Cylindrical battery, battery pack and electric device

Abstract

The application provides a cylindrical battery, a battery pack and an electrical equipment, and belongs to the technical field of secondary batteries. The cylindrical battery comprises a shell, a bare battery core, a positive electrode current collector, an insulating sealing element and an electrode terminal. The bare battery core and the positive electrode current collector are both installed in the shell, and the positive electrode current collector is arranged at one end of the bare battery core. The insulating sealing element is connected to the positive electrode current collector, and the insulating sealing element is at least partially located between the positive electrode current collector and the shell, so as to insulate and separate the positive electrode current collector and the shell. The electrode terminal is connected to the positive electrode current collector through the insulating sealing element. The connecting components for connecting the electrode terminal and the positive electrode current collector are omitted, and the sealing components and the insulating components required in the process of connecting the electrode terminal and the positive electrode current collector are omitted. The number of components required by the cylindrical battery is small, and the connection relationship between the components of the cylindrical battery is simple, so that the design structure of the cylindrical battery is simplified, the design weight of the cylindrical battery is reduced, and the lightweight design of the cylindrical battery is facilitated.

Description

[0001] This application is a divisional application of the parent application with application number "2024223240723", application date "2024.09.20", and title "A cylindrical battery, battery pack and electrical equipment". Technical Field

[0002] This application relates to the field of secondary battery technology, specifically to a cylindrical battery, a battery pack, and an electrical device. Background Technology

[0003] Cylindrical batteries are a common type of lithium-ion battery. Currently, most cylindrical batteries use riveting or threaded connections between the electrode terminals and the bare cell.

[0004] To ensure that the connection between the electrode terminals and the bare cell meets the safety performance requirements of lithium-ion batteries, the existing connection structure is relatively complex, resulting in a large design weight for cylindrical batteries, which is not conducive to the lightweight design of cylindrical batteries. Utility Model Content

[0005] This application provides a cylindrical battery, a battery pack, and an electrical device that can simplify the design structure of a cylindrical battery.

[0006] In a first aspect, this application provides a cylindrical battery, including a casing, a bare cell, a positive current collector, an insulating seal, and electrode terminals. Both the bare cell and the positive current collector are mounted within the casing, with the positive current collector located at one end of the bare cell. The insulating seal is at least partially located between the positive current collector and the casing to provide insulation between the positive current collector and the casing. The electrode terminals pass through the insulating seal and are connected to the positive current collector.

[0007] With the above solution, since the electrode terminals are connected to the positive current collector through the insulating seal, the connecting components for connecting the electrode terminals to the positive current collector, as well as the sealing and insulating components required during the connection process, are eliminated. This reduces the number of components required for the cylindrical battery and simplifies the connection relationship between the components, thereby simplifying the design structure of the cylindrical battery, reducing its design weight, and thus facilitating the lightweight design of the cylindrical battery.

[0008] In one possible design, the electrode terminals are connected to the positive current collector via an insulating seal using a self-piercing riveting structure.

[0009] The above scheme enables the self-piercing riveting structure to form a strong connection between the electrode terminals, insulating seals, and positive current collector through a simple connection structure, thereby forming a stable structural whole and simplifying the design structure of cylindrical batteries.

[0010] In one possible design, the insulating seal is injection molded and integrated into the positive current collector.

[0011] By combining the insulating seal and the positive electrode current collector into one component, the number of components in a cylindrical battery can be further reduced, thereby further simplifying the design structure of the cylindrical battery.

[0012] In one possible design, the positive current collector includes an interconnected connection portion and a current collector portion, with the thickness of the connection portion being greater than the thickness of the current collector portion. The current collector portion is connected to the positive electrode tab of the bare cell, and the electrode terminals are connected to the connection portion.

[0013] With the above-described design, the thickness of the connecting portion is greater than that of the current collector, resulting in greater strength for the connecting portion. This reduces the likelihood of the electrode terminal penetrating the connecting portion during connection, allowing operators to easily select the connection method and strength, thus facilitating the connection between the electrode terminal and the connecting portion. Furthermore, when the electrode terminal is connected to the positive electrode current collector via a self-piercing riveting structure through the insulating seal, the above-described configuration ensures a strong connection between the electrode terminal and the connecting portion while reducing the risk of electrode terminal penetration. This prevents electrolyte leakage and other malfunctions in the cylindrical battery, ensuring its optimal operating condition.

[0014] In one possible design, the thickness of the connector is at least twice the thickness of the collector.

[0015] The above-described design facilitates the connection between the electrode terminals and the connecting portion. Furthermore, when the electrode terminals are connected to the positive electrode current collector via a self-piercing riveting structure through the insulating seal, this configuration ensures a strong connection between the electrode terminals and the connecting portion while further reducing the risk of electrode terminal penetration, thus preventing electrolyte leakage and other malfunctions in the cylindrical battery and maintaining its optimal operating condition.

[0016] In one possible design, the cylindrical battery further includes a first seal. The housing comprises a cylindrical body and a cover plate, with the cover plate located at the end of the bare cell furthest from the positive current collector. The first seal is disposed between the cover plate and the cylindrical body to achieve a sealed connection between the cover plate and the cylindrical body. Alternatively, the housing comprises a cylindrical body and a cover plate, with the cover plate located at the end of the bare cell furthest from the positive current collector, and the cover plate is welded to the cylindrical body to achieve a sealed connection between the cover plate and the cylindrical body.

[0017] With the above design, the cylindrical body is primarily used to house the internal components of the cylindrical battery, including the bare battery cells, and also provides protection for these components. The cover plate is typically used in conjunction with the cylinder to form the casing, and the cover plate serves to secure and seal the cylinder. The first seal can be installed between the cover plate and the cylinder using sealant. This method is relatively easy to implement and improves the sealing effect of the first seal, thereby ensuring the overall stable operation of the cylindrical battery.

[0018] In one possible design, the cover plate is equipped with an explosion-proof structure.

[0019] Through the above solution, when a cylindrical battery experiences a safety malfunction, such as overcharging, over-discharging, uncontrolled electrochemical reaction, or external short circuit, a large amount of gas is generated inside the battery, leading to an increase in internal pressure. When the pressure reaches a threshold, the explosion-proof structure on the cover releases the excess gas inside the battery to balance the pressure difference between the inside and outside, thereby reducing the risk of explosions and other safety accidents caused by excessive internal pressure, and ultimately improving the safety performance of the cylindrical battery.

[0020] In one possible design, the explosion-proof structure is configured as explosion-proof markings, an explosion-proof membrane, or a pressure relief valve.

[0021] Through the above scheme, the explosion-proof structure can form a channel connecting the cylindrical battery to the outside world when thermal runaway occurs, connecting the internal and external spaces of the cylindrical battery, allowing the material inside the casing to be released in a directional manner, 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, and improving the safety performance of the cylindrical battery.

[0022] Secondly, the present invention provides a battery pack, including the cylindrical battery of the first aspect.

[0023] The beneficial effects of the cylindrical battery provided in the second aspect and the various possible designs of the second aspect can be found in the first aspect and the various possible implementations of the first aspect, and will not be repeated here.

[0024] Thirdly, the device itself provides an electrical appliance, including the battery pack of the second aspect.

[0025] The beneficial effects of the electrical equipment provided in the third aspect and the various possible designs of the third aspect can be found in the first aspect and the various possible implementations of the first aspect, and will not be repeated here.

[0026] In summary, a cylindrical battery consists of only a casing, bare cells, a positive current collector, and electrode terminals, requiring fewer components. Furthermore, both the bare cells and the positive current collector are housed within the casing, with the positive current collector located at one end of the bare cell. An insulating seal connects to the positive current collector, and the electrode terminals pass through the insulating seal and connect to the positive current collector. This simplifies the connections between the components, further simplifying the design structure and reducing the battery's weight, thus facilitating lightweight design. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of the overall structure of a cylindrical battery provided in an embodiment of this application.

[0028] Figure 2 This is a cross-sectional schematic diagram of a cylindrical battery provided in an embodiment of this application.

[0029] Figure 3 for Figure 2 A magnified view of a portion of point A in the middle.

[0030] Figure 4 This is a cross-sectional schematic diagram of a positive current collector provided in an embodiment of this application.

[0031] Figure 5 for Figure 2 A magnified view of a portion of point B in the middle.

[0032] Figure 6 This is a schematic diagram of the structure of a cover plate provided in an embodiment of this application.

[0033] Figure 7 for Figure 2 A magnified view of a portion of point C.

[0034] Reference numerals in the attached diagram: 1. Cylindrical battery; 11. Casing; 111. Cylindrical body; 112. Cover plate; 1121. Explosion-proof structure; 1122. Injection hole; 12. Bare cell; 13. Positive current collector; 131. Connecting part; 132. Current collector; 14. Insulating seal; 15. Electrode terminal; 16. First seal; 17. Second seal. Detailed Implementation

[0035] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0036] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used herein in the specification of the application is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms “comprising” and “having”, and any variations thereof, in the specification, claims and drawings of this application are intended to cover non-exclusive inclusion.

[0037] The term "embodiment" as used herein means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of the phrase "embodiment" in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0038] In this article, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can mean: A exists, A and B exist simultaneously, or B exists. Additionally, the character " / " in this article generally indicates that the preceding and following related objects have an "or" relationship.

[0039] The directional terms appearing in the following description refer to the directions shown in the figures and are not intended to limit the specific structure of the current limiting module of this application. For example, in the description of this application, the terms "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 figures. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0040] Furthermore, the terms "first," "second," etc., in the specification and claims of this application or in the aforementioned drawings are used to distinguish different objects rather than to describe a specific order, and may explicitly or implicitly include one or more of the features.

[0041] In the description of this application, unless otherwise stated, "multiple" means two or more (including two), and similarly, "multiple groups" means two or more (including two groups).

[0042] In the description of this application, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linkage" should be interpreted broadly. For example, "connection" or "linkage" in mechanical structures can refer to a physical connection, such as a fixed connection, for example, a connection fixed by a partition, such as a connection fixed by screws, bolts, or other partitions; a physical connection can also be a detachable connection, such as a snap-fit ​​or interlocking connection; a physical connection can also be an integral connection, such as a connection formed by welding, bonding, or integral molding. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances. In circuit structures, "connection" or "linkage" can refer not only to a physical connection but also to an electrical connection or a signal connection. For example, it can be a direct connection, i.e., a physical connection, or an indirect connection through at least one intermediate element, as long as the circuit is connected; it can also refer to the internal connection of two elements. A signal connection can refer not only to a signal connection through a circuit but also to a signal connection through a medium, such as radio waves. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0043] This application discloses a bare battery cell, a battery cell, a battery, and an electrical device. The battery cell includes the bare battery cell, and the electrical device includes the battery or the battery cell, and is capable of being powered by the battery or the battery cell. The electrical device can be a vehicle, mobile phone, portable device, laptop computer, ship, spacecraft, electric toy, power tool, energy storage device, amusement equipment, elevator, lifting equipment, etc. Vehicles can be gasoline-powered cars, natural gas-powered cars, or new energy vehicles; new energy vehicles can be pure electric vehicles, hybrid electric vehicles, or range-extended electric vehicles, etc.; spacecraft include airplanes, rockets, space shuttles, and spacecraft, etc.; electric toys include stationary or mobile electric toys, such as game consoles, electric car toys, electric boat toys, or electric airplane toys, etc.; power tools include metal cutting power tools, grinding power tools, assembly power tools, and railway power tools, such as electric drills, electric grinders, electric wrenches, electric screwdrivers, electric hammers, impact drills, concrete vibrators, and electric planers, etc.; energy storage devices can be energy storage walls, base station energy storage, containerized energy storage, etc.; amusement equipment can be carousels, drop towers, etc. This application does not impose special restrictions on the above-mentioned electrical equipment.

[0044] For new energy vehicles, the aforementioned batteries can serve as a driving power source, thereby replacing fossil fuels to provide driving power.

[0045] The aforementioned battery can be a battery pack or a battery module. When the battery is a battery pack, the battery pack specifically includes a battery management system (BMS) and multiple battery cells. Multiple battery cells can be electrically connected in series, parallel, or a combination of series and parallel connections, and communicate with the battery management system to form a battery pack. The battery management system controls and monitors the operating status of each battery cell. Alternatively, multiple battery cells can first be connected in series and / or parallel, and then connected with a module management system to form a battery module. These battery modules can then be electrically connected in series, parallel, or a combination of series and parallel connections, and together with the battery management system, form a battery pack.

[0046] In this embodiment, multiple battery cells in the battery pack or battery module can be mounted on supporting structures such as housings, frames, or brackets. The individual battery cells and the battery management system can be electrically connected via busbars, such as relays. The battery cells can be lithium-ion, sodium-ion, or magnesium-ion batteries, and their external contours can be cylindrical, flat, cuboid, or other shapes, but are not limited to these. In this embodiment, the battery cell is a cylindrical battery.

[0047] Typically, a battery cell consists of a battery casing and a bare cell housed within the casing. The bare cell is the smallest unit in the battery where electrochemical reactions occur, enabling the charging and discharging of the battery cell. It usually includes a positive electrode, a negative electrode, and a separator separating the positive and negative electrodes. An electrolyte is injected into the battery casing, allowing it to penetrate the bare cell and providing ion migration pathways for the electrochemical reactions, as well as serving a conductive function.

[0048] Figure 1 This is a schematic diagram of the overall structure of a cylindrical battery provided in an embodiment of this application. Figure 2 This is a cross-sectional schematic diagram of a cylindrical battery provided in an embodiment of this application. Figure 3 for Figure 2 A magnified view of a portion of point A in the middle.

[0049] like Figures 1 to 3 As shown, this application provides a cylindrical battery 1, including a casing 11, a bare cell 12, a positive current collector 13, an insulating seal 14, and electrode terminals 15. The bare cell 12 and the positive current collector 13 are both installed within the casing 11, with the positive current collector 13 located at one end of the bare cell 12. The insulating seal 14 is at least partially located between the positive current collector 13 and the casing 11 to provide insulation between them. The electrode terminals 15 pass through the insulating seal 14 and are connected to the positive current collector 13.

[0050] The casing 11 is usually made of metal or polymer. The casing 11 of the cylindrical battery 1 has a certain mechanical strength and corrosion resistance, which can play the role of a protective barrier. It can reduce the impact of the external environment on the inside of the cylindrical battery 1, and reduce the risk of the electrolyte and electrode materials inside the cylindrical battery 1 causing pollution to the external environment.

[0051] The bare cell 12 is the basic building block 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 stacking and winding a positive electrode sheet, a separator, and a negative electrode sheet in sequence. The positive electrode sheet of the bare cell 12 extends beyond the area directly opposite the separator to form a positive electrode tab, and the negative electrode sheet extends beyond the area directly opposite the separator to form a negative electrode tab.

[0052] The main function of the positive current collector 13 is to collect current so that the current inside the battery can be effectively discharged from the positive electrode tab to the external circuit.

[0053] The connection between the positive current collector 13 and the bare cell 12 usually refers to the connection between the positive current collector 13 and the positive tab of the bare cell 12. The positive current collector 13 and the positive tab can be connected by other welding methods such as laser welding and brazing. In actual production applications, the connection method between the positive current collector 13 and the positive tab is usually laser welding.

[0054] Compared to other connection methods, laser welding has the advantages of high connection strength and good connection stability, so as to form a strong and stable connection between the positive current collector 13 and the bare cell 12, thereby enabling the cylindrical battery 1 to work more normally and stably.

[0055] The insulating seal 14 has both insulating and sealing functions, integrating the insulating and sealing components into one unit. This simplifies the components used for insulation and sealing in the cylindrical battery 1, streamlines the processing and assembly steps of the cylindrical battery 1, and improves the installation efficiency of the cylindrical battery 1.

[0056] See Figure 3 The insulating seal 14 has a groove, and the end of the housing 11 is inserted into the groove to connect the insulating seal 14 to the housing 11. The groove walls of the insulating seal 14 cover the electrode terminal 15 and the positive current collector 13 respectively, preventing the housing 11 from directly contacting the electrode terminal 15 and the positive current collector 13, thereby preventing short circuit between the positive and negative terminals of the cylindrical battery 1 and enabling the cylindrical battery 1 to work normally.

[0057] The insulating seal 14 is generally made of natural rubber or synthetic rubber. The insulating seal 14 needs to have good resistance to electrolyte corrosion and pressure resistance so that the insulating seal 14 has good service stability and a long service life.

[0058] In the cylindrical battery 1, electrode terminal 15 is generally the positive terminal. Electrode terminal 15 is a conductive component used to connect the internal circuit and external circuit of the cylindrical battery 1 to realize the charging and discharging function of the cylindrical battery 1. Electrode terminal 15 is usually connected to the positive current collector 13, thereby realizing the electrical connection between electrode terminal 15 and the positive tab of the bare cell 12. Electrode terminal 15 is usually made of a metal material with good conductivity, such as copper, aluminum, or steel.

[0059] The insulating seal 14 and the positive current collector 13 can be directly connected, or they can be connected without connection, or they can be connected indirectly.

[0060] When the insulating seal 14 is directly connected to the positive current collector 13, the connection between the insulating seal 14 and the positive current collector 13 can be an adhesive bonding connection. By providing structural adhesive between the insulating seal 14 and the positive current collector 13, a stable connection can be formed between the insulating seal 14 and the positive current collector 13, thereby enabling the cylindrical battery 1 to maintain a stable working state.

[0061] When the insulating seal 14 is not connected to the positive current collector 13, the insulating seal 14 can be placed at one end of the bare cell so that the bare cell completely covers the positive tab. The edge of the positive current collector is in contact with the periphery of the housing or has a small gap, so that the housing restricts the position of the positive current collector and ensures that the positive current collector is always located between the positive current collector 13 and the housing 11, thus achieving a reliable insulation effect on the positive current collector 13 and the housing 11.

[0062] When the insulating seal 14 is indirectly connected to the positive current collector 13, the connection method can be as described in the above embodiments of this application, that is, the electrode terminal 15 passes through the insulating seal 14 and is connected to the positive current collector 13. After the electrode terminal 15 is connected to the positive current collector, the insulating seal 14 is restricted between the positive current collector 13 and the end of the electrode terminal away from the positive current collector 13, thereby realizing the indirect connection between the insulating seal 14 and the positive current collector 13.

[0063] As can be seen, in this embodiment, since the electrode terminal 15 passes through the insulating seal 14 and is connected to the positive current collector 13, the connecting component for connecting the electrode terminal 15 and the positive current collector 13, as well as the sealing component and insulating component required in the process of connecting the electrode terminal 15 and the positive current collector 13, are eliminated. This reduces the number of components required for the cylindrical battery 1 and simplifies the connection relationship between the components of the cylindrical battery 1, thereby simplifying the design structure of the cylindrical battery 1, reducing the design weight of the cylindrical battery 1, and thus facilitating the lightweight design of the cylindrical battery 1.

[0064] See Figure 2 and Figure 3 In one alternative embodiment, the electrode terminal 15 is connected to the positive current collector 13 through the insulating seal 14 in a self-piercing riveting structure.

[0065] Self-piercing riveting mainly utilizes the rivet to penetrate a layer of material close to the rivet. Then, under the action of the riveting die, the hollow structure of the rivet's cutting edge forms a non-penetrating cold deformation expansion within a layer of sheet material away from the rivet, thereby forming a strong and reliable structural connection.

[0066] The self-piercing riveting structure allows the electrode terminal 15, the insulating seal 14, and the positive current collector 13 to form a strong connection through a simple connection structure, thereby forming a stable structural whole with the electrode terminal 15, the insulating seal 14, and the positive current collector 13, which simplifies the design structure of the cylindrical battery 1.

[0067] In an alternative embodiment, the insulating seal 14 is injection molded into the positive current collector 13.

[0068] Injection molding is a processing method used to produce plastic products. It involves injecting molten plastic into a mold cavity under high pressure using an injection molding machine, and then cooling and solidifying it to obtain the molded product.

[0069] Compared with common molding processes, injection molding has lower processing costs, better processing flexibility and better product consistency, so that the insulating seal 14 and the positive current collector 13 can form a better connection strength and reduce the processing cost of the insulating seal 14.

[0070] The insulating seal 14 is integrated into the positive electrode current collector 13 by injection molding, that is, the insulating seal 14 and the positive electrode current collector 13 are combined into one component, which can further reduce the number of components of the cylindrical battery 1 and further simplify the design structure of the cylindrical battery 1.

[0071] Figure 4 This is a cross-sectional schematic diagram of a positive current collector provided in an embodiment of this application.

[0072] like Figure 4 As shown, the positive current collector 13 includes a connecting portion 131 and a current collector 132 that are connected to each other. The thickness of the connecting portion 131 is greater than the thickness of the current collector 132. The current collector 132 is connected to the positive electrode tab of the bare cell 12, and the electrode terminal 15 is connected to the connecting portion 131.

[0073] The connection method of the connecting part 131 and the current collecting part 132 can be welding, gluing, integral molding, etc. In actual production applications, the connecting part 131 and the current collecting part 132 adopt an integrated design, that is, the connecting part 131 and the current collecting part 132 can adopt an integral molding manufacturing process.

[0074] The one-piece molding process can give the positive current collector 13 better structural strength and simplify the production and processing steps of the positive current collector 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.

[0075] The fact that the thickness of the connecting portion 131 is greater than that of the current collector 132 makes the strength of the connecting portion 131 greater than that of the current collector 132. During the connection process between the electrode terminal 15 and the connecting portion 131, the possibility of the electrode terminal 15 penetrating the connecting portion 131 is relatively small. This allows operators to easily select the connection method and strength between the electrode terminal 15 and the connecting portion 131, thus facilitating the connection between the electrode terminal 15 and the connecting portion 131. Furthermore, when the electrode terminal 15 is connected to the positive electrode current collector 13 via the insulating seal 14 using a self-piercing riveting structure, the above arrangement can ensure a good connection strength between the electrode terminal 15 and the connecting portion 131 while reducing the risk of the electrode terminal 15 penetrating the connecting portion 131. This avoids malfunctions such as electrolyte leakage in the cylindrical battery 1, thereby maintaining the cylindrical battery 1 in good working condition.

[0076] The connection between the current collector 132 and the positive electrode tab of the bare cell 12 can be achieved through laser welding, ultrasonic welding, resistance welding, adhesive bonding, etc. Among these, laser welding is the most commonly used. Laser welding is characterized by high precision, high processing efficiency, high welding strength, and environmental friendliness. It can create a good connection between the current collector 132 and the positive electrode tab and improve the production and processing efficiency of the cylindrical battery 1.

[0077] See Figure 3 and Figure 4 In one alternative embodiment, the insulating seal 14 has a recessed area on the side facing the connection portion 131, the connection portion 131 protrudes from the current collection portion 132, and the connection portion is at least partially located within the recessed area.

[0078] The connecting part 131 on the positive current collector 13 can be manufactured by stamping. Stamping has the advantages of high production efficiency and high processing accuracy, which can improve the production efficiency and processing quality of the positive current collector 13.

[0079] The cooperation between the connecting part 131 and the recessed area facilitates the installation and positioning between the insulating seal 14 and the positive current collector 13, thereby reducing the installation difficulty. It also improves the installation accuracy between the insulating seal 14 and the positive current collector 13, so that the insulating seal 14 can achieve a better insulation and sealing effect.

[0080] Specifically, the thickness of the connecting portion 131 is at least twice the thickness of the collecting portion 132.

[0081] like Figure 4As shown, the thickness D1 of the connecting portion 131 is at least twice the thickness D2 of the collecting portion 132. Specifically, the thickness D1 of the connecting portion 131 can be 2, 3, 4, 5, etc., times the thickness D2 of the collecting portion 132. The specific multiple relationship between the thickness D1 of the connecting portion 131 and the thickness D2 of the collecting portion 132 can be adjusted according to product design needs or customer requirements. In this embodiment, no specific multiple relationship between the thickness D1 of the connecting portion 131 and the thickness D2 of the collecting portion 132 is limited.

[0082] The thickness D1 of the connecting portion 131 is at least twice the thickness D2 of the current collector 132, which makes the strength of the connecting portion 131 much greater than that of the current collector 132, facilitating the connection between the electrode terminal 15 and the connecting portion 131. Furthermore, when the electrode terminal 15 is connected to the positive electrode current collector 13 via the insulating seal 14 using a self-piercing riveting structure, the above arrangement can ensure a 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, thus avoiding malfunctions such as electrolyte leakage in the cylindrical battery 1, thereby maintaining the cylindrical battery 1 in good working condition.

[0083] Figure 5 for Figure 2 A magnified view of a portion of point B in the middle.

[0084] like Figure 5 As shown, optionally, the cylindrical battery 1 further includes a first sealing element 16. The housing 11 includes a cylindrical body 111 and a cover plate 112. The cover plate 112 is located at the end of the bare cell 12 away from the positive current collector 13. The first sealing element 16 is located between the cover plate 112 and the cylindrical body 111 to achieve a sealed connection between the cover plate 112 and the cylindrical body 111.

[0085] The cylindrical body 111 is mainly used to house the internal components of the cylindrical battery 1, including the bare battery cell 12, and also provides protection for the internal components of the cylindrical battery 1. The cylindrical body 111 is usually made of metal materials, such as steel or aluminum alloy.

[0086] The cover plate 112 is usually used in conjunction with the cylinder 111 so that the cover plate 112 and the cylinder 111 together form the shell 11. The cover plate 112 can play the role of fixing and sealing the cylinder 111.

[0087] The connection between the cylinder 111 and the cover plate 112 can be a non-detachable connection such as welding, gluing, or riveting, or a detachable connection such as snap-fit ​​or threaded connection.

[0088] The first sealing element 16 can be installed between the cover plate 112 and the cylinder 111 by means of sealant bonding. This method has low operation difficulty and can improve the sealing effect of the first sealing element 16, thereby keeping the cylindrical battery 1 in a stable working state.

[0089] In one alternative embodiment, a first sealing element 16 is disposed around the cover plate 112, and the cylinder 111 and the cover plate 112 are connected by a rolled edge. The first sealing element 16 is sandwiched between the cylinder 111 and the cover plate 112 to achieve a sealed connection between the cover plate 112 and the cylinder 111, thereby further simplifying the connection structure of the cylindrical battery 1.

[0090] In another alternative embodiment, the cover plate 112 and the cylinder 111 can be directly sealed by a sealing welding process. This method eliminates the need for a first sealing element 16 and can provide the possibility of further simplifying the connection structure of the cylindrical battery 1 while achieving a sealed connection between the cover plate 112 and the cylinder 111.

[0091] Figure 6 This is a schematic diagram of the structure of a cover plate provided in an embodiment of this application.

[0092] See Figure 6 Optionally, the cover plate 112 is provided with an explosion-proof structure 1121.

[0093] When a safety malfunction occurs in the cylindrical battery 1, such as overcharging or over-discharging, uncontrolled electrochemical reaction, or external short circuit, a large amount of gas will be generated inside the cylindrical battery 1, leading to an increase in internal pressure. When the pressure reaches a threshold, the explosion-proof structure 1121 on the cover plate 112 will open the casing, releasing excess gas inside the cylindrical battery 1 to balance the pressure difference between the inside and outside of the cylindrical battery 1. This reduces the risk of safety accidents such as explosion caused by excessive internal pressure, thereby improving the safety performance of the cylindrical battery 1.

[0094] Specifically, the explosion-proof structure 1121 can be configured as explosion-proof markings, an explosion-proof membrane, or a pressure relief valve.

[0095] When the explosion-proof structure 1121 is configured with explosion-proof markings, the thickness of the area on the cover plate 112 with explosion-proof markings is less than the thickness of the area on the cover plate 112 without explosion-proof markings. This means that when the cylindrical battery 1 generates a large amount of gas inside due to a safety malfunction and the pressure reaches a threshold, the area on the cover plate 112 with explosion-proof markings will rupture under the action of the gas, causing the gas to overflow along the rupture point. This balances the pressure inside and outside the cylindrical battery 1, thereby reducing the risk of safety accidents such as explosion caused by excessive internal pressure in the cylindrical battery 1, and improving the safety performance of the cylindrical battery 1.

[0096] When the explosion-proof structure 1121 is configured as an explosion-proof membrane, the explosion-proof membrane is sensitive to pressure changes inside the cylindrical battery 1. When the cylindrical battery 1 generates a large amount of gas inside due to a safety fault and the pressure reaches a threshold, the explosion-proof membrane will rupture or form a release channel, allowing the gas to overflow along the area where the explosion-proof membrane is located, thereby balancing the pressure inside and outside the cylindrical battery 1. This reduces the risk of safety accidents such as explosion caused by excessive internal pressure in the cylindrical battery 1, and improves the safety performance of the cylindrical battery 1.

[0097] When the explosion-proof structure 1121 is configured as a pressure relief valve, since most pressure relief valves are automatically controlled, when the cylindrical battery 1 generates a large amount of gas inside due to a safety fault and the pressure reaches the threshold, the pressure relief valve automatically opens, allowing the gas to overflow along the area where the pressure relief valve is located, so as 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.

[0098] Figure 7 for Figure 2 A magnified view of a portion of point C.

[0099] See Figure 7 In one optional embodiment, the cover plate 112 is provided with a liquid injection hole 1122, and the cylindrical battery 1 also includes a second sealing member 17, which is disposed on the liquid injection hole 1122 to seal the liquid injection hole 1122.

[0100] The electrolyte injection hole 1122 is mainly used to inject electrolyte into the cylindrical battery 1 during the cell production and processing. The second sealing element 17 can keep the electrolyte injection hole 1122 sealed during electrolyte injection. On the one hand, it can prevent leakage of the cylindrical battery 1 during use, and on the other hand, it can prevent the cylindrical battery 1 from being corroded and affected by the external environment.

Claims

1. A cylindrical battery, characterized in that, The device includes a housing, a bare battery cell, a positive current collector, an insulating seal, and electrode terminals. The bare battery cell and the positive current collector are both installed inside the housing, and the positive current collector is located at one end of the bare battery cell. The insulating seal is disposed in the gap between the positive current collector, the electrode terminal and the housing; The electrode terminal passes through the insulating seal and is connected to the positive current collector.

2. The cylindrical battery according to claim 1, characterized in that, The electrode terminals are connected to the positive current collector via the insulating seal using a self-piercing riveting structure.

3. The cylindrical battery according to claim 1, characterized in that, The insulating seal is injection molded into the positive current collector, or the insulating seal is connected to the positive current collector by structural adhesive.

4. The cylindrical battery according to claim 1, characterized in that, The insulating seal has a groove, and the end of the housing is inserted into the groove.

5. The cylindrical battery according to claim 4, characterized in that, The groove walls cover the electrode terminals and the positive current collector, respectively.

6. The cylindrical battery according to claim 2 or 3, characterized in that, The positive electrode current collector includes a connecting part and a current collecting part that are connected to each other, and the thickness of the connecting part is greater than the thickness of the current collecting part; The current collector is connected to the positive electrode tab of the bare battery cell, and the electrode terminal is connected to the connection part.

7. The cylindrical battery according to claim 6, characterized in that, The thickness of the connecting part is at least twice the thickness of the current collecting part.

8. The cylindrical battery according to claim 6, characterized in that, The insulating seal has a recessed area on the side facing the connection portion, the connection portion protrudes from the current collection portion, and at least a portion of the connection portion is located in the recessed area.

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

10. An electrical appliance, characterized in that, Includes the battery pack as described in claim 9.

Images