Battery monomer, battery pack and power utilization device

Abstract

The utility model provides a battery monomer, a battery pack and a power utilization device, and relates to the technical field of batteries. Each single battery comprises a shell, an anti-explosion valve and a patch, a containing cavity is defined by the shell, the shell comprises a pressure relief channel penetrating through the shell, the pressure relief channel comprises a first pressure relief hole and a second pressure relief hole, and the ends, facing the containing cavity, of the first pressure relief hole and the second pressure relief hole are communicated; the first hole wall of the first pressure relief hole protrudes out of the second pressure relief hole relative to the second hole wall of the second pressure relief hole, the first hole wall of the first pressure relief hole is connected with the second hole wall of the second pressure relief hole through a connecting face, and the anti-explosion valve is arranged in the first pressure relief hole and connected with the connecting face. The patch is connected with the side, back to the containing cavity, of the shell, and the patch covers the second pressure relief hole. The pressure relief channel adopts a two-section design, so that the structural strength of the position where the pressure relief channel of the shell is located is improved, and the risk that the shell is torn during pressure relief during thermal runaway is reduced. And the thickness of the pressure relief channel of the shell is reduced, so that the energy density of the single battery is improved.

Description

Technical Field

[0001] This application relates to the field of battery technology, and in particular to a battery cell, battery pack and power supply device. Background Technology

[0002] A battery cell typically consists of a casing and a cover. To achieve thermoelectric separation, an explosion-proof valve is usually installed on the casing. Specifically, mounting holes are provided on the casing, and these holes are divided into four segments with gradually increasing cross-sectional areas, pointing from the inside of the casing to the outside. The explosion-proof valve is located in the second segment, and a protective patch for the valve is located in the fourth segment. However, the large number of mounting hole segments reduces the structural strength of the casing at these locations, increasing the risk of casing tearing during thermal runaway and pressure relief. Furthermore, to accommodate the required number of mounting hole segments, the casing thickness at these locations is relatively large, leading to a decrease in the energy density of the battery cell. Utility Model Content

[0003] In view of this, this application provides a battery cell, a battery pack, and an electrical device to solve the problems of decreased structural strength of the casing at the mounting hole location, resulting in a higher risk of casing tearing, and increased thickness of the casing at the mounting hole location, resulting in decreased energy density of the battery cell.

[0004] According to a first aspect of this application, a battery cell is provided, the battery cell including a housing, an explosion-proof valve and a patch, the housing enclosing a receiving cavity, the housing including a pressure relief channel penetrating the housing, the pressure relief channel including a first pressure relief hole and a second pressure relief hole, the first pressure relief hole and the second pressure relief hole communicating with one end facing the receiving cavity;

[0005] The first wall of the first pressure relief hole protrudes outward relative to the second wall of the second pressure relief hole. The first wall of the first pressure relief hole and the second wall of the second pressure relief hole are connected by a connecting surface. The explosion-proof valve is disposed in the first pressure relief hole and is connected to the connecting surface.

[0006] The patch is connected to the side of the housing opposite to the receiving cavity, and the patch covers the second pressure relief hole.

[0007] Preferably, a protrusion is provided on one of the connecting surface and the explosion-proof valve, and a groove is formed on the other of the connecting surface and the explosion-proof valve, with the protrusion located in the groove.

[0008] Preferably, the protrusion is an annular structure with its ends connected, and the groove is an annular groove with its ends connected.

[0009] Preferably, the protrusion is located in the middle of the connecting surface or at the end of the connecting surface near the second hole wall.

[0010] Preferably, one of the connecting surface and the explosion-proof valve is provided with a plurality of protrusions, and the other of the connecting surface and the explosion-proof valve is formed with a plurality of grooves, the plurality of grooves and the plurality of protrusions corresponding one to one, and the protrusions are disposed in the corresponding grooves.

[0011] Preferably, the protrusion includes a mating surface, a reference surface, and an arc-shaped surface. The mating surface is located on the side of the protrusion opposite to the connecting surface, and the reference surface is located on the side of the protrusion opposite to the first hole wall. The mating surface and the reference surface are connected by the arc-shaped surface.

[0012] Preferably, the first hole wall includes a guide surface, and the angle between the guide surface and the connecting surface is greater than 90 degrees.

[0013] Preferably, the first hole wall further includes a connecting surface, and the guide surface is connected to the connecting surface through the connecting surface, and the guide surface is perpendicular to the connecting surface.

[0014] Preferably, the distance between the outer wall of the explosion-proof valve and the wall of the first hole is a first distance, which is greater than or equal to 0.001 mm and less than or equal to 0.5 mm.

[0015] Preferably, the housing includes a bottom plate and a surrounding plate, the surrounding plate being disposed around the edge of the bottom plate, the bottom plate being perpendicular to a predetermined direction, and the first pressure relief hole and the second pressure relief hole both extending along the predetermined direction;

[0016] The distance between the surface of the explosion-proof valve facing the cavity and the surface of the base plate facing the cavity in the predetermined direction is a second distance, and the ratio of the second distance to the first distance is greater than or equal to 0.1 and less than or equal to 280.

[0017] According to a second aspect of this application, a battery pack is provided, the battery pack comprising the aforementioned battery cells.

[0018] According to a third aspect of this application, an electrical device is provided, the electrical device comprising the battery pack described above.

[0019] The battery cell of this application includes a housing and an explosion-proof valve. The housing encloses a receiving cavity and includes a pressure relief channel, which includes a first pressure relief hole and a second pressure relief hole. The first pressure relief hole and the second pressure relief hole communicate with each other at their ends facing the receiving cavity. The first wall of the first pressure relief hole protrudes outward relative to the second wall of the second pressure relief hole. The first wall of the first pressure relief hole and the second wall of the second pressure relief hole are connected by a connecting surface. The explosion-proof valve is disposed in the first pressure relief hole and connected to the connecting surface. A patch is connected to the side of the housing opposite to the receiving cavity, and the patch covers the second pressure relief hole. Thus, the first pressure relief hole is used to install the explosion-proof valve, and the second pressure relief hole is used to provide space between the explosion-proof valve and the patch. The pressure relief channel adopts a two-stage design, which improves the structural strength of the housing at the location of the pressure relief channel and reduces the risk of housing tearing during thermal runaway pressure relief. At the same time, since the pressure relief channel only includes the first and second pressure relief holes, the thickness of the housing at the location of the pressure relief channel can be reduced, thereby improving the energy density of the battery cell. Attached Figure Description

[0020] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 A three-dimensional structural schematic diagram of a battery cell according to Embodiment 1 of this utility model is shown;

[0022] Figure 2 An exploded view of a single battery cell according to Embodiment 1 of this utility model is shown;

[0023] Figure 3 A cross-sectional view of a battery cell according to Embodiment 1 of this utility model is shown;

[0024] Figure 4 Show Figure 3 Enlarged view of section A;

[0025] Figure 5 A partial cross-sectional view of the casing of a battery cell according to Embodiment 1 of this utility model is shown.

[0026] Figure 6 A partial cross-sectional view of a battery cell according to Embodiment 2 of this utility model is shown;

[0027] Figure 7 A partial cross-sectional view of the casing of a battery cell according to Embodiment 2 of this utility model is shown.

[0028] Figure 8A partial cross-sectional view of a battery cell according to Embodiment 3 of this utility model is shown;

[0029] Figure 9 A partial cross-sectional view of a battery cell according to Embodiment 4 of this utility model is shown;

[0030] Figure 10 A partial cross-sectional view of a battery cell according to Embodiment 5 of this utility model is shown.

[0031] Icons: 1-Shell; 11-Base plate; 12-Enclosure plate; 13-Pressure relief channel; 131-First pressure relief hole; 132-Second pressure relief hole; 14-Protrusion; 2-Explosion-proof valve; 21-Groove; 3-Patch; 4-Receiving cavity; S1-First hole wall; S11-Guide surface; S12-Connecting surface; S2-Second hole wall; S3-Connecting surface; S4-Mating surface; S5-Reference surface; S6-Arc-shaped surface; L-Predetermined direction. Detailed Implementation

[0032] The following detailed embodiments are provided to help the reader gain a comprehensive understanding of the methods, apparatus, and / or systems described herein. However, various changes, modifications, and equivalents of the methods, apparatus, and / or systems described herein will be apparent after understanding the disclosure of this application. For example, the order of operations described herein is merely illustrative and is not limited to the order set forth herein; changes that will be apparent after understanding the disclosure of this application are possible, except for operations that must occur in a specific order. Furthermore, for clarity and brevity, descriptions of features known in the art may be omitted.

[0033] The features described herein may be implemented in different forms and should not be construed as being limited to the examples described herein. Rather, the examples described herein have been provided merely to illustrate some of the many feasible ways of implementing the methods, apparatus, and / or systems described herein that will be apparent upon understanding the disclosure of this application.

[0034] Throughout the specification, when an element (such as a layer, region, or substrate) is described as being "on" another element, "connected to" another element, "bonded to" another element, "on" another element, or "covering" another element, it may be directly "on" another element, "connected to" another element, "bonded to" another element, "on" another element, or "covering" another element, or there may be one or more other elements in between. In contrast, when an element is described as being "directly on" another element, "directly connected to" another element, "directly bonded to" another element, "directly on" another element, or "directly covering" another element, there may be no other elements in between.

[0035] As used herein, the term “and / or” includes any one of the relevant items listed and any combination of any two or more items.

[0036] Although terms such as “first,” “second,” and “third” may be used herein to describe individual components, assemblies, regions, layers, or parts, these components, assemblies, regions, layers, or parts are not limited by these terms. Rather, these terms are used only to distinguish one component, assembly, region, layer, or part from another. Therefore, without departing from the teachings of the examples described herein, the first component, assembly, region, layer, or part referred to as the second component, assembly, region, layer, or part may also be referred to as the second component, assembly, region, layer, or part.

[0037] For ease of description, spatial relation terms such as “above,” “upper,” “below,” and “lower” are used herein to describe the relationship between one element and another, as shown in the accompanying drawings. Such spatial relation terms are intended to include not only the orientation depicted in the drawings but also different orientations of the device during use or operation. For example, if the device in the drawings is flipped, an element described as being “above” or “upper” relative to another element will subsequently be “below” or “lower” relative to that other element. Therefore, the term “above” includes both “above” and “below” orientations depending on the spatial orientation of the device. The device may also be positioned in other ways (e.g., rotated 90 degrees or in other orientations), and the spatial relation terms used herein will be interpreted accordingly.

[0038] The terminology used herein is for the purpose of describing various examples only and is not intended to limit this disclosure. Unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. The terms “comprising,” “including,” and “having” enumerate the stated features, quantities, operations, components, elements, and / or combinations thereof, but do not exclude the presence or addition of one or more other features, quantities, operations, components, elements, and / or combinations thereof.

[0039] Variations in the shapes shown in the accompanying drawings may occur due to manufacturing techniques and / or tolerances. Therefore, the examples described herein are not limited to the specific shapes shown in the accompanying drawings, but include changes in shape that may occur during manufacturing.

[0040] The features of the examples described herein can be combined in various ways that will be apparent upon understanding the disclosure of this application. Furthermore, although the examples described herein have a wide variety of constructions, other constructions are possible, as will be apparent upon understanding the disclosure of this application.

[0041] According to the first aspect of this application, a battery cell is provided, such as Figures 1 to 10 As shown, the battery cell includes a housing 1 and an explosion-proof valve 2. The housing 1 encloses a receiving cavity 4 and includes a pressure relief channel 13. The pressure relief channel 13 includes a first pressure relief hole 131 and a second pressure relief hole 132. The first pressure relief hole 131 and the second pressure relief hole 132 are connected at their ends facing the receiving cavity 4. The first hole wall S1 of the first pressure relief hole 131 protrudes outward relative to the second hole wall S2 of the second pressure relief hole 132. The first hole wall S1 of the first pressure relief hole 131 and the second hole wall S2 of the second pressure relief hole 132 are connected by a connecting surface S3. The explosion-proof valve 2 is disposed in the first pressure relief hole 131 and connected to the connecting surface S3. A patch 3 is connected to the side of the housing 1 opposite to the receiving cavity 4 and covers the second pressure relief hole 132. Thus, the first pressure relief hole 131 is used to install the explosion-proof valve 2, and the second pressure relief hole 132 is used to provide space between the explosion-proof valve 2 and the patch 3. The pressure relief channel 13 adopts a two-section design, which improves the structural strength of the pressure relief channel 13 in the housing 1 and reduces the risk of the housing 1 tearing when thermal runaway occurs and pressure is released. At the same time, the pressure relief channel 13 only includes the first pressure relief hole 131 and the second pressure relief hole 132, and the thickness of the housing 1 at the pressure relief channel 13 can be reduced, thereby improving the energy density of the battery cell.

[0042] Optionally, the shapes of the first pressure relief port 131 and the second pressure relief port 132 can be selected based on the explosion-proof valve 2, for example, as... Figure 1 and Figure 2 As shown, both the first pressure relief hole 131 and the second pressure relief hole 132 can be oblong holes, and the explosion-proof valve 2 is a plate-like structure adapted to the shape of the first pressure relief hole 131. Alternatively, both the first pressure relief hole 131 and the second pressure relief hole 132 can be round holes, and the explosion-proof valve 2 is a circular plate-like structure adapted to the first pressure relief hole 131.

[0043] Furthermore, the individual battery cell also includes a cover plate, such as... Figure 4 As shown, the housing 1 includes a base plate 11 and a surrounding plate 12. The surrounding plate 12 surrounds the base plate 11, and the base plate 11 and the surrounding plate 12 together enclose a receiving cavity 4. An opening is formed at the upper end of the housing 1, and a cover plate is placed over the opening to seal the receiving cavity 4. The base plate 11 has the aforementioned pressure relief channel 13, and the first pressure relief hole 131 and the second pressure relief hole 132 of the pressure relief channel 13 both extend along a predetermined direction L. The patch 3 can be adhered to the surface of the base plate 11 and the surface opposite to the receiving cavity 4 using adhesive.

[0044] Optionally, the structure of the first hole wall S1, the connecting surface S3, and the explosion-proof valve 2 can be selected as needed. The structure of the first hole wall S1, the connecting surface S3, and the explosion-proof valve 2 of this application will be described below in conjunction with Embodiments 1 to 5.

[0045] Example 1

[0046] In this embodiment, as Figure 3 , Figure 4 and Figure 5 As shown, the connecting surface S3 is perpendicular to the predetermined direction L, and the first hole wall S1 is perpendicular to the connecting surface S3. At this time, the side of the explosion-proof valve 2 facing the second pressure relief hole 132 is in contact with the connecting surface S3, and there is a gap between the outer wall of the explosion-proof valve 2 and the first hole wall S1. The distance between the outer wall of the explosion-proof valve 2 and the first hole wall S1 is a first distance a, which is greater than or equal to 0.001mm and less than or equal to 0.5mm, i.e., 0.001mm ≤ a ≤ 0.5mm. For example, the first distance a can be 0.001mm, 0.005mm, 0.007mm, 0.1mm, 0.2mm, 0.25mm, 0.3mm, 0.33mm, 0.4mm, 0.45mm, or 0.5mm, etc. When the first distance a is less than 0.001 mm, the gap between the explosion-proof valve 2 and the first orifice wall S1 is too small, resulting in a low yield rate for the explosion-proof valve 2 in the first pressure relief hole 131. When the first distance a is greater than 0.5 mm, the gap between the explosion-proof valve 2 and the first orifice wall S1 is too large, resulting in a low yield rate for the welding of the explosion-proof valve 2 to the housing 1. By setting the distance a between the outer wall of the explosion-proof valve 2 and the first orifice wall S1 within the above-mentioned range, the yield rate of the explosion-proof valve 2 in the first assembly with the first pressure relief hole 131 and the yield rate of the welding between the explosion-proof valve 2 and the housing 1 can be guaranteed.

[0047] Furthermore, the distance in the predetermined direction L between the surface of the explosion-proof valve 2 facing the receiving cavity 4 and the surface of the base plate 11 facing the receiving cavity 4 is a second distance b. The second distance b is equal to the difference between the depth d of the first pressure relief hole 131 in the predetermined direction L and the thickness c of the explosion-proof valve 2 in the predetermined direction L, i.e., b = cd. The ratio of the second distance b to the first distance a is greater than or equal to 0.02 and less than or equal to 1000, i.e., 0.1 ≤ b / a ≤ 280. When b / a < 0.1, the weld mark formed between the explosion-proof valve 2 and the base plate 11 will be higher than the surface of the housing 1 facing the receiving cavity 4. When b / a > 280, the distance between the surface of the explosion-proof valve 2 facing the receiving cavity 4 and the surface of the base plate 11 facing the receiving cavity 4 is too large, resulting in a low welding yield. By setting the ratio b / a of the second distance b to the first distance a within the above range, it is possible to ensure the welding yield between the housing 1 and the explosion-proof valve 2 while avoiding the weld mark being higher than the surface of the base plate 11 facing the receiving cavity 4.

[0048] Example 2

[0049] In this embodiment, as Figure 6 and Figure 7As shown, the connecting surface S3 is perpendicular to the predetermined direction L, and the first hole wall S1 is perpendicular to the connecting surface S3. At this time, the side of the explosion-proof valve 2 facing the second pressure relief hole 132 is in contact with the connecting surface S3, and there is a gap between the outer wall of the explosion-proof valve 2 and the first hole wall S1.

[0050] Furthermore, a protrusion 14 is provided on one of the connecting surface S3 and the explosion-proof valve 2, and a groove 21 is formed on the other of the connecting surface S3 and the explosion-proof valve 2, with the protrusion 14 located within the groove 21. The protrusion 14 and the groove 21 cooperate to achieve positioning between the first pressure relief hole 131 and the explosion-proof valve 2, facilitating the installation of the explosion-proof valve 2 into the first pressure relief hole 131 through the opening of the housing 1 and the receiving cavity 4. Optionally, the protrusion 14 can be provided on the connecting surface S3, in which case the groove 21 is formed on the explosion-proof valve 2; alternatively, the protrusion 14 can be provided on the explosion-proof valve 2, in which case the groove 21 is formed on the connecting surface S3.

[0051] Furthermore, the number of protrusions 14 and grooves 21 is the same, and the number of protrusions 14 can be one, two, or more. When the number of protrusions 14 is two or more, the multiple protrusions 14 correspond one-to-one with the multiple grooves 21, and the protrusions 14 are disposed in the corresponding grooves 21. The multiple protrusions 14 can be multiple stud-like structures arranged at intervals or continuous annular protrusions.

[0052] When there is only one protrusion 14, and the protrusion 14 is disposed on the connecting surface S3, the protrusion 14 can be located at the end of the connecting surface S3 near the second hole wall S2. The protrusion 14 includes a mating surface S4, a reference surface S5, and an arc-shaped surface S6. The mating surface S4 is located on the side of the protrusion 14 opposite to the connecting surface S3, and the mating surface S4 can be mated to the bottom of the groove 21. The reference surface S5 is located on the side of the protrusion 14 opposite to the first hole wall S1, and the reference surface S5 can be flush with the second hole wall S2. The mating surface S4 and the reference surface S5 are connected by the arc-shaped surface S6. In this way, the mating surface S4 and the reference surface S5 of the protrusion 14 are transitioned by the arc-shaped surface S6, which facilitates the processing of the protrusion 14.

[0053] Preferably, the protrusion 14 can be an annular structure with the ends connected, and the groove 21 can be an annular groove with the ends connected.

[0054] In this embodiment, the distance between the outer wall of the explosion-proof valve 2 and the first hole wall S1 is a first distance a greater than or equal to 0.001 mm and less than or equal to 0.5 mm, i.e., 0.001 mm ≤ a ≤ 0.5 mm. The distance in the predetermined direction L between the surface of the explosion-proof valve 2 facing the receiving cavity 4 and the surface of the bottom plate 11 facing the receiving cavity 4 is a second distance b, the ratio of which to the first distance a is greater than or equal to 0.1 and less than or equal to 280, i.e., 0.1 ≤ b / a ≤ 280. The above structure can achieve the same technical effect as in Embodiment 1, and will not be repeated here.

[0055] Example 3

[0056] In this embodiment, as Figure 8 As shown, the connecting surface S3 is perpendicular to the predetermined direction L, and the first hole wall S1 is perpendicular to the connecting surface S3. The side of the explosion-proof valve 2 facing the second pressure relief hole 132 is in contact with the connecting surface S3, and there is a gap between the outer wall of the explosion-proof valve 2 and the first hole wall S1. A protrusion 14 is provided in the middle of the connecting surface S3, and a groove 21 is formed on the explosion-proof valve 2. The protrusion 14 on the connecting part is disposed in the groove 21. By the cooperation of the protrusion 14 and the groove 21, the positioning between the first pressure relief hole 131 and the explosion-proof valve 2 can be realized, so that the explosion-proof valve 2 can be installed into the first pressure relief hole 131 through the opening of the housing 1 and the receiving cavity 4.

[0057] The protrusion 14 includes a mating surface S4, a reference surface S5, and an arc-shaped surface S6. The mating surface S4 is located on the side of the protrusion 14 opposite to the connecting surface S3, and the mating surface S4 can fit against the bottom of the groove 21. The reference surface S5 is located on the side of the protrusion 14 opposite to the first hole wall S1. The mating surface S4 and the reference surface S5 are connected by the arc-shaped surface S6. In this way, the mating surface S4 and the reference surface S5 of the protrusion 14 are transitioned by the arc-shaped surface S6, which facilitates the processing of the protrusion 14.

[0058] Optionally, a groove 21 may also be formed in the middle of the connecting surface S3. In this case, a protrusion 14 is formed on the explosion-proof valve 2, and the protrusion 14 is disposed in the groove 21.

[0059] Furthermore, the number of protrusions 14 and grooves 21 is the same, and the number of protrusions 14 can be one, two, or more. When the number of protrusions 14 is two or more, the multiple protrusions 14 correspond one-to-one with the multiple grooves 21, and the protrusions 14 are disposed in the corresponding grooves 21. The multiple protrusions 14 can be multiple stud-like structures arranged at intervals or continuous annular protrusions.

[0060] Preferably, the protrusion 14 can be an annular structure with the ends connected, and the groove 21 can be an annular groove with the ends connected.

[0061] In this embodiment, the distance between the outer wall of the explosion-proof valve 2 and the first hole wall S1 is a first distance a greater than or equal to 0.001 mm and less than or equal to 0.5 mm, i.e., 0.001 mm ≤ a ≤ 0.5 mm. The distance in the predetermined direction L between the surface of the explosion-proof valve 2 facing the receiving cavity 4 and the surface of the bottom plate 11 facing the receiving cavity 4 is a second distance b, the ratio of which to the first distance a is greater than or equal to 0.1 and less than or equal to 280, i.e., 0.1 ≤ b / a ≤ 280. The above structure can achieve the same technical effect as in Embodiment 1, and will not be repeated here.

[0062] Example 4

[0063] In this embodiment, as Figure 9 As shown, the connecting surface S3 is perpendicular to the predetermined direction L, and the first hole wall S1 only includes a guide surface S11 that is inclined relative to the connecting surface S3. The angle between the guide surface S11 and the connecting surface S3 is greater than 90 degrees. At this time, the outer wall of the explosion-proof valve 2 is an inclined surface that cooperates with the guide surface S11. The guide surface S11 can guide the explosion-proof valve 2 so that the explosion-proof valve 2 can be installed into the first pressure relief hole 131 through the opening of the housing 1 and the receiving cavity 4.

[0064] Optionally, in this embodiment, the connecting surface S3 may also be provided with a protrusion 14 or a groove 21, and the explosion-proof valve 2 may be provided with a matching groove 21 or a protrusion 14 to further guide the installation of the explosion-proof valve 2.

[0065] Example 5

[0066] In this embodiment, as Figure 10 As shown, the connecting surface S3 is perpendicular to the predetermined direction L. The first hole wall S1 includes a guide surface S11 and a connecting surface S12. The guide surface S11 is connected to the connecting surface S3 through the connecting surface S12. The guide surface S11 is perpendicular to the connecting surface S3, and the angle between the guide surface S11 and the connecting surface S3 is greater than 90 degrees. At this time, the outer wall of the explosion-proof valve 2 can be perpendicular to the connecting surface S3. The guide surface S11 can guide the explosion-proof valve 2 to facilitate its installation into the first pressure relief hole 131.

[0067] In the battery cell of this application, the pressure relief channel 13 adopts a two-section design, which improves the structural strength of the pressure relief channel 13 in the housing 1 and reduces the risk of the housing 1 tearing when thermal runaway occurs and pressure is released. At the same time, the pressure relief channel 13 only includes the first pressure relief hole 131 and the second pressure relief hole 132, and the thickness of the housing 1 at the location of the pressure relief channel 13 can be reduced, thereby improving the energy density of the battery cell.

[0068] According to a second aspect of this application, a battery pack is provided, which includes the aforementioned battery cells and has the same technical effects as the battery cells, which will not be described in detail here.

[0069] According to a third aspect of this application, an electrical device is provided, which includes the aforementioned battery pack. The electrical device has the same technical effects as the battery pack, which will not be described in detail here.

[0070] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model, and are not intended to limit it. Although the utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this utility model.

Claims

1. A battery cell, characterized in that, The battery cell includes a housing (1), an explosion-proof valve (2), and a patch (3). The housing (1) encloses a receiving cavity (4). The housing (1) includes a pressure relief channel (13) that penetrates the housing (1). The pressure relief channel (13) includes a first pressure relief hole (131) and a second pressure relief hole (132). The first pressure relief hole (131) and the second pressure relief hole (132) are connected to the end of the second pressure relief hole (132) facing the receiving cavity (4). The first hole wall (S1) of the first pressure relief hole (131) protrudes outward from the second hole wall (S2) of the second pressure relief hole (132) relative to the second hole wall (S2) of the second pressure relief hole (132). The first hole wall (S1) of the first pressure relief hole (131) and the second hole wall (S2) of the second pressure relief hole (132) are connected by a connecting surface (S3). The explosion-proof valve (2) is disposed in the first pressure relief hole (131) and is connected to the connecting surface (S3). The patch (3) is connected to the side of the housing (1) opposite to the receiving cavity (4), and the patch (3) covers the second pressure relief hole (132).

2. The battery cell according to claim 1, characterized in that, A protrusion (14) is provided on one of the connecting surface (S3) and the explosion-proof valve (2), and a groove (21) is formed on the other of the connecting surface (S3) and the explosion-proof valve (2), with the protrusion (14) located in the groove (21).

3. The battery cell according to claim 2, characterized in that, The protrusion (14) is an annular structure with its ends connected, and the groove (21) is an annular groove with its ends connected.

4. The battery cell according to claim 2, characterized in that, The protrusion (14) is disposed in the middle of the connecting surface (S3) or at the end of the connecting surface (S3) near the second hole wall (S2).

5. The battery cell according to claim 2, characterized in that, One of the connecting surface (S3) and the explosion-proof valve (2) is provided with a plurality of protrusions (14), and the other of the connecting surface (S3) and the explosion-proof valve (2) is provided with a plurality of grooves (21). The plurality of grooves (21) and the plurality of protrusions (14) correspond one-to-one, and the protrusions (14) are disposed in the corresponding grooves (21).

6. The battery cell according to claim 2, characterized in that, The protrusion (14) includes a mating surface (S4), a reference surface (S5), and an arc-shaped surface (S6). The mating surface (S4) is located on the side of the protrusion (14) opposite to the connecting surface (S3), and the reference surface (S5) is located on the side of the protrusion (14) opposite to the first hole wall (S1). The mating surface (S4) and the reference surface (S5) are connected by the arc-shaped surface (S6).

7. The battery cell according to claim 1 or 2, characterized in that, The first hole wall (S1) includes a guide surface (S11), and the angle between the guide surface (S11) and the connecting surface (S3) is greater than 90 degrees.

8. The battery cell according to claim 7, characterized in that, The first hole wall (S1) further includes a connecting surface (S12), and the guide surface (S11) is connected to the connecting surface (S3) through the connecting surface (S12). The guide surface (S11) is perpendicular to the connecting surface (S3).

9. The battery cell according to any one of claims 1-6, characterized in that, The distance between the outer wall of the explosion-proof valve (2) and the first hole wall (S1) is a first distance (a), which is greater than or equal to 0.001 mm and less than or equal to 0.5 mm.

10. The battery cell according to claim 9, characterized in that, The housing (1) includes a bottom plate (11) and a surrounding plate (12). The surrounding plate (12) is arranged around the edge of the bottom plate (11). The bottom plate (11) is perpendicular to a predetermined direction (L). The first pressure relief hole (131) and the second pressure relief hole (132) both extend along the predetermined direction (L). The distance between the surface of the explosion-proof valve (2) facing the cavity (4) and the surface of the base plate (11) facing the cavity (4) in the predetermined direction (L) is a second distance (b), and the ratio of the second distance (b) to the first distance (a) is greater than or equal to 0.1 and less than or equal to 280.

11. A battery pack, characterized in that, The battery pack comprises the battery cells according to any one of claims 1-10.

12. An electrical appliance, characterized in that, The electrical device includes the battery pack as described in claim 11.

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