Cylindrical batteries, battery packs, and electronic devices

Abstract

The present invention provides a cylindrical battery, a battery pack, and an electronic device that can at least enhance the safety of cylindrical batteries. [Solution] The cylindrical battery includes a housing, an electrode assembly, and a cover plate. The housing has an opening at one end in the height direction of the cylindrical battery. The electrode assembly is located inside the housing and has a winding center hole. The cover plate covers the opening of the housing and has an explosion-proof valve region formed by being surrounded by an explosion-proof valve. The winding center hole is located within the orthogonal projection range in the height direction of the explosion-proof valve region of the cover plate. Here, the winding center hole has a diameter D1, and a portion of the cover plate has a diameter D2, with 35% ≥ D1 / D2 ≥ 10%.

Description

Technical Field

[0001] The present invention relates to a cylindrical battery, a battery pack, and an electronic device.

Background Art

[0002] In the field of new energy power batteries, a secondary battery refers to a rechargeable battery and is also called a renewable battery or a storage battery. Different from a primary battery, a secondary battery can perform multiple charge-discharge cycles by reverse charging, which is convenient for repeated use. A secondary battery generally includes an electrode assembly, a housing, a cover plate, etc. Secondary batteries include cylindrical batteries and square batteries. A cylindrical battery refers to a battery including a cylindrical cell, and includes a case and an electrode assembly. The electrode assembly includes a positive electrode sheet, a negative electrode sheet, and a separator located between the positive electrode sheet and the negative electrode sheet. These positive electrode sheet, negative electrode sheet, and separator are laminated with each other and then wound to form an electrode assembly, and then enclosed in a case.

Summary of the Invention

Problems to be Solved by the Invention

[0003] In view of the problems existing in the related art, an object of the present invention is to provide a cylindrical battery, a battery pack, and an electronic device that can at least improve the safety of the cylindrical battery.

Means for Solving the Problems

[0004] To achieve the above object, the present invention provides a cylindrical battery. The cylindrical battery includes a housing, an electrode assembly, and a cover plate. The housing has an opening at one end in the height direction of the cylindrical battery. The electrode assembly is located in the housing and has a winding center hole. The cover plate fits into the opening of the housing and has an explosion-proof valve region surrounded by an explosion-proof valve. The winding center hole is located within the orthographic projection range in the height direction of the explosion-proof valve region of the cover plate. Among them, the winding center hole has a diameter D1, a partial region of the cover plate has a diameter D2, and 35% ≧ D1 / D2 ≧ 10%.

[0005] In some embodiments, the housing has an outer diameter D3 such that 50% ≤ D2 / D3 ≤ 90%.

[0006] In some embodiments, the cylindrical battery has a height H and D2 > D1 ≥ 3%H.

[0007] In some embodiments, D3 > D2 ≥ 20%H.

[0008] In some embodiments, the range of D1 is 4 mm to 8 mm.

[0009] In some embodiments, the range of D2 is 27mm to 31mm, and the range of H is 80mm to 160mm.

[0010] In some embodiments, the explosion-proof valve is a notch on the surface of the cover plate facing the electrode assembly, with a range of H from 95 mm to 120 mm.

[0011] In some embodiments, a crimped portion protruding inward is provided on the side wall near the opening of the housing. The side wall has a curled edge extending inward on the side facing away from the electrode assembly of the crimped portion, and the cover plate is sandwiched between the crimped portion and the curled edge in the height direction.

[0012] A battery pack is further provided based on embodiments of the present invention. The battery pack may include a cylindrical battery of any one of the embodiments described above.

[0013] Further electronic devices are provided based on embodiments of the present invention. These electronic devices may include the battery pack described above.

[0014] The beneficial effects of the present invention include the following: [Effects of the Invention]

[0015] This invention allows the diameter D1 of the winding central hole to be set within an appropriate range by setting the ratio between the diameter D1 of the winding central hole and the diameter D2 corresponding to the weak point of the cover plate, thereby making the diameter D2 corresponding to the weak point sufficiently large. By considering both pressure relief from the weak point and gas discharge from the central hole, a sufficiently large pressure relief channel can be provided, which is beneficial for gas discharge. In the event of thermal runaway in the battery, the pressure can be relieved more favorably, ensuring the integrity of the battery body and improving the safety of the cylindrical battery. [Brief explanation of the drawing]

[0016] To more clearly illustrate embodiments of the present invention or technical solutions in the prior art, the accompanying drawings that may be used in describing embodiments or the prior art are briefly introduced below. The accompanying drawings described below represent only a few embodiments of the present invention, and it will be apparent to those skilled in the art that other embodiments can be derived from these drawings without expending any creative effort.

[0017] [Figure 1] This diagram shows a schematic representation of an embodiment of the present invention where the electronic device is in a vehicle. [Figure 2] This shows a perspective view of a cylindrical battery according to an embodiment of the present invention. [Figure 3] This shows a cross-sectional view of a cylindrical battery according to an embodiment of the present invention. [Modes for carrying out the invention]

[0018] For a clearer understanding of the spirit of the embodiments of the present invention, the present invention will be described in further detail below in combination with some preferred embodiments of the present invention.

[0019] Hereinafter, embodiments of the present invention will be described in detail. Throughout the entire text of the specification of the present invention, the same or similar components, and components having the same or similar functions are represented by similar reference numerals. Embodiments regarding the attached drawings described in this specification are of an illustrative, exemplary, and diagrammatic nature and are for providing a basic understanding of the present invention. Embodiments of the present invention should not be construed as limiting the present invention.

[0020] In this specification, terms such as "approximately", "substantially", "substantially", and "about" are used to describe and explain small variations, such as variations within the error range of a manufacturing process. When used in relation to an event or situation, the terms may refer to examples where the event or situation occurred exactly and examples where the event or situation occurred very approximately.

[0021] In this specification, unless otherwise specified or limited, relative terms such as, for example, "central", "vertical", "horizontal", "front", "rear", "right", "left", "inner", "outer", "lower", "higher", "horizontal", "vertical", "higher", "lower", "upper", "lower", "top", "bottom" and their derivatives (e.g., "horizontally", "downward", "upward") should be construed as referring to the directions described in the description or illustrated in the attached drawings. These relative terms are used only for convenience of explanation and do not require the present invention to be constructed or operated in a specific direction.

[0022] For convenience of explanation, "first", "second", "third", etc. may be used in this specification to distinguish different components in one figure or a series of figures. "First", "second", "third", etc. do not describe the corresponding components.

[0023] The present invention provides an electronic device 1000. In the following embodiments, for the sake of explanation, the electronic device 1000 will be described as a vehicle. Referring to Figure 1, a battery pack 1002 is provided inside the vehicle. The battery pack 1002 may be located at the bottom, top, or rear of the vehicle body 1001. The battery pack 1002 may be used to power the vehicle; for example, the battery pack 1002 may serve as the vehicle's operating power source. The operating unit of the electronic device 1000 and the battery pack 1002 are electrically connected to obtain energy support. The vehicle may be a fuel vehicle, a gas vehicle, or a new energy vehicle. The new energy vehicle may be, but is not limited to, a pure electric vehicle, a hybrid vehicle, or an extended-range vehicle. The operating unit is the vehicle body, and the battery pack 1002 is located at the bottom of the vehicle body, providing power support for the vehicle's operation or the operation of in-vehicle electrical components. However, in some other embodiments, the electronic device 1 may be a mobile phone, a portable device, a notebook computer, a ship, an airplane, an electric toy, a power tool, etc. Aircraft include airplanes, rockets, space shuttles, spacecraft, etc. The operating part is a unit member that acquires electrical energy from the battery pack 1002 and performs the corresponding operation, for example, a fan blade rotation unit, a vacuum cleaner dust collection unit, etc. Electric toys include stationary or mobile electric toys, for example, game consoles, electric car toys, electric boat toys, electric airplane toys, etc. Electric tools include metal cutting electric tools, grinding electric tools, assembly electric tools, and railway electric tools, for example, electric drills, electric grinders, electric wrenches, electric screwdrivers, electric hammers, impact drills, concrete vibrators, electric planes, etc. Embodiments of the present invention are not particularly limited to the electronic device 1000 described above.

[0024] Figure 2 shows a perspective view of a cylindrical battery 100 according to an embodiment of the present invention. Figure 3 shows a cross-sectional view of a cylindrical battery 100 according to an embodiment of the present invention.

[0025] In one example of the cylindrical battery of the present invention, combining FIGS. 2 and 3, the cylindrical battery 100 includes a housing 200. The housing 200 includes a side wall 109 and an end wall 111 at one end connected to the side wall 109. An opening 205 is provided at the other end of the side wall 109 opposite to the end wall 111. The cover plate 220 is used to enclose the electrode assembly 120 and the electrolyte together with the housing by fitting into the opening 205 of the housing 200. The material of the housing 200 may be any one of a plurality of available materials such as, for example, copper, iron, aluminum, steel, and aluminum alloy. The housing 200 may have a cylindrical shape and define a receiving cavity. The electrode assembly 120 is provided in the receiving cavity. The outer diameter of the housing 200 may be determined based on the specific diameter size of the electrode assembly 120, for example, 18 mm, 21 mm, 46 mm, etc. In some embodiments, the cylindrical battery 100 may be a 4680 cylindrical battery (outer diameter 46 mm, height 80 mm), or the cylindrical battery 100 may be a 4695 cylindrical battery (outer diameter 46 mm, height 95 mm), or the cylindrical battery 100 may be a 46120 cylindrical battery (outer diameter 46 mm, height 120 mm).

[0026] The electrode assembly 120 is mainly formed by sequentially laminating and winding a first electrode sheet, a second electrode sheet, and a separator located between the first electrode sheet and the second electrode sheet. In some embodiments of the present invention, the first electrode sheet may be a positive electrode sheet, and the second electrode sheet may be a negative electrode sheet. The wound electrode assembly 120 has a winding center hole 120c. The electrode assembly 120 has a first tab 121 and a second tab 122 on opposite sides in its height direction Hd. The second tab 122 faces the opening 205, and the first tab 121 faces the end wall 111 opposite to the opening 205. The direction from the first tab 121 to the second tab 122 is the height direction Hd of the electrode assembly 120. In some embodiments of the present invention, the first tab 121 may be a positive electrode tab, and the second tab may be a negative electrode tab. In some embodiments, the electrode assembly 120 may further include an insulating layer, such as an insulating tape, adhered to the outer periphery of the wound first electrode sheet, second electrode sheet, and separator.

[0027] In some embodiments, the positive electrode sheet (first electrode sheet) may include a positive electrode current collector and a positive electrode covering region. The positive electrode covering region is a covered portion of the positive electrode current collector. The positive electrode covering region is a positive electrode active material layer formed by covering it with positive electrode active material. The portion of the positive electrode current collector not covered by the positive electrode covering region constitutes a positive electrode tab (first tab 121). The negative electrode sheet (second tab) may include a negative electrode current collector and a negative electrode covering region. The negative electrode covering region is a covered portion of the negative electrode current collector. The negative electrode covering region is a negative electrode active material layer formed by covering it with negative electrode active material. The portion of the negative electrode current collector not covered by the negative electrode covering region constitutes a negative electrode tab (second tab 122).

[0028] Taking a lithium-ion battery as an example, the material of the positive electrode current collector may be aluminum. The positive electrode coating region may contain a positive electrode active material, which may be lithium cobalt oxide, lithium iron phosphate, ternary lithium, or lithium manganese oxide, etc. The material of the negative electrode current collector may be copper. The negative electrode coating region may contain a negative electrode active material, which may be carbon or silicon, etc. The material of the separator may be PP (polypropylene) or PE (polyethylene), etc.

[0029] A crimping portion 113 (which may also be called a roll groove) that protrudes inward is provided on the side wall of the housing 200 near the opening 205. The electrode assembly 120 is provided between the end wall 111 and the crimping portion 113, and the crimping portion 113 can restrict the movement of the electrode assembly 120 in the height direction Hd and the opposite direction between the end wall 111 and the crimping portion 113. The end of the side wall 109 of the housing 200 on the opening 205 side may form a curled edge portion 32. The curled edge portion 32 extends inward along the radial direction of the housing 200. The curled edge portion 32 and the crimping portion 113 are spaced apart along the height direction Hd, and both the crimping portion 113 and the curled edge portion 32 can clamp the cover plate 220. An insulating member 242 is provided between the cover plate 220 and the housing 200, thereby electrically insulating the cover plate 220 and the housing 200.

[0030] The cylindrical battery 100 further includes terminal posts 160. The terminal posts 160 penetrate the end wall 111 and are insulated from the end wall 111. The terminal posts 160 are electrically connected to the first tab 121 of the electrode assembly 120 by the first current collector plate 301, and the terminal posts 160 may be positively charged, for example. The second tab 122 is electrically connected to the housing by the second current collector plate 302, and the housing 200 may be negatively charged, for example. An insulating member 244 is provided between the terminal posts 160 and the housing 200 to electrically insulate the terminal posts 160 and the housing 200.

[0031] In one example of the cylindrical battery 100 of the present invention, the manufacturing method of the cylindrical battery 100 of the present invention includes the following steps:

[0032] Winding: The first electrode sheet, separator, and second electrode sheet are stacked and wound together to form a winding structure. The uncovered portions of the positive electrode current collector of the first electrode sheet and the negative electrode current collector of the second electrode sheet constitute the first tab 121 and the second tab 122. The first tab 121 and the second tab 122 are bent along the radial direction of the electrode assembly 120.

[0033] Welding of the current collector plate and electrode assembly: Specifically, the first current collector plate 301 and the second current collector plate 302 are welded to the surface areas of the bent first tab 121 and second tab 122, respectively.

[0034] Insertion into the housing: The electrode assembly 120, with the first current collector plate 301 and the second current collector plate 302 welded together, is installed into the housing 200 through the opening 205. The method of installing the electrode assembly 120 in this step is not limited and may be done manually or by machine.

[0035] Install terminal post 160.

[0036] Electrolyte injection: The method of electrolyte injection is not limited; injection from the opening 205 may be selected, or injection by providing an electrolyte injection hole in the end wall 111 may be selected. In this embodiment, it is preferable to inject the electrolyte from the opening 205 and omit the step of providing an electrolyte injection hole in the end wall 111. By directly utilizing the already existing opening 205 for injection, the process can be simplified and costs can be reduced.

[0037] Opening sealing: The cover plate 220 is attached to seal the opening 205. There are several methods for sealing, and they are not limited here. In some embodiments, the outer circumference of the housing 200 is first roll-pressed to form a crimped portion 113 recessed towards the center of the housing 200, thereby restricting the movement of the electrode assembly 120 in the height direction Hd. Then, mechanical sealing technology is employed to upset the cover plate 220 to form a curled edge portion 32, thereby attaching the cover plate 220 to seal the opening 205 of the housing 200. The technology for this step is mature, low-cost, and highly efficient.

[0038] Based on the gradually achieved global consensus on carbon neutrality and further advancements in lithium-ion battery technology, the trend of new energy vehicles replacing conventional fuel-powered vehicles is irreversible. Currently, prismatic batteries cannot be guaranteed not to be destroyed in the event of thermal runaway, which means that drivers and occupants cannot be guaranteed to have sufficient time to evacuate in the event of a safety accident. Cylindrical batteries are the oldest battery shape and have even higher safety characteristics. The inventors have discovered that the safety of cylindrical batteries can be improved by designing several unique structural ratios of cylindrical batteries.

[0039] Referring to Figure 3, the cover plate 220 has an explosion-proof valve 350. A portion of the cover plate 220 surrounded by the explosion-proof valve forms an explosion-proof valve region 222. In some embodiments, the explosion-proof valve 350 may have an annular shape in the top view. In some embodiments, the explosion-proof valve 350 is a notch on the surface of the cover plate 220 facing the electrode assembly 120. The material of the cover plate 220 is preferably steel. Alternatively, it may be any other usable metal material. The surface of the cover plate 220 is nickel-plated to prevent rust and corrosion. However, the nickel plating on the notched portion may be damaged, making the notched portion susceptible to rust and corrosion. If the notch is located on the side of the cover plate 220 opposite the electrode assembly 120 (i.e., outside the secondary battery), the notched portion will be exposed to air, causing the cover plate 220 to corrode. Therefore, by placing the notches on the surface of the cover plate 220 facing the electrode assembly 120, corrosion of the cover plate can be prevented. The explosion-proof valve 350 is used to release pressure by opening the valve in the event of thermal runaway of the battery.

[0040] The winding center hole 120c is located within the orthographic projection range in the height direction Hd of the explosion-proof valve region 222 of the cover plate 220. Compared to other areas of the cover plate 220, the strength of the explosion-proof valve 350 is weaker and more prone to rupture. If thermal runaway occurs in the battery, the high-temperature, high-pressure discharge from inside the battery can cause the explosion-proof valve 350 on the cover plate 220 to collapse and be discharged to the outside of the battery along with the explosion-proof valve region 222 of the cover plate 220, thereby achieving efficient discharge of the discharged material. If thermal runaway occurs in the battery and the explosion-proof valve 350 needs to rupture to release the pressure, it is necessary to use a certain amount of gas thrust to push out the explosion-proof valve region 222 of the explosion-proof valve 350. The winding center hole 120c can be used as a pressure relief channel when releasing pressure from the battery. Since the winding central hole 120c is located within the orthographic projection range of the explosion-proof valve area 222, such gas can provide thrust to the explosion-proof valve area 222 through the winding central hole 120c.

[0041] The diameter of the winding center hole 120c is D1. The diameter of the explosion-proof valve area 222 formed by the explosion-proof valve 350 of the cover plate 220 is D2. D2 may be the diameter measured at the point where the thickness of the cover plate 220 is minimum at the location of the explosion-proof valve 350. In some embodiments, 35% ≥ D1 / D2 ≥ 10%. This ratio design of D1 / D2 allows the ratio of the diameter D1 of the winding center hole 120c to be sufficiently large, thereby providing a sufficiently large pressure relief channel, which is beneficial for gas discharge. If thermal runaway occurs in the battery, it is even more preferable to release the pressure, ensure the integrity of the battery body, and improve the safety of the cylindrical battery 100.

[0042] The housing 200 has an outer diameter D3. In some embodiments, 50% ≤ D2 / D3 ≤ 90%. If ≤ D2 / D3 is greater than 90%, it is difficult to achieve in the manufacturing process. Therefore, D2 / D3 ≤ 90% must be satisfied to ensure the manufacturability of the battery. If D2 / D3 is less than 50%, D2 is excessively small, and the area of ​​the explosion-proof valve region 222 surrounded by the explosion-proof valve 350 is excessively small, which may not be effective in releasing pressure in the event of thermal runaway. By designing the ratio of D2 / D3, in combination with the ratio design of D1 / D2, the pressure relief channel of the cylindrical battery can be optimized, and moreover, both preferable pressure relief and manufacturability can be ensured simultaneously.

[0043] The height of the cylindrical battery 100 is H. Height H refers to the height of the point where the distance from the end wall 111 of the housing 200 to the opposite side of the housing 200 is greatest (in this embodiment, the curled edge portion 32), i.e., the height of the housing 200 (excluding the height of the terminal posts 160). In some embodiments, D2 > D1 ≥ 3%H is satisfied. By setting the lower limit of the diameter D1 of the winding center hole 120c to 3%H and setting D2 to be greater than D1, a winding center hole 120c with a sufficiently large diameter based on the height of the battery is provided as a pressure relief channel, thereby allowing pressure to be released when thermal runaway occurs in the battery.

[0044] In some embodiments, D3 > D2 ≥ 20%H is satisfied. By setting the lower limit of the diameter D2 of the explosion-proof valve region 222 to 20%H and making D3 larger than D2, an area of ​​the explosion-proof valve region 222 with a sufficiently large diameter based on the height of the battery is provided, and pressure can be more preferably released by making it easier to push out the explosion-proof valve region 222 when thermal runaway occurs in the battery.

[0045] In some embodiments, the diameter D1 of the winding center hole 120c is in the range of 4 mm to 8 mm. This range of D1 provides a sufficiently large winding center hole 120c as a pressure relief channel for various types of cylindrical batteries, allowing pressure to be released when thermal runaway occurs in the battery.

[0046] In some embodiments, the diameter D2 of the explosion-proof valve area 222 is in the range of 27 mm to 31 mm. In embodiments in which the cover plate 220 is clamped by a crimped portion 113 and a curled edge portion 32, the range of D2 is the maximum achievable diameter range, based on the placement of the crimped portion 113 and the curled edge portion 32.

[0047] The technical solution of the present invention is compatible with multiple types of cylindrical batteries. In some embodiments, the cylindrical battery 100 is a 46 series cylindrical battery. That is, the outer diameter D3 of the housing 200 is 46 mm, for example, the 4680, 4695, and 46120 cylindrical batteries described above. In some embodiments, the height H of the cylindrical battery 100 is in the range of 80 mm to 160 mm. For example, the height H may be 120 mm, 95 mm, or 80 mm. The technical solution of the present invention can provide a sufficiently large pressure relief channel for multiple types of cylindrical batteries. For example, when the height H is 120 mm, pressure can be more preferably relieved when thermal runaway occurs in the battery, improving the safety of the cylindrical battery 100. Along the height direction of the cylindrical battery, the orthographic projection of the explosion-proof valve area 222 is located entirely within the minimum annulus formed by the curled edge 32. In this way, it can be ensured that the gas is not blocked by the curled edge 32 when thermal runaway occurs in the cylindrical battery, and the pressure can be relieved more quickly.

[0048] In some embodiments, the height H may be in the range of 95 mm to 120 mm. Within this height range, it can be combined with a more suitable explosion-proof valve area 222 with a diameter D2 range of 27 mm to 31 mm, and the diameter D1 can be increased accordingly. As described above, this helps to release pressure and ensure the safety of the cylindrical battery 100.

[0049] Embodiments of the present invention further provide a battery pack 1002 (see Figure 1). The battery pack 1002 includes a cylindrical battery 100 of any embodiment described above, and the battery pack 1002 can have the beneficial effects described with respect to the cylindrical battery 100 described above.

[0050] Embodiments of the present invention further provide an electronic device 1000 (see Figure 1). The electronic device 1000 includes the battery pack 1002 described above, and the electronic device 1000 can have the beneficial effects described above with respect to the cylindrical battery 100 and / or battery pack 1002.

[0051] In some embodiments, the electronic device 1000 is a vehicle, as shown in Figure 1. As described above with reference to Figure 3, the cylindrical battery 100 provided by embodiments of the present invention ensures that the battery body will not be destroyed if thermal runaway occurs in the battery, thereby ensuring that the driver and occupants have sufficient time to evacuate in the event of a safety accident.

[0052] The above describes only preferred embodiments of the present invention and does not limit it. Those skilled in the art will know that the present invention can be modified and adapted in various ways. Modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention are all within the scope of protection of the present invention. [Industrial applicability]

[0053] The cylindrical battery, battery pack, and electronic device of the present invention can improve the safety of at least the cylindrical battery. [Explanation of Symbols]

[0054] D1, D2: Diameter D3: Outer diameter H: Height Hd: Height direction 100: Cylindrical battery 109: Side wall 111: End wall 113: Crimping section 120: Electrode assembly 120c: Winding center hole 121: Tab 1 122: Second Tab 160: Terminal Post 200: Cabinet 205:Aperture 220: Cover plate 222: Explosion-proof valve area 242, 244: Insulating material 301: First current collector plate 302: Second current collector plate 32: Curl edge 350: Explosion-proof valve 1000:Electronic equipment 1001: Vehicle body 1002: Battery pack

Claims

1. It is a cylindrical battery, The cylindrical battery has a housing having an opening at one end in the height direction, An electrode assembly located within the housing and having a winding center hole, A cover plate fitted into the opening of the housing and having an explosion-proof valve region formed by being surrounded by an explosion-proof valve, Includes, The winding central hole is located within the orthographic projection range in the height direction of the explosion-proof valve area of ​​the cover plate. The winding central hole has a diameter D1, the explosion-proof valve region of the cover plate has a diameter D2, and 35% ≥ D1 / D2 ≥ 10%. A cylindrical battery characterized by the following features.

2. The housing has an outer diameter D3, and 50% ≤ D2 / D3 ≤ 90%. A cylindrical battery according to claim 1, characterized in that...

3. The cylindrical battery has a height H, and D2 > D1 ≥ 3%H. A cylindrical battery according to claim 1, characterized in that...

4. The cylindrical battery has a height H, and D3 > D2 ≥ 20%H. A cylindrical battery according to claim 2, characterized in that...

5. The range for D1 is 4 mm to 8 mm. A cylindrical battery according to claim 1, characterized in that...

6. The range for D2 is 27 mm to 31 mm. The range of H is 80 mm to 160 mm. A cylindrical battery according to claim 3, characterized in that...

7. The explosion-proof valve is a notch on the surface of the cover plate facing the electrode assembly, The range of H is 95 mm to 120 mm. A cylindrical battery according to claim 1, characterized in that...

8. A crimped portion protruding inward is provided on the side wall of the housing near the opening, and the side wall has a curled edge portion extending inward on the side of the crimped portion that faces away from the electrode assembly, and the cover plate is sandwiched between the crimped portion and the curled edge portion in the height direction. Along the height direction of the cylindrical battery, the orthographic projection of the explosion-proof valve region is perfectly located within the smallest annulus formed by the curled edge. A cylindrical battery according to claim 1, characterized in that...

9. Includes a cylindrical battery according to any one of claims 1 to 8 A battery pack characterized by the following features.

10. Includes the battery pack described in claim 9 An electronic device characterized by the following features.

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