Battery cell, battery, and electric device

Abstract

The utility model belongs to battery technical field discloses a kind of battery monomer, battery and electric equipment, battery monomer includes shell, electric core and support piece.Shell includes the first wall and second wall being connected with each other, the area of first wall is greater than the area of second wall, first wall has the center line extending along first direction, first direction is the height direction of first wall;Electric core includes the electric core body being located in shell, and the lug is connected in electric core body;Support piece is located between first wall and electric core body, and there is spacing between the normal projection area of support piece on first wall and center line;Support piece includes main support part and thickening portion connected to main support part, in first direction, thickening portion is located between main support part and lug, and the thickness of thickening portion is greater than the thickness of main support part.The battery monomer, battery and electric equipment provided by the utility model reduce the risk of lithium precipitation, with high reliability and safety.

Description

Technical Field

[0001] This utility model relates to the field of battery technology, and in particular to a battery cell, a battery, and an electrical device. Background Technology

[0002] During normal charge and discharge cycles, a certain amount of expansion force is generated inside the battery cell. In the later stages of the cycle, the side reactions of the electrolyte increase, and gas is generated inside the battery cell, which further aggravates the expansion of the battery cell.

[0003] In related technologies, a battery cell includes a casing and a cell housed within the casing. The expansion of a battery cell is primarily characterized by greater expansion in the central region and less expansion in the side regions. In a battery module or battery pack, multiple battery cells are placed side-by-side. Adjacent cells mutually inhibit each other's expansion, resulting in greater pressure on the central region of the cell and less pressure on the side regions. This uneven pressure distribution leads to stress concentration within the battery cell, increasing the risk of lithium plating and lowering the cell's safety. While adding support bumps within the casing can reduce the risk of lithium plating, the expansion of the areas connecting to the tabs on the sides is less due to the pull of the tabs compared to other areas. This means the support bumps cannot effectively support the area where the battery cell connects to the tabs, and stress concentration still occurs within the battery cell. Utility Model Content

[0004] The first objective of this invention is to provide a battery cell that solves the problem of lithium plating caused by stress concentration in the prior art.

[0005] The second objective of this invention is to provide a battery with high reliability and safety.

[0006] The third objective of this utility model is to provide an electrical device with high safety.

[0007] Based on the above concept, the technical solution adopted by this utility model is as follows:

[0008] Battery cells, including:

[0009] The shell includes a first wall and a second wall that are connected to each other, the area of ​​the first wall is larger than the area of ​​the second wall, and the first wall has a centerline extending along a first direction, the first direction being the height direction of the first wall;

[0010] A battery cell includes a battery cell body disposed within the housing, the battery cell body being connected to tabs;

[0011] A support member is disposed between the first wall and the cell body. The support member has a gap between its orthographic projection area on the first wall and the center line. The support member includes a main support portion and a thickened portion connected to the main support portion. In the first direction, the thickened portion is located between the main support portion and the electrode tab. The thickness of the thickened portion is greater than the thickness of the main support portion.

[0012] In one embodiment, the dimension of the thickened portion in the first direction is w, and the length of the tab is L, where w = L.

[0013] In one embodiment, the thickness of the main support portion is T1, and the thickness of the thickened portion is T2, satisfying the relationship: T1 < T2 ≤ 1.5T1;

[0014] In one embodiment, the main support portion gradually increases in size in a second direction along the center line pointing towards the support member, wherein the second direction is the thickness direction of the first wall.

[0015] In one embodiment, the maximum dimension of the thickened portion in the second direction is greater than the maximum dimension of the main support portion in the second direction;

[0016] And / or, the minimum dimension of the thickened portion in the second direction is greater than the minimum dimension of the main support portion in the second direction.

[0017] In one embodiment, the main support and the thickened portion are an integral structure.

[0018] In one embodiment, the maximum dimension of the orthographic projection area of ​​the support member on the first wall in the third direction is e, and the dimension of the housing in the third direction is b, wherein e and b satisfy the relationship: 10%b≤e≤25%b; wherein the third direction is the width direction of the first wall;

[0019] And / or,

[0020] The maximum dimension of the orthographic projection area of ​​the support member on the first wall in the first direction is h1, and the dimension of the shell in the first direction is h2, wherein h1 and h2 satisfy the relationship: 50%h2≤h1≤h2;

[0021] And / or,

[0022] The minimum distance between the orthographic projection area of ​​the support member on the first wall and the center line is L, and the dimension of the shell in the third direction is b, wherein L and b satisfy the relationship: L = b.

[0023] In one embodiment, the minimum distance between the orthographic projection area of ​​the support member on the first wall and the second wall is d, the dimension of the shell in the third direction is b, and d and b satisfy the relationship: d = b; and / or, the value of d ranges from 5mm to 20mm.

[0024] And / or,

[0025] The minimum distance between the orthographic projection area of ​​the support member on the first wall and the edge of the top of the shell is h3, the dimension of the shell in the first direction is h2, and h3 and h2 satisfy the relationship: h3=h2; and / or, the value of h3 is in the range of 8mm-150mm.

[0026] Batteries, including battery cells as described above.

[0027] Electrical equipment includes the battery cell described above; or, the electrical equipment includes the battery described above.

[0028] The beneficial effects of this utility model are:

[0029] The battery cell provided by this utility model has a casing including a first wall and a second wall. The area of ​​the first wall is larger than that of the second wall, allowing the first wall to face the surface with a larger cell area. A support member is provided between the first wall and the cell body, and the support member has a gap between the orthographic projection area S of the first wall and the center line of the first wall. When the cell body expands, the area of ​​the cell body with a larger expansion amplitude directly contacts the first wall, while the area of ​​the cell body with a smaller expansion amplitude contacts the main support part of the support member. Due to the pulling of the tabs, the area of ​​the cell body with an even smaller expansion amplitude contacts the thickened part of the support member. Since the support member has a certain thickness, the pressure difference between the part of the cell in contact with the first wall and the part of the cell in contact with the support member is reduced, resulting in a more uniform pressure distribution in the cell, reducing the risk of stress concentration in the cell, thereby reducing the risk of lithium plating, improving the reliability of the battery cell under high power output and high impact environments, and thus improving the safety of the battery cell.

[0030] The batteries provided have high reliability and safety;

[0031] The electrical equipment provided has a high level of safety. Attached Figure Description

[0032] To more clearly illustrate the technical solutions in the embodiments of this utility model, the drawings used in the description of the embodiments of this utility model will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on the content of the embodiments of this utility model and these drawings without creative effort.

[0033] Figure 1 This is a schematic diagram of the structure of a battery cell provided in an embodiment of the present invention;

[0034] Figure 2 This is a first cross-sectional view of a battery cell provided in an embodiment of the present invention;

[0035] Figure 3 This is a partially enlarged top view of a battery cell according to an embodiment of the present invention;

[0036] Figure 4 This is a second cross-sectional view of a battery cell provided in an embodiment of the present invention;

[0037] Figure 5 This is a partially enlarged top view of another battery cell provided in an embodiment of the present invention;

[0038] Figure 6 This is a cross-sectional view of a battery cell without showing the battery cell, provided in one embodiment of this utility model;

[0039] Figure 7 This is a third cross-sectional view of a battery cell provided in an embodiment of the present invention;

[0040] Figure 8 This is a cross-sectional view of another battery cell provided in one embodiment of the present invention when the battery cell is not shown;

[0041] Figure 9 This is a cross-sectional view of a battery cell without showing the battery cell, provided in another embodiment of this utility model;

[0042] Figure 10 This is a cross-sectional view of a battery cell without showing the battery cell, provided in one embodiment of the present invention.

[0043] In the picture:

[0044] 1. Shell; 11. First wall; 111. Center line; 12. Second wall; 2. Battery cell; 21. Battery cell body; 22. Electrode; 3. Support component; 31. Main support part; 32. Thickened part; S. Orthographic projection area; X. First direction; Y. Second direction; Z. Third direction. Detailed Implementation

[0045] To make the technical problem solved by this utility model, the technical solution adopted, and the technical effect achieved clearer, the technical solution of this utility model will be further described below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are merely for explaining this utility model and not for limiting it. Furthermore, it should be noted that, for ease of description, only the parts related to this utility model are shown in the accompanying drawings, not all of them.

[0046] It should be understood that the phrase "one embodiment" or "an embodiment" throughout the specification means that a specific feature, structure, or characteristic related to the embodiment is included in at least one embodiment of the present invention. Therefore, "in one embodiment" or "in an embodiment" appearing throughout the specification do not necessarily refer to the same embodiment. Furthermore, these specific features, structures, or characteristics can be combined in any suitable manner in one or more embodiments.

[0047] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0048] In the description of this utility model, unless otherwise explicitly specified and limited, the terms "connected," "linked," and "fixed" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0049] In this utility model, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature. In the description of this embodiment, unless otherwise specified, "multiple" specifically refers to two or more.

[0050] In the description of this embodiment, the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential," etc., are based on the orientation or positional relationships shown in the accompanying drawings and are only for ease of description and simplification of operation. They do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. Furthermore, the terms "first" and "second" are merely used for distinction in description and have no special meaning.

[0051] It should be noted that when a component is referred to as "fixed to" or "set on" another component, it can be directly on the other component or it can be located in between the component.

[0052] The technical solution of this utility model will be further described below with reference to the accompanying drawings and specific embodiments.

[0053] This embodiment provides a single battery cell that can better support the cell 2 while reducing the risk of lithium plating, thus providing higher safety.

[0054] For example, such as Figures 1 to 3 As shown, a single battery cell includes a housing 1, a battery cell 2, and a support member 3. Both the battery cell 2 and the support member 3 are disposed within the housing 1.

[0055] like Figure 1 As shown, the housing 1 includes a first wall 11 and a second wall 12 connected to each other. The area of ​​the first wall 11 is larger than the area of ​​the second wall 12. Optionally, the battery cell is typically rectangular in shape and has a large face and a small face, where the first wall 11 corresponds to the large face of the battery cell, and the second wall 12 corresponds to the small face of the battery cell. In this embodiment, there are two first walls 11 and two second walls 12, with the two first walls 11 facing each other and the two second walls 12 facing each other.

[0056] like Figure 2As shown, the first wall 11 has a centerline 111 extending along a first direction X, and the centerline 111 passes through the center of the first wall 11 in a third direction Z. The first direction X is the height direction of the first wall 11, i.e., the height direction of the battery cell, the casing 1, or the cell 2; the third direction Z is the length direction of the first wall 11, i.e., the length direction of the battery cell, the casing 1, or the cell 2. This embodiment also defines a second direction Y, where the second direction Y is the thickness direction (i.e., the width direction of the first wall 11), i.e., the thickness direction (i.e., the width direction of the battery cell), the thickness direction (i.e., the width direction of the casing 1), or the thickness direction (i.e., the width direction of the cell 2). Any two of the first direction X, the second direction Y, and the third direction Z are perpendicular to each other.

[0057] For example, such as Figure 2 As shown, the battery cell 2 in this embodiment includes a battery cell body 21 disposed within a housing 1, and the battery cell body 21 is connected to a tab 22. Optionally, the tab 22 is used for electrical connection with the terminal post on the cover plate of the battery cell to perform electrical energy input or output. In some embodiments, the tab 22 is connected to one end face of the battery cell body 21 in the height direction, and the tab 22 has a certain height. In this embodiment, the area where the battery cell body 21 is connected to the tab 22 is called the tab 22 connection area. The electrodes of the battery cell body 21 in the tab 22 connection area are all connected to the tab 22, so that the tab 22 binds the electrodes and limits the expansion range of the electrodes to a certain extent.

[0058] For example, such as Figure 1 As shown, in this embodiment, the support member 3 is disposed between the first wall 11 and the cell body 21, and there is a gap between the orthographic projection area S of the support member 3 on the first wall 11 and the center line 111. That is, the support member 3 is not disposed between the center of the cell 2 and the first wall 11, but rather there is a certain gap between the support member 3 and the center of the cell 2. By providing the support member 3, the cell 2 can be supported, thereby reducing the risk of lithium plating in the cell 2 due to uneven stress.

[0059] Please continue reading Figure 2The support member 3 includes a main support portion 31 and a thickened portion 32 connected to the main support portion 31. In the first direction X, the thickened portion 32 is located between the main support portion 31 and the electrode tab 22. In this embodiment, the thickness of the thickened portion 32 is greater than the thickness of the main support portion 31. By providing the main support portion 31, effective support can be achieved for the portion of the cell body 21 away from the electrode tab 22. By providing the thickened portion 32, the thickened portion 32 can be used to support the portion of the cell body 21 near the electrode tab 22. The thickened portion 32 is relatively thick, so that it can smoothly contact the portion of the cell body 21 near the electrode tab 22, forming effective support.

[0060] The battery cell provided in this embodiment has a casing 1 including a first wall 11 and a second wall 12. The area of ​​the first wall 11 is larger than the area of ​​the second wall 12, so that the first wall 11 can face the larger surface area of ​​the cell 2. A support member 3 is provided between the first wall 11 and the cell body 21, and there is a gap between the orthographic projection area S of the support member 3 on the first wall 11 and the center line 111 of the first wall 11. When the cell body 21 expands, the area of ​​the cell body 21 with a larger expansion amplitude directly contacts the first wall 11, while the area of ​​the cell body 21 with a smaller expansion amplitude contacts the support member 3. The main support part 31 contacts the electrode tab 22. Due to the pulling of the electrode tab 22, the area of ​​the cell body 21 with a smaller expansion range contacts the thickened part 32 of the support member 3. Since the support member 3 has a certain thickness, the pressure difference between the part of the cell 2 that contacts the first wall 11 and the part of the cell 2 that contacts the support member 3 is reduced, making the pressure distribution of the cell 2 more uniform, reducing the risk of stress concentration in the cell 2, thereby reducing the risk of lithium plating, improving the reliability of the battery cell under high power output and high impact environment, and thus improving the safety of the battery cell.

[0061] In at least one possible implementation, such as Figure 2As shown, the thickness of the thickened portion 32 in the first direction X is w, and the length of the tab 22 is L, where w = (1-1.5)L. The tab 22 exerts a certain pulling force on the electrode of the cell body 21, which can restrain the expansion of the electrode near the tab 22. However, the pulling force of the tab 22 on the electrode of the cell body 21 is within a certain range. That is, the portion of the electrode within a certain range from the tab 22 will be suppressed from expansion by the pulling force of the tab 22, while the portion of the electrode farther from the tab 22 will experience a smaller pulling force. Therefore, the size of the thickened portion 32 in the first direction X cannot be too large. If it is too large, it will exceed the restraining range of the tab 22, causing the electrode to press tightly against the thickened portion 32 when it expands, increasing the risk of electrode breakage. The size of the thickened portion 32 in the first direction X also cannot be too small. If it is too small, it will not be able to effectively support the electrode within the restraining range of the tab 22, and there will also be a problem of lithium plating due to uneven stress distribution. When the dimension of the thickened portion 32 in the first direction X and the length of the tab 22 satisfy the above relationship, the risk of the thickened portion 32 damaging the electrode sheet can be reduced. It can also work with the main support portion 31 to support the cell body 21, further reducing the risk of lithium plating and ensuring the safety and reliability of the battery cell.

[0062] For example, the value of w can be L, 1.1L, 1.2L, 1.3L, 1.4L, 1.5L, etc.

[0063] It should be noted that the length of the tab 22 can also be referred to as the height of the tab 22, specifically the dimension of the tab 22 in the first direction X. In this embodiment, the tab 22 has a portion connected to the cell body 21 and a portion extending beyond the cell body 21. In this embodiment, the length of the tab 22 specifically refers to the length of the portion of the tab 22 extending beyond the cell body 21.

[0064] In at least one possible implementation, such as Figure 3 As shown, the thickness of the main support portion 31 is T1, and the thickness of the thickened portion 32 is T2. T1 and T2 satisfy the relationship: T1 < T2 ≤ 1.5T1. Since the pulling force of the tab 22 on the electrode sheet of the cell body 21 is limited, the difference between the expansion amplitude of the portion of the electrode sheet near the tab 22 and the expansion amplitude of the portion far from the tab 22 will not be particularly large. Therefore, the difference between the thickness of the main support portion 31 and the thickness of the thickened portion 32 will not be particularly large. When the thickness of the main support portion 31 and the thickness of the thickened portion 32 satisfy the above relationship, on the one hand, it can accommodate the uneven expansion amplitude of the electrode sheet; on the other hand, it can better support the cell body 21, making the stress on each area of ​​the cell body 21 more uniform and reducing the risk of lithium plating; in addition, the thickened portion 32 will not damage the cell body 21 due to excessive thickness, thus extending the service life of the battery cell.

[0065] For example, the relationship between T2 and T1 can be T2 = 1.1T1, T2 = 1.2T1, T2 = 1.3T1, T2 = 1.4T1, T2 = 1.5T1, etc.

[0066] Optionally, the main support portion 31 can be a structure of uniform thickness, that is, the dimensions of the main support portion 31 are equal everywhere in the second direction Y.

[0067] It is understandable that the main support portion 31 can also be a structure of unequal thickness, as in some optional embodiments, such as... Figure 5 As shown, along the direction from the center line 111 to the support member 3, the size of the main support portion 31 gradually increases in the second direction Y. That is, the closer to the center line 111, the smaller the thickness of the main support portion 31. The thickness of the portion of the main support portion 31 away from the center line 111 is greater than the thickness of the portion closer to the center line 111, so that the change of the main support portion 31 matches the expansion range of the cell body 21. Consequently, the pressure on the areas of the cell body 21 with larger expansion range and the areas with smaller expansion range is approximately the same, further reducing the risk of stress concentration in the cell body 21, thereby reducing the risk of lithium plating, improving the reliability of the battery cell under high power output and high impact environments, and thus improving the safety of the battery cell.

[0068] In some alternative embodiments, such as Figure 3 As shown, the thickened portion 32 can be a structure of uniform thickness, that is, the size of the thickened portion 32 is equal everywhere in the second direction Y.

[0069] In other embodiments, the thickened portion 32 can also be a variable thickness structure, that is, the dimensions of the thickened portion 32 in the second direction Y can be unequal, with thin and thick regions. In some optional embodiments, the dimensions of the thickened portion 32 gradually increase in the second direction Y along the direction from the center line 111 to the support member 3, that is, the closer to the center line 111, the smaller the thickness of the thickened portion 32.

[0070] In at least one embodiment, when the thickened portion 32 is a variable thickness structure, the maximum dimension of the thickened portion 32 in the second direction Y is greater than the maximum dimension of the main support portion 31 in the second direction Y. That is, the maximum thickness of the thickened portion 32 is greater than the maximum thickness of the main support portion 31. With this configuration, the situation where the thickened portion 32 cannot contact the battery cell body 21 due to the support of the main support portion 31 on the battery cell body 21 can be avoided. This ensures that the thickened portion 32 can better support the area of ​​the battery cell body 21 that is bound by the tab 22, and the main support portion 31 will not damage the battery cell body 21.

[0071] Optionally, the maximum dimension of the thickened portion 32 in the second direction Y is less than or equal to 1.5 times the maximum dimension of the main support portion 31 in the second direction Y.

[0072] In some optional embodiments, when the thickened portion 32 is a variable thickness structure, the minimum dimension of the thickened portion 32 in the second direction Y is greater than the minimum dimension of the main support portion 31 in the second direction Y. That is, the minimum thickness of the thickened portion 32 is greater than the minimum thickness of the main support portion 31. With this configuration, the minimum thickness of the thickened portion 32 can still make contact with the cell body 21, thereby better supporting the cell body 21, ensuring a more uniform internal pressure distribution within the cell body 21, and reducing lithium plating.

[0073] Optionally, the minimum dimension of the thickened portion 32 in the second direction Y is less than or equal to 1.5 times the minimum dimension of the main support portion 31 in the second direction Y.

[0074] In at least one alternative embodiment, the main support portion 31 and the thickened portion 32 are integrally formed as a single structure. This configuration allows the main support portion 31 and the thickened portion 32 to have high overall integrity, facilitating the processing and manufacturing of the support member 3.

[0075] It is understandable that the main support part 31 and the thickened part 32 can also be a separate structure, and this embodiment does not limit this.

[0076] To prevent the support member 3 from damaging the battery cell body 21, in some optional embodiments, the support member 3 is made of an elastic material, such as silicone or rubber. It is understood that the support member 3 can also be made of a plastic material, such as plastic. It is also understood that the support member 3 is formed by a rigid outer elastic structure; this embodiment does not limit this.

[0077] Optionally, such as Figure 6 As shown, the maximum dimension of the projection area S of the support member 3 on the first wall 11 in the third direction Z is e, and the dimension of the shell 1 in the third direction Z is b, that is, the length of the shell 1 is b. Here, e and b satisfy the relationship: 10%b≤e≤25%b. The third direction Z is the length direction of the first wall 11, meaning that the dimension of the support member 3 in the third direction Z occupies 10%-25% of the length of the shell 1. This arrangement ensures that the dimension of the support member 3 in the third direction Z can better support the portion of the cell body 21 with a smaller expansion amplitude, and the dimension of the support member 3 is not too large, so as not to affect the direct contact between the portion of the cell body 21 with a larger expansion amplitude and the first wall 11. Furthermore, the dimension of the support member 3 is not too large, ensuring that its weight is not excessive. This balances the uniformity of force on the cell body 21 while meeting the lightweight requirements of the battery cell.

[0078] It should be noted that the maximum dimension e of the orthographic projection area S of the support member 3 on the first wall 11 in the third direction Z cannot be too large. If it is too large, the support member 3 will be wider, extending into the central area of ​​the cell body 21 (i.e., the area where the cell body 21 expands significantly). This will increase the pressure on the central area of ​​the cell body 21, leading to stress concentration and a higher risk of lithium plating. Furthermore, a wider support member 3 will result in a heavier battery cell. Conversely, the maximum dimension e of the orthographic projection area S of the support member 3 on the first wall 11 in the third direction Z cannot be too small. If it is too small, the contact area between the support member 3 and the cell body 21 will be smaller, increasing the pressure exerted by the support member 3 on the cell body 21. This will increase the risk of lithium plating due to stress concentration and will also affect the support effect on the cell body 21, thus impacting the voltage equalization effect.

[0079] For example, the relationship between e and b can be: e = 10%b, e = 12%b, e = 15%b, e = 18%b, e = 20%b, e = 22%b, e = 25%b, etc. This embodiment does not limit this.

[0080] In some alternative embodiments, please continue to refer to Figure 6 The maximum dimension of the orthographic projection area S of the support member 3 on the first wall 11 in the first direction X is h1, and the dimension of the shell 1 in the first direction X is h2. h1 and h2 satisfy the relationship: 50%h2≤h1≤h2. The first direction X is the height direction of the shell 1, meaning that the height of the support member 3 occupies 50%-100% of the height of the shell 1. This arrangement allows the support member 3 to better support the portion of the battery cell body 21 with a smaller expansion amplitude in the height direction of the shell 1. This ensures that more than half of the portion of the battery cell body 21 with a smaller expansion amplitude in the height direction of the shell 1 can be supported by the support member 3, thereby improving the support effect on the battery cell body 21. It also reduces the risk of lithium plating caused by concentrated pressure from the support member 3 in the area of ​​the battery cell body 21 with a smaller expansion amplitude, and improves the uniformity of the force on the battery cell body 21.

[0081] It should be noted that the maximum size of the orthographic projection area S of the support member 3 on the first wall 11 in the first direction X cannot be too small. If it is too small, it will cause uneven force on the cell body 21 in the height direction of the housing 1, which will result in poor support effect of the support member 3 on the cell body 21, and the cell body 21 will still have the risk of lithium plating. Of course, it is understandable that the support member 3 cannot exceed the top of the housing 1, otherwise it will affect the connection between the housing 1 and the cover plate.

[0082] For example, the relationship between h1 and h2 is: h1 = 50%h2, h1 = 60%h2, h1 = 70%h2, h1 = 80%h2, h1 = 90%h2, h1 = 100%h2. This embodiment does not limit this.

[0083] Optionally, such as Figure 6 As shown, the minimum distance between the orthographic projection area S of the support member 3 on the first wall 11 and the center line 111 is L, and the dimension of the housing 1 in the third direction Z is b. L and b satisfy the relationship: L = (3% - 49%)b. The minimum distance between the orthographic projection area S of the support member 3 on the first wall 11 and the center line 111 is the minimum distance from any point on the orthographic projection area S of the support member 3 on the first wall 11 to the center line 111 along the third direction Z. A larger value of L indicates that the support member 3 is farther from the center line 111, and a smaller value of L indicates that the support member 3 is closer to the center line 111. Since the support member 3 needs to contact the area of ​​the battery cell body 21 with a smaller expansion amplitude, and this area is some distance from the center area of ​​the battery cell body 21, the value of L cannot be too small. However, the support member 3 cannot extend beyond the housing 1 in the third direction Z, therefore, the value of L cannot be too large either.

[0084] In some optional embodiments, L = (25%-40%)b. When the value of L is within this range, the distance between the support member 3 and the center line 111 is neither too large nor too small, and the support member 3 can contact the area of ​​the cell body 21 with a small expansion amplitude, thereby supporting the cell body 21. The support member 3 will not contact the area of ​​the cell body 21 with a large expansion amplitude, reducing the risk of lithium plating in the cell body 21 due to uneven force, extending the service life of the cell body 21, and improving the reliability of the cell body 21 and the battery cell.

[0085] For example, the relationship between L and b is: L = 3%b, L = 5%b, L = 10%b, L = 15%b, L = 25%b, L = 28%b, L = 30%b, L = 35%b, L = 40%b, L = 45%b, L = 49%b, etc.

[0086] Optionally, in one embodiment, such as Figure 6As shown, the minimum distance between the orthographic projection area S of the support member 3 on the first wall 11 and the second wall 12 is d, and the dimension of the housing 1 in the third direction Z is b. d and b satisfy the relationship: d = (8% - 12%)b. The minimum distance between the orthographic projection area S of the support member 3 on the first wall 11 and the second wall 12 is the minimum value among the distances from any point on the orthographic projection area S of the support member 3 on the first wall 11 to the plane containing the second wall 12 along the third direction Z. By controlling the relationship between the distance between the support member 3 and the second wall 12 and the length of the housing 1, the support member 3 is not too close to the second wall 12, and the distance between them is not too large. If the support member 3 is too close to the second wall 12, the improvement in the support effect of the cell body 21 is limited, and it will also result in a larger width and weight of the support member 3, which is not conducive to the lightweighting of the battery cell. If the support member 3 is too far from the second wall 12, the edge area of ​​the cell body 21 near the second wall 12 will not be supported, which will lead to lithium plating due to excessive stress, resulting in lower safety of the battery cell.

[0087] For example, the relationship between d and b can be: d = 8%b, d = 9%b, d = 10%b, d = 11%b, d = 12%b, etc.

[0088] In some other optional embodiments, the minimum distance d between the orthographic projection area S of the support member 3 on the first wall 11 and the second wall 12 ranges from 5mm to 20mm. For example, the minimum distance d between the orthographic projection area S of the support member 3 on the first wall 11 and the second wall 12 can be 5mm, 10mm, 15mm, 18mm, 20mm, etc.

[0089] In some alternative embodiments, please continue to refer to Figure 6 The minimum distance between the orthographic projection area S of the support member 3 on the first wall 11 and the edge of the top of the housing 1 is h3, and the dimension of the housing 1 in the first direction X is h2. h3 and h2 satisfy the relationship: h3 = (20% - 60%)h2. The minimum distance between the orthographic projection area S of the support member 3 on the first wall 11 and the edge of the top of the housing 1 is the minimum value among the distances from any point on the orthographic projection area S of the support member 3 on the first wall 11 to the top of the housing 1 along the first direction X. When h3 and h2 satisfy this relationship, the distance between the support member 3 and the top of the housing 1 is more suitable, which can better support the cell body 21 without affecting the electrical connection between the cell body 21 and the cover assembly of the battery cell, and without affecting the assembly of the housing 1 and the cover assembly.

[0090] Optionally, the minimum distance h3 between the orthographic projection area S of the support member 3 on the first wall 11 and the edge of the top of the housing 1 ranges from 8mm to 150mm. For example, the minimum distance h3 between the orthographic projection area S of the support member 3 on the first wall 11 and the edge of the top of the housing 1 can be 8mm, 10mm, 20mm, 30mm, 50mm, 60mm, 80mm, 100mm, 120mm, or 150mm.

[0091] Optionally, the support member 3 can be disposed on the housing 1; or, the support member 3 can also be disposed on the cell body 21, which is not limited in this embodiment.

[0092] In one embodiment, the support member 3 is disposed on the housing 1, and the support member 3 and the first wall 11 of the housing 1 are separate structures. Understandably, the separate structure can be: as follows: Figure 3 As shown, the support member 3 is connected to the first wall 11. The connection method can be bonding, welding, or other methods. This arrangement allows for flexible connection of the support member 3 to the first wall 11 according to the position where the battery cell body 21 needs support. When the support member 3 is connected to the housing 1, the connection between the support member 3 and the housing 1 uses an arc transition to reduce stress. Alternatively, in a split structure, the support member 3 and the first wall 11 can be unconnected. For example, the support member 3 can be connected to the insulating film covering the battery cell body 21 without being connected to the first wall 11.

[0093] In other embodiments, the support member 3 is disposed on the housing 1, and the support member 3 and the first wall 11 are integrally formed. This arrangement improves the overall integrity of the support member 3 and the housing 1, reduces the risk of separation between the support member 3 and the housing 1, and allows the support member 3 to better support areas of the battery cell body 21 with smaller expansion amplitudes.

[0094] In one possible implementation, the battery cell 2 further includes an insulating film (not shown) covering the battery cell body 21. A support member 3 may be disposed on the insulating film. The insulating film serves to prevent short circuits between the battery cell body 21 and the housing 1.

[0095] In one embodiment, the support member 3 and the insulating film are independent of each other, and the support member 3 is connected to the insulating film. This facilitates the design of the position of the support member 3 relative to the insulating film, making the position of the support member 3 on the insulating film more flexible.

[0096] In other embodiments, the support member 3 and the insulating film are integrally formed, that is, the material of the support member 3 is the same as that of the insulating film, which improves the integrity of the support member 3 and the insulating film; and the number of parts can be reduced, which facilitates the assembly of battery cells and improves assembly efficiency.

[0097] If the surface of the support member 3 facing the cell body 21 has sharp corners, it will increase the risk of damaging the cell body 21. In one possible implementation, such as Figure 6 or Figure 7 As shown, the surface of the support member 3 facing the cell body 21 is curved. This design ensures that the surface of the support member 3 in contact with the cell body 21 is curved, without sharp corners, thereby avoiding the risk of puncturing or scratching the cell body 21 and reducing the impact of the support member 3 on the service life of the cell body 21.

[0098] Optionally, based on the fact that the surface of the support member 3 facing the cell body 21 is an arc surface, the shape of the support member 3 can have various forms, for example, in Figure 7 In the middle, support member 3 can be hemispherical; for example, such as Figure 8 As shown, the support member 3 can also be elongated. The specific shape of the support member 3 can be selected according to requirements, and this embodiment does not limit it.

[0099] It is understandable that the surface of the support member 3 facing the cell body 21 can also be a plane, an inclined plane, or a wavy surface, etc., and this embodiment does not limit this. For example, Figure 9 As shown, the surface of the support member 3 facing the cell body 21 is a plane. For example, as... Figure 10 As shown, the surface of the support member 3 facing the cell body 21 is inclined.

[0100] It is understandable that the surface of the support member 3 facing the cell body 21 can also be composed of at least two combinations of a plane, an inclined plane, an arc surface, and a wavy surface. For example, as Figure 9 As shown, the surface of the support member 3 facing the cell body 21 consists of two arc surfaces and a plane (for example, a plane cut on a semi-cylindrical structure). The plane can increase the contact area between the support member 3 and the cell body 21 to ensure the uniformity of force on the cell body 21. The arc surfaces can reduce the risk of the support member 3 damaging the cell body 21 and improve reliability.

[0101] Optionally, in one embodiment, such as Figure 9 As shown, the support member 3 is a strip-shaped structure, and the strip-shaped support member 3 can extend along the first direction X. In other embodiments, such as Figure 10 As shown, the support member 3 is a plate-shaped structure. The length direction of the support member 3 can be the first direction X, the width direction of the support member 3 can be the third direction Z, and the thickness direction of the support member 3 can be the second direction Y.

[0102] Optionally, the shell 1 is typically rectangular, in which case, such as Figure 1 As shown, there are two first walls 11, which are arranged opposite to each other in the second direction Y, and, as... Figure 7As shown, the distance between the two opposing surfaces of the two first walls 11 is n. It should be noted that n is related to the thickness of the shell 1 and the wall thickness of the shell 1.

[0103] In this embodiment, the maximum dimension of the support member 3 in the second direction Y is x1, and satisfies: x1 ≤ 5%n. When x1 is within this range, the support member 3 can better support the cell body 21, making the force on each area of ​​the cell body 21 more uniform and reducing the risk of lithium plating. Of course, it is understood that x1 is not 0.

[0104] For example, the relationship between x1 and n can be: x1 = 1%n, x1 = 2%n, x1 = 3%n, x1 = 4%n, x1 = 5%n.

[0105] For example, the minimum dimension of the support member 3 in the second direction Y is x2, and satisfies: 0 < x2 ≤ 2.5%n. When x2 is within this range, the support effect of the support member 3 on the battery cell body 21 can be improved, reducing the risk that the battery cell body 21 cannot contact the support member 3 after expansion, so as to ensure that the force on each area of ​​the battery cell body 21 is more uniform and to prevent stress concentration in the battery cell body 21.

[0106] For example, the relationship between x2 and n can be: x2 = 1%n, x2 = 1.2%n, x2 = 1.5%n, x2 = 2%n, x2 = 2.5%n.

[0107] In some alternative embodiments, such as Figure 6 As shown, a support member 3 is provided on one side of the centerline 111 in the Z-direction. In other alternative embodiments, such as Figures 8 to 10 As shown, the center line 111 is provided with support members 3 on both sides of the third direction Z, so as to support the two areas of the cell body 21 with small expansion amplitude in the third direction Z, thereby improving the uniformity of force on the entire cell body 21.

[0108] In one embodiment, such as Figure 7 As shown, a support member 3 is provided on one side of the cell body 21 in the thickness direction (i.e., the second direction Y). In other embodiments, support members 3 are provided on both sides of the cell body 21 in the thickness direction to support both sides of the cell body 21 in the thickness direction, further improving the support effect on the entire cell body 21, so that both sides of the cell body 21 in the thickness direction can be subjected to uniform force, reducing the risk of lithium plating.

[0109] The battery cell provided in this embodiment optimizes the mechanical structure of the casing 1 and sets a support member 3 between the first wall 11 and the cell body 21. This effectively enables the battery cell to uniformly bear the expansion force of the cell body 21 during charging and discharging, making the internal pressure distribution of the battery more uniform. This reduces internal stress concentration, lowers the risk of lithium plating, and improves the reliability of the battery under high power output and high impact environments. It is suitable for various battery types, especially for use in high energy density batteries and high power batteries, and has high safety and long service life.

[0110] This embodiment provides a battery that can reduce the risk of lithium plating and has high reliability and safety.

[0111] The battery includes the aforementioned battery cells. In this embodiment, the battery can be an electrode cell, a cylindrical cell, a wound cell, etc., and this embodiment is not limited to these.

[0112] This embodiment also provides an electrical device with high reliability and safety.

[0113] The electrical equipment includes the aforementioned battery cells; or, the electrical equipment includes the aforementioned batteries.

[0114] For example, electrical equipment includes, but is not limited to: mobile phones, portable devices, laptops, electric vehicles, electric cars, ships, spacecraft, electric toys, and power tools, etc. For example, spacecraft include airplanes, rockets, space shuttles, and spacecraft, etc. Electric toys include stationary or mobile electric toys, such as game consoles, electric vehicle toys, electric ship toys, and electric airplane toys, etc. Power tools include metal cutting power tools, grinding power tools, assembly power tools, and railway power tools, such as electric drills, electric grinders, electric wrenches, electric screwdrivers, electric hammers, impact drills, concrete vibrators, and electric planers.

[0115] Note that the above description is merely a preferred embodiment of the present invention and the technical principles employed. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and various obvious changes, readjustments, and substitutions can be made without departing from the scope of protection of the present invention. Therefore, although the present invention has been described in detail through the above embodiments, the present invention is not limited to the above embodiments, and may include many other equivalent embodiments without departing from the concept of the present invention. The scope of the present invention is determined by the scope of the appended claims.

Claims

1. A single battery cell, characterized in that, include: The shell (1) includes a first wall (11) and a second wall (12) connected to each other, the area of ​​the first wall (11) is larger than the area of ​​the second wall (12), and the first wall (11) has a centerline extending along a first direction (X), the first direction (X) being the height direction of the first wall (11); The battery cell (2) includes a battery cell body (21) disposed in the housing (1), and the battery cell body (21) is connected to a tab (22); A support member (3) is disposed between the first wall (11) and the battery cell body (21). The support member (3) has a gap between its orthographic projection area (S) on the first wall (11) and the center line. The support member (3) includes a main support part (31) and a thickened part (32) connected to the main support part (31). In the first direction (X), the thickened part (32) is located between the main support part (31) and the tab (22). The thickness of the thickened part (32) is greater than the thickness of the main support part (31).

2. The battery cell according to claim 1, characterized in that, The thickened portion (32) has a dimension w in the first direction (X), and the tab (22) has a length L, where w = (1-1.5)L.

3. The battery cell according to claim 1, characterized in that: The thickness of the main support part (31) is T1, and the thickness of the thickened part (32) is T2, satisfying the relationship: T1<T2≤1.5T1.

4. The battery cell according to claim 1, characterized in that: Along the center line pointing towards the support member (3), the size of the main support part (31) gradually increases in the second direction (Y), wherein the second direction (Y) is the thickness direction of the first wall (11).

5. The battery cell according to claim 1, characterized in that: The maximum dimension of the thickened portion (32) in the second direction (Y) is greater than the maximum dimension of the main support portion (31) in the second direction (Y); And / or, the minimum dimension of the thickened portion (32) in the second direction (Y) is greater than the minimum dimension of the main support portion (31) in the second direction (Y); Wherein, the second direction (Y) is the thickness direction of the first wall (11).

6. The battery cell according to any one of claims 1-5, characterized in that, The main support (31) and the thickened part (32) are an integral structure.

7. The battery cell according to any one of claims 1-5, characterized in that: The maximum dimension of the orthographic projection area (S) of the support member (3) on the first wall (11) in the third direction (Z) is e, and the dimension of the shell (1) in the third direction (Z) is b, wherein e and b satisfy the relationship: 10%b≤e≤25%b; wherein the third direction (Z) is the width direction of the first wall (11); And / or, The maximum dimension of the orthographic projection area (S) of the support member (3) on the first wall (11) in the first direction (X) is h1, and the dimension of the shell (1) in the first direction (X) is h2, wherein h1 and h2 satisfy the relationship: 50%h2≤h1≤h2; And / or, The minimum distance between the orthographic projection area (S) of the support member (3) on the first wall (11) and the center line is L, and the size of the shell (1) in the third direction (Z) is b, wherein L and b satisfy the relationship: L = (3% - 49%)b.

8. The battery cell according to any one of claims 1-5, characterized in that: The minimum distance between the orthographic projection area (S) of the support member (3) on the first wall (11) and the second wall (12) is d, and the size of the shell (1) in the third direction (Z) is b. d and b satisfy the relationship: d = (8% - 12%)b; and / or, the value range of d is 5mm-20mm. And / or, The minimum distance between the orthographic projection area (S) of the support member (3) on the first wall (11) and the edge of the top of the shell (1) is h3, and the size of the shell (1) in the first direction (X) is h2. h3 and h2 satisfy the relationship: h3 = (20% - 60%)h2; and / or, the value of h3 is in the range of 8mm-150mm.

9. A battery, characterized in that, Includes the battery cell as described in any one of claims 1-8.

10. Electrical equipment, characterized in that, The electrical device includes a battery cell as described in any one of claims 1-8; or, the electrical device includes a battery as described in claim 9.

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