Lithium-ion cylindrical battery

Abstract

The utility model relates to a kind of lithium ion cylindrical battery, belong to lithium battery technical field;Wherein lithium ion cylindrical battery includes upper cover, explosion-proof sheet, outer insulating ring and shell;Explosion-proof sheet is oppositely arranged with upper cover along vertical direction;Explosion-proof sheet is located below upper cover, and the outer edge of explosion-proof sheet and the outer edge of upper cover mutually contact;Outer insulating ring is sleeved in the outer periphery of explosion-proof sheet and upper cover;Outer insulating ring includes main part, and main part extends along the axial direction of outer insulating ring;The inside of main part and upper cover and / or explosion-proof sheet contact;The inside of shell and the outside of main part contact;The ratio of the wall thickness of main part along the radial direction of outer insulating ring and the radius of cylindrical battery is between 5.7%~7.2%, so that main part can produce sufficient elastic deformation when being extruded by shell, guarantee the sealing effect of outer insulating ring to battery interior, and also can avoid the problem such as rebound force too strong, assembly difficult and battery overall size increase due to wall thickness too large.

Description

Technical Field

[0001] This utility model belongs to the field of battery technology, and in particular relates to a lithium-ion cylindrical battery. Background Technology

[0002] The outer insulating ring is an important component of the battery. It is fitted around both the top cover and the explosion-proof sheet. The outer circumference of the outer insulating ring can also contact the inner wall of the outer casing and be squeezed by the casing, so that the outer insulating ring can fix the top cover and the explosion-proof sheet and seal the inside of the battery.

[0003] The patent (publication number CN116345025A) discloses a cylindrical battery that is easy to process. By designing the dimensions of the mating part between the outer shell and the outer insulating ring, the battery can ensure the clamping effect of the outer shell on the outer insulating ring, thereby ensuring the sealing performance of the outer insulating ring.

[0004] The sealing of the battery by the outer insulating ring is mainly achieved through its compressibility. If the radial wall thickness of the outer insulating ring is too small, its elastic deformation is limited, resulting in a weaker sealing effect on the battery's interior. Conversely, if the radial wall thickness is too large, the ring experiences greater rebound force, making it more difficult for the outer casing to compress it, and also increasing the overall size of the battery. Therefore, maintaining the radial wall thickness of the outer insulating ring within a reasonable range is crucial not only for its sealing effect on the battery's interior but also for its overall battery dimensions.

[0005] In view of the above, this application is hereby submitted. Utility Model Content

[0006] To address the shortcomings of related technologies, this utility model provides a cylindrical lithium-ion battery. By limiting the wall thickness of the outer insulating ring, the outer insulating ring can have greater elastic deformation, providing a good sealing effect for the battery interior. At the same time, it can avoid problems such as excessive rebound force, assembly difficulties, and increased overall battery size caused by excessive wall thickness.

[0007] This utility model provides a lithium-ion cylindrical battery, comprising:

[0008] Top cover;

[0009] An explosion-proof sheet is vertically opposite to the upper cover plate; the explosion-proof sheet is located below the upper cover plate, and the outer edge of the explosion-proof sheet is in contact with the outer edge of the upper cover plate.

[0010] An outer insulating ring, which is fitted around the outer periphery of the explosion-proof sheet and the upper cover plate; the outer insulating ring includes:

[0011] The main body extends axially along the outer insulating ring; the inner side of the main body contacts the upper cover plate and / or the explosion-proof plate.

[0012] The outer casing is located on the outer periphery of the outer insulating ring and is used to apply a fastening force to the outer insulating ring. The fastening force is directed radially towards the central axis of the outer insulating ring. The inner wall of the outer casing is in contact with the outer side of the main body.

[0013] The ratio of the wall thickness L22 of the main body along the radial direction of the outer insulating ring to the radius R1 of the cylindrical battery is greater than or equal to 5.7% and less than or equal to 7.2%.

[0014] In the technical solution, by limiting the ratio of the radial wall thickness L22 of the main body of the outer insulating ring to the radius R1 of the cylindrical battery to between 5.7% and 7.2%, the elastic deformation and rebound force of the outer insulating ring are balanced, so that the main body has sufficient radial wall thickness to generate effective elastic deformation, thereby achieving reliable sealing of the battery interior; while avoiding excessive wall thickness that would cause a surge in rebound force and increase the difficulty of pressing the outer casing, and effectively controlling the overall size of the battery.

[0015] In some embodiments, the wall thickness L22 of the main body portion along the radial direction of the outer insulating ring is greater than or equal to 0.6 mm and less than or equal to 0.76 mm.

[0016] In some embodiments, the outer insulating ring further includes an upper connecting portion, the width direction of which is arranged radially along the outer insulating ring; one end of the upper connecting portion in the width direction is connected to the upper end of the main body, and the other end of the upper connecting portion in the width direction is arranged toward the central axis of the outer insulating ring; the lower surface of the upper connecting portion contacts the upper surface of the upper cover plate.

[0017] The ratio of the width L20 of the upper connecting part along the radial direction of the outer insulating ring to the radius R1 of the cylindrical battery is greater than or equal to 21% and less than or equal to 30.5%.

[0018] In some embodiments, the upper connecting part is provided with an upturned portion at one end facing the central axis of the outer insulating ring. The lower surface of the upturned portion is provided in a direction away from the upper cover plate along the axial direction of the outer insulating ring to reduce the contact area between the upper connecting part and the upper cover plate. The ratio of the width L21 of the upturned portion along the radial direction of the outer insulating ring to the radius R1 of the cylindrical battery is greater than or equal to 5.7% and less than or equal to 7.6%.

[0019] In some embodiments, the maximum distance from the upturned portion to the upper cover plate is H20, where H20 is greater than or equal to 0.53 mm and less than or equal to 0.73 mm.

[0020] In some embodiments, the housing is provided with an upper limit stop, which contacts the upper surface of the upper connecting part and is used to apply downward pressure to the upper connecting part; after the upper connecting part contacts the upper limit stop, the minimum thickness of the upper connecting part is H21, which is greater than or equal to 0.31 mm and less than or equal to 0.41 mm.

[0021] In some embodiments, the outer insulating ring further includes a lower connecting portion, the width direction of which is arranged radially along the outer insulating ring; one end of the lower connecting portion in the width direction is connected to the lower end of the main body, and the other end of the lower connecting portion in the width direction is arranged toward the central axis of the outer insulating ring; the upper surface of the lower connecting portion is in contact with the lower surface of the explosion-proof sheet.

[0022] The ratio of the width L23 of the lower connection portion along the radial direction of the outer insulating ring to the radius R1 of the cylindrical battery is greater than or equal to 17.1% and less than or equal to 26.7%.

[0023] In some embodiments, the lower connection portion has a recessed portion at one end facing the central axis of the outer insulating ring. The upper surface of the recessed portion is arranged along the axial direction of the outer insulating ring in a direction away from the explosion-proof sheet to reduce the contact area between the lower connection portion and the explosion-proof sheet. The ratio of the radial width L24 of the recessed portion along the outer insulating ring to the radius R1 of the cylindrical battery is greater than or equal to 4.8% and less than or equal to 10.5%.

[0024] In some embodiments, the housing is provided with a lower limiting portion, which contacts the lower surface of the lower connecting portion to apply upward pressure to the lower connecting portion; after the lower connecting portion contacts the lower limiting portion, the minimum thickness of the lower connecting portion is H22, which is greater than or equal to 0.25 mm and less than or equal to 0.41 mm.

[0025] In some embodiments, the radius R1 of the cylindrical battery is greater than or equal to 9.5 mm and less than or equal to 11.5 mm.

[0026] Based on the above technical solution, in this embodiment of the utility model, the lithium-ion cylindrical battery limits the wall thickness of the outer insulating ring to ensure that when the outer insulating ring is squeezed by the outer shell, it can generate sufficient elastic deformation to achieve reliable sealing of the battery interior, preventing electrolyte leakage and the entry of external contaminants, while avoiding problems such as excessive rebound force, assembly difficulties, and increased overall battery size caused by excessive wall thickness. Attached Figure Description

[0027] The accompanying drawings, which are included to provide a further understanding of the present invention and form part of this application, illustrate exemplary embodiments of the present invention and, together with the description thereof, serve to explain the present invention and do not constitute an undue limitation thereof. In the drawings:

[0028] Figure 1 This is a schematic diagram of the structure of one embodiment of the lithium-ion cylindrical battery of this utility model;

[0029] Figure 2 for Figure 1 Enlarged view of a portion of point A in the middle;

[0030] Figure 3This is a schematic diagram showing the dimensions of the outer insulating ring portion in one embodiment of the lithium-ion cylindrical battery of this utility model;

[0031] Figure 4 This is a schematic diagram showing the dimensions of another part of the outer insulating ring in one embodiment of the lithium-ion cylindrical battery of this utility model.

[0032] In the picture:

[0033] 1. Top cover plate; 2. Explosion-proof sheet; 3. Inner rubber ring; 4. Bottom cover plate; 5. Outer insulating ring; 6. Outer shell; 7. Face pad; 8. Sheath;

[0034] 51. Main body; 52. Upper connecting part; 53. Lower connecting part;

[0035] 521. Upward curve; 531. Downward curve;

[0036] 61. Upper limit part; 62. Lower limit part. Detailed Implementation

[0037] The technical solutions in the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this utility model, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this utility model without creative effort are within the scope of protection of this utility model.

[0038] In the description of this utility model, it should be understood that the terms "center", "lateral", "longitudinal", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", and "outer" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and 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. Therefore, they should not be construed as limitations on this utility model.

[0039] The terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first," "second," or "third" may explicitly or implicitly include one or more of that feature.

[0040] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of 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.

[0041] As attached Figures 1-4 As shown in an illustrative embodiment of the lithium-ion cylindrical battery of this utility model, the lithium-ion cylindrical battery includes an upper cover plate 1, an explosion-proof sheet 2, an outer insulating ring 5, and a shell 6; the explosion-proof sheet 2 and the upper cover plate 1 are arranged opposite each other in the vertical direction; the explosion-proof sheet 2 is located below the upper cover plate 1, and the outer edge of the explosion-proof sheet 2 is in contact with the outer edge of the upper cover plate 1; the outer insulating ring 5 is sleeved on the outer periphery of the explosion-proof sheet 2 and the upper cover plate 1, and the central axis of the outer insulating ring 5 is arranged in the vertical direction; the shell 6 is disposed on the outer periphery of the outer insulating ring 5 and is used to apply a fastening force to the outer insulating ring 5, the fastening force being radially directed towards the central axis of the outer insulating ring 5, so that the outer insulating ring 5 can seal the inside of the battery.

[0042] like Figure 1 As shown, the lithium-ion cylindrical battery also includes an inner rubber ring 3 and a lower cover plate 4. The explosion-proof sheet 2 is located on the upper side of the inner rubber ring 3, and the lower cover plate 4 is located on the lower side of the inner rubber ring 3. The inner rubber ring 3 is used to isolate the explosion-proof sheet 2 from the lower cover plate 4. The middle part of the inner rubber ring 3 is provided with a through hole, and the middle part of the lower cover plate 4 and the middle part of the explosion-proof sheet 2 are welded through the through hole to realize the transmission of current between the lower cover plate 4 and the explosion-proof sheet 2. The side of the lower cover plate 4 away from the explosion-proof sheet 2 is also welded to the positive electrode current collector.

[0043] like Figure 2 As shown, the outer shell 6 is provided with a cover film 8, which covers the outer surface of the outer shell 6 and is used to cover the outer shell 6, making the lithium-ion cylindrical battery aesthetically pleasing. The cover film 8 is usually made of insulating materials such as plastic, which can insulate the battery.

[0044] like Figure 2 As shown, the top of the outer insulating ring 5 is provided with a face pad 7, and the sleeve 8 covers the top of the face pad 7. The face pad 7 is in contact with the sleeve 8. The face pad 7 is not only used for insulation, but also for supporting the sleeve 8.

[0045] It should be noted that the inner rubber ring 3, the lower cover plate 4, the sleeve film 8, and the face pad 7 are existing technologies in this field and will not be described in detail here.

[0046] like Figure 3As shown, the outer insulating ring 5 includes a main body 51, which extends along the axial direction of the outer insulating ring 5. The inner side of the main body 51 contacts the upper cover plate 1 and / or the explosion-proof sheet 2, and the outer side of the main body 51 contacts the inner side of the outer shell 6, so that the outer shell 6 presses the main body 51 to fix the outer insulating ring 5.

[0047] The outer insulating ring 5 includes an upper connecting portion 52, the width of which is arranged radially along the outer insulating ring 5; one end of the upper connecting portion 52 in the width direction is connected to the upper end of the main body portion 51, and the other end of the upper connecting portion 52 in the width direction is arranged toward the central axis of the outer insulating ring 5; the lower surface of the upper connecting portion 52 is in contact with the upper surface of the upper cover plate 1.

[0048] The outer insulating ring 5 includes a lower connecting portion 53, the width of which is arranged radially along the outer insulating ring 5; one end of the lower connecting portion 53 in the width direction is connected to the lower end of the main body portion 51, and the other end of the lower connecting portion 53 in the width direction is arranged toward the central axis of the outer insulating ring 5; the upper surface of the lower connecting portion 53 is in contact with the lower surface of the explosion-proof sheet 2.

[0049] It should be noted that the main body 51, the upper connecting part 52 and the lower connecting part 53 are connected to each other to form a groove. The groove opening is set towards the central axis of the outer insulating ring 5. The outer edge of the upper cover plate 1 and the outer edge of the explosion-proof sheet 2 are set from the groove opening into the groove so that the upper cover plate 1 and the explosion-proof sheet 2 are connected and fixed to each other through the outer insulating ring 5.

[0050] The outer insulating ring 5 is made of a soft, elastic material, such as rubber or silicone. By compressing the outer insulating ring 5, it undergoes elastic deformation, thereby achieving a high degree of sealing to the inside of the battery. Furthermore, the elastic material of the outer insulating ring 5 allows it to be easily fitted onto the outer periphery of the upper cover plate 1 and the explosion-proof sheet 2.

[0051] like Figure 3 As shown, the ratio of the radial wall thickness L22 of the main body 51 along the outer insulating ring 5 to the radius R1 of the cylindrical battery is greater than or equal to 5.7% and less than or equal to 7.2%, so that the main body 51 has sufficient radial wall thickness to generate effective elastic deformation, thereby achieving a reliable seal to the inside of the battery; while avoiding excessive wall thickness that would cause a surge in rebound force and increase the difficulty of pressing the outer casing 6 against the outer insulating ring 5, and at the same time avoiding an increase in the overall size of the battery.

[0052] It should be noted that, for ease of description, the wall thickness of the main body 51 along the radial direction of the outer insulating ring 5 is referred to as the wall thickness of the main body 51, the width of the upper connecting part 52 along the radial direction of the outer insulating ring 5 is referred to as the width of the upper connecting part 52, and the width of the lower connecting part 53 along the radial direction of the outer insulating ring 5 is referred to as the width of the lower connecting part 53.

[0053] If the ratio of the wall thickness of the main body 51 to the radius of the cylindrical battery is too large, the wall thickness of the main body 51 will be large. When the outer casing 6 presses the outer insulating ring 5 to seal, the clamping force required for the outer insulating ring 5 will be large, the clamping difficulty of the outer insulating ring 5 will increase, and the rebound of the outer insulating ring 5 will be large. Furthermore, if the wall thickness of the main body 51 is large, the wall thickness of the main body 51 will still be large after the clamping force is applied by the outer casing 6, which will lead to an increase in the size of the battery.

[0054] If the ratio of the wall thickness of the main body 51 to the radius of the cylindrical battery is too small, the elastic deformation of the main body 51 will be limited, and the sealing reliability of the battery will be reduced.

[0055] like Figure 3 As shown, the wall thickness L22 of the main body 51 along the radial direction of the outer insulating ring 5 is greater than or equal to 0.6 mm and less than or equal to 0.76 mm.

[0056] In some embodiments, the wall thickness L22 of the main body 51 along the radial direction of the outer insulating ring 5 is 0.68 mm.

[0057] The radius R1 of the cylindrical battery is greater than or equal to 9.5 mm and less than or equal to 11.5 mm.

[0058] In some embodiments, the radius R1 of the cylindrical battery is 10.5 mm.

[0059] It should be noted that the wall thickness of the main body 51 along the radial direction of the outer insulating ring 5 may not be uniform. When the wall thickness of the main body 51 along the radial direction of the outer insulating ring 5 is not uniform, the wall thickness of the main body 51 along the radial direction of the outer insulating ring 5 refers to the minimum wall thickness of the main body 51 along the radial direction of the outer insulating ring 5.

[0060] like Figure 3 As shown, the ratio of the width L20 of the upper connecting part 52 along the radial direction of the outer insulating ring 5 to the radius R1 of the cylindrical battery is greater than or equal to 21% and less than or equal to 30.5%, so that there is sufficient contact area between the upper connecting part 52 and the upper cover plate 1, ensuring the fixing effect of the outer insulating ring 5 on the upper cover plate 1, and the outer insulating ring 5 has a good sealing effect on the inside of the battery, while avoiding the upper connecting part 52 being too wide and interfering with the protrusion on the upper cover plate 1, thus affecting the assembly.

[0061] If the ratio of the width of the upper connecting part 52 to the radius of the cylindrical battery is too large, although the contact area between the upper connecting part 52 and the upper cover plate 1 is large, the outer insulating ring 5 has a good fixing effect on the upper cover plate 1, and the outer insulating ring 5 has a good sealing effect on the inside of the battery, the upper connecting part 52 is prone to interference with the protrusion on the upper cover plate 1.

[0062] If the ratio of the width of the upper connecting part 52 to the radius of the cylindrical battery is too small, the contact area between the upper connecting part 52 and the upper cover plate 1 will be reduced, the creep of the outer insulating ring 5 will be small, and the sealing effect of the outer insulating ring 5 on the inside of the battery will be poor.

[0063] In some embodiments, the width L20 of the upper connecting portion 52 is 2.7 mm.

[0064] When the width L20 of the upper connecting part 52 along the radial direction of the outer insulating ring 5 is 2.7 mm and the radius R1 of the cylindrical battery is 10.5 mm, the ratio of the width L20 of the upper connecting part 52 along the radial direction of the outer insulating ring 5 to the radius R1 of the cylindrical battery is 25.7%.

[0065] In some embodiments, such as Figure 3 and Figure 4 As shown, the upper connecting part 52 is provided with an upturned part 521 at one end facing the central axis of the outer insulating ring 5. The lower surface of the upturned part 521 is arranged along the axial direction of the outer insulating ring 5 in a direction away from the upper cover plate 1, so as to reduce the contact area between the upper connecting part 52 and the upper cover plate 1, reduce the frictional resistance during assembly to facilitate installation. At the same time, the elastic structure of the upturned part 521 can provide appropriate cushioning when under pressure, and enhance the adaptability to fixing the upper cover plate 1.

[0066] like Figure 3 As shown, the ratio of the width L21 of the upturned portion 521 along the radial direction of the outer insulating ring 5 to the radius R1 of the cylindrical battery is greater than or equal to 5.7% and less than or equal to 7.6%.

[0067] For ease of description, the width of the upturned portion 521 along the radial direction of the outer insulating ring 5 is simply referred to as the width of the upturned portion 521.

[0068] If the ratio of the width of the upturned portion 521 to the radius of the cylindrical battery is too small, the creep of the outer insulating ring 5 will be small, the sealing effect of the outer insulating ring 5 on the inside of the battery will be poor, and the reliability of the seal cannot be guaranteed.

[0069] If the ratio of the width of the upturned portion 521 to the radius of the cylindrical battery is too large, the upturned portion 521 may interfere with the protrusion of the upper cover plate 1, affecting battery assembly.

[0070] In some embodiments, the width of the upturned portion 521 is 0.69 mm.

[0071] When the width of the upturned portion 521 is 0.69 mm and the radius R1 of the cylindrical battery is 10.5 mm, the ratio of the width L21 of the upturned portion 521 to the radius R1 of the cylindrical battery is 6.6%.

[0072] It should be noted that there is a gap between the upturned part 521 and the upper surface of the upper cover plate 1, and the gap increases in the radial direction of the outer insulating ring 5 toward the central axis of the outer insulating ring 5.

[0073] like Figure 4 As shown, the maximum distance from the upturned part 521 to the upper cover plate 1 is H20, where H20 is greater than or equal to 0.53 mm and less than or equal to 0.73 mm.

[0074] If the maximum distance between the upturned part 521 and the upper cover plate 1 is too large, it will easily affect the placement of the face pad 7 and the assembly of the battery; if the maximum distance between the upturned part 521 and the upper cover plate 1 is too small, the creep of the outer insulating ring 5 will be small, the compression of the outer insulating ring 5 will be small, and the reliability of the battery seal will be affected.

[0075] In some embodiments, the maximum distance H20 from the upturned portion 521 to the upper cover plate 1 is 0.63 mm.

[0076] like Figure 4 As shown, the ratio of the width L23 of the lower connecting part 53 along the radial direction of the outer insulating ring 5 to the radius R1 of the cylindrical battery is greater than or equal to 17.1% and less than or equal to 26.7%.

[0077] If the ratio of the width of the lower connecting part 53 to the radius of the cylindrical battery is too large, although the contact area between the lower connecting part 53 and the explosion-proof sheet 2 is large, the outer insulating ring 5 has a good fixing effect on the explosion-proof sheet 2, and the outer insulating ring 5 has a good sealing effect on the inside of the battery, the lower connecting part 53 is prone to interfere with the winding core inside the battery.

[0078] If the ratio of the width of the lower connecting part 53 to the radius of the cylindrical battery is too small, the contact area between the lower connecting part 53 and the explosion-proof sheet 2 will be reduced, the creep of the outer insulating ring 5 will be small, and the sealing effect of the outer insulating ring 5 on the inside of the battery will be poor.

[0079] In some embodiments, the width L23 of the lower connecting portion 53 is 2.3 mm.

[0080] When the width L23 of the lower connecting part 53 is 2.3mm and the radius R1 of the cylindrical battery is 10.5mm, the ratio of the width L23 of the lower connecting part 53 to the radius R1 of the cylindrical battery is 21.9%.

[0081] like Figure 3 As shown, the lower connecting part 53 is provided with a recessed part 531 at one end facing the central axis of the outer insulating ring 5. The upper surface of the recessed part 531 is provided in a direction away from the explosion-proof sheet 2 along the axial direction of the outer insulating ring 5, so as to reduce the contact area between the lower connecting part 53 and the explosion-proof sheet 2.

[0082] like Figure 4 As shown, the ratio of the width L24 of the recessed portion 531 along the radial direction of the outer insulating ring 5 to the radius R1 of the cylindrical battery is greater than or equal to 4.8% and less than or equal to 10.5%.

[0083] For ease of description, the width of the recessed portion 531 along the radial direction of the outer insulating ring 5 is simply referred to as the width of the recessed portion 531.

[0084] If the ratio of the width of the recessed portion 531 to the radius of the cylindrical battery is too small, the creep of the outer insulating ring 5 will be small, the sealing effect of the outer insulating ring 5 on the inside of the battery will be poor, and the reliability of the seal cannot be guaranteed.

[0085] If the ratio of the width of the recessed portion 531 to the radius of the cylindrical battery is too large, the recessed portion 531 may interfere with the winding core inside the battery, causing mutual compression and easily leading to short circuit failure.

[0086] In some embodiments, the width L24 of the recessed portion 531 along the radial direction of the outer insulating ring 5 is 0.8 mm.

[0087] When the radial width L24 of the recessed portion 531 along the outer insulating ring 5 is 0.8 mm and the radius R1 of the cylindrical battery is 10.5 mm, the ratio of the radial width L24 of the recessed portion 531 along the outer insulating ring 5 to the radius R1 of the cylindrical battery is 7.6%.

[0088] It should be noted that the upper surface of the recessed part 531 and the lower surface of the explosion-proof sheet 2 have a gap in the vertical direction, and the gap increases in the direction close to the central axis of the outer insulating ring 5.

[0089] like Figure 3 and Figure 4 As shown, the outer casing 6 is provided with an upper limit part 61, which contacts the upper surface of the upper connecting part 52 and is used to apply downward pressure to the upper connecting part 52 so that the outer casing 6 can be squeezed and fixed to the outer insulating ring 5.

[0090] In some embodiments, the upper limit portion 61 is a flange on the top of the housing 6.

[0091] like Figure 4 As shown, after the upper connecting part 52 contacts the upper limit part 61, the minimum thickness of the upper connecting part 52 is H21, which is greater than or equal to 0.31 mm and less than or equal to 0.41 mm.

[0092] If the minimum thickness H21 of the upper connecting part 52 is too small after being squeezed by the upper limit part 61, the compression of the outer insulating ring 5 will be too large, and the outer insulating ring 5 will easily undergo plastic deformation, resulting in the failure of the outer insulating ring 5 to seal the inside of the battery.

[0093] If the minimum thickness H21 of the upper connecting part 52 is too large after being squeezed by the upper limit part 61, the compression of the outer insulating ring 5 will be too small, and the sealing effect of the outer insulating ring 5 on the inside of the battery will be poor.

[0094] In some embodiments, after the upper connecting portion 52 is pressed by the upper limit portion 61, the minimum thickness H21 of the upper connecting portion 52 is 0.36 mm.

[0095] like Figure 3 As shown, the outer casing 6 is provided with a lower limit part 62, which contacts the lower surface of the lower connecting part 53 and is used to apply upward pressure to the lower connecting part 53 so that the outer casing 6 can be squeezed and fixed to the outer insulating ring 5.

[0096] In some embodiments, the outer casing 6 protrudes toward the central axis of the outer insulating ring 5 to form a lower limiting portion 62, while a groove is formed on the outer periphery of the outer casing 6.

[0097] like Figure 4 As shown, after the lower connecting part 53 contacts the lower limiting part 62, the minimum thickness of the lower connecting part 53 is H22, which is greater than or equal to 0.25 mm and less than or equal to 0.41 mm.

[0098] If the minimum thickness H22 of the lower connecting part 53 is too small after being squeezed by the lower limiting part 62, the compression of the outer insulating ring 5 will be too large, and the outer insulating ring 5 will easily undergo plastic deformation, resulting in the failure of the outer insulating ring 5 to seal the inside of the battery.

[0099] If the minimum thickness H22 of the lower connecting part 53 is too large after being squeezed by the lower limiting part 62, the compression of the outer insulating ring 5 will be too small, and the sealing effect of the outer insulating ring 5 on the inside of the battery will be poor.

[0100] In some embodiments, after the lower connecting portion 53 is pressed by the lower limiting portion 62, the minimum thickness H22 of the lower connecting portion 53 is 0.33 mm.

[0101] Through the description of several embodiments of the lithium-ion cylindrical battery of this utility model, it can be seen that the embodiments of the lithium-ion cylindrical battery of this utility model have at least one or more of the following advantages:

[0102] 1. The outer insulating ring 5 is made of elastic materials such as rubber and silicone, which not only makes it easy to be fitted around the upper cover plate 1 and the explosion-proof sheet 2, but also can achieve effective sealing of the battery interior by generating elastic deformation through compression; the outer casing 6 is provided with an upper limit part 61 and a lower limit part 62, so that the upper limit part 61 and the lower limit part 62 apply pressure to the upper connecting part 52 and the lower connecting part 53 respectively, so as to increase the compression and fixing effect of the outer insulating ring 5.

[0103] 2. By making the ratio of the radial wall thickness of the main body 51 to the battery radius between 5.7% and 7.2%, not only can the outer insulating ring 5 generate sufficient and effective elastic deformation when squeezed by the outer casing 6, thus providing a reliable seal for the inside of the battery and preventing electrolyte leakage and intrusion of external contaminants, but also the problems of excessive wall thickness increasing the difficulty of pressing the outer casing 6 and the large size of the battery can be avoided.

[0104] 3. By making the ratio of the width of the upper connecting part 52 to the radius of the battery between 21% and 30.5%, not only can the contact area with the upper cover plate 1 be guaranteed, increasing the fixing effect of the outer insulating ring 5 on the upper cover plate 1 and the sealing performance of the battery interior be improved, but also interference with the upper cover plate 1 protrusion caused by the upper connecting part 52 being too wide can be avoided. By making the minimum thickness of the upper connecting part 52 after being compressed between 0.31mm and 0.41mm, the upper connecting part 52 can have a reasonable amount of compression, avoiding poor sealing due to insufficient compression, and preventing failure due to excessive compression caused by plastic deformation.

[0105] 4. By making the ratio of the width of the upturned portion 521 to the battery radius between 5.7% and 7.6%, and the maximum distance from the upturned portion 521 to the upper cover plate 1 between 0.53mm and 0.73mm, the assembly friction resistance can be reduced by decreasing the contact area, and the elastic structure can be used to provide buffering to enhance the fixation adaptability. At the same time, it avoids interference from the protrusion due to excessive width or affect the assembly of the pad 7 due to excessive distance.

[0106] 5. By making the ratio of the width of the lower connecting part 53 to the battery radius between 17.1% and 26.7%, not only can the contact area between the outer insulating ring 5 and the explosion-proof sheet 2 be guaranteed, increasing the fixing effect of the outer insulating ring 5 on the explosion-proof sheet 2 and the sealing performance of the battery interior, but also the interference between the lower connecting part 53 and the internal core should be avoided due to excessive width. By making the minimum thickness of the lower connecting part 53 after compression between 0.25mm and 0.41mm, the lower connecting part 53 has a reasonable amount of compression, which prevents poor sealing due to insufficient compression and avoids plastic deformation caused by excessive compression, thus ensuring the durability of fixing and sealing of the explosion-proof sheet 2.

[0107] 6. By making the ratio of the width of the recessed part 531 to the battery radius between 4.8% and 10.5%, not only can the assembly resistance of the explosion-proof sheet 2 be reduced by decreasing the contact area between the lower connecting part 53 and the explosion-proof sheet 2, but also the excessive width of the lower connecting part 53 can be avoided from interfering with the core and causing a short circuit.

[0108] Finally, it should be noted that the various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0109] The above embodiments are only used to illustrate the technical solution of this utility model and not to limit it; although the utility model has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications can still be made to the specific implementation of this utility model or equivalent substitutions can be made to some technical features without departing from the spirit of the technical solution of this utility model, and all such modifications and substitutions should be covered within the scope of the technical solution claimed by this utility model.

Claims

1. A lithium-ion cylindrical battery, characterized in that, include: Top cover plate (1); An explosion-proof sheet (2) is arranged vertically opposite to the upper cover plate (1); the explosion-proof sheet (2) is located below the upper cover plate (1), and the outer edge of the explosion-proof sheet (2) is in contact with the outer edge of the upper cover plate (1); An outer insulating ring (5) is fitted around the outer periphery of the explosion-proof sheet (2) and the upper cover plate (1); the outer insulating ring (5) includes: The main body (51) extends along the axial direction of the outer insulating ring (5); The inner side of the main body (51) is in contact with the upper cover plate (1) and / or the explosion-proof sheet (2); The outer casing (6) is disposed on the outer periphery of the outer insulating ring (5) and is used to apply a fastening force to the outer insulating ring (5); the inner wall of the outer casing (6) is in contact with the outer side of the main body (51); The ratio of the wall thickness L22 of the main body (51) along the radial direction of the outer insulating ring (5) to the radius R1 of the cylindrical battery is greater than or equal to 5.7% and less than or equal to 7.2%.

2. The lithium-ion cylindrical battery according to claim 1, characterized in that, The wall thickness L22 of the main body (51) along the radial direction of the outer insulating ring (5) is greater than or equal to 0.6 mm and less than or equal to 0.76 mm.

3. The lithium-ion cylindrical battery according to claim 1, characterized in that, The outer insulating ring (5) further includes an upper connecting portion (52), the width direction of which is arranged radially along the outer insulating ring (5); one end of the upper connecting portion (52) in the width direction is connected to the upper end of the main body (51), and the other end of the upper connecting portion (52) in the width direction is arranged toward the central axis of the outer insulating ring (5); the lower surface of the upper connecting portion (52) is in contact with the upper surface of the upper cover plate (1); The ratio of the width L20 of the upper connecting portion (52) along the radial direction of the outer insulating ring (5) to the radius R1 of the cylindrical battery is greater than or equal to 21% and less than or equal to 30.5%.

4. The lithium-ion cylindrical battery according to claim 3, characterized in that, The upper connecting part (52) is provided with an upturned part (521) at one end facing the central axis of the outer insulating ring (5). The lower surface of the upturned part (521) is arranged in a direction away from the upper cover plate (1) along the axial direction of the outer insulating ring (5). The ratio of the width L21 of the upturned part (521) along the radial direction of the outer insulating ring (5) to the radius R1 of the cylindrical battery is greater than or equal to 5.7% and less than or equal to 7.6%.

5. The lithium-ion cylindrical battery according to claim 4, characterized in that, The maximum distance between the upturned portion (521) and the upper cover plate (1) is H20, where H20 is greater than or equal to 0.53 mm and less than or equal to 0.73 mm.

6. The lithium-ion cylindrical battery according to claim 3, characterized in that, The outer casing (6) is provided with an upper limit stop (61), which contacts the upper surface of the upper connecting part (52) and is used to apply downward pressure to the upper connecting part (52); after the upper connecting part (52) contacts the upper limit stop (61), the minimum thickness of the upper connecting part (52) is H21, which is greater than or equal to 0.31 mm and less than or equal to 0.41 mm.

7. The lithium-ion cylindrical battery according to claim 1, characterized in that, The outer insulating ring (5) further includes a lower connecting portion (53), the width direction of which is arranged radially along the outer insulating ring (5); one end of the lower connecting portion (53) in the width direction is connected to the lower end of the main body (51), and the other end of the lower connecting portion (53) in the width direction is arranged toward the central axis of the outer insulating ring (5); the upper surface of the lower connecting portion (53) is in contact with the lower surface of the explosion-proof sheet (2); The ratio of the width L23 of the lower connecting portion (53) along the radial direction of the outer insulating ring (5) to the radius R1 of the cylindrical battery is greater than or equal to 17.1% and less than or equal to 26.7%.

8. The lithium-ion cylindrical battery according to claim 7, characterized in that, The lower connecting part (53) has a recessed part (531) at one end facing the central axis of the outer insulating ring (5). The upper surface of the recessed part (531) is arranged in a direction away from the explosion-proof sheet (2) along the axial direction of the outer insulating ring (5). The ratio of the width L24 of the recessed part (531) along the radial direction of the outer insulating ring (5) to the radius R1 of the cylindrical battery is greater than or equal to 4.8% and less than or equal to 10.5%.

9. The lithium-ion cylindrical battery according to claim 7, characterized in that, The outer casing (6) is provided with a lower limiting part (62), which contacts the lower surface of the lower connecting part (53) and is used to apply upward pressure to the lower connecting part (53); after the lower connecting part (53) contacts the lower limiting part (62), the minimum thickness of the lower connecting part (53) is H22, which is greater than or equal to 0.25 mm and less than or equal to 0.41 mm.

10. The lithium-ion cylindrical battery according to claim 1, characterized in that, The radius R1 of the cylindrical battery is greater than or equal to 9.5 mm and less than or equal to 11.5 mm.

Images