Cylindrical battery, battery device and electric equipment

Abstract

The utility model discloses a cylindrical battery, a battery device and electric equipment, the cylindrical battery comprises a battery cell, a first collector plate and an explosion-proof valve, the battery cell comprises a body, a first tab layer and a second tab layer, the first tab layer is arranged at one end of the body in the axial direction, and the first tab layer is of a layered structure formed by rubbing a continuous first tab; the second tab layer is arranged at the other end of the body in the axial direction, the second tab layer is of a layered structure formed by flattening a plurality of spaced second tabs, and the polarity of the second tab layer is opposite to that of the first tab layer; the first collector plate is positioned on one side, far away from the battery cell, of the first tab layer and is connected with the first tab; the anti-explosion valve is positioned on one side, far away from the battery cell, of the second tab layer. The first tab layer formed by kneading is arranged at one end of the body, the second tab layer formed by pressing is arranged at the other end of the body, the first tab layer is connected with the first collector plate, and the anti-explosion valve is arranged on one side of the second tab layer, so that power failure and exhaust are timely performed after the battery cell is in thermal runaway, the risk of thermal diffusion is reduced, and the safety of the battery is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of batteries, in particular to a cylindrical battery, a battery device and electrical equipment. Background Art

[0002] The cylindrical battery includes a cylindrical cell, which is formed by winding a negative electrode sheet, a positive electrode sheet and a separator in layers. The tabs of the positive and negative electrode sheets are exposed outside the separator from both axial sides of the cell and are electrically connected to the outside.

[0003] When existing cylindrical batteries experience thermal runaway, the power cannot be cut off in time, the generated gases cannot be discharged in time, the thermal runaway cannot be controlled in time, and may even cause an explosion. Utility Model Content

[0004] The utility model aims to provide a cylindrical battery, a battery device and an electrical device, which can cut off power and exhaust gas in time after the battery core thermal runaway, thereby reducing the risk of heat diffusion.

[0005] In order to achieve the purpose of the utility model, the utility model provides the following technical solutions:

[0006] In a first aspect, the utility model provides a cylindrical battery, comprising a battery cell, a first current collecting disk and an explosion-proof valve, wherein the battery cell comprises a body, a first pole lug layer and a second pole lug layer, wherein the first pole lug layer is arranged at one end of the body in the axial direction, and the first pole lug layer is a layered structure formed by flattening continuous first pole lugs; the second pole lug layer is arranged at the other end of the body in the axial direction, and the second pole lug layer is a layered structure formed by flattening a plurality of spaced second pole lugs, and the polarity of the second pole lug layer is opposite to that of the first pole lug layer; the first current collecting disk is located on a side of the first pole lug layer away from the body, and is connected to the first pole lug layer; the explosion-proof valve is located on a side of the second pole lug layer away from the body.

[0007] In one embodiment, the first current collecting disk is provided with at least one first welding portion, the first welding portion is welded to the first pole tab layer, and / or the first current collecting disk is further provided with at least one wetting groove along the axial direction of the body.

[0008] In one embodiment, the cylindrical battery further includes a second current collecting disk, the second current collecting disk is located between the second pole lug layer and the explosion-proof valve, the second current collecting disk is provided with at least one second welding portion, and the second welding portion is welded to the second pole lug layer.

[0009] In one embodiment, the cylindrical battery further includes a cover plate, the cover plate is located on a side of the second current collecting plate away from the second electrode tab layer, and the explosion-proof valve is disposed on the cover plate.

[0010] In one embodiment, the cover plate is further provided with at least one third welding portion, and the third welding portion is welded to the second current collecting plate.

[0011] In one embodiment, the second collecting plate is further provided with at least one exhaust hole.

[0012] In one embodiment, the thickness of the first current collecting plate is a first thickness D1, and the thickness of the second current collecting plate is a second thickness D2, satisfying: D1 ≥ D2.

[0013] In one implementation, the first thickness D1 satisfies: 0.1 mm ≤ D1 ≤ 0.5 mm, and / or the second thickness D2 satisfies: 0.1 mm ≤ D2 ≤ 0.5 mm.

[0014] In one embodiment, the thickness of the first current collecting disk is a first thickness D1, and the tab compression amount of the first tab layer is W, satisfying: W≥10*D1, wherein the tab compression amount W of the first tab layer is the difference between the height of the first tab before flattening and the height of the first tab after flattening.

[0015] In one embodiment, the tab compression amount W of the first tab layer further satisfies: 1mm≤W≤12mm, wherein the tab compression amount W of the first tab layer is the difference between the height of the first tab before flattening and the height of the first tab after flattening.

[0016] In one embodiment, the thickness of the second current collecting disk is a second thickness D2, and the overlapping thickness of the second pole tab layer is H, satisfying: H≥0.5*D2, wherein the overlapping thickness H of the second pole tab layer is the average thickness of a plurality of the second pole tabs after being flattened.

[0017] In one embodiment, the overlapping thickness H of the second pole tab layer further satisfies: 0.05 mm ≤ H ≤ 0.3 mm, wherein the overlapping thickness H of the second pole tab layer is the average thickness of a plurality of the second pole tabs after being flattened.

[0018] In a second aspect, the utility model further provides a battery device, comprising a housing and a cylindrical battery as described in any one of the various embodiments of the first aspect, wherein the cylindrical battery is accommodated in the housing.

[0019] In a third aspect, the utility model further provides an electrical device, comprising an electrical device and a cylindrical battery as described in any one of the various embodiments of the first aspect or a battery device as described in the second aspect, wherein the battery device or the cylindrical battery supplies power to the electrical device.

[0020] By providing a first pole ear layer formed by flattening at one end of the battery cell body, and a second pole ear layer formed by flattening at the other end, the first pole ear layer is connected to the first current collecting plate on the side away from the battery cell, and an explosion-proof valve is provided on the side of the second pole ear layer away from the battery cell, power can be cut off and exhaust can be carried out in time after thermal runaway of the battery cell, thereby reducing the risk of heat diffusion and improving the safety of the battery. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the implementation methods of the utility model or the technical solutions in the prior art, the drawings required for use in the implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some implementation methods of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0022] Figure 1 is a three-dimensional diagram of a cylindrical battery of an embodiment;

[0023] Figure 2 is a schematic diagram of a first electrode tab of an embodiment;

[0024] Figure 3 is a schematic diagram of a second electrode tab of an embodiment;

[0025] Figure 4 is a schematic diagram of a cover plate of an embodiment;

[0026] Figure 5 is a top view of a cylindrical battery of an embodiment;

[0027] Figure 6 is a bottom view of a cylindrical battery of an embodiment;

[0028] Figure 7 1 is a front view of a cylindrical battery according to an embodiment of the present invention.

[0029] Description of reference numerals:

[0030] 100-cylindrical battery, 10-battery cell, 11-first pole piece, 12-second pole piece, 20-first pole ear layer, 21-first pole ear, 30-second pole ear layer, 31-second pole ear, 40-first current collecting plate, 41-first welding part, 42-wetting groove, 43-center hole, 50-explosion-proof valve, 60-cover plate, 61-third welding part, 70-second current collecting plate, 71-exhaust hole, 72-second welding part;

[0031] D1-first thickness, D2-second thickness. DETAILED DESCRIPTION

[0032] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0033] It should be noted that when a component is said to be "fixed to" another component, it can be directly on the other component or there can be a central component. When a component is said to be "connected to" another component, it can be directly connected to the other component or there can be a central component at the same time.

[0034] Unless otherwise defined, all technical and scientific terms used in this utility model have the same meaning as those commonly understood by technicians in the technical field of this utility model. The terms used in the specification of this utility model are only for the purpose of describing specific embodiments and are not intended to limit this utility model. The term "and / or" used in this utility model includes any and all combinations of one or more related listed items.

[0035] In conjunction with the accompanying drawings, some embodiments of the present invention are described in detail below. In the absence of conflict, the following embodiments and features in the embodiments can be combined with each other.

[0036] The embodiment of the utility model provides an electric device, including an electric device and a battery device in the embodiment of the utility model or a cylindrical battery in the embodiment of the utility model, and the battery device or the cylindrical battery supplies power to the electric device.

[0037] Optionally, the power-consuming device may be an electric vehicle, a hybrid vehicle, a base station, a household power load, an energy storage device, etc. The power-consuming device adopts the battery pack in the embodiment of the utility model, has a low risk of thermal runaway and a high safety factor.

[0038] The embodiment of the utility model further provides a battery device, comprising a housing and a cylindrical battery as in the embodiment of the utility model, wherein the cylindrical battery is accommodated in the housing.

[0039] Optionally, the battery device includes a housing and at least one cylindrical battery. The battery device may be an energy storage battery device, a power battery device, etc., without limitation.

[0040] Optionally, the shell is made of a material with high structural strength, specifically metal materials, high-strength plastics, ceramics, etc. The metal materials include aluminum, aluminum alloy, magnesium alloy, iron and iron alloy, etc.

[0041] Optionally, the shell includes an upper shell and a lower shell, and the upper shell and the lower shell are spliced ​​to form the shell of the battery pack. The upper shell and the lower shell can be connected and fixed by welding, bonding, snapping, screwing, etc., without specific limitation.

[0042] Optionally, the cylindrical battery is housed in a housing of the battery device, and the battery may be a cylindrical wound battery.

[0043] Optionally, the number of cylindrical batteries can be one or more, such as two, three, four, etc., and the multiple cylindrical batteries are electrically connected, without specific limitation.

[0044] The battery device in the embodiment of the utility model adopts the cylindrical battery in the embodiment of the utility model, which can reduce the risk of heat diffusion after thermal runaway and improve the safety factor.

[0045] The cylindrical battery in the embodiment of the utility model is described in detail below.

[0046] Please refer to Figure 1 In an embodiment of the utility model, a cylindrical battery 100 is provided, comprising a battery cell 10 , a first current collecting plate 40 and an explosion-proof valve 50 .

[0047] First define the direction. Figure 2 As shown, X is a first direction, and Y is a second direction. The first direction X is an extending direction of the axis of the battery cell 10 , and the second direction Y is a winding direction of the battery cell 10 .

[0048] Optionally, the battery cell 10 includes a body, a first tab layer 20 and a second tab layer 30 , wherein the first tab layer is disposed at one end of the body in the axial direction, and the axial direction of the body is the first direction X. The first tab layer 20 is a layered structure formed by flattening continuous first tabs 21 .

[0049] The second pole tab layer 30 is connected to the other end of the body in the axial direction. The second pole tab layer 30 is a layered structure formed by flattening a plurality of spaced second pole tabs 31 . The second pole tab layer 30 and the first pole tab layer 20 have opposite polarities.

[0050] Optionally, the battery cell 10 is formed by winding a negative electrode sheet, a separator and a positive electrode sheet stacked in sequence along the second direction Y, wherein the number of the negative electrode sheet, the separator and the positive electrode sheet is at least one, and there is no specific limitation.

[0051] Optionally, the positive electrode sheet and the negative electrode sheet are commonly used in the art, and there is no specific limitation.

[0052] Optional, such as Figure 2As shown, the first pole ear 21 is connected to the first pole piece 11, and the first pole piece 11 can be a positive pole piece or a negative pole piece, without limitation. The first pole ear 21 is exposed at one end of the first pole piece 11 in the first direction X. The first pole ear 21 and the first pole piece 11 can be an integrated structure, that is, the first pole ear 21 is the part of the first pole piece 11 extending out of the diaphragm; or, the first pole ear 21 is a foil (aluminum foil, copper foil, etc.), and the first pole ear 21 and the first pole piece 11 are connected by welding, bonding, clamping, screwing, etc.

[0053] Optionally, the first pole ear layer 20 is a planar layered structure formed by physically extruding and flattening the first pole ear 21 through a conical head, and the planar shape may be circular, square, polygonal, etc., without specific limitation.

[0054] Optional, such as Figure 3 As shown, the second pole ear 31 is connected to the second pole piece 12, and the polarity of the second pole piece 12 is opposite to that of the first pole piece 11, and there is no specific limitation. The second pole ear 31 is exposed at the other end of the second pole piece 12 in the first direction X. Similar to the first pole ear 21, the second pole ear 31 and the second pole piece 12 can be an integrated structure, and the portion of the second pole piece 12 that exceeds the diaphragm is die-cut to form a plurality of second pole ears 31 arranged at intervals; or, the plurality of second pole ears 31 are formed by die-cutting a foil (aluminum foil, copper foil, etc.), and the second pole ear 31 and the second pole piece 12 are connected by welding, bonding, clamping, screwing, etc.

[0055] Optionally, the second electrode tab layer 30 is a planar layered structure formed by flattening or pressing a plurality of second electrode tabs 31 , and the planar shape may be circular, square, polygonal, etc., without specific limitation.

[0056] Optionally, the distance between the second pole ear 31 near the head end of the second pole piece 12 and the head end edge of the second pole piece 12 is greater than the distance between the second pole ear 31 near the tail end of the second pole piece 12 and the tail end edge of the second pole piece 12. The head section and tail end of the second pole piece 12 refer to the direction from the head end edge to the tail end edge of the second pole piece 12 when the second pole piece 12 is wound along the second direction Y. The second pole ear 31 near the head end of the second pole piece 12 is spaced from the head end edge of the second pole piece 12, which can prevent the second pole ear 31 from blocking the center hole after the second pole piece 12 is wound, thereby reducing the air permeability.

[0057] Optionally, the cylindrical battery 100 further includes a shell (not shown in the figure), the shell includes side plates, the side plates enclose a cylindrical accommodating cavity, and the battery cell 10, the first pole tab layer 20, the second pole tab layer 30 and the first collecting disk 40 are accommodated in the accommodating cavity.

[0058] Optional, such as Figure 4 and Figure 7As shown, the housing further includes a cover plate 60, which is connected to the opening of the housing to close the accommodating cavity.

[0059] Optionally, there are two cover plates 60, and the two cover plates 60 respectively seal the two ends of the accommodating cavity along the first direction X. The connection method of the cover plate 60 and the side plate can be welding, bonding, clamping, screwing, etc., which is not specifically limited.

[0060] Optionally, the shell is made of a material with high structural strength, specifically metal materials, high-strength plastics, ceramics, etc., and metal materials are aluminum, aluminum alloys, magnesium alloys, iron and iron alloys, etc. The shell can be an integrated structure, that is, the bottom plate and the side plates are an integrated structure made by an integrated molding process, and the integrated molding process can be specifically stamping, casting, etc., without limitation.

[0061] Optionally, the housing may be a split structure, and the side panels and the bottom panel may be connected and fixed by welding, bonding, clamping, screwing, etc. The wall thickness of the housing may be substantially uniform, that is, the thickness of the side panels may be substantially uniform, and the thickness of the bottom panel and the side panels may also be substantially the same.

[0062] Optionally, the first current collecting disk 40 is located on a side of the first pole tab layer 20 away from the battery cell 10 , and is connected to the first pole tab layer 20 .

[0063] Optionally, the material of the first current collecting plate 40 may be copper, aluminum, etc., and the shape of the first current collecting plate 40 may be circular, square, polygonal, etc., without limitation.

[0064] Optionally, the first current collecting plate 40 and the first electrode tab layer 20 may be connected by welding, bonding, clamping, screwing, etc.

[0065] Optionally, the explosion-proof valve 50 is located on a side of the second electrode tab layer 30 away from the battery cell 10 .

[0066] Optionally, the explosion-proof valve 50 is a commonly used explosion-proof valve 50 in the art. The explosion-proof valve 50 can be arranged on the cover plate 60 of the cylindrical battery 100, or can be arranged between the side of the second pole ear layer 30 away from the battery cell 10 and the cover plate 60, without specific limitation.

[0067] The existing flattened battery cells have flattened tabs at both ends, which makes exhaust difficult. When the battery cell loses control, exhaust is not smooth, which may cause the shell to bulge and cause high-voltage short circuit, or the shell to explode and cause heat diffusion. At the same time, the metal shavings in the flattened battery cells are not easy to remove, resulting in a high self-discharge rate in the later stage of the battery, and even the risk of internal short circuit.

[0068] The existing flattened battery cells have both ends of the tabs flattened. Since the tabs are folded to form a plane, when the battery cell loses control and produces a large amount of gas, the battery cell has room to move under axial force, and the electrical connection is not easily interrupted, and thermal runaway cannot be controlled. As the runaway temperature rises to the point where smoke ignites, there is also the risk of fire and explosion.

[0069] In the cylindrical battery 100 of the embodiment of the utility model, the first pole tab layer 20 adopts a flattened pole tab forming method, which can reduce the activity space of the first pole tab 21 in the first direction X of the battery cell 10. After high-speed flattening, the first pole tab 21 undergoes plastic deformation and adheres together to form a stable dense structure, namely the first pole tab layer 20. When the battery cell has thermal runaway, the first pole tab layer 20 is not easily deformed by force, so that the first current collector 40 is forced to interrupt the connection welding point with the first pole tab layer 20, and acts as a fuse when the battery cell is out of control, which can disconnect the electrical connection and prevent the battery cell 10 from further thermal runaway.

[0070] The second pole tab layer 30 is formed by die-cutting and flattening the pole tabs, and there are intervals between the plurality of second pole tabs 31 formed by die-cutting. Afterwards, the plurality of second pole tabs 31 are flattened by a flat plate, and there is no adhesion between the plurality of second pole tabs 31, which can increase the uncontrolled exhaust rate of the battery cell 10, so that the smoke quickly gathers to the side of the explosion-proof valve 50. When the pressure exceeds a certain value, the explosion-proof valve 50 is passively opened to discharge the gas out of the shell to avoid further explosion.

[0071] The cylindrical battery 100 in the embodiment of the utility model is provided with a first pole ear layer 20 formed by flattening at one end of the body, and a second pole ear layer 30 formed by flattening at the other end. The first pole ear layer 20 is connected to the first current collecting plate 40 on the side away from the battery cell 10, and an explosion-proof valve 50 is provided on the side of the second pole ear layer 30 away from the battery cell 10. After the battery cell has thermal runaway, power can be cut off and exhaust can be carried out in time, thereby reducing the risk of heat diffusion and improving the safety of the battery.

[0072] Optional, such as Figure 5 As shown, the first current collecting disc 40 is provided with at least one first welding portion 41 , the first welding portion 41 is connected to the first pole tab layer 20 , and / or the first current collecting disc 40 is further provided with at least one wetting groove 42 along the axial direction of the body.

[0073] Optionally, the first welding portion 41 is connected to a side of the first current collecting plate 40 facing the first electrode tab layer 20 . The shape of the first welding portion 41 is not particularly limited and may be square, circular, polygonal, or the like.

[0074] Optionally, the first collecting plate 40 further includes a central hole 43 .

[0075] Optionally, when the battery cell 10 expands, it will squeeze the first current collecting plate 40 along the first direction X, thereby causing the first current collecting plate 40 to deform. The first welding portion 41 is provided with a wetting groove 42 , which has a relatively low strength and is more likely to break when the battery cell 10 expands.

[0076] Optionally, the specific shape of the wetting groove 42 is not limited.

[0077] The first current collecting disc 40 is provided with a first welding portion 41, which is connected to the first pole lug layer 20. The first current collecting disc 40 is also provided with a wetting groove 42. The strength at the wetting groove 42 is relatively small. When the battery cell 10 is expanded and squeezed, the wetting groove 42 is prone to breakage. It can act as a fuse in the event of thermal runaway, cut off power in time, and improve the safety of the battery.

[0078] Optional, such as Figure 6 As shown, the cylindrical battery 100 further includes a second current collecting plate 70 , which is located between the second pole tab layer 30 and the explosion-proof valve 50 . The second current collecting plate 70 is provided with at least one second welding portion 72 , and the second welding portion 72 is connected to the second pole tab layer 30 .

[0079] Optionally, the material and shape of the second current collecting plate 70 are similar to those of the first current collecting plate 40 , which can be referred to without further description.

[0080] Optionally, the second welding portion 72 is at least a portion of the second current collecting plate 70. The shape of the second welding portion 72 is not specifically limited and may be square, circular, polygonal, etc. For example, Figure 6 As shown, the second welding portion 72 is in the shape of a circular ring.

[0081] Optionally, the second electrode tab layer 30 and the second welding portion 72 may be connected by welding, bonding, clamping, etc., which is not specifically limited.

[0082] By configuring the cylindrical battery 100 to further include the second current collecting plate 70 , the second electrode tab layer 30 is connected to the second welding portion 72 of the second current collecting plate 70 , and the connection is stable.

[0083] Optional, such as Figure 4 As shown, the cylindrical battery 100 further includes a cover plate 60 , which is located on a side of the second current collecting plate 70 away from the second electrode tab layer 30 , and the explosion-proof valve 50 is disposed on the cover plate 60 .

[0084] Optionally, the explosion-proof valve 50 may be an explosion-proof valve 50 commonly used in the art, such as a piston spring explosion-proof valve 50, a ejector pin explosion-proof valve 50, etc., without specific limitation.

[0085] Optionally, the explosion-proof valve 50 and the cover plate 60 may be connected by welding, bonding, clamping, screwing, etc., without specific limitation.

[0086] By arranging the explosion-proof valve 50 on the cover plate 60 on the side of the second tab layer 30 away from the body, when a certain pressure is exceeded, the explosion-proof valve 50 passively opens to discharge gas, which can prevent heat diffusion of the battery cell 10 and improve battery safety.

[0087] Optionally, the cover plate 60 is further provided with at least one third welding portion 61 , and the third welding portion 61 is welded to the second current collecting plate 70 .

[0088] Optionally, the number of the third welding portion 61 may be one or more, and the plurality of third welding portions 61 are arranged at intervals, without any specific limitation.

[0089] By arranging the third welding portion 61 of the cover plate 60 to be welded to the second current collecting plate 70 , the connection is stable and the processing is convenient.

[0090] Optionally, the second current collecting plate 70 is further provided with at least one exhaust hole 71, and the specific shape of the exhaust hole 71 is not limited. When thermal runaway occurs in the battery cell 10, the gas can be discharged from the exhaust hole 71 and then discharged from the cylindrical battery 100 through the explosion-proof valve 50, which can reduce the risk of heat diffusion after thermal runaway and improve the safety of the battery.

[0091] Optional, such as Figure 7 As shown, the thickness of the first current collecting plate 40 is a first thickness D1, and the thickness of the second current collecting plate 70 is a second thickness D2, satisfying: D1 ≥ D2.

[0092] Optionally, the first current collecting disc 40 is connected to the first pole lug layer 20 formed by flattening. The first pole lug layer 20 needs to withstand more mechanical stress and vibration when flattened, so a larger thickness is required to ensure its mechanical stability. The second current collecting disc 70 is connected to the second pole lug layer 30 formed by flattening after die cutting. The second pole lug layer 30 does not need to withstand such a large mechanical stress, so the thickness of the second pole lug layer 30 is relatively small. In order to facilitate and stabilize welding, the thickness of the current collecting disc is usually kept roughly the same as the thickness of the pole lug layer. Therefore, the first thickness D1 of the first current collecting disc 40 should be greater than or equal to the second thickness D2 of the second current collecting disc 70.

[0093] By setting the first thickness D1 of the first current collecting disk 40 and the second thickness D2 of the second current collecting disk 70 to satisfy D1 ≥ D2 , the mechanical stability of the connection of the cylindrical battery 100 can be improved.

[0094] Optionally, the first thickness D1 satisfies: 0.1 mm≤D1≤0.5 mm, and / or the second thickness D2 satisfies: 0.1 mm≤D2≤0.5 mm.

[0095] Optionally, the first thickness D1 satisfies: 0.2 mm≤D1≤0.4 mm.

[0096] Optionally, the value of the first thickness D1 may be 0.2 mm, 0.3 mm, 0.35 mm, etc., without specific limitation.

[0097] Optionally, the second thickness D2 satisfies: 0.2 mm≤D2≤0.4 mm.

[0098] Optionally, the value of the second thickness D2 may be 0.2 mm, 0.3 mm, 0.35 mm, etc., without specific limitation.

[0099] The thickness of the collector plate affects its conductivity. A thicker collector plate can provide a larger conductive cross-sectional area, thereby improving the efficiency of current transmission. In addition, it can reduce the interface reaction of the electrode material and reduce the resistance inside the battery, thereby increasing the cycle life of the battery. However, if the thickness of the collector plate is too large, it may affect the heat conduction inside the battery, making heat management difficult and increasing the risk of battery overheating and safety.

[0100] By setting the first thickness D1 to satisfy 0.1 mm≤D1≤0.5 mm, and / or the second thickness D2 to satisfy 0.1 mm≤D2≤0.5 mm, the conductivity of the battery can be improved as much as possible while ensuring the safety of the battery.

[0101] Optionally, the tab compression amount of the first tab layer 20 is W, satisfying: W≥10*D1, wherein the tab compression amount W of the first tab layer 20 is the difference between the height of the first tab 21 before flattening and the height of the first tab 21 after flattening.

[0102] The compression of the flattened end tab refers to the compression of the tab in the length direction after the electrode material is flattened during the manufacturing process of the battery. The size of this compression has a certain impact on the performance and safety of the battery. If the compression is too small, the density of the first tab layer 20 is not enough, which may increase the internal resistance of the battery, increase the heat generation of the battery, and affect the safety and stability of the battery. If the compression is too large, the capacity of the battery may decrease, which may reduce the battery's endurance.

[0103] Therefore, choosing the appropriate amount of tab compression can enhance the structural strength of the battery, increase the battery energy density, reduce the battery internal resistance, and improve the battery's charge and discharge performance.

[0104] By setting the tab compression amount of the first tab layer 20 to W and satisfying: W≥10*D1, the requirement on the flattening and compacting degree of the first tab layer 20 can be met, thereby improving battery performance and reducing use risks.

[0105] Optionally, the tab compression amount W of the first tab layer 20 also satisfies: 1 mm≤W≤12 mm.

[0106] Optionally, the tab compression amount W of the first tab layer 20 satisfies: 2 mm ≤ D1 ≤ 10 mm.

[0107] Optionally, the value of the tab compression amount W of the first tab layer 20 may be 2 mm, 3 mm, 3.5 mm, etc., without specific limitation.

[0108] By setting the tab compression amount W of the first tab layer 20 to satisfy: 1mm≤W≤12mm, the requirement on the flattening and compacting degree of the first tab layer 20 can be met, thereby improving battery performance and reducing use risks.

[0109] Optionally, the overlapping thickness of the second pole tab layer 30 is H, satisfying: H≥0.5*D2, wherein the overlapping thickness H of the second pole tab layer 30 is the average thickness of the plurality of second pole tabs 31 after being wound and flattened.

[0110] Optionally, the overlapping thickness of the flattened end tabs refers to the thickness of the overlapping portion between the two second tabs 31 after the electrode material is flattened during the manufacturing process of the battery.

[0111] By setting the overlapping thickness H of the second tab layer 30 to satisfy H≥0.5*D2, the difficulty of exhaust can be reduced and the battery safety performance can be improved.

[0112] Optionally, the overlapping thickness H of the second tab layer 30 also satisfies: 0.05 mm≤H≤0.3 mm.

[0113] Optionally, the overlapping thickness H of the second tab layer 30 satisfies: 0.08 mm≤H≤0.3 mm.

[0114] Optionally, the overlapping thickness H of the second tab layer 30 may be 0.08 mm, 0.12 mm, 0.2 mm, etc., and H≥0.5*D2 may be satisfied, and there is no specific limitation.

[0115] The overlapping thickness of the flattened end tabs refers to the thickness of the overlapping portion between the two second tabs after the electrode material is flattened during the manufacturing process of the battery. The size of this thickness has a certain impact on the performance and safety of the battery. If the overlapping thickness is too small, it may cause uneven current density distribution of the battery, resulting in reduced charging and discharging performance of the battery. If the overlapping thickness is too large, it may cause difficulty in battery exhaust and increase the risk of thermal runaway.

[0116] By setting the overlapping thickness H of the second tab layer 30 to satisfy 0.05 mm ≤ H ≤ 0.3 mm, the difficulty of exhaust can be reduced and the safety and stability of the battery can be improved.

[0117] In the description of the embodiments of the present invention, it should be noted that the orientation or positional relationship of terms such as "center", "up", "down", "left", "right", "vertical", "horizontal", "inside" and "outside" are based on the orientation or positional relationship described in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0118] The above disclosure is only a preferred embodiment of the present invention, and certainly cannot be used to limit the scope of rights of the present invention. Ordinary technicians in this field can understand that all or part of the processes of the above embodiment and equivalent changes made according to the claims of the present invention still fall within the scope covered by the present invention.

Claims

1. A cylindrical battery, characterized in that: include: A battery cell, comprising a body, a first pole tab layer, and a second pole tab layer, wherein the first pole tab layer is arranged at one end of the body in the axial direction, and the first pole tab layer is a layered structure formed by flattening continuous first pole tabs; the second pole tab layer is arranged at the other end of the body in the axial direction, and the second pole tab layer is a layered structure formed by flattening a plurality of spaced second pole tabs, and the second pole tab layer and the first pole tab layer have opposite polarities; A first current collecting disk is located on a side of the first pole lug layer away from the body and is electrically connected to the first pole lug layer; The explosion-proof valve is located on a side of the second electrode tab layer away from the body.

2. The cylindrical battery according to claim 1, characterized in that: The first current collecting disk is provided with at least one first welding portion, the first welding portion is welded to the first pole tab layer, and / or the first current collecting disk is further provided with at least one wetting groove along the axial direction of the body.

3. The cylindrical battery according to claim 1, characterized in that: The cylindrical battery further includes a second current collecting disk, the second current collecting disk is located between the second pole tab layer and the explosion-proof valve, the second current collecting disk is provided with at least one second welding portion, and the second welding portion is welded to the second pole tab layer.

4. The cylindrical battery according to claim 3, characterized in that: The cylindrical battery further includes a cover plate, which is located on a side of the second current collecting plate away from the second electrode tab layer, and the explosion-proof valve is arranged on the cover plate.

5. The cylindrical battery according to claim 4, characterized in that: The cover plate is further provided with at least one third welding portion, and the third welding portion is welded to the second current collecting plate.

6. The cylindrical battery according to claim 3, characterized in that: The second collecting plate is also provided with at least one exhaust hole.

7. The cylindrical battery according to claim 3, characterized in that: The thickness of the first current collecting plate is a first thickness D1, and the thickness of the second current collecting plate is a second thickness D2, satisfying: D1 ≥ D2.

8. The cylindrical battery according to claim 7, characterized in that: The first thickness D1 satisfies: 0.1 mm ≤ D1 ≤ 0.5 mm, and / or the second thickness D2 satisfies: 0.1 mm ≤ D2 ≤ 0.5 mm.

9. The cylindrical battery according to claim 1, characterized in that: The thickness of the first current collecting disk is a first thickness D1, and the tab compression amount of the first tab layer is W, satisfying: W≥10*D1, The tab compression amount W of the first tab layer is the difference between the height of the first tab before flattening and the height of the first tab after flattening.

10. The cylindrical battery according to claim 1, characterized in that: The tab compression amount W of the first tab layer satisfies: 1mm≤W≤12mm, The tab compression amount W of the first tab layer is the difference between the height of the first tab before flattening and the height of the first tab after flattening.

11. The cylindrical battery according to claim 3, characterized in that: The thickness of the second current collecting plate is a second thickness D2, and the overlapping thickness of the second tab layer is H, which satisfies: H≥0.5*D2, The overlapping thickness H of the second pole tab layer is the average thickness of the plurality of second pole tabs after being flattened.

12. The cylindrical battery according to claim 1, characterized in that: The overlapping thickness H of the second tab layer satisfies: 0.05mm≤H≤0.3mm, The overlapping thickness H of the second pole tab layer is the average thickness of the plurality of second pole tabs after being flattened.

13. A battery device, characterized in that: The invention comprises a shell and a cylindrical battery as claimed in any one of claims 1 to 12, wherein the cylindrical battery is accommodated in the shell.

14. An electrical device, characterized in that: It comprises an electric device and a cylindrical battery as claimed in any one of claims 1 to 12 or a battery device as claimed in claim 13, wherein the battery device or the cylindrical battery is used to supply power to the electric device.

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