Single battery and battery pack

Abstract

The embodiment of the utility model provides a single battery and a battery pack. The single battery comprises a battery cell, a shell, an anti-explosion valve and a filtering structure, the battery cell is arranged in the shell; the shell is provided with a mounting hole, and the anti-explosion valve is arranged in the mounting hole; the filtering structure is arranged outside the shell and at least covers the anti-explosion valve, the filtering structure comprises at least two layers of filter screens, and the filter screens are used for intercepting particulate matter in the flue gas. By arranging the filtering structure, particulate matters discharged during pressure relief of the anti-explosion valve can be effectively intercepted, so that the particulate matters are prevented from being splashed to other single batteries without thermal runaway to cause thermal runaway, and the use safety of the single batteries is favorably improved.

Description

Technical Field

[0001] The present application belongs to the field of battery technology, and specifically relates to a single cell and a battery pack. Background Art

[0002] The battery pack is a key component of new energy vehicles. The battery pack includes multiple single cells, among which single cells may experience thermal runaway under mechanical, electrical or thermal abuse. Single cells are usually equipped with explosion-proof valves. When thermal runaway occurs in a single cell and the pressure inside the single cell exceeds the preset pressure of the explosion-proof valve, the explosion-proof valve can release the pressure to prevent the single cell from exploding.

[0003] However, when the explosion-proof valve releases pressure, a large amount of high-temperature flue gas will be ejected, which includes gas and particulate matter, among which the particulate matter includes positive electrode material particles, impact-crushed copper and aluminum current collectors, etc. When the high-temperature flue gas is ejected, these particles may splash onto other single cells that have not experienced thermal runaway, causing an arc effect, resulting in a local micro-short circuit and thus triggering thermal runaway. Utility Model Content

[0004] The present application aims to provide a single cell and a battery pack to solve the problem that when the existing explosion-proof valve releases pressure, the discharged particles may splash onto other single cells that have not experienced thermal runaway and cause thermal runaway.

[0005] In order to solve the above technical problems, this application is implemented as follows:

[0006] In a first aspect, the present application discloses a single cell battery, the single cell battery comprising: a battery cell, a shell, an explosion-proof valve and a filter structure;

[0007] The battery core is arranged in the housing;

[0008] The housing is provided with a mounting hole, and the explosion-proof valve is arranged in the mounting hole;

[0009] The filter structure is arranged outside the shell and at least covers the explosion-proof valve. The filter structure includes at least two layers of filter screens, and the filter screens are used to intercept particulate matter in the smoke.

[0010] Optionally, the filter screen is provided with 2-6 layers.

[0011] Optionally, in the two adjacent layers of filter screens, the one disposed close to the explosion-proof valve is the first filter screen, and the one disposed away from the explosion-proof valve is the second filter screen;

[0012] The first filter screen is provided with a first mesh, and the first mesh has a first center line;

[0013] The second filter screen is provided with a second mesh, the second mesh has a second center line, and the second center line coincides with the first center line.

[0014] Optionally, in the two adjacent layers of filter screens, the one disposed close to the explosion-proof valve is the first filter screen, and the one disposed away from the explosion-proof valve is the second filter screen;

[0015] The first filter screen is provided with a first mesh, and the first mesh has a first center line;

[0016] The second filter screen is provided with a second mesh, the second mesh has a second center line, and the second center line is parallel to and does not overlap with the first center line.

[0017] Optionally, in the two adjacent layers of filter screens, the one disposed close to the explosion-proof valve is the first filter screen, and the one disposed away from the explosion-proof valve is the second filter screen;

[0018] The first filter screen is provided with a first mesh;

[0019] The second filter screen is provided with second mesh openings, and the second mesh openings are the same as the first mesh openings.

[0020] Optionally, in the two adjacent layers of filter screens, the one disposed close to the explosion-proof valve is the first filter screen, and the one disposed away from the explosion-proof valve is the second filter screen;

[0021] The first filter screen is provided with a first mesh, and the first mesh has a first size;

[0022] The second filter screen is provided with second meshes, the second meshes have a second size, and the second size is smaller than the first size.

[0023] Optionally, the filter screen is provided with mesh holes, the mesh holes are circular mesh holes, the diameter of the circular mesh holes is d, and satisfies: 0.1mm≤d≤1.5mm.

[0024] Optionally, the filtering structure further comprises a mounting member;

[0025] The mounting member is connected to the housing and is disposed around the circumference of the explosion-proof valve;

[0026] The filter screen is connected to the mounting member.

[0027] Optionally, the mounting member comprises a flange portion and a cylindrical portion which are sequentially arranged along the emission direction of the smoke;

[0028] The flange portion is connected to the shell;

[0029] The cylindrical portion has an inner wall, and the filter is connected to the inner wall.

[0030] Optionally, the height of the filter structure along the emission direction of smoke is h, satisfying 8≤h≤12mm.

[0031] Optionally, the spacing between two adjacent layers of filter screens along the flue gas emission direction is n, satisfying 2≤n≤3mm.

[0032] In a second aspect, the present application further discloses a battery pack, which includes: a single cell battery as described in any one of the above items.

[0033] In the embodiment of the present application, the single cell includes: a battery cell, a shell, an explosion-proof valve and a filter structure; the battery cell is arranged in the shell; the shell is provided with a mounting hole, and the explosion-proof valve is arranged in the mounting hole; the filter structure is arranged outside the shell and at least covers the explosion-proof valve, and the filter structure includes at least two layers of filter screens, and the filter screen is used to intercept particulate matter in the flue gas. Since the filter structure is provided, and the filter structure includes at least two layers of filter screens. In this way, on the one hand, when the battery cell has thermal runaway and generates a large amount of high-temperature flue gas, the explosion-proof valve opens to release pressure, wherein the gas in the high-temperature flue gas can be discharged from the filter screen, thereby achieving pressure relief; the temperature and kinetic energy of the particulate matter in the high-temperature flue gas are reduced during the collision with the filter screen, so that the particulate matter is effectively intercepted, and the particulate matter is effectively prevented from splashing onto other single cells that have not experienced thermal runaway and causing thermal runaway, which is beneficial to improving the safety of the use of the single cell. On the other hand, since the filter screen is provided with at least two layers, the temperature and kinetic energy of the particulate matter in the high-temperature flue gas can be further reduced, thereby improving the interception effect of the particulate matter and further improving the safety of the use of the single cell. In addition, when the explosion-proof valve is separated from the mounting hole, the filtering structure can limit the explosion-proof valve, thereby effectively avoiding the problem of mechanical damage to other single cells caused by the explosion-proof valve being separated from the mounting hole.

[0034] Additional aspects and advantages of the present invention will be given in part in the following description, and in part will become apparent from the following description, or will be learned through the practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0036] Figure 1 It is a schematic diagram of the structure of a single cell in the prior art;

[0037] Figure 2 is a schematic diagram of the structure of a single cell provided in an embodiment of the present application;

[0038] Figure 3 is a structural schematic diagram of a filtering structure provided in an embodiment of the present application;

[0039] Figure 4 It is a structural schematic diagram of a filtering structure provided in an embodiment of the present application;

[0040] Figure 5 It is a structural schematic diagram of another filtering structure provided in an embodiment of the present application.

[0041] Figure numerals: 1. explosion-proof valve, 2. filtering structure, 21. filter screen, 211. first filter screen, 212. second filter screen, 22. mesh, 221. first mesh, 222. second mesh, 23. mounting part, 231. flange part, 232. cylindrical part, 3. shell, 31. box body, 32. cover plate, 321. mounting hole, X. first direction. DETAILED DESCRIPTION

[0042] The embodiments of the utility model will be described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the utility model, and cannot be understood as limiting the utility model. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0043] The term "first" or "second" in the specification and claims of this application may include one or more of the features explicitly or implicitly. In the description of this utility model, unless otherwise specified, "multiple" means two or more. In addition, "and / or" in the specification and claims means at least one of the connected objects, and the character " / " generally means that the objects connected before and after are in an "or" relationship.

[0044] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0045] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0046] Reference Figure 1 , shows a schematic diagram of the structure of a single cell in the prior art, such as Figure 1 As shown, in the prior art, a single cell includes a battery cell, a shell 3 and an explosion-proof valve 1, wherein the battery cell is arranged in the shell 3, the shell 3 is provided with a mounting hole 321, and the explosion-proof valve 1 is arranged in the mounting hole 321. In the case where the battery cell has thermal runaway and generates a large amount of high-temperature flue gas, when the pressure in the shell 3 exceeds the preset pressure of the explosion-proof valve 1, the explosion-proof valve 1 opens to allow a large amount of high-temperature flue gas to be ejected. In this process, since the high-temperature flue gas includes gas and particulate matter, wherein the particulate matter includes positive electrode material particles, impact-crushed copper, aluminum current collectors and other substances. Therefore, when the particulate matter splashes onto other single cells that have not experienced thermal runaway, an arc effect will be generated, resulting in a local micro-short circuit and thus causing thermal runaway.

[0047] An embodiment of the present application provides a single cell battery, and the single cell battery of the present application is described in detail below with reference to the accompanying drawings.

[0048] Reference Figure 2 , showing a schematic diagram of the structure of a single cell provided in an embodiment of the present application, referring to Figure 3 , showing a schematic diagram of the structure of the filtering structure provided in the embodiment of the present application, referring to Figures 4 to 5 , respectively showing the structural schematic diagrams of two filtering structures provided in the embodiments of the present application.

[0049] like Figure 2 As shown, the present application provides a single cell battery, which includes: a battery cell, a shell 3, an explosion-proof valve 1 and a filter structure 2; the battery cell is arranged in the shell 3; the shell 3 is provided with a mounting hole 321, and the explosion-proof valve 1 is arranged in the mounting hole 321; the filter structure 2 is arranged outside the shell 3 and at least covers the explosion-proof valve 1, and the filter structure 2 includes at least two layers of filter screens 21, and the filter screens 21 are used to intercept particulate matter in the flue gas.

[0050] In the embodiment of the present application, since a filter structure 2 is provided, the filter structure 2 is provided outside the housing 3 and at least covers the explosion-proof valve 1, wherein the filter structure 2 includes at least two layers of filter screens 21. Thus, on the one hand, when the battery cell undergoes thermal runaway and generates a large amount of high-temperature flue gas, the explosion-proof valve 1 is opened for pressure relief, wherein the gas in the high-temperature flue gas can be discharged from the filter screen 21, thereby achieving pressure relief; the temperature and kinetic energy of the particles in the high-temperature flue gas are reduced during the collision with the filter screen 21, thereby effectively intercepting the particles, effectively preventing the particles from splashing onto other single cells that have not undergone thermal runaway and causing thermal runaway, which is beneficial to improving the safety of the single cells. On the other hand, since the filter screen 21 is provided with at least two layers, the temperature and kinetic energy of the particles in the high-temperature flue gas can be further reduced, thereby improving the interception effect of the particles and further improving the safety of the single cells. In addition, when the explosion-proof valve 1 is separated from the mounting hole 321, the filter structure 2 can limit the explosion-proof valve 1, thereby effectively avoiding the problem of mechanical damage to other single cells after the explosion-proof valve 1 is separated from the mounting hole 321.

[0051] It should be noted that when the explosion-proof valve 1 is relieving pressure, the high-temperature flue gas is usually ejected radially. For ease of understanding, the embodiment of the present application assumes that the emission direction of the flue gas is a certain direction, that is, the first direction X shown in the figure. In addition, under normal circumstances, the temperature of the high-temperature flue gas discharged by the explosion-proof valve 1 is about 600°C. Therefore, in order to prevent the filter structure 2 from melting at high temperature, the melting point of the material used in the filter structure 2 of the embodiment of the present application can be 700-1000°C. In one embodiment, the filter structure 2 is made of aluminum alloy.

[0052] It should be noted that the filter structure 2 of the embodiment of the present application can be applied to square batteries, cylindrical batteries or other types of single batteries. The drawings of the present application only show the application of the filter structure 2 on square batteries, and in actual applications, those skilled in the art can also apply the filter structure 2 to cylindrical batteries, which is not limited here. In addition, in actual applications, the preset pressure of the explosion-proof valve 1 is usually 1.0Mpa, that is, when the pressure in the shell 3 is greater than 1.0Mpa, the explosion-proof valve 1 opens to release pressure. It is understandable that, under normal circumstances, there will be a certain error in the preset pressure, and the error is usually ±0.1Mpa. It should be noted that the embodiment of the present application does not limit the preset pressure of the explosion-proof valve 1, and those skilled in the art can also adjust the preset pressure of the explosion-proof valve 1 according to actual needs.

[0053] In practical applications, since the high-temperature flue gas contains particles of different sizes, in the process of the collision between the particles and the filter 21, the particles with larger sizes will be intercepted first, while the particles with smaller sizes may be discharged through the mesh 22 of the filter 21. Based on this, in some optional embodiments of the present application, the filter 21 is provided with 2-6 layers, wherein the spacing between two adjacent layers of filter 21 along the emission direction of the flue gas is n, satisfying 2≤n≤3mm. In this way, on the one hand, compared with the single-layer filter 21, the temperature and kinetic energy of the particles can be continuously reduced through multiple collisions between the particles and the multi-layer filter 21, which is beneficial to improve the interception effect of the particles. On the other hand, while satisfying the interception effect, the overall height of the filter structure 2 can be made smaller to avoid affecting the installation of other components in the battery pack.

[0054] It is understandable that as the number of layers of the filter 21 increases, the interception effect of particulate matter is improved, but the processing difficulty and cost of the filter structure 2 increase. As the spacing between two adjacent layers of filter 21 along the flue gas emission direction decreases, the filter structure 2 can be miniaturized, but the processing difficulty of the filter structure 2 increases. Based on a comprehensive consideration of the interception effect, processing difficulty and cost, the filter of the embodiment of the present application can be 2-6 layers, and the spacing between two adjacent layers of filter 21 along the flue gas emission direction, that is, the first direction X, can be 2-3mm. Of course, those skilled in the art can also adjust the number of layers of the filter 21 and the spacing between two adjacent layers of filter 21 along the flue gas emission direction, that is, the first direction X, according to actual needs, and are not limited here.

[0055] In practical applications, since the filter structure 2 is arranged to protrude from the surface of the shell 3, and the battery pack includes other components in addition to the single battery, such as a bus, a protective circuit board, etc. In order to avoid the filter structure 2 affecting the arrangement of other components, the filter structure 2 needs to be as miniaturized as possible. In some optional embodiments of the present application, the height of the filter structure 2 along the emission direction of the flue gas, that is, the first direction X, is h, satisfying 8≤h≤12mm. In one embodiment, the filter structure 2 is provided with three layers of filter screens 21, and along the emission direction of the flue gas, that is, the first direction X, the spacing between the three layers of filter screens 21 is 3mm, 2mm, and 2mm respectively. The thickness of each layer of filter screen 21 along the first direction X is 1mm, and the height of the filter structure 2 along the first direction X is 10mm.

[0056] In some optional embodiments of the present application, such as Figure 5 As shown, among the two adjacent layers of filter screens 21, the first filter screen 211 is arranged close to the explosion-proof valve 1, and the second filter screen 212 is arranged away from the explosion-proof valve 1; the first filter screen 211 is provided with a first mesh hole 221, and the first mesh hole 221 has a first center line; the second filter screen 212 is provided with a second mesh hole 222, and the second mesh hole 222 has a second center line, and the second center line coincides with the first center line.

[0057] In the embodiment of the present application, since the first center line of the first mesh 221 of the first filter 211 coincides with the second center line of the second mesh 222 of the first filter 211, that is, the meshes 22 of the two adjacent layers of filter 21 are aligned. On the basis of satisfying the particle interception effect, such a multi-layer filter 21 has a simple structure and is easy to process. It should be noted that the shape and size of the first mesh 221 and the second mesh 222 can be the same or different, which is not limited here, and those skilled in the art can adjust according to actual needs.

[0058] In some optional embodiments of the present application, such as Figure 4 As shown, among the two adjacent layers of filter screens 21, the first filter screen 211 is arranged close to the explosion-proof valve 1, and the second filter screen 212 is arranged away from the explosion-proof valve 1; the first filter screen 211 is provided with a first mesh hole 221, and the first mesh hole 221 has a first center line; the second filter screen 212 is provided with a second mesh hole 222, and the second mesh hole 222 has a second center line, and the second center line is parallel to the first center line and does not overlap.

[0059] In the embodiment of the present application, since the first center line of the first mesh 221 of the first filter 211 is parallel to the second center line of the second mesh 222 of the first filter 211 and does not overlap, the meshes 22 of the two adjacent layers of filter 21 are staggered. Compared with aligned meshes 22, when the meshes 22 of the two adjacent layers of filter 21 are staggered, the flow path of the high-temperature flue gas can be extended, the temperature and kinetic energy of the particulate matter in the high-temperature flue gas can be further reduced, and it is beneficial to improve the interception effect of the particulate matter. It should be noted that the shape and size of the first mesh 221 and the second mesh 222 can be the same or different, and are not limited here. Those skilled in the art can make adjustments according to actual needs.

[0060] In some optional embodiments of the present application, such as Figure 4 As shown, among the two adjacent layers of filter screens 21 , the first filter screen 211 is arranged close to the explosion-proof valve 1 , and the second filter screen 212 is arranged away from the explosion-proof valve 1 ; the first filter screen 211 is provided with a first mesh 221 ; the second filter screen 212 is provided with a second mesh 222 , and the second mesh 222 is the same as the first mesh 221 .

[0061] In the embodiment of the present application, since the first mesh 221 of the first filter 211 is the same as the second mesh 222 of the second filter 212, that is, the shapes and sizes of the meshes 22 of the two adjacent layers of filter screens 21 are the same, the structure of the filter structure 2 can be simplified, which is beneficial to reducing the processing difficulty and processing cost of the filter structure 2.

[0062] In some optional embodiments of the present application, such as Figure 5As shown, among the two adjacent layers of filter screens 21, the first filter screen 211 is arranged close to the explosion-proof valve 1, and the second filter screen 212 is arranged away from the explosion-proof valve 1; the first filter screen 211 is provided with a first mesh hole 221, and the first mesh hole 221 has a first size; the second filter screen 212 is provided with a second mesh hole 222, and the second mesh hole 222 has a second size, and the second size is smaller than the first size.

[0063] In the embodiment of the present application, since the first filter 211 is provided with a first mesh 221, the second filter 212 is provided with a second mesh 222, and the first size of the first mesh 221 is smaller than the second size of the second mesh 222, that is, the sizes of the meshes 22 of the two adjacent layers of filter 21 are successively reduced. Generally, high-temperature flue gas contains particles of different particle sizes, and particles with larger particle sizes are preferentially intercepted compared to particles with smaller particle sizes. Based on this, by setting a multi-layer filter 21 with mesh 22 sizes that decreases successively, particles of different particle sizes can be gradually intercepted, which is conducive to improving the interception effect of particles.

[0064] It should be noted that the first mesh 221 and the second mesh 222 of the embodiment of the present application may be of the same shape or of different shapes, which is not limited here, and those skilled in the art may make a selection according to actual needs.

[0065] In some optional embodiments of the present application, such as Figures 4 to 5 As shown, the filter 21 is provided with mesh 22, which is a circular mesh, and the diameter of the circular mesh is d, which satisfies: 0.1mm≤d≤1.5mm. In this way, the particulate matter in the high-temperature flue gas can be effectively intercepted without affecting the gas emission in the high-temperature flue gas, which is beneficial to improving the safety of the battery.

[0066] It should be noted that a circular mesh means that the cross section of the mesh 22 along the first direction X is circular. Of course, the cross section of the mesh 22 along the first direction X can also be elliptical, square, triangular or other shapes, which are not limited here, and those skilled in the art can choose according to actual needs. In addition, the mesh 22 is usually provided with a plurality of meshes, and the embodiment of the present application does not limit the specific number of the meshes 22. The plurality of meshes 22 can be arranged at uniform intervals or at non-uniform intervals.

[0067] In some optional embodiments of the present application, such as Figures 3 to 5 As shown, the filter structure 2 further includes a mounting member 23 ; the mounting member 23 is connected to the housing 3 and is disposed around the circumference of the explosion-proof valve 1 ; the filter screen 21 is connected to the mounting member 23 .

[0068] In the embodiment of the present application, since the mounting member 23 is provided, the mounting member 23 is arranged around the circumference of the explosion-proof valve 1, and the filter screen 21 is connected to the mounting member 23, the explosion-proof valve 1 can be placed in a closed space formed by the mounting member 23 and the filter screen 21. In this way, when the explosion-proof valve 1 is depressurized, the high-temperature flue gas can only be discharged from the filter screen 21, so that the particulate matter in the high-temperature flue gas can be effectively intercepted.

[0069] In practical applications, the housing 3 usually includes a box body 31 and a cover plate 32. The box body 31 is provided with a receiving cavity with an opening, the battery cell is provided in the receiving cavity, and the cover plate 32 covers the opening. The mounting hole 321 is provided on the cover plate 32 and is connected to the receiving cavity. The explosion-proof valve 1 is provided on the mounting hole 321. The filter structure 2 is provided on the side of the cover plate 32 away from the battery cell and at least covers the explosion-proof valve 1. In one embodiment, the filter structure 2 and the cover plate 32 are both made of aluminum alloy, and the two are connected by welding. In this way, the welding depth between the filter structure 2 and the cover plate 32 can be increased, thereby improving the structural strength around the mounting hole 321, effectively avoiding the rupture around the mounting hole 321 when the explosion-proof valve 1 is depressurized, and facilitating the secondary processing of the cover plate 32.

[0070] Specifically, the mounting member 23 includes a flange portion 231 and a cylindrical portion 232 which are sequentially arranged along the emission direction of the smoke; the flange portion 231 is connected to the housing 3; the cylindrical portion 232 has an inner wall, and the filter screen 21 is connected to the inner wall. In this way, by providing the flange portion 231, the connection area between the mounting member 23 and the housing 3 can be increased, which is conducive to improving the connection reliability between the mounting member 23 and the housing 3.

[0071] It should be noted that the flange portion 231, the cylindrical portion 232 and the filter screen 21 can be formed separately and then connected, such as by welding, or can be formed in one piece, such as by printing in one piece using a 3D printing process. It is understandable that when the flange portion 231, the cylindrical portion 232 and the filter screen 21 are an integrated structure, the overall structural strength of the filter structure 2 can be improved.

[0072] In summary, the single cell provided in the embodiment of the present application has at least the following advantages:

[0073] In the embodiment of the present application, the single cell includes: a battery cell, a shell, an explosion-proof valve and a filter structure; the battery cell is arranged in the shell; the shell is provided with a mounting hole, and the explosion-proof valve is arranged in the mounting hole; the filter structure is arranged outside the shell and at least covers the explosion-proof valve, and the filter structure includes at least two layers of filter screens, and the filter screen is used to intercept particulate matter in the flue gas. Since the filter structure is provided, and the filter structure includes at least two layers of filter screens. In this way, on the one hand, when the battery cell has thermal runaway and generates a large amount of high-temperature flue gas, the explosion-proof valve opens to release pressure, wherein the gas in the high-temperature flue gas can be discharged from the filter screen, thereby achieving pressure relief; the temperature and kinetic energy of the particulate matter in the high-temperature flue gas are reduced during the collision with the filter screen, so that the particulate matter is effectively intercepted, and the particulate matter is effectively prevented from splashing onto other single cells that have not experienced thermal runaway and causing thermal runaway, which is beneficial to improving the safety of the use of the single cell. On the other hand, since the filter screen is provided with at least two layers, the temperature and kinetic energy of the particulate matter in the high-temperature flue gas can be further reduced, thereby improving the interception effect of the particulate matter and further improving the safety of the use of the single cell. In addition, when the explosion-proof valve is separated from the mounting hole, the filtering structure can limit the explosion-proof valve, thereby effectively avoiding the problem of mechanical damage to other single cells caused by the explosion-proof valve being separated from the mounting hole.

[0074] An embodiment of the present application also provides a battery pack, which includes: any of the above-mentioned single cells.

[0075] In actual applications, the battery pack also includes a liquid cooling component, which is arranged adjacent to the single cell. When a single cell experiences thermal runaway, on the one hand, the filter structure 2 can reduce the temperature and kinetic energy of the particles in the high-temperature gas, and prevent the particles from splashing onto the surface of other single cells that have not experienced thermal runaway and causing thermal runaway. On the other hand, the liquid cooling component can take away most of the heat of the single cell through heat exchange, and can prevent the heat from diffusing to other single cells that have not experienced thermal runaway and causing thermal runaway. That is, under the joint action of the filter structure 2 and the liquid cooling component, the probability of thermal runaway of the single cell can be effectively reduced. In this case, only a circular frame can be used between two adjacent single cells, without the need for aerogel, which is beneficial to reducing the assembly cost of the battery pack.

[0076] It should be noted that in the embodiment of the present application, the structure of the single cell is the same as the structure of the single cell in any of the above embodiments, and its beneficial effects are also similar, which will not be elaborated here.

[0077] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the utility model. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0078] Although the embodiments of the present invention have been shown and described, those skilled in the art will appreciate that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the claims and their equivalents.

Claims

1. A single cell battery, characterized in that: The single cell battery comprises: a battery core, a housing (3), an explosion-proof valve (1) and a filtering structure (2); The battery core is arranged in the housing (3); The housing (3) is provided with a mounting hole (321), and the explosion-proof valve (1) is arranged in the mounting hole (321); The filtering structure (2) is arranged outside the housing (3) and at least covers the explosion-proof valve (1); the filtering structure (2) comprises at least two layers of filter screens (21); and the filter screens (21) are used to intercept particulate matter in the smoke.

2. The single cell according to claim 1, characterized in that: The filter screen (21) is provided with 2 to 6 layers.

3. The single cell according to claim 1, characterized in that: Of the two adjacent layers of filter screens (21), the one disposed close to the explosion-proof valve (1) is the first filter screen (211), and the one disposed away from the explosion-proof valve (1) is the second filter screen (212); The first filter screen (211) is provided with a first mesh hole (221), and the first mesh hole (221) has a first center line; The second filter screen (212) is provided with a second mesh hole (222), the second mesh hole (222) has a second center line, and the second center line coincides with the first center line.

4. The single cell according to claim 1, characterized in that: Of the two adjacent layers of filter screens (21), the one disposed close to the explosion-proof valve (1) is the first filter screen (211), and the one disposed away from the explosion-proof valve (1) is the second filter screen (212); The first filter screen (211) is provided with a first mesh hole (221), and the first mesh hole (221) has a first center line; The second filter screen (212) is provided with a second mesh hole (222), the second mesh hole (222) has a second center line, and the second center line is parallel to and does not overlap with the first center line.

5. The single cell according to claim 1, characterized in that: Of the two adjacent layers of filter screens (21), the one disposed close to the explosion-proof valve (1) is the first filter screen (211), and the one disposed away from the explosion-proof valve (1) is the second filter screen (212); The first filter screen (211) is provided with a first mesh (221); The second filter screen (212) is provided with second mesh holes (222), and the second mesh holes (222) are the same as the first mesh holes (221).

6. The single cell according to claim 1, characterized in that: Of the two adjacent layers of filter screens (21), the one disposed close to the explosion-proof valve (1) is the first filter screen (211), and the one disposed away from the explosion-proof valve (1) is the second filter screen (212); The first filter screen (211) is provided with a first mesh (221), and the first mesh (221) has a first size; The second filter screen (212) is provided with second mesh holes (222), the second mesh holes (222) have a second size, and the second size is smaller than the first size.

7. The single cell according to claim 1, characterized in that: The filter screen (21) is provided with mesh holes (22), the mesh holes (22) are circular mesh holes, the diameter of the circular mesh holes is d, and satisfies: 0.1 mm≤d≤1.5 mm.

8. The single cell according to claim 1, characterized in that: The filtering structure (2) further comprises a mounting member (23); The mounting member (23) is connected to the housing (3) and is arranged around the circumference of the explosion-proof valve (1); The filter screen (21) is connected to the mounting member (23).

9. The single cell according to claim 8, characterized in that: The mounting member (23) comprises a flange portion (231) and a cylindrical portion (232) which are sequentially arranged along the emission direction of smoke; The flange portion (231) is connected to the housing (3); The cylindrical portion (232) has an inner wall, and the filter screen (21) is connected to the inner wall.

10. The single cell according to claim 1, characterized in that: The height of the filtering structure (2) along the emission direction of smoke is h, satisfying 8≤h≤12mm.

11. The single cell according to claim 1, characterized in that: The distance between two adjacent layers of filter screens (21) along the flue gas discharge direction is n, satisfying 2≤n≤3mm.

12. A battery pack, characterized in that: The battery pack comprises: a single cell as described in any one of claims 1-11.

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