Battery pack and single battery thereof

Abstract

The utility model relates to the technical field of new energy batteries, and discloses a single battery and a battery pack, the single battery comprises: a shell having a first direction, one end of the shell along the first direction having an opening, the shell also having an accommodating cavity communicated with the opening; the top cover comprises a cover plate, a pole and a sealing element, the cover plate covers the opening and is connected with the shell, a through hole penetrating through the top cover in the first direction is formed in the cover plate, the pole penetrates through the through hole, the pole comprises a circumferential direction with the first direction as the axis, the pole is provided with a mounting groove formed in the circumferential direction, the sealing element is partially arranged in the mounting groove in a surrounding mode, and the sealing element is connected to the cover plate; in the first direction, the maximum size of the mounting groove is t mm, the maximum size of the sealing piece is h mm, and t-h is larger than-0.5 and smaller than 2. According to the single battery disclosed by the utility model, the sealing element can be kept in the mounting groove, so that the problems of falling, dislocation and the like are prevented, and the failure of a sealing function is prevented.

Description

Technical Field

[0001] The utility model relates to the technical field of new energy batteries, in particular to a single battery and a battery pack. Background Art

[0002] At present, in a single battery, a sealing ring is sleeved on a pole column, and the sealing ring fixes its position on the pole column by its own elasticity. However, during the transportation and assembly process of the pole column and the sealing ring, due to factors such as jolting and incorrect operation by workers, situations such as misalignment and detachment may occur, and the detachment and misalignment of the sealing ring cannot be prevented. Subsequently, the sealing function of the sealing ring in the top cover fails, affecting battery safety and causing potential risks such as liquid leakage and short circuit. Summary of the Utility Model

[0003] The purpose of the utility model is to provide a single battery and a battery pack with the single battery, which can limit the change of the position of the sealing ring itself and prevent the problems of detachment and misalignment of the sealing ring.

[0004] In order to achieve the above purpose, the utility model provides a single battery, including:

[0005] A housing having a first direction, one end of the housing along the first direction having an opening, and the housing further having a receiving cavity communicating with the opening;

[0006] A top cover including a cover plate, a pole column and a seal, the cover plate covering the opening and connected to the housing, the cover plate being provided with a through hole penetrating the top cover along the first direction, the pole column passing through the through hole, the pole column having a mounting groove provided along the circumferential direction of the pole column, and the seal being partially surrounded and disposed in the mounting groove;

[0007] In the first direction, the maximum dimension of the mounting groove is t mm, and the maximum dimension of the seal is h mm, satisfying: -0.5 < t - h < 2.

[0008] In some embodiments of the present application:

[0009] The pole column includes a pole column body, a base and a limiting portion, the cross-sectional area of the pole column body is smaller than the cross-sectional area of the limiting portion, the pole column body passes through the through hole, the base is disposed at one end of the pole column body facing the receiving cavity, the limiting portion is disposed around the outer peripheral surface of the pole column body, the limiting portion and the base are spaced apart in the first direction, and the base, the limiting portion and the pole column body between the limiting portion and the base jointly enclose the mounting groove.

[0010] In some embodiments of the present application:

[0011] In the first direction, the maximum dimension of the seal is h mm, satisfying: 0.1≤h≤3.

[0012] In some embodiments of the present application:

[0013] The mounting groove comprises a first surface, a second surface and a third surface, the first surface is parallel to the first direction, the second surface is inclined relative to the first surface, the second surface is arranged on a side of the first surface facing the accommodating cavity, the third surface is inclined relative to the first surface, and the third surface is arranged on a side of the first surface facing away from the accommodating cavity;

[0014] The shape of the portion of the sealing member located in the mounting groove is adapted to the shape of the mounting groove.

[0015] In some embodiments of the present application:

[0016] In a cross section of the installation groove along the first direction, an angle between the second surface and the third surface is α°, satisfying: 0°<α°≤160°.

[0017] In some embodiments of the present application:

[0018] The base also includes a base body and a step portion, the base body is arranged at one end of the pole body facing the accommodating cavity, the step portion is arranged on the base body and is located on a side of the base body facing the limiting portion, the step portion and the limiting portion are arranged at intervals, and the step portion, the limiting portion and the outer peripheral surface of the pole body between the step portion and the limiting portion jointly enclose the mounting groove.

[0019] In some embodiments of the present application:

[0020] In the first direction, the size of the mounting groove is t mm, satisfying: 0.4≤t≤2.

[0021] In some embodiments of the present application:

[0022] The pole has a radial direction perpendicular to the first direction, the size of the limiting portion in the radial direction is d1 mm, the size of the portion of the pole body located in the mounting groove in the radial direction is d2 mm, and the following is satisfied: 0.1≤d1-d2≤5.

[0023] In some embodiments of the present application:

[0024] The installation groove includes a first surface parallel to the first direction, and there is a gap between the first surface and the seal. The pole has a radial direction perpendicular to the first direction. In the radial direction, the size of the gap is g mm, satisfying 0 ≤ g ≤ 2.

[0025] This application also provides a battery pack, including:

[0026] A box body;

[0027] As described above, the single cells are arranged inside the box body and are electrically connected to each other.

[0028] The present utility model provides a single cell and a battery pack having the single cell. Compared with the prior art, its beneficial effects are as follows:

[0029] A single cell of the present utility model includes a housing and a top cover. The top cover includes a cover plate, a pole, and a seal. A circumferentially arranged installation groove is provided on the pole. A part of the seal is arranged around the installation groove. The seal is connected to the cover plate. In the first direction, the maximum size of the installation groove is t mm, and the maximum size of the seal is h mm, satisfying -0.5 < t - h < 2. With such a structure, the installation groove can keep the seal in the installation groove, thereby preventing problems such as falling off and dislocation, preventing the sealing function from failing, avoiding affecting the battery safety, and reducing potential risks such as liquid leakage and short circuit.

[0030] A battery pack of the present utility model includes the above single cell, which can keep the seal in the installation groove, thereby preventing problems such as falling off and dislocation, preventing the sealing function from failing, avoiding affecting the battery safety, and reducing potential risks such as liquid leakage and short circuit. Description of the Drawings

[0031] Figure 1 is an exploded view of the single cell according to an embodiment of the present utility model.

[0032] Figure 2 is a structural view of the top cover according to an embodiment of the present utility model.

[0033] Figure 3 is a structural view of the pole and the seal according to an embodiment of the present utility model.

[0034] Figure 4 is Figure 3 the disassembly view of

[0035] Figure 5 is Figure 3 a cross-sectional view along the first direction.

[0036] Figure 6 is Figure 5Enlarged view of location A.

[0037] Figure 7 It is a cross-sectional view of the terminal post of an embodiment of the present utility model along the first direction.

[0038] Figure 8 It is a cross-sectional view of the terminal post and the seal of another embodiment of the present utility model along the first direction.

[0039] Figure 9 It is Figure 8 Schematic structural view of the terminal post in

[0040] Figure 10 It is Figure 8 Cross-sectional view of the seal in along the first direction.

[0041] Figure 11 It is a cross-sectional view of the terminal post and the seal of another embodiment of the present utility model along the first direction.

[0042] Figure 12 It is Figure 11 Cross-sectional view of the terminal post in along the first direction.

[0043] Figure 13 It is Figure 11 Cross-sectional view of the seal in along the first direction.

[0044] Figure 14 It is a cross-sectional view of the top cover of an embodiment of the present utility model along the first direction.

[0045] Figure 15 It is Figure 14 Enlarged schematic view of location B.

[0046] In the figure, 1. top cover; 2. cover plate; 3. terminal post; 4. seal; 5. housing; 6. battery cell; 21. through hole; 31. terminal post body; 32. base; 33. limiting part; 34. mounting groove; 321. base body; 322. step part; 341. first surface; 342. second surface; 343. third surface;

[0047] Z. first direction; A. radial direction. Detailed implementation manners

[0048] The following combines the drawings and embodiments to further describe in detail the specific implementation manners of the present utility model. The following embodiments are used to illustrate the present utility model, but do not limit the scope of the present utility model.

[0049] In the description of the present utility model, it should be noted that the orientation or positional relationship indicated by the terms "center", "longitudinal", "lateral", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present utility model. In addition, the terms "first", "second", "third" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance.

[0050] In the description of the present utility model, it should be noted that unless otherwise clearly specified and defined, the terms "installation", "connection", "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 directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood according to specific situations.

[0051] In addition, in the description of the present utility model, unless otherwise specified, the meaning of "a plurality" is two or more.

[0052] For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood according to specific situations.

[0053] Please refer to Figures 1 - 5 , a single cell of a preferred embodiment of the present utility model embodiment includes: a housing 5 and a top cover 1.

[0054] The housing has a first direction Z. One end of the housing along the first direction Z has an opening, and the housing also has a receiving cavity communicating with the opening.

[0055] Since the single cell of this embodiment is a rectangular body, the housing is also a rectangular body.

[0056] The receiving cavity is used to place the battery core 6, and the opening is used for the battery core to pass through so that the battery core can be loaded into the receiving cavity.

[0057] In other embodiments, the housing can also be set as a square body or a cylinder, and in specific implementations, it can be set according to needs.

[0058] In this embodiment, the height direction of the housing is the first direction Z, the length direction of the housing 1 is the second direction, and the width direction of the housing is the third direction. The first direction Z, the second direction, and the third direction are perpendicular to each other. Perpendicular means a state where the angle is 85° - 95°.

[0059] The top cover 1 includes a cover plate 2, a terminal post 3, and a seal 4. The cover plate 2 is disposed at the opening and connected to the housing. The cover plate 2 is provided with a through hole 21 penetrating the cover plate 2 along the first direction Z. The terminal post 3 passes through the through hole 21. The terminal post 3 includes a circumferential direction with the first direction Z as the axis. The terminal post 3 has an installation groove 34 arranged circumferentially, and the seal 4 is partially arranged around the installation groove.

[0060] In the first direction Z, the maximum dimension of the installation groove 34 is t mm, and the maximum dimension of the seal 4 is h mm, satisfying: -0.5 < t - h < 2.

[0061] It should be noted that the maximum dimension of the installation groove 34 in the first direction refers to the height of the installation groove 34, and the maximum dimension of the seal 4 in the first direction refers to the thickness of the seal 4. Both can be measured by a vernier caliper.

[0062] It should be noted that the value of t - h is within the range of (-0.5, 2). The specific value of t - h can be any value such as 0, 0.4, -0.3, -0.2, -0.1, 0, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9 or the range value between any two values.

[0063] In some embodiments, the seal 4 can be installed in an interference fit with the installation groove 34. When the seal 4 is installed in an interference fit with the installation groove 34, the thickness of the seal 4 is greater than or equal to the height of the installation groove 34. At this time, t - h is negative or zero. It is necessary to control that the thickness of the seal 4 is greater than the height of the installation groove 34 by less than 0.5 mm to avoid the seal 4 breaking when the seal 4 is installed too thickly into the installation groove 34, resulting in seal failure. Therefore, it is necessary to control -0.5 < t - h ≤ 0.

[0064] In some embodiments, the seal 4 can also be assembled with a clearance in the installation groove 34. When the seal 4 is assembled with a clearance in the installation groove 34, the thickness of the seal 4 is less than the height of the installation groove 34. At this time, t - h is positive. It is necessary to control that the thickness of the seal 4 is less than the height of the installation groove 34 by less than 2 mm to avoid too large a clearance, resulting in the seal 4 arranged in the installation groove 34 being skewed, resulting in seal failure.

[0065] Since the housing of this embodiment is a rectangular body, the opening is configured as a rectangular opening to match the shape of the housing, and the shape of the top cover 1 matches the opening. Specifically, the cover plate 2 is in the shape of a rectangular sheet.

[0066] The pole 3 is used to electrically connect the single cell to external equipment. The pole 3 is divided into a positive pole and a negative pole with different polarities. Each single cell can have multiple positive poles or negative poles. In this embodiment, two poles 3, one negative and one positive, are provided. The two poles 3 are arranged along the second direction, and both poles 3 are electrically connected to the battery cell in the accommodating cavity. In specific production implementation, the number and position of the electrode poles can be set as needed.

[0067] The pole 3 is made of aluminum or copper, has conductive properties, is resistant to electrolyte corrosion, and is resistant to high and low temperatures. It can work normally in a temperature range of -40°C to 300°C, has a tensile strength of 90MPa to 260MPa, and a Vickers hardness of 20 to 90.

[0068] The number of seals 4 corresponds to the number of poles 3. When the seals 4 are sleeved on the poles 3, they also abut against the cover plate 2 and seal the gap between the poles 3 and the through holes 21 to prevent risks such as leakage and short circuit.

[0069] The sealing ring is made of fluororubber, the fluorine content of fluororubber is greater than 50%, the Shore hardness is 50-90, it is resistant to strong acids and alkalis, electrolytes, and high temperatures of 300°C, and its compression is 20% to 70%, and its insulation resistance is greater than 200Mohm.

[0070] This embodiment provides a single cell battery and sets a mounting groove 34 on the pole 3. The mounting groove 34 can keep the seal 4 in the mounting groove 34, thereby preventing the problem of falling off and dislocation, preventing the sealing function from failing, avoiding affecting the battery safety, and reducing the potential risks of leakage, short circuit, etc.

[0071] In some embodiments, the mounting groove 34 includes a groove wall, the groove wall includes a first surface 341, a second surface 342 and a third surface 343, the axis of the first surface 341 is parallel to the first direction Z, the second surface 342 is inclined relative to the first surface 341, the second surface 342 is arranged on the side of the first surface 341 facing the accommodating cavity, the third surface 343 is inclined relative to the first surface 341, and the third surface 343 is arranged on the side of the first surface 341 away from the accommodating cavity.

[0072] The cross-sectional shape of the mounting groove 34 along the first direction Z is a trapezoid, and the shape of the portion of the sealing member 4 located in the mounting groove 34 matches the shape of the mounting groove 34 .

[0073] The shapes of the mounting groove 34 and the sealing member 4 are adapted to each other, so as to achieve the effect of limiting the position of the sealing member 4 .

[0074] In a cross section of the mounting groove 34 along the first direction Z, an angle between the second surface 342 and the third surface 343 is α°, satisfying: 0°<α°≤160°.

[0075] Since both the second surface 342 and the third surface 343 are inclined and need to be processed later. If the value of α is too large, it will affect the limiting effect on the seal 4; if the value of α is too small, the processing difficulty is relatively large and it is difficult to implement. Therefore, when 0° < α° ≤ 160°, it can not only limit the position of the seal 4 but also facilitate implementation.

[0076] When measuring α, a common length measuring tool can be used, such as a protractor. For the two straight lines formed by the second surface 342 and the third surface 343 respectively in the first direction Z as the angles, measure the angle formed by these two straight lines with a protractor, measure multiple times and take the average value to obtain the included angle α° between the second surface 342 and the third surface 343.

[0077] In some embodiments, the pole 3 includes a pole body 31, a base 32 and a limiting portion 33. The cross-sectional area of the pole body 31 is smaller than that of the limiting portion 33. The pole body 31 passes through the through hole 21. The base 32 is arranged at one end of the pole body 31 facing the accommodation cavity. The limiting portion 33 is arranged around the outer peripheral surface of the pole body 31. The limiting portion 33 and the base 32 are arranged at intervals in the first direction Z. The base 32, the limiting portion 33 and the pole body 31 between the limiting portion 33 and the base 32 together enclose an installation groove 34.

[0078] Both ends of the pole body 31 are located on both sides of the cover plate 2 along the first direction Z, so that one end of the pole 3 can be used to connect the battery cell in the accommodation cavity and the other end can be used to electrically connect with external equipment. The outer diameter of the base 32 is larger and larger than the outer diameter of the through hole 21. After the single battery is assembled, it can limit the pole 3 from disengaging from the cover plate 2.

[0079] Please refer to Figure 6 、 Figures 14 - 15 , a part of the seal 4 is located in the installation groove 34 to limit the position of the seal 4 relative to the pole body 31 from changing, and another part of the seal 4 can abut against the cover plate 2 to realize the sealing function of the seal 4.

[0080] Specifically, the limiting portion 33 can limit the movement of the seal 4 in the direction of the cover plate 2 along the first direction Z, and the base 32 can limit the movement of the seal 4 in the direction away from the cover plate 2 along the first direction Z.

[0081] In some embodiments, in the first direction Z, the maximum dimension of the seal 4 is h mm, satisfying: 0.1 ≤ h ≤ 3.

[0082] The value of h is matched with the value of the installation groove 31.

[0083] Since there is also a rotation prevention structure provided on the terminal post body 31 to prevent the rotation of the terminal post 3 on the cover plate 2, in this embodiment, the rotation prevention structure is provided on the side of the limiting portion 33 away from the installation groove 34.

[0084] If the size of the seal 4 in the first direction Z is too small, there will be problems such as difficult processing and poor sealing effect. If the size of the seal 4 in the first direction Z is too large, it will affect the size of the rotation prevention structure, resulting in a poor rotation prevention effect. Therefore, within the range of 0.1 ≤ h ≤ 3, while ensuring the sealing effect, it will not affect the rotation prevention structure and is also conducive to processing operations.

[0085] When measuring h, a common length measuring tool can be used, such as a ruler or a tape measure.

[0086] Specifically, when measuring h, taking one end face of the seal 4 in the first direction Z as the reference plane, measure the distance between the other end face of the seal 4 and the reference plane along the first direction Z through the length measuring tool, measure multiple times and take the average value, and the maximum size of the seal 4 is h mm.

[0087] In some embodiments, please refer to Figures 11 - 13 , the base 32 further includes a base body 321 and a stepped portion 322. The base body 321 is disposed at one end of the terminal post body 31 facing the accommodating cavity. The stepped portion 322 is disposed on the base body 321 and is located on the side of the base body 321 facing the limiting portion 33. The stepped portion 322 and the limiting portion 33 are spaced apart. The outer peripheral surface of the terminal post body 31 between the stepped portion 322, the limiting portion 33, and the stepped portion 322 and the limiting portion 33 together enclose to form the installation groove 34.

[0088] Please refer to Figures 11 - 13 , the stepped portion 322 and the limiting portion 33 jointly limit the movement of the seal 4. Specifically, the limiting portion 33 can limit the movement of the seal 4 in the direction of the cover plate 2 along the first direction Z, and the stepped portion 322 can limit the movement of the seal 4 in the direction away from the cover plate 2 along the first direction Z.

[0089] In some embodiments, in the first direction Z, the size of the installation groove 34 is t mm, satisfying: 0.4 ≤ t ≤ 2.

[0090] Since the installation groove 34 is provided on the basis of the stepped portion 322, on the one hand, the processing problems of the stepped portion 322 and the limiting portion 33 need to be considered, and on the other hand, the material usage of the entire terminal post body 31 needs to be considered. If the value of t is too small, there will be problems such as difficult processing of the stepped portion 322 and the limiting portion 33. If the value of t is too large, on the premise of ensuring the function of the rotation prevention structure, there will be too much material usage and waste of materials.

[0091] When measuring t, a common length measuring tool can be used, such as a ruler or a tape measure.

[0092] Specifically, when measuring t, the surface of the step portion 322 facing the limiting portion 33 in the first direction Z is used as the reference surface, and the distance between the reference surface and the surface of the limiting portion 33 facing the step portion 322 in the first direction Z is measured along the first direction Z by a length measuring tool. Or, the surface of the limiting portion 33 facing the step portion 322 in the first direction Z is used as the reference surface, and the distance between the reference surface and the surface of the step portion 322 facing the limiting portion 33 in the first direction Z is measured along the first direction Z by a length measuring tool. Measure multiple times and take the average value to obtain the maximum size of the installation groove 34 as t mm.

[0093] In some embodiments, the pole 3 has a radial direction A perpendicular to the first direction Z. The dimension of the limiting portion 33 in the radial direction A is d1 mm, and the dimension of the portion of the pole body 31 located at the installation groove 34 in the radial direction A is d2 mm, satisfying: 0.1 ≤ d1 - d2 ≤ 5.

[0094] The difference between d1 and d2 means the size of the outer diameter of the limiting portion 33. If the value is too small, the contact area between the limiting portion 33 and the seal 4 will be too small, and there is a risk that the seal 4 will come out of the installation groove 34; if the value is too large, there will be a problem of material waste in the overall pole body 31. Satisfying 0.1 ≤ d1 - d2 ≤ 5 can save the material of the overall pole body 31 while ensuring the limiting effect of the limiting portion 33 on the seal 4.

[0095] When measuring d1 and d2, a common length measuring tool can be used, such as a ruler or a tape measure.

[0096] When measuring d1, in the radial direction A, take the two points on the limiting portion 33 that are farthest apart, and measure the distance between these two points by a length measuring tool. Measure multiple times and take the average value to obtain the dimension of the limiting portion 33 in the radial direction A as d1 mm.

[0097] When measuring d2, in the radial direction A, take the two points on the pole body 31 between the limiting portion 33 and the base 32 that are farthest apart, and measure the distance between these two points by a length measuring tool. Measure multiple times and take the average value. The dimension of the portion of the pole body 31 located at the installation groove 34 in the radial direction A is d2 mm.

[0098] In some embodiments, the installation groove 34 includes a groove wall, and the groove wall includes a first surface 341. The first surface 341 is parallel to the first direction Z. There is a gap between the first surface 341 and the seal 4, that is, there is a gap between the part of the pole 3 located in the installation groove 34 and the seal 4. The pole 3 has a radial direction A perpendicular to the first direction Z. In the radial direction A, the size of the gap is g mm, satisfying: 0 ≤ g ≤ 2.

[0099] Please refer to Figure 6 , the fit between the pole 3 and the seal 4 is a clearance fit. The seal 4 needs to be deformed to achieve the sealing function. The clearance fit between the pole 3 and the seal 4 can allow the seal 4 to reserve more allowance for its deformation due to abutting against the cover plate 2, ensuring the sealing effect. Of course, the size of the gap cannot be too large, otherwise it will affect the stability of the seal 4 in the installation groove 34. When 0 ≤ g ≤ 2 is satisfied, it can not only ensure that the deformation of the seal 4 is within a controllable range, but also ensure that the seal 4 will be restricted in the installation groove 34.

[0100] When measuring g, since the mating surface of the seal 4 is inside the installation groove 34, it is very difficult to directly measure the value of g.

[0101] It can be achieved by calculating the difference between the inner diameter of the seal 4 and the outer diameter of the pole body 31 between the limiting part 33 and the base 32.

[0102] When measuring the inner diameter of the seal 4, two points farthest apart in the radial direction A of the seal can be taken, and the distance between these two points of the seal 4 is measured by a length measuring tool. After measuring multiple times and taking the average value, the inner diameter of the seal 4 is obtained.

[0103] In this embodiment, the inner diameter of the seal 4 can be set in the range of 2 mm - 23 mm, and the outer diameter can also be set in the range of 3 mm - 25 mm. In other embodiments, it can be set according to actual needs.

[0104] Next, specific embodiments and comparative examples of the battery of the present application are also provided, and the present application is described in more detail through the specific embodiments and comparative examples.

[0105] Among them, whether the seal fails can be judged by observing whether the seal is broken or skewed. If it is broken or skewed, the seal fails; if it is not broken or skewed, it does not fail.

[0106]

[0107]

[0108] As can be seen from the above embodiments, when -0.5 < t - h < 2 is satisfied, the seal does not break or skew, the seal does not fail, and the sealing effect can be better guaranteed, improving the service life of the single cell.

[0109] This embodiment also provides a battery pack, including a box body and single cells. The single cells are placed inside the housing and are electrically connected to each other.

[0110] A plurality of single cells are provided and arranged in several rows. The single cells are electrically connected to their adjacent single cells, and all the single cells are electrically connected in series or in parallel.

[0111] Due to the above-mentioned single cells being provided, the seal can be kept in the installation groove, thereby preventing problems such as falling off and misalignment, preventing the sealing function from failing, avoiding affecting the battery safety, and reducing potential risks such as liquid leakage and short circuit.

[0112] The above are only the preferred embodiments of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the technical principle of the present invention, several improvements and replacements can be made, and these improvements and replacements should also be regarded as the protection scope of the present invention.

Claims

1. A single cell battery, characterized in that: include: A shell having a first direction (Z), wherein one end of the shell along the first direction (Z) has an opening, and the shell further has a receiving cavity connected to the opening; A top cover (1) comprises a cover plate (2), a pole (3) and a sealing member (4); the cover plate (2) is arranged on the opening and connected to the shell; the cover plate (2) is provided with a through hole (21) penetrating the cover plate (2) along the first direction (Z); the pole (3) is provided with the through hole (21); the pole (3) has a mounting groove (34) arranged along the circumference of the pole; and the sealing member (4) is arranged in the mounting groove in a circumferential direction of the pole; In the first direction (Z), the maximum dimension of the mounting groove (34) is t mm, and the maximum dimension of the sealing element (4) is h mm, satisfying: -0.5<th<2.

2. The single cell according to claim 1, characterized in that: The pole (3) comprises a pole body (31), a base (32) and a limiting portion (33); the cross-sectional area of ​​the pole body (31) is smaller than the cross-sectional area of ​​the limiting portion (33); the pole body (31) is passed through the through hole (21); the base (32) is arranged at one end of the pole body (31) facing the accommodating cavity; the limiting portion (33) is arranged around the outer peripheral surface of the pole body (31); the limiting portion (33) and the base (32) are arranged at intervals in the first direction (Z); the base (32), the limiting portion (33) and the pole body (31) between the limiting portion (33) and the base (32) jointly enclose the mounting groove (34).

3. The single cell according to claim 1, characterized in that: The maximum dimension of the sealing element (4) is h mm, satisfying: 0.1≤h≤3.

4. The single cell according to claim 1, characterized in that: The mounting groove (34) comprises a first surface (341), a second surface (342) and a third surface (343), the first surface (341) is parallel to the first direction (Z), the second surface (342) is arranged obliquely relative to the first surface (341), the second surface (342) is arranged on a side of the first surface (341) facing the accommodating cavity, the third surface (343) is arranged obliquely relative to the first surface (341), and the third surface (343) is arranged on a side of the first surface (341) facing away from the accommodating cavity; The shape of the portion of the sealing element (4) located in the installation groove (34) is adapted to the shape of the installation groove (34).

5. The single cell according to claim 4, characterized in that: In a cross section of the installation groove (34) along the first direction (Z), the angle between the second surface (342) and the third surface (343) is α°, satisfying: 0°<α°≤160°.

6. The single cell according to claim 2, characterized in that: The base (32) further comprises a base body (321) and a step portion (322); the base body (321) is arranged at one end of the pole body (31) facing the accommodating cavity; the step portion (322) is arranged on the base body (321) and is located on a side of the base body (321) facing the limiting portion (33); the step portion (322) and the limiting portion (33) are arranged at intervals; the step portion (322), the limiting portion (33) and the outer peripheral surface of the pole body (31) between the step portion (322) and the limiting portion (33) together enclose the mounting groove (34).

7. The single cell according to claim 1, characterized in that: Satisfies: 0.4≤t≤2.

8. The single cell according to claim 2, characterized in that: The pole (3) has a radial direction (A) perpendicular to the first direction (Z), the dimension of the limiting portion (33) in the radial direction (A) is d1 mm, and the dimension of the mounting groove (34) on the pole body (31) in the radial direction (A) is d2 mm, satisfying: 0.1≤d1-d2≤5.

9. The single cell according to claim 1, characterized in that: The mounting groove (34) comprises a first surface (341), the first surface (341) is parallel to the first direction (Z), a gap is provided between the first surface (341) and the sealing member (4), the pole (3) has a radial direction (A) perpendicular to the first direction (Z), and in the radial direction (A), a size of the gap is g mm, satisfying: 0≤g≤2.

10. A battery pack, characterized in that: include: Box; A plurality of single cells according to any one of claims 1 to 9 are arranged inside a casing and are electrically connected to each other.

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