Cylindrical battery, battery pack and electric equipment

Abstract

The utility model provides a cylindrical battery, a battery pack and electric equipment, and belongs to the technical field of secondary batteries. The cylindrical battery comprises a shell, a naked battery cell, a positive collector plate, an insulating sealing piece and an electrode terminal, the naked battery cell and the positive collector plate are both mounted in the shell, and the positive collector plate is arranged at one end of the naked battery cell. The insulation sealing piece is connected to the positive current collecting plate, and at least part of the insulation sealing piece is located between the positive current collecting plate and the shell, so that the positive current collecting plate and the shell are insulated and isolated. And the electrode terminal penetrates through the insulating sealing piece and is connected to the positive collector plate. According to the cylindrical battery, a connecting part for connecting the electrode terminal and the positive collector plate as well as a sealing part and an insulating part which are required in the connecting process of the electrode terminal and the positive collector plate are omitted, so that the number of parts required by the cylindrical battery is small, and the connection relationship among the parts of the cylindrical battery is simple; therefore, the design structure of the cylindrical battery is more simplified, the design weight of the cylindrical battery is reduced, and the lightweight design of the cylindrical battery is further facilitated.

Description

Technical Field

[0001] Embodiments of the present application relate to the technical field of secondary batteries, and particularly to a cylindrical battery, a battery pack, and an electrical device. Background Art

[0002] The cylindrical battery is a common lithium-ion battery. Most of the existing cylindrical batteries use methods such as riveting and threaded connection between the electrode terminal and the bare battery cell.

[0003] In order to ensure that the connection between the electrode terminal and the bare battery cell meets the safety performance requirements of the lithium-ion battery, the existing connection structure is relatively complex, making the design weight of the cylindrical battery relatively large, which is not conducive to the lightweight design of the cylindrical battery. Utility Model Content

[0004] The present application provides a cylindrical battery, a battery pack, and an electrical device, which can simplify the design structure of the cylindrical battery.

[0005] In a first aspect, the present application provides a cylindrical battery, including a housing, a bare battery cell, a positive current collector plate, an insulating seal, and an electrode terminal. The bare battery cell and the positive current collector plate are both installed in the housing, and the positive current collector plate is disposed at one end of the bare battery cell. The insulating seal is at least partially located between the positive current collector plate and the housing to insulate and isolate the positive current collector plate from the housing. The electrode terminal passes through the insulating seal and is connected to the positive current collector plate.

[0006] Through the above solution, since the electrode terminal passes through the insulating seal and is connected to the positive current collector plate, the connecting components for connecting the electrode terminal and the positive current collector plate, as well as the sealing components and insulating components required during the connection process between the electrode terminal and the positive current collector plate, are omitted, so that the number of components required for the cylindrical battery is small, and the connection relationship between the components of the cylindrical battery is simple, thereby making the design structure of the cylindrical battery more simplified, reducing the design weight of the cylindrical battery, and further being conducive to the lightweight design of the cylindrical battery.

[0007] In a possible design, the electrode terminal passes through the insulating seal and is connected to the positive current collector plate in a self-piercing riveting structure.

[0008] Through the above solution, the self-piercing riveting structure can form a firm connection relationship between the electrode terminal, the insulating seal, and the positive current collector plate through a simple connection structure, so that the electrode terminal, the insulating seal, and the positive current collector plate form a stable structural whole, and further can simplify the design structure of the cylindrical battery.

[0009] In a possible design, the insulating seal is integrally injection-molded with the positive current collector plate.

[0010] Through the above solution, the insulating seal and the positive current collector plate are combined into one component, which can further reduce the number of components of the cylindrical battery, and further simplify the design structure of the cylindrical battery.

[0011] In a possible design, the positive current collector plate includes a connecting portion and a current collecting portion that are connected to each other. The thickness of the connecting portion is greater than the thickness of the current collecting portion. The current collecting portion is connected to the positive electrode tab of the bare battery cell, and the electrode terminal is connected to the connecting portion.

[0012] Through the above solution, the greater thickness of the connecting portion than that of the current collecting portion can make the strength of the connecting portion greater than that of the current collecting portion. During the connection process between the electrode terminal and the connecting portion, the possibility of the electrode terminal penetrating the connecting portion is small, which is convenient for the operator to select the connection method and connection force between the electrode terminal and the connecting portion, thus facilitating the connection between the electrode terminal and the connecting portion. In addition, when the electrode terminal passes through the insulating seal and is connected to the positive current collector plate in a self-piercing riveting structure, the above setting form can ensure good connection strength between the electrode terminal and the connecting portion while reducing the risk of the electrode terminal penetrating the connection, so as to avoid faults such as electrolyte leakage in the cylindrical battery, thereby keeping the cylindrical battery in a good working state.

[0013] In a possible design, the thickness of the connecting portion is at least twice the thickness of the current collecting portion.

[0014] Through the above solution, it is convenient for the connection between the electrode terminal and the connecting portion. In addition, when the electrode terminal passes through the insulating seal and is connected to the positive current collector plate in a self-piercing riveting structure, the above setting form can ensure good connection strength between the electrode terminal and the connecting portion while further reducing the risk of the electrode terminal penetrating the connection, so as to avoid faults such as electrolyte leakage in the cylindrical battery, thereby keeping the cylindrical battery in a good working state.

[0015] In a possible design, the cylindrical battery further includes a first seal. The housing includes a cylindrical body and a cover plate, and the cover plate is provided at one end of the bare battery cell away from the positive current collector plate. The first seal is provided between the cover plate and the cylindrical body to achieve the sealed connection between the cover plate and the cylindrical body. Or, the housing includes a cylindrical body and a cover plate, the cover plate is provided at one end of the bare battery cell away from the positive current collector plate, and the cover plate is welded to the cylindrical body to achieve the sealed connection between the cover plate and the cylindrical body.

[0016] Through the above solution, the cylindrical body is mainly used to accommodate the internal components of the cylindrical battery including the bare battery cell, and can also provide a protective effect on the internal components of the cylindrical battery. The cover plate is usually used in combination with the cylindrical body so that the cover plate and the cylindrical body together form the housing, and the cover plate can play a role in fixing and sealing the cylindrical body. The first seal can be arranged between the cover plate and the cylindrical body by means of sealant bonding. This method has a low operation difficulty and can improve the sealing effect of the first seal, so as to keep the overall cylindrical battery in a stable working state.

[0017] In a possible design, an explosion-proof structure is provided on the cover plate.

[0018] With the above solution, when a safety failure occurs in the cylindrical battery, such as overcharging, over-discharging, out-of-control electrochemical reaction, external short circuit, etc., a large amount of gas will be generated inside the cylindrical battery, resulting in an increase in the internal pressure of the cylindrical battery. When the pressure reaches the threshold, the explosion-proof structure on the cover plate will release the excess gas inside the cylindrical battery to balance the pressure difference between the inside and outside of the cylindrical battery, thereby reducing the risk of safety accidents such as explosion caused by excessive internal pressure of the cylindrical battery, and further improving the safety performance of the cylindrical battery.

[0019] In a possible design, the explosion-proof structure is configured as an explosion-proof score line, an explosion-proof film or a pressure relief valve.

[0020] With the above solution, the above explosion-proof structure can form a channel communicating with the outside when the cylindrical battery undergoes thermal runaway, connecting the internal and external spaces of the cylindrical battery, enabling the substances inside the shell to be released directionally, balancing the pressure inside and outside the cylindrical battery, thereby reducing the risk of safety accidents such as explosion caused by excessive internal pressure of the cylindrical battery, so as to improve the safety performance of the cylindrical battery.

[0021] In a second aspect, the present invention provides a battery pack including the cylindrical battery of the first aspect.

[0022] For the cylindrical battery provided in the above second aspect and each possible design of the second aspect, the beneficial effects can be referred to the beneficial effects brought by the above first aspect and each possible implementation manner of the first aspect, which will not be elaborated here.

[0023] In a third aspect, the present invention provides an electrical equipment including the battery pack of the second aspect.

[0024] For the electrical equipment provided in the above third aspect and each possible design of the third aspect, the beneficial effects can be referred to the beneficial effects brought by the above first aspect and each possible implementation manner of the first aspect, which will not be elaborated here.

[0025] In summary, the cylindrical battery only includes a shell, a bare battery cell, a positive current collector plate and an electrode terminal, and the number of required components is small. And the bare battery cell and the positive current collector plate are both installed inside the shell, the positive current collector plate is arranged at one end of the bare battery cell, the insulating seal is connected to the positive current collector plate, and the electrode terminal passes through the insulating seal and is connected to the positive current collector plate, making the connection relationship between the components of the cylindrical battery simple, thus simplifying the design structure of the cylindrical battery to reduce the design weight of the cylindrical battery, which is conducive to the lightweight design of the cylindrical battery. Description of the Drawings

[0026] Figure 1Schematic diagram of the overall structure of a cylindrical battery provided by an embodiment of the present application.

[0027] Figure 2 Schematic cross-sectional view of a cylindrical battery provided by an embodiment of the present application.

[0028] Figure 3 For Figure 2 Partial enlarged view at location A in

[0029] Figure 4 Schematic cross-sectional view of a positive current collector plate provided by an embodiment of the present application.

[0030] Figure 5 For Figure 2 Partial enlarged view at location B in

[0031] Figure 6 Schematic diagram of the structure of a cover plate provided by an embodiment of the present application.

[0032] Figure 7 For Figure 2 Partial enlarged view at location C in

[0033] Reference numerals in the drawings: 1, cylindrical battery; 11, housing; 111, cylinder; 112, cover plate; 1121, explosion-proof structure; 1122, liquid injection hole; 12, bare battery cell; 13, positive current collector plate; 131, connection part; 132, current collection part; 14, insulating seal; 15, electrode terminal; 16, first seal; 17, second seal. Detailed implementation manners

[0034] To make the objectives, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present application. Apparently, the described embodiments are some, but not all, of the embodiments of the present application. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present application without creative efforts shall fall within the scope of protection of the present application.

[0035] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which this application belongs; the terms used in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" and any variations thereof in the specification and claims of this application and the drawings are intended to cover non-exclusive inclusion.

[0036] References to "embodiments" in this disclosure mean that the particular features, structures, or characteristics described in connection with the embodiments can be included in at least one embodiment of the present application. The phrase "embodiment" appearing in various places in the specification is not necessarily referring to the same embodiment, nor is it an independent or alternative embodiment mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0037] As used herein, the term "and / or" is merely a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent three situations: the existence of A, the coexistence of A and B, and the existence of B. Additionally, the character " / " herein generally represents an "or" relationship between the associated objects before and after.

[0038] The orientation terms appearing in the following description are all the directions shown in the figures, and do not specifically limit the structure of the current-limiting module of the present application. For example, in the description of the present application, terms such as "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings. This is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation to the present application.

[0039] Furthermore, terms such as "first", "second", etc. in the specification and claims of the present application or in the above-mentioned drawings are used to distinguish different objects, rather than to describe a specific order, and may explicitly or implicitly include one or more of such features.

[0040] In the description of the present application, unless otherwise specified, "a plurality of" means two or more (including two). Similarly, "a plurality of groups" means two or more groups (including two groups).

[0041] In the description of the present application, it should be noted that unless otherwise clearly specified and defined, the terms "installed", "connected", and "coupled" should be understood in a broad sense. For example, the "connection" or "coupling" of mechanical structures may refer to a physical connection. For example, a physical connection may be a fixed connection, such as a fixed connection through a spacer, such as a fixed connection through screws, bolts, or other spacers; a physical connection may also be a detachable connection, such as a snap connection or a snap-fit connection; a physical connection may also be an integral connection, such as a connection formed by welding, bonding, or integral molding. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to specific circumstances. The "connection" or "coupling" of circuit structures may refer to not only a physical connection but also an electrical connection or a signal connection. For example, it may be a direct connection, that is, a physical connection, or it may be indirectly connected through at least one intermediate element, as long as the circuit is connected. It may also be the communication inside two elements; in addition to the signal connection through the circuit, the signal connection may also refer to the signal connection through a media medium, such as radio waves. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to specific circumstances.

[0042] The present application discloses a bare battery cell, a battery module, a battery, and an electrical device. The battery module includes the bare battery cell. The electrical device includes the battery or the battery module and can be powered by the battery or the battery module. Among them, the electrical device may be a vehicle, a mobile phone, a portable device, a laptop computer, a ship, a spacecraft, an electric toy, an electric tool, an energy storage device, a amusement device, an elevator, a lifting device, and so on. The vehicle may be a fuel vehicle, a gas vehicle, or a new energy vehicle. The new energy vehicle may be a pure electric vehicle, a hybrid electric vehicle, or an extended-range electric vehicle, etc.; the spacecraft includes an airplane, a rocket, a space shuttle, a spaceship, and so on; the electric toy includes a fixed or mobile electric toy, such as a game console, an electric vehicle toy, an electric ship toy, or an electric airplane toy, etc.; the electric tool includes a metal cutting electric tool, a grinding electric tool, an assembly electric tool, and a railway electric tool, such as a drill, an electric grinder, an electric wrench, an electric screwdriver, a hammer drill, an impact drill, a concrete vibrator, and a planer, etc.; the energy storage device may be an energy storage wall, a base station energy storage, a container energy storage, and so on; the amusement device may be a carousel, a drop tower, and so on. The present application does not impose special restrictions on the above electrical devices.

[0043] For a new energy vehicle, the battery can be used as a driving power source to replace fossil fuels to provide driving power.

[0044] The above-mentioned battery can be a battery pack or a battery module. When the above-mentioned battery is a battery pack, the battery pack specifically includes a battery management system (BMS) and a plurality of the above-mentioned battery cells. The plurality of battery cells can be electrically connected in series, in parallel, or in a hybrid manner of series and parallel, and communicate with the battery management system to form a battery pack. The above-mentioned battery management system controls and monitors the working states of each battery cell. In addition, the plurality of battery cells can also be first connected in series and / or in parallel and form a battery module with a module management system, and then a plurality of battery modules are electrically connected in series, in parallel, or in a hybrid manner of series and parallel, and jointly constitute a battery pack with the battery management system.

[0045] Among them, the plurality of battery cells in the above-mentioned battery pack or battery module can be installed on a support structure such as a box body, a frame, or a bracket. Electric connection can be achieved between each battery cell and between the battery cell and the battery management system through a current collecting component such as a bus bar. The above-mentioned battery cell can be a lithium-ion battery, a sodium-ion battery, or a magnesium-ion battery, and its external contour can be cylindrical, flat, cuboid, or other shapes, but is not limited thereto. The battery cell in the embodiment of the present application is a cylindrical battery.

[0046] Generally, a battery cell includes a battery case and a bare electric core. The bare electric core is accommodated in the battery case. The bare electric core is the smallest unit for electrochemical reaction in the battery, and realizes the charge and discharge of the battery cell. It usually includes a positive electrode plate, a negative electrode plate, and a separator separating the positive electrode plate and the negative electrode plate. An electrolyte is injected into the battery case, and the electrolyte can infiltrate into the interior of the bare electric core, providing an ion migration path for the bare electric core to carry out electrochemical reaction and playing a role in conduction.

[0047] Figure 1 It is a schematic diagram of the overall structure of a cylindrical battery provided by an embodiment of the present application. Figure 2 It is a schematic cross-sectional view of a cylindrical battery provided by an embodiment of the present application. Figure 3 It is Figure 2 A partial enlarged schematic diagram of part A in

[0048] As Figures 1 to 3 shown, the present application provides a cylindrical battery 1, which includes a case 11, a bare electric core 12, a positive current collecting plate 13, an insulating seal 14, and an electrode terminal 15. The bare electric core 12 and the positive current collecting plate 13 are both installed in the case 11, and the positive current collecting plate 13 is arranged at one end of the bare electric core 12. The insulating seal 14 is at least partially located between the positive current collecting plate 13 and the case 11 to insulate and isolate the positive current collecting plate 13 and the case 11. The electrode terminal 15 passes through the insulating seal 14 and is connected to the positive current collecting plate 13.

[0049] The material of the housing 11 is usually a metal material or a polymer material. The housing 11 of the cylindrical battery 1 has a certain mechanical strength and corrosion resistance, and can act as a protective barrier, which can not only slow down the influence of the external environment on the inside of the cylindrical battery 1, but also reduce the risk of the electrolyte and electrode materials inside the cylindrical battery 1 polluting the external environment.

[0050] The bare cell 12 is the basic component unit of a lithium-ion battery, usually referring to a single lithium-ion battery or a cell with a similar structure. The bare cell 12 is formed by winding a positive electrode sheet, a separator, and a negative electrode sheet in sequence and stacking them. The positive electrode sheet of the bare cell 12 extends beyond the range facing the separator to form a positive electrode tab, and the negative electrode sheet extends beyond the range facing the separator to form a negative electrode tab.

[0051] The main function of the positive current collector plate 13 is to collect current, so as to effectively lead the current inside the battery from the end where the positive electrode tab is located to the external circuit.

[0052] The connection between the positive current collector plate 13 and the bare cell 12 usually refers to the connection relationship between the positive current collector plate 13 and the positive electrode tab of the bare cell 12. The positive current collector plate 13 and the positive electrode tab can be connected by laser welding, brazing or other welding methods. In actual production applications, the connection method between the positive current collector plate 13 and the positive electrode tab is usually laser welding.

[0053] Compared with other connection methods, laser welding has the advantages of high connection strength and good connection stability, so as to form a connection relationship with high strength and good stability between the positive current collector plate 13 and the bare cell 12, so that the cylindrical battery 1 can work more normally and stably.

[0054] The insulating and sealing member 14 has both an insulating function and a sealing function, integrating the components with insulating effects and the components with sealing effects, streamlining the components for insulation and sealing of the cylindrical battery 1, simplifying the processing and assembly steps of the cylindrical battery 1, and improving the installation efficiency of the cylindrical battery 1.

[0055] See Figure 3 , the insulating and sealing member 14 is formed with a groove, and the end of the housing 11 is inserted into the groove to realize the connection between the insulating and sealing member 14 and the housing 11. Among them, the groove walls of the insulating and sealing member 14 respectively cover the electrode terminal 15 and the positive current collector plate 13, avoiding direct contact between the housing 11 and the electrode terminal 15 and the positive current collector plate 13, so as to avoid short-circuiting of the positive and negative electrodes of the cylindrical battery 1, so that the cylindrical battery 1 can work normally.

[0056] The material of the insulating and sealing member 14 is generally natural rubber or synthetic rubber material. The insulating and sealing member 14 needs to have good corrosion resistance to electrolyte and compressive resistance, so that the insulating and sealing member 14 has good use stability and a long service life.

[0057] In the cylindrical battery 1, the electrode terminal 15 is generally the positive electrode terminal. The electrode terminal 15 is a conductive component for connecting the internal circuit and the external circuit of the cylindrical battery 1 to achieve the charge and discharge functions of the cylindrical battery 1. The electrode terminal 15 is usually connected to the positive current collector plate 13, thereby realizing the electrical connection between the electrode terminal 15 and the positive electrode tab of the bare battery cell 12. The electrode terminal 15 is usually made of a metal material with good electrical conductivity, such as metal copper, metal aluminum, metal steel, etc.

[0058] The insulating seal 14 and the positive current collector plate 13 can be directly connected, can be not connected, or can be indirectly connected.

[0059] In the case where the insulating seal 14 is directly connected to the positive current collector plate 13, the connection method between the insulating seal 14 and the positive current collector plate 13 can be an adhesive connection method. By setting structural adhesive between the insulating seal 14 and the positive current collector plate 13, it is convenient for the insulating seal 14 and the positive current collector plate 13 to form a stable connection relationship, so that the cylindrical battery 1 can maintain a stable working state.

[0060] In the case where the insulating seal 14 is not connected to the positive current collector plate 13, the insulating seal 14 can be arranged at one end of the bare battery cell so that the bare battery cell completely covers the positive electrode tab. The edge of the positive current collector plate fits or has a small gap with the circumference of the housing, so that the housing restricts the position of the positive current collector plate, so that the positive current collector plate can always be located between the positive current collector plate 13 and the housing 11, achieving a reliable insulating effect on the positive current collector plate 13 and the housing 11.

[0061] In the case where the insulating seal 14 is indirectly connected to the positive current collector plate 13, the connection method can be as described in the above embodiments of the present application, that is, the electrode terminal 15 passes through the insulating seal 14 and is connected to the positive current collector plate 13. After the electrode terminal 15 is connected to the positive current collector plate, the insulating seal 14 is restricted between the positive current collector plate 13 and the end of the electrode terminal far from the positive current collector plate 13, realizing the indirect connection between the insulating seal 14 and the positive current collector plate 13.

[0062] It can be seen that in the embodiments of the present application, since the electrode terminal 15 passes through the insulating seal 14 and is connected to the positive current collector plate 13, therefore, the connection components for connecting the electrode terminal 15 and the positive current collector plate 13, as well as the sealing components and insulating components required during the connection process between the electrode terminal 15 and the positive current collector plate 13 are omitted, so that the number of components required for the cylindrical battery 1 is small, and the connection relationship between the components of the cylindrical battery 1 is simple, thereby simplifying the design structure of the cylindrical battery 1 to reduce the design weight of the cylindrical battery 1, and further facilitating the lightweight design of the cylindrical battery 1.

[0063] See Figure 2 andFigure 3 , in an alternative embodiment, the electrode terminal 15 passes through the insulating seal 14 in a self-piercing riveting structure and is connected to the positive current collector plate 13.

[0064] Self-piercing riveting mainly utilizes the rivet to penetrate one layer of material close to the rivet. Then, under the action of the riveting die, the hollow structure of the edge of the rivet forms a non-penetrating cold deformation expansion in the other layer of sheet material away from the rivet, thereby forming a firm and reliable structural connection.

[0065] The self-piercing riveting structure can enable a firm connection relationship to be formed among the electrode terminal 15, the insulating seal 14, and the positive current collector plate 13 through a simple connection structure, so that the electrode terminal 15, the insulating seal 14, and the positive current collector plate 13 form a stable structural entity, and further simplify the design structure of the cylindrical battery 1.

[0066] In an alternative embodiment, the insulating seal 14 is integrally molded with the positive current collector plate 13 by injection molding.

[0067] Injection molding is a processing method for producing plastic products. By injecting the heat-melted plastic into the mold cavity under high pressure by an injection molding machine and cooling and solidifying it, a molded product is obtained.

[0068] Compared with common molding processes, injection molding has lower processing costs, better processing flexibility, and better product consistency, enabling a better connection strength to be formed between the insulating seal 14 and the positive current collector plate 13 and reducing the processing cost of the insulating seal 14.

[0069] Integrating the insulating seal 14 with the positive current collector plate 13 by injection molding, that is, combining the insulating seal 14 and the positive current collector plate 13 into one component, can further reduce the number of components of the cylindrical battery 1, and further simplify the design structure of the cylindrical battery 1.

[0070] Figure 4 This is a schematic cross-sectional view of a positive current collector plate provided by an embodiment of the present application.

[0071] As Figure 4 shown, the positive current collector plate 13 includes a connecting portion 131 and a current collecting portion 132 that are connected to each other. The thickness of the connecting portion 131 is greater than the thickness of the current collecting portion 132. The current collecting portion 132 is connected to the positive tab of the bare cell 12, and the electrode terminal 15 is connected to the connecting portion 131.

[0072] The connection manner between the connecting portion 131 and the current collecting portion 132 can be welding, bonding, integral molding, etc. In actual production applications, the connecting portion 131 and the current collecting portion 132 adopt an integrated design form, that is, the connecting portion 131 and the current collecting portion 132 can adopt an integral molding preparation process.

[0073] The one-piece manufacturing process can make the positive current collector plate 13 have better structural strength as a whole and simplify the production and processing steps of the positive current collector plate 13, thereby simplifying the production and processing steps of the cylindrical battery 1 and improving the production and processing efficiency of the cylindrical battery 1.

[0074] That the thickness of the connecting portion 131 is greater than the thickness of the current collecting portion 132 can make the strength of the connecting portion 131 greater than that of the current collecting portion 132. During the connection process between the electrode terminal 15 and the connecting portion 131, the possibility of the electrode terminal 15 penetrating through the connecting portion 131 is relatively small, which is convenient for the operator to select the connection method and connection force between the electrode terminal 15 and the connecting portion 131, thereby facilitating the connection between the electrode terminal 15 and the connecting portion 131. In addition, when the electrode terminal 15 is connected to the positive current collector plate 13 through the insulating seal 14 in a self-piercing riveting structure, the above setting form can ensure good connection strength between the electrode terminal 15 and the connecting portion 131 while reducing the risk of the electrode terminal 15 penetrating through the connecting portion 131, so as to avoid faults such as electrolyte leakage in the cylindrical battery 1, thereby keeping the cylindrical battery 1 in a good working state.

[0075] The connection method between the current collecting portion 132 and the positive electrode tab of the bare battery cell 12 can be laser welding, ultrasonic welding, resistance welding, bonding, etc. Among them, laser welding is more commonly used. Laser welding has the characteristics of high precision, high processing efficiency, high welding strength, and environmental friendliness, and can form a good connection relationship between the current collecting portion 132 and the positive electrode tab, and improve the production and processing efficiency of the cylindrical battery 1.

[0076] See Figure 3 and Figure 4 , in an optional embodiment, a recessed area is formed on the side of the insulating seal 14 facing the connecting portion 131. The connecting portion 131 protrudes from the current collecting portion 132, and at least part of the connecting portion is located in the recessed area.

[0077] The connecting portion 131 on the positive current collector plate 13 can be processed and manufactured by stamping. Stamping has the advantages of high production efficiency and high processing precision, and can improve the production efficiency and processing quality of the positive current collector plate 13.

[0078] Through the cooperation of the connecting portion 131 and the recessed area, it is not only convenient for the installation and positioning between the insulating seal 14 and the positive current collector plate 13 to reduce the installation difficulty, but also can improve the installation precision between the insulating seal 14 and the positive current collector plate 13, so that the insulating seal 14 can play a better insulating and sealing effect.

[0079] Specifically, the thickness of the connecting portion 131 is at least twice the thickness of the current collecting portion 132.

[0080] Such as Figure 4As shown, the thickness D1 of the connecting portion 131 is at least twice the thickness D2 of the current collecting portion 132. Specifically, the thickness D1 of the connecting portion 131 can be 2 times, 3 times, 4 times, 5 times, etc. of the thickness D2 of the current collecting portion 132. The specific multiple relationship between the thickness D1 of the connecting portion 131 and the thickness D2 of the current collecting portion 132 can be adjusted according to the product design requirements or customer needs, and the specific multiple relationship between the thickness D1 of the connecting portion 131 and the thickness D2 of the current collecting portion 132 is not limited in the embodiments of the present application.

[0081] The thickness D1 of the connecting portion 131 being at least twice the thickness D2 of the current collecting portion 132 can make the strength of the connecting portion 131 much greater than the strength of the current collecting portion 132, facilitating the connection between the electrode terminal 15 and the connecting portion 131. In addition, when the electrode terminal 15 is connected to the positive current collecting plate 13 through the insulating seal 14 in a self-piercing riveting structure, the above setting form can ensure good connection strength between the electrode terminal 15 and the connecting portion 131 while further reducing the risk of the electrode terminal 15 penetrating the connecting portion 131, so as to avoid faults such as electrolyte leakage in the cylindrical battery 1, thereby keeping the cylindrical battery 1 in a good working state.

[0082] Figure 5 is Figure 2 a partial enlarged schematic view at B in

[0083] As Figure 5 shown, optionally, the cylindrical battery 1 further includes a first seal 16. The housing 11 includes a cylindrical body 111 and a cover plate 112. The cover plate 112 is provided at one end of the bare battery cell 12 away from the positive current collecting plate 13. The first seal 16 is provided between the cover plate 112 and the cylindrical body 111 to achieve the sealed connection between the cover plate 112 and the cylindrical body 111.

[0084] The cylindrical body 111 is mainly used to accommodate the internal components of the cylindrical battery 1 including the bare battery cell 12, and can also provide a protective effect on the internal components of the cylindrical battery 1. The cylindrical body 111 is usually made of metal materials, such as steel, aluminum alloy, etc.

[0085] The cover plate 112 is usually used in combination with the cylindrical body 111 so that the cover plate 112 and the cylindrical body 111 together form the housing 11, and the cover plate 112 can play a role in fixing and sealing the cylindrical body 111.

[0086] The connection method between the cylindrical body 111 and the cover plate 112 can be non-detachable connection methods such as welding, gluing, riveting, etc., or detachable connections such as snap connection, threaded connection, etc.

[0087] The first seal 16 can be arranged between the cover plate 112 and the cylinder body 111 by means of sealant bonding. This method not only has a relatively low operation difficulty but also can improve the sealing effect of the first seal 16, so that the cylindrical battery 1 as a whole can maintain a stable working state.

[0088] In an alternative embodiment, the first seal 16 is arranged around the cover plate 112. The cylinder body 111 and the cover plate 112 are connected by a curling form. The first seal 16 is clamped between the cylinder body 111 and the cover plate 112 to achieve the sealed connection between the cover plate 112 and the cylinder body 111, thus further simplifying the connection structure of the cylindrical battery 1.

[0089] In another alternative embodiment, the cover plate 112 and the cylinder body 111 can be directly sealed and connected by a seal welding process. This method does not require the arrangement of the first seal 16, and while achieving the sealed connection between the cover plate 112 and the cylinder body 111, it provides the possibility of further simplifying the connection structure of the cylindrical battery 1.

[0090] Figure 6 It is a schematic structural diagram of a cover plate provided by an embodiment of the present application.

[0091] See Figure 6 Optionally, an explosion-proof structure 1121 is provided on the cover plate 112.

[0092] When a safety failure occurs in the cylindrical battery 1, such as overcharging, over-discharging, out-of-control of the electrochemical reaction, external short circuit, etc., a large amount of gas will be generated inside the cylindrical battery 1, resulting in an increase in the internal pressure of the cylindrical battery 1. When the pressure reaches the threshold value, the explosion-proof structure 1121 on the cover plate 112 will make the housing in an open state, releasing the excess gas inside the cylindrical battery 1 to balance the pressure difference inside and outside the cylindrical battery 1, thereby reducing the risk of safety accidents such as explosion caused by excessive internal pressure of the cylindrical battery 1, and further improving the safety performance of the cylindrical battery 1.

[0093] Specifically, the explosion-proof structure 1121 can be configured as an explosion-proof score line, an explosion-proof film or a pressure relief valve.

[0094] When the explosion-proof structure 1121 is configured as an explosion-proof score line, the thickness of the area on the cover plate 112 where the explosion-proof score line is provided is smaller than the thickness of the area on the cover plate 112 where no explosion-proof score line is provided. When a large amount of gas is generated inside the cylindrical battery 1 due to a safety failure and the pressure reaches the threshold value, the area on the cover plate 112 where the explosion-proof score line is provided will rupture under the action of the gas, so that the gas overflows along the rupture to balance the pressure inside and outside the cylindrical battery 1, thereby reducing the risk of safety accidents such as explosion caused by excessive internal pressure of the cylindrical battery 1 and improving the safety performance of the cylindrical battery 1.

[0095] When the explosion-proof structure 1121 is configured as an explosion-proof film, since the explosion-proof film is sensitive to the pressure change inside the cylindrical battery 1, when a large amount of gas is generated inside the cylindrical battery 1 due to a safety failure and the pressure reaches the threshold value, the explosion-proof film will rupture or form a release channel, so that the gas overflows along the area where the explosion-proof film is located, to balance the pressure inside and outside the cylindrical battery 1, thereby reducing the risk of safety accidents such as explosion caused by excessive internal pressure of the cylindrical battery 1, and improving the safety performance of the cylindrical battery 1.

[0096] When the explosion-proof structure 1121 is configured as a pressure relief valve, since most pressure relief valves are automatically controlled, when a large amount of gas is generated inside the cylindrical battery 1 due to a safety failure and the pressure reaches the threshold value, the pressure relief valve automatically opens, so that the gas overflows along the area where the pressure relief valve is located, to balance the pressure inside and outside the cylindrical battery 1, thereby reducing the risk of safety accidents such as explosion caused by excessive internal pressure of the cylindrical battery 1, and improving the safety performance of the cylindrical battery 1.

[0097] Figure 7 For Figure 2 The partial enlarged schematic diagram at C in

[0098] See Figure 7 In an alternative embodiment, a liquid injection hole 1122 is provided on the cover plate 112, and the cylindrical battery 1 further includes a second seal 17, and the second seal 17 is arranged at the liquid injection hole 1122 to seal the liquid injection hole 1122.

[0099] The liquid injection hole 1122 is mainly used to inject electrolyte into the cylindrical battery 1 during the production and processing of the battery cell. The second seal 17 can keep the liquid injection hole 1122 sealed during the injection of electrolyte. On the one hand, it can avoid the problem of liquid leakage during the use of the cylindrical battery 1, and on the other hand, it can prevent the inside of the cylindrical battery 1 from being eroded and affected by the external environment.

Claims

1. A cylindrical battery, characterized in that, It includes a shell, a bare cell, a positive electrode collector, an insulating seal and an electrode terminal, wherein the bare cell and the positive electrode collector are both installed in the shell, and the positive electrode collector is arranged at one end of the bare cell; The insulating seal is at least partially located between the positive electrode current collector and the shell to insulate and isolate the positive electrode current collector from the shell; The electrode terminal is connected to the positive electrode current collecting disk through the insulating seal.

2. The cylindrical battery according to claim 1, wherein, The electrode terminal is connected to the positive electrode current collecting disk through the insulating seal in a self-piercing riveting structure.

3. The cylindrical battery according to claim 1, wherein, The insulating seal is integrated with the positive electrode current collecting disk by injection molding.

4. The cylindrical battery according to claim 2 or 3, characterized in that, The positive electrode current collecting disk comprises a connecting portion and a current collecting portion connected to each other, wherein the thickness of the connecting portion is greater than the thickness of the current collecting portion; The current collecting portion is connected to the positive electrode tab of the bare cell, and the electrode terminal is connected to the connecting portion.

5. The cylindrical battery according to claim 4, characterized in that, The thickness of the connecting portion is at least twice the thickness of the current collecting portion.

6. The cylindrical battery according to claim 1, wherein The cylindrical battery further includes a first seal, the shell includes a barrel and a cover, the cover is provided at one end of the bare cell away from the positive electrode collector, and the first seal is provided between the cover and the barrel to achieve a sealed connection between the cover and the barrel; Alternatively, the shell includes a cylinder and a cover plate, the cover plate is arranged at one end of the bare cell away from the positive electrode current collecting disk, and the cover plate is welded to the cylinder to achieve a sealed connection between the cover plate and the cylinder.

7. The cylindrical battery according to claim 6, characterized in that, An explosion-proof structure is arranged on the cover plate.

8. The cylindrical battery according to claim 7, wherein The explosion-proof structure is configured as an explosion-proof mark, an explosion-proof membrane or a pressure relief valve.

9. A battery pack, characterized in that, Comprising a cylindrical battery as described in any one of claims 1-8.

10. An electrical device, characterized in that, Comprising the battery pack as claimed in claim 9.

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