together. The detachable connection methods include but are not limited to snap connection or screw connection, etc. In another example, a non-detachable connection method can be adopted between the side 135 and the top cover 11 to combine them together. The non-detachable connection methods include but are not limited to bonding or welding, etc. The top 133 is away from and covers at least part of the through hole 115. It can be that in the XY projection plane, the projection surface of the top 133 completely coincides with the projection surface of the through hole 115, or the projection surface of the top 133 completely contains the projection surface of the through hole 115, or the projection surface of the top 133 is completely contained by the projection surface of the through hole 115.

[0046] The thickness a of the explosion-proof area 1331 is less than the thickness b of the side 135. The explosion-proof area 1331 can be the entire area of the top 133 or a partial area of the top. In this application, the case where the explosion-proof area 1331 is the entire area of the top 133 is taken as an example for illustration. Therefore, the thickness a of the explosion-proof area 1331 here is the thickness of the top 133, and the other area 1332 here is the side 135, and the thickness b of the other area 1332 is the thickness of the side 135.

[0047] Specifically, the top portion 133 includes an inner surface 1333 and an outer surface 1335 that are opposite to each other in the thickness direction (third direction Z), the inner surface 1333 is located in the accommodating cavity 131, and the outer surface 1335 is located outside the accommodating cavity 131. The thickness a of the top portion 133 is the distance from the inner surface 1333 to the outer surface 1335. Similarly, the side portion 135 includes an inner side surface 1353 and an outer side surface 1355 that are opposite to each other, the inner side surface 1353 is located in the accommodating cavity 131, and the outer side surface 1355 is located outside the accommodating cavity 131. The thickness b of the side portion 135 is the distance from the inner side surface 1353 to the outer side surface 1355.

[0048] The thickness a of the top 133 is smaller than the thickness b of the side 135. When the material of the top 133 is the same as that of the side 135, the top 133 is weaker than the side 135 and has a lower opening pressure, that is, the top 133 is easier to open. Therefore, after the accommodating chamber 131 guides the gas to converge to the top 133, it can ensure that the top 133 reaches the opening pressure before the side 135, so that the gas is discharged from the top 133 in a directional manner, avoiding the gas and other substances such as fluids and sparks carried by the gas from splashing too widely after breaking through the explosion-proof area 1331, thereby contaminating other components.

[0049] When the explosion-proof zone 1331 is subjected to a pressure greater than or equal to 0.15Mpa, the explosion-proof zone 1331 opens and connects the accommodating chamber 131 with the outside world. That is, since the interior of the battery 100 is a closed cavity, when a large amount of gas and heat are abnormally generated inside the battery 100, the explosion-proof zone 1331 swells inside the battery 100 to a pressure greater than or equal to 0.15Mpa, and can be broken open by the gas to connect the accommodating chamber 131 with the outside world, thereby releasing the gas. When the pressure is greater than or equal to 0.15Mpa, the side portion 135 may also be broken by the gas, or it may not be broken by the gas. If the explosion-proof zone 1331 is a partial area of ​​the top 133, when the pressure is greater than or equal to 0.15Mpa, the other areas 1332 of the top 133 except the explosion-proof zone 1331 may also be broken by the gas, or it may not be broken by the gas. The maximum pressure that the cap 13 can withstand is determined by the properties of the cap 13 itself, such as the material, thickness, shape or other properties of the cap 13. If the maximum pressures that different areas of the cap 13 (such as the explosion-proof zone 1331 and the side 135) can withstand are inconsistent, it may be that the materials of different areas are inconsistent, or the materials may be consistent but the thickness is inconsistent. It is understandable that when the materials are consistent, the maximum pressure that can be sustained in the area with thin thickness is smaller. In this application, the maximum pressure that the structure can withstand is referred to as the opening pressure. When the pressure is greater than or equal to the opening pressure, the structure will be broken by the gas. For example, the opening pressure of the explosion-proof zone 1331 is 0.15Mpa.

[0050] Although traditional batteries are equipped with explosion-proof valves, even if the inside of the battery has severely expanded due to a large amount of gas and the internal pressure of the battery is uneven, because the inside of the battery contains various structures and there is little remaining internal space, the gas is blocked by the internal structure of the battery, the gas flow path is blocked, and the gas cannot flow to the explosion-proof valve to break through the explosion-proof valve. In the top cover assembly 10 of the present application, the cap 13 and the top cover 11 enclose a receiving cavity 131. The receiving cavity 131 can be communicated with the inside of the battery 100 through the through hole 115, providing additional space inside the battery 100, storing some of the gas generated inside the battery 100, and preventing the battery 100 from rapidly bulging. The receiving cavity 131 can also serve as a gas flow path, guiding the gas to converge to the cap 13. The thickness of the explosion-proof area 1331 is smaller than that of other areas 1332. Therefore, the explosion-proof area 1331 is more easily opened. After reaching a certain pressure, the explosion-proof area 1331 is broken by the gas, so that the receiving cavity 131 is communicated with the outside world, realizing the directional exhaust of the gas from the receiving cavity 131 to the explosion-proof area 1331, and improving the safety of the battery 100 during use. At the same time, because the receiving cavity 131 can converge and concentrate the gas, the cap 13 can carry more gas while allowing the explosion-proof area 1331 to be broken through at a lower pressure, improving the sensitivity of the explosion-proof area 1331 and reducing the probability of the battery 100 exploding due to excessive bulging.

[0051] Please refer to Figure 1 and Figure 3 , in some embodiments, the explosion-proof area 1331 is the entire area of the top 133.

[0052] Specifically, since the explosion-proof area 1331 is the entire area of the top 133, when the pressure of the gas received by the top 133 is greater than 0.15 Mpa, the entire top 133 can be broken through and communicated with the outside world. The entire area of the top 133 can become an open area communicated with the outside world, with large space utilization rate and good exhaust effect, and can timely discharge the gas from the inside of the battery 100 to the outside of the battery 100 to achieve the purpose of pressure relief, thereby effectively avoiding the explosion of the battery 100 due to excessive bulging.

[0053] Please refer to Figure 1 and Figure 3 , in some embodiments, the explosion-proof area 1331 is a partial area of the top 133.

[0054] Specifically, the explosion-proof area 1331 can be located at any position on the top 133, at the center of the top 133, or at a position near the periphery of the top 133. The explosion-proof area 1331 can be set at a position away from some key structures according to the positions of the battery 100 and other structures of the top cover assembly 10, so as to prevent gas and other substances such as fluid and sparks carried by the gas from contaminating other structures after breaking through the explosion-proof area 1331. It can be understood that the opening pressure of the explosion-proof area 1331 is less than that of the other area 1332 of the top 133 except the explosion-proof area 1331. The explosion-proof area 1331 and the other area 1332 can be set with different opening pressures through different material designs, or with different opening pressures through different thickness designs under the same material.

[0055] Please refer to Figure 3 and Figure 4 , in some embodiments, the included angle α between the top 133 and the side 135 is an obtuse angle.

[0056] Specifically, the included angle between the top 133 and the side 135 is the included angle between the surface of the top 133 located in the accommodating cavity 131 and the surface of the side 135 located in the accommodating cavity 131. The included angle α between the top 133 and the side 135 can be 91°, 95°, 109°, 112°, 116°, 120°, 134°, 136°, 146° or 149°, etc.

[0057] The included angle between the top 133 and the side 135 is an obtuse angle, that is, the side 135 is inclined and close to the top 133, which can further guide the gas in the accommodating cavity 131 to converge below the top 133, and the concentration of the gas is also beneficial to the opening of the explosion-proof area 1331 of the top 133.

[0058] Please refer to Figure 2 , in some embodiments, the ratio S1 / S2 of the area S1 of the through hole 115 to the area S2 of the top cover 11 satisfies: 1 / 2 ≤ S1 / S2 ≤ 4 / 5.

[0059] Specifically, both the area S1 of the through hole 115 and the area S2 of the top cover 11 are areas in the XY projection plane. The ratio S1 / S2 of the area S1 of the through hole 115 to the area S2 of the top cover 11 can be 1 / 2, 13 / 25, 14 / 25, 3 / 5, 16 / 25, 33 / 50, 17 / 25, 18 / 25, 19 / 25, or 4 / 5, as well as any other value between 1 / 2 and 4 / 5. If the ratio S1 / S2 of the area S1 of the through hole 115 to the area S2 of the top cover 11 is less than 1 / 2, the area S1 of the through hole 115 is too small, that is, the flow-through area of the gas at the through hole 115 is too small, which is not conducive to the gas entering the accommodation cavity 131 and is also not conducive to the opening of the explosion-proof area 1331. If the ratio S1 / S2 of the area S1 of the through hole 115 to the area S2 of the top cover 11 is greater than 4 / 5, the area S1 of the through hole 115 is too large, occupying too much area of the top cover 11 and is not conducive to the arrangement of other components of the top cover 11.

[0060] The ratio S1 / S2 of the area S1 of the through hole 115 to the area S2 of the top cover 11 satisfies: 1 / 2 ≤ S1 / S2 ≤ 4 / 5, which can provide a sufficient flow-through area for the gas, improve the rate of gas passing through per unit time, be conducive to the gas entering the accommodation cavity 131, and is also conducive to the opening of the explosion-proof area 1331. At the same time, it also reserves sufficient space for the arrangement of other components of the top cover 11. In addition, it should be noted that when the projected area of the top 133 in the XY plane is greater than the projected area of the through hole 115 in the XY plane, the ratio S3 / S2 of the area S3 of the top 133 to the area S2 of the top cover 11 also satisfies: 1 / 2 ≤ S3 / S2 ≤ 4 / 5.

[0061] Please refer to Figure 2 , in some embodiments, the first surface 111 is provided with a positioning groove 1111. The positioning groove 1111 surrounds the through hole 115. One end of the side portion 135 far from the top 133 protrudes and extends towards the outside of the central axis of the cap 13 with a flange 137, and the flange 137 is installed in the positioning groove 1111.

[0062] Specifically, the positioning groove 1111 can quickly position the cap 13 when installing the cap 13 and ensure that the upper surface of the flange 137 of the cap 13 is aligned with the first surface 111. The flange 137 protrudes and extends from the side portion 135 and is installed in the positioning groove 1111, which can increase the contact area between the cap 13 and the top cover 11 and improve the installation strength between the cap 13 and the top cover 11. In addition, the setting of the flange 137 can prevent the cap 13 from rotating after installation and ensure that the cap 13 remains in the correct position.

[0063] Please refer to Figure 2 and Figure 5 , in some embodiments, the thickness b of the side portion 135 satisfies: 0.2 mm ≤ b ≤ 4.0 mm.

[0064] Specifically, the thickness b of the side portion 135 can be 0.4 mm, 1.4 mm, 1.7 mm, 2.4 mm, 2.6 mm, 3.4 mm, 3.7 mm, 4.4 mm, 4.7 mm, 5.0 mm or any other value between 0.4 mm and 5.0 mm. When the thickness b of the side portion 135 is less than 0.4 mm, the thickness b of the side portion 135 is too small, and the supporting effect of the side portion 135 on the top portion 133 is limited. The side portion 135 is prone to deformation when subjected to an external force, resulting in the top portion 133 deviating from its original position, and also causing the cap 13 to deform and the volume of the accommodation cavity 131 to become smaller. When the thickness b of the side portion 135 is greater than 5.0 mm, the thickness b of the side portion 135 is too large. With the size of the through hole 115 being fixed, the side portion 135 will occupy the installation space of the through hole 115 or other components on the first surface 111.

[0065] When the thickness b of the side portion 135 satisfies 0.2 mm ≤ b ≤ 4.0 mm, the side portion 135 can stably support the top portion 133, and the side portion 135 is not easily deformed when subjected to an external force, thereby maintaining the shape of the cap 13. At the same time, the side portion 135 will not occupy the installation space of the through hole 115 or other components on the first surface 111, making the layout of the top cover assembly 10 more reasonable.

[0066] Please refer to Figure 2 and Figure 5 , in some embodiments, the height H of the cap 13 satisfies 2 mm ≤ H ≤ 50 mm.

[0067] Specifically, the height of the cap 13 is the distance between the inner surface 1333 and the first surface 111 in the third direction Z. The height H of the cap 13 can be 2 mm, 3 mm, 9 mm, 13 mm, 23 mm, 27 mm, 32 mm, 38 mm, 45 mm, 50 mm or any other value between 2 mm and 50 mm. If the height H of the cap 13 is less than 2 mm, with the size of the through hole 115 being fixed, the too low height will also result in too small a volume of the accommodation cavity 131, and the storage effect on the gas is limited. If the height H of the cap 13 is greater than 50 mm, then the cap 13 occupies too much space, which is not conducive to the arrangement of multiple batteries 100.

[0068] When the height H of the cap 13 satisfies 2 mm ≤ H ≤ 50 mm, it can ensure that the height of the accommodation cavity 131 is appropriate. Within a reasonable space range, it can accommodate enough gas, and can also serve as a gas flow path to guide the gas to converge below the top portion 133, and will not occupy space, ensuring that multiple batteries 100 can be arranged reasonably.

[0069] Please refer to Figure 2 and Figure 5, in some embodiments, the explosion-proof area 1331 is provided with a scoring groove 13311, and the value range of the thickness c of the top 133 at the scoring groove 13311 is [0.2 mm, 0.7 mm].

[0070] Specifically, the scoring groove 13311 is a groove structure provided on the explosion-proof area 1331 for positioning the opening position of the explosion-proof area 1331. The thickness c of the top 133 at the scoring groove 13311 is less than the thickness of other positions of the top 133, which can make the scoring groove 13311 easier to be torn and thus open the explosion-proof area 1331. The shape of the projection surface of the explosion-proof area 1331 on the XY plane can be circular, elliptical, triangular, quadrilateral or other polygons, etc., which is not limited here. The number of the scoring grooves 13311 can be one or more. The scoring groove 13311 can be provided on the inner surface 1333 of the explosion-proof area 1331 or on the outer surface 1335 of the explosion-proof area 1331. The thickness c of the top 133 at the scoring groove 13311 is the remaining thickness of the top 133 after removing the depth of the scoring groove 13311 in the thickness direction of the top 133. That is, the sum of the depth of the scoring groove 13311 and the thickness c of the top 133 at the scoring groove 13311 is the thickness of the top 133. The thickness c of the top 133 at the scoring groove 13311 can be 0.2 mm, 0.24 mm, 0.27 mm, 0.34 mm, 0.36 mm, 0.38 mm, 0.44 mm, 0.45 mm, 0.6 mm, 0.7 mm or any other value between 0.2 mm and 0.7 mm. If the thickness c of the top 133 at the scoring groove 13311 is less than 0.2 mm, the thickness c of the top 133 at the scoring groove 13311 is too thin and the scoring groove 13311 is likely to be accidentally touched and opened. If the thickness c of the top 133 at the scoring groove 13311 is greater than 0.7 mm, the scoring groove 13311 is not easy to open and the opening position of the explosion-proof area 1331 cannot be positioned.

[0071] The value range of the thickness c of the top 133 at the scoring groove 13311 is [0.2 mm, 0.7 mm], which can prevent the scoring groove 13311 from being accidentally touched and opened, and ensure the sensitivity at the scoring groove 13311 so that the scoring groove 13311 can be opened when the opening pressure is reached.

[0072] Please refer to Figure 4 , in some embodiments, the scoring groove 13311 is provided on the inner surface 1333 and / or the outer surface 1335.

[0073] Specifically, the scoring groove 13311 is provided on the inner surface 1333, which can prevent the area of the top 133 provided with the scoring groove 13311 from being knocked and opened during transportation. The scoring groove 13311 provided on the outer surface 1335 is easier to process.

[0074] Please refer to Figure 2 , in some embodiments, the cross-section of the cap 13 intercepted by a plane parallel to the first surface 111 is circular, elliptical or polygonal.

[0075] Specifically, the polygon includes a triangle, a rectangle, a pentagon, a hexagon or a polygon with other numbers of sides. The cross-section of the cap 13 intercepted by a plane parallel to the first surface 111 being circular, elliptical or polygonal enables the cap 13 to be applicable to the top cover assemblies 10 of different shapes.

[0076] Please refer to Figure 2 , in some embodiments, the cap 13 is a metal cap.

[0077] Specifically, the cap 13 can be made of a metal material, which is convenient for connecting with the top cover (such as welding). At the same time, the metal material has a long service life, which can extend the service life of the cap 13.

[0078] Please refer to Figure 2 , in some embodiments, the top cover assembly 10 further includes a terminal post 15 and a connecting piece 16. The terminal post 15 penetrates through the top cover 11. The connecting piece 16 is disposed on the side where the second surface 113 of the top cover 11 is located and is electrically connected to the terminal post 15. At least a part of the structure of the connecting piece 16 passes through the through hole 115 and extends into the accommodating cavity 131. The tab 51 on the battery cell 50 is electrically connected to the connecting piece 16 of the top cover assembly 10.

[0079] Specifically, the connecting piece 16 mainly has two functions. First, the connecting piece 16 is used to electrically connect the terminal post 15 and the tab 51 on the battery cell 50. Second, the connecting piece 16 is used to pull the tab 51 into the accommodating cavity 131 so that the tab 51 can be accommodated in the accommodating cavity 131 in a flat posture, avoiding the tab 51 from being bent or stacked inside the battery 100. More specifically, after the connecting piece 16 is connected to the tab 51, a part of the connecting piece 16 passes through the through hole 115 and extends into the accommodating cavity 131, and another part of the connecting piece 16 is electrically connected to the terminal post 15. The connecting piece 16 pulling the tab 51 into the accommodating cavity 131 can make full use of the space, improve the energy density of the battery 100, and also avoid the tab 51 from being bent, thus avoiding the short-circuit risk caused by the contact between the tab 51 and the battery cell 50 due to the bending of the tab 51. The connecting piece 16 is made of a conductive material, which can be the same as the material forming the tab 51 or different from the material forming the tab 51.

[0080] Please refer to Figure 1 and Figure 2, in some embodiments, the battery 100 further includes a housing 30 and an electrode assembly 50. The housing 30 is provided with an opening, and the top cover assembly 10 is installed on the housing 30 to close the opening. The electrode assembly 50 is accommodated in the housing 30, and the tab 51 on the electrode assembly 50 is electrically connected to the adapter plate 16 of the top cover assembly 10.

[0081] The housing 30 is a structure for placing the electrode assembly 50. The cross-section of the housing 30 (the plane intercepted by the XY plane) can be, but is not limited to, circular, elliptical, square or other polygons. The material of the housing 30 includes, but is not limited to, metal or non-metal, where metals include aluminum, iron, steel, aluminum alloy or ferroalloy, etc., and non-metals include, but are not limited to, plastics, etc. In this application, the cross-section of the housing 30 is square, so that it can be conveniently integrated into the battery 100. The material of the housing 30 is aluminum alloy, so that the battery 100 can be made lighter and more convenient for transportation while ensuring the stiffness.

[0082] The electrode assembly 50 is the core structure in the battery 100 that realizes the conversion between electrical energy and chemical energy through chemical reactions for charging and discharging. The electrode assembly 50 is generally made by winding a pole piece assembly around a mandrel. The pole piece assembly mainly includes a negative electrode sheet, a positive electrode sheet and a separator. In a possible design, the negative electrode sheet, the separator and the positive electrode sheet are stacked in sequence and adhered to the mandrel by means of glue or hot melting, etc., and then wound to form the electrode assembly 50. After the electrode assembly 50 is formed, there are gaps, and the electrolyte can enter the electrode assembly 50 through the gaps. The electrolyte is used to soak the electrode assembly 50 to ensure that ions can move freely during the charging and discharging process of the electrode assembly 50. The electrolyte includes, but is not limited to, electrolyte lithium salts, organic solvents and additives, etc. The negative electrode sheet includes a negative electrode current collector (such as copper foil) and a negative electrode active material layer (such as carbon or silicon) coated on the surface of the negative electrode current collector. The positive electrode sheet includes a positive electrode current collector (such as aluminum foil) and a positive electrode active material layer (such as ternary material, lithium iron phosphate or lithium cobaltate) coated on the surface of the positive electrode current collector. The separator is located between the adjacent negative electrode sheet and positive electrode sheet to separate the negative electrode sheet and the positive electrode sheet.

[0083] Please refer to Figure 4 , in some embodiments, the thickness M of the housing 30 satisfies: M ≤ 4 mm.

[0084] Specifically, the thickness M of the housing 30 can be 1 mm, 1.3 mm, 1.9 mm, 2.3 mm, 2.4 mm, 2.7 mm, 3.2 mm, 3.8 mm, 3.9 mm, 4 mm or any other value between 1 mm and 4 mm. If the thickness of the housing 30 is greater than 4 mm, the thickness of the housing 30 is too large, the mass of the battery 100 increases, and it is not conducive to the heat dissipation inside the battery 100. When the thickness of the housing 30 is less than or equal to 4 mm, the mass of the battery 100 can be controlled, and it is also conducive to the heat dissipation inside the battery 100.

[0085] Please refer toFigure 4 and Figure 5 , in some embodiments, the thickness a of the top 133 and the thickness M of the housing 30 satisfy: a ≤ M.

[0086] Specifically, if the thickness a of the top 133 is greater than the thickness M of the housing 30, then, when the materials are the same, the opening pressure of the housing 30 is less than the opening pressure of the top 133. When a certain pressure is reached inside the battery 100, the housing 30 will be broken by the gas prior to the top 133, causing the electrolyte inside the housing 30 to flow out, leading to safety problems. When the thickness a of the top 133 is less than or equal to the thickness M of the housing 30, when a certain pressure is reached inside the battery 100, the top 133 will be broken by the gas prior to the housing 30, avoiding the outflow of the electrolyte inside the housing 30.

[0087] Please refer to Figure 1 and Figure 6 , the present application provides an energy storage device 1000. The energy storage device 1000 includes the battery 100 described in any one of the above embodiments.

[0088] Specifically, the energy storage device 1000 of the present application refers to a device that can convert the chemical energy stored therein into electrical energy, that is, a device that converts the pre-stored energy into externally available electrical energy. The energy storage device 1000 can be charged and store electrical energy, and can also discharge to supply power to other external devices. It can be understood that the energy storage device 1000 may include, but is not limited to, a battery pack, a battery module, or a battery system, etc.

[0089] In some embodiments of the present application, the energy storage device 1000 includes a plurality of batteries 100 and a box body 300. The box body 300 is used to provide an accommodation space for the batteries 100, and the box body 300 can adopt various structures. In some embodiments, the box body 300 may include a box cover 301 and a box body 303. The box cover 301 and the box body 303 are covered with each other, and the box cover 301 and the box body 303 jointly define an accommodation space for accommodating the batteries 100. The box body 303 can be a hollow structure with one end open, and the box cover 301 can be a plate-like structure. The box cover 301 is covered on the opening side of the box body 303 so that the box cover 301 and the box body 303 jointly define the accommodation space; the box cover 301 and the box body 303 can also both be hollow structures with one side open, and the opening side of the box cover 301 is covered on the opening side of the box body 303. Of course, the box body 300 formed by the box cover 301 and the box body 303 can be of various shapes, for example, a cylinder or a cuboid, etc. The energy storage device 1000 may further include other structures. For example, the energy storage device 1000 may further include a busbar component for realizing electrical connection between the plurality of batteries 100.

[0090] In the top cover assembly 10 of the battery 100 of the energy storage device 1000, the cap 13 and the top cover 11 enclose a receiving cavity 131. The receiving cavity 131 can communicate with the inside of the battery 100 through the through hole 115, providing additional space inside the battery 100, storing some of the gas generated inside the battery 100, and preventing the battery 100 from bulging rapidly. The receiving cavity 131 can also serve as a gas flow path, guiding the gas to converge to the cap 13. The thickness of the explosion-proof area 1331 is less than that of other areas 1332, so the explosion-proof area 1331 is more easily opened. After reaching a certain pressure, the explosion-proof area 1331 is ruptured by the gas, so that the receiving cavity 131 communicates with the outside world, realizing the directional exhaust of the gas from the receiving cavity 131 to the explosion-proof area 1331, and improving the safety of using the battery 100. At the same time, since the receiving cavity 131 can converge and concentrate the gas, the cap 13 can carry more gas while allowing the explosion-proof area 1331 to be broken through at a lower pressure, improving the sensitivity of the explosion-proof area 1331 and reducing the probability of the battery 100 exploding due to excessive bulging.

[0091] Please refer to Figure 1 and Figure 7 , the present application provides an electrical device 10000. The electrical device 10000 includes the energy storage device 1000 of any one of the above embodiments.

[0092] Specifically, the battery 100 or the energy storage device 1000 disclosed in the present application can be used in an electrical device 10000 that uses the energy storage device 1000 as a power source. The electrical device 10000 can be, but is not limited to, an electric vehicle, a power tool, a mobile phone, a ship, a spacecraft, etc. Among them, the spacecraft can include an unmanned aerial vehicle, a rocket, a space shuttle, etc. The present application only takes the electrical device 10000 as a vehicle as an example for illustration. The vehicle can be a fuel vehicle, a gas vehicle or a new energy vehicle. The new energy vehicle can be a pure electric vehicle, a hybrid vehicle or an extended-range vehicle, etc. The energy storage device 1000 is arranged inside the vehicle. The energy storage device 1000 can be arranged at the bottom, head or tail of the vehicle. The energy storage device 1000 can be used for power supply of the vehicle. For example, the energy storage device 1000 can be used as the operating power source of the vehicle. The vehicle can also include a controller and a motor. The controller is used to control the battery 100 pack to supply power to the motor. For example, it is used for the working power requirements during the start, navigation and driving of the vehicle. In some embodiments, the energy storage device 1000 can not only be used as the operating power source of the vehicle, but also be used as the driving power source of the vehicle, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle.

[0093] In the top cover assembly 10 of the energy storage device 1000 of the electrical equipment 10000, the cap 13 and the top cover 11 enclose a containing cavity 131. The containing cavity 131 can be internally communicated with the inside of the battery 100 through the through hole 115, providing additional space inside the battery 100, storing part of the gas generated inside the battery 100, and preventing the battery 100 from bulging rapidly. The containing cavity 131 can also be used as a gas flow path to guide the gas to converge to the cap 13. The thickness of the explosion-proof area 1331 is smaller than that of other areas 1332. Therefore, the explosion-proof area 1331 is more easily opened. After reaching a certain pressure, the explosion-proof area 1331 is ruptured by the gas, so that the containing cavity 131 is communicated with the outside world, realizing the directional exhaust of the gas from the containing cavity 131 to the explosion-proof area 1331 and improving the use safety of the battery 100. At the same time, since the containing cavity 131 can converge and concentrate the gas, the cap 13 can carry more gas while allowing the explosion-proof area 1331 to be broken through at a lower pressure, improving the sensitivity of the explosion-proof area 1331 and reducing the probability of the battery 100 exploding due to excessive bulging.

[0094] Although the embodiments of the present application have been shown and described, those of ordinary skill in the art can understand that various changes, modifications, substitutions, and variations can be made to the embodiments of the present application without departing from the principle and spirit of the present application. The scope of the present application is defined by the claims and their equivalents.

Claims

1. A top cover assembly (10), characterized in that: include: A top cover (11), the top cover (11) comprising a first surface (111) and a second surface (113) opposite to each other, the top cover (11) being provided with a through hole (115) penetrating the first surface (111) and the second surface (113); and A cover cap (13), wherein the cover cap (13) is arranged on a side where the first surface (111) of the top cover (11) is located, the cover cap (13) protrudes from the first surface (111) and forms a receiving cavity (131) with the top cover (11), the cover cap (13) covers and closes the through hole (115), the cover cap (13) comprises an explosion-proof zone (1331) and other zones (1332), and the thickness a of the explosion-proof zone (1331) is less than the thickness b of the other zones (1332).

2. The top cover assembly (10) according to claim 1, characterized in that: The cover cap (13) comprises a top portion (133) and a side portion (135), wherein the side portion (135) extends from the periphery of the top portion (133) and is connected to the top cover (11), the side portion (135) surrounds the through hole (115), the top portion (133) is away from and covers the through hole (115), and the explosion-proof zone (1331) is arranged at the top portion (133).

3. The top cover assembly (10) according to claim 2, characterized in that: The side portion (135) is located between the top portion (133) and the top cover (11), and the included angle between the top portion (133) and the side portion (135) is an obtuse angle.

4. The top cover assembly (10) according to claim 1, characterized in that: The ratio S1 / S2 of the area S1 of the through hole (115) to the area S2 of the top cover (11) satisfies: 1 / 2≤S1 / S2≤4 / 5.

5. The top cover assembly (10) according to claim 2, characterized in that: The first surface (111) is provided with a positioning groove (1111), and the positioning groove (1111) surrounds the through hole (115); an end of the side portion (135) away from the top (133) is provided with a convex edge (137), and the convex edge (137) is installed in the positioning groove (1111).

6. The top cover assembly (10) according to claim 1, characterized in that: When the explosion-proof zone (1331) is subjected to a pressure greater than or equal to 0.15 Mpa, the explosion-proof zone (1331) opens and connects the accommodating cavity (131) with the outside world.

7. The top cover assembly (10) according to claim 2, characterized in that: The thickness b of the side portion (135) satisfies: 0.2 mm ≤ b ≤ 4.0 mm.

8. The top cover assembly (10) according to claim 1, characterized in that: The height H of the cap (13) satisfies: 2mm≤H≤50mm.

9. The top cover assembly (10) according to claim 1, characterized in that: A cross section of the cap (13) cut by a plane parallel to the first surface (111) is circular, elliptical or polygonal; and / or the cap (13) is a metal cap (13).

10. The top cover assembly (10) according to claim 1, characterized in that: The explosion-proof zone (1331) is provided with a notch groove (13311). The thickness c of the explosion-proof zone (1331) at the notch groove (13311) has a value range of [0.2 mm, 0.7 mm].

11. The top cover assembly (10) according to claim 1, characterized in that: The top cover assembly (10) further comprises: A pole (15), the pole (15) being passed through the top cover (11); and An adapter plate (16), the adapter plate (16) being arranged on a side where the second surface (113) of the top cover (11) is located and being electrically connected to the pole (15), and at least a portion of the structure of the adapter plate (16) passing through the through hole (115) and extending into the accommodating cavity (131).

12. A battery (100), characterized in that: include: The top cover assembly (10) according to any one of claims 1 to 11; A shell (30), wherein the shell (30) is provided with an opening, and the top cover assembly (10) is installed on the shell (30) and closes the opening; and A battery cell (50), the battery cell (50) being accommodated in the housing (30), and a pole ear (51) of the battery cell (50) being electrically connected to a switching piece (16) of the top cover assembly (10).

13. The battery (100) according to claim 12, characterized in that: The thickness a of the top (133) of the cap (13) and the thickness M of the shell (30) satisfy: a≤M; and / or, The thickness M of the shell (30) satisfies: M≤4 mm.

14. An energy storage device (1000), characterized in that: A battery (100) comprising any one of claims 12 to 13.

15. An electrical device (10000), characterized in that: Comprising the energy storage device (1000) as claimed in claim 14.

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