Battery cell, battery, electric device, and method and apparatus for manufacturing battery cell

Abstract

The embodiment of the application provides a battery monomer, a battery, a power utilization device, a manufacturing method and equipment of the battery monomer, and belongs to the technical field of batteries. The battery monomer comprises a shell, an electrode assembly, an end cover and a current collecting member. The shell has an opening. The electrode assembly is accommodated in the shell. The end cover covers the opening and is in sealing connection with the shell. The current collecting member is accommodated in the shell and is located at the side of the electrode assembly facing the end cover. The current collecting member is configured to connect the shell and the electrode assembly, so that the electrode assembly is electrically connected with the shell. The structure of the battery monomer realizes the electrical connection between the electrode assembly and the shell through the current collecting member. In the process of assembling the battery monomer, the current collecting member can be connected with the shell in the interior of the shell. After the current collecting member is connected with the electrode assembly and the shell, the end cover is covered on the opening of the shell and is in sealing connection with the shell, so that the electrical connection between the electrode assembly and the shell is more convenient.

Description

[0001] Cross-reference to related applications

[0002] This application claims priority to international patent application PCT / CN2021 / 104779, filed on July 6, 2021, entitled “Battery cell, battery, electrical device and method and apparatus for manufacturing battery cell”, the entire contents of which are incorporated herein by reference. Technical Field

[0003] This application relates to the field of battery technology, and more specifically, to a battery cell, a battery, an electrical device, and a method and apparatus for manufacturing the battery cell. Background Technology

[0004] The batteries most commonly used in vehicles are lithium-ion batteries. As a type of rechargeable battery, lithium-ion batteries have advantages such as small size, high energy density, high power density, many cycles, and long storage time.

[0005] A battery cell generally includes a casing and an electrode assembly. The casing is used to house the electrode assembly and the electrolyte. The electrode assembly generally includes a positive electrode and a negative electrode. Electrical energy is generated by the movement of metal ions (such as lithium ions) between the positive and negative electrode.

[0006] For a typical battery cell, the electrode assembly needs to be electrically connected to the casing so that the casing can serve as the positive or negative output electrode of the battery cell. Currently, it is not convenient to achieve an electrical connection between the electrode assembly and the casing. Summary of the Invention

[0007] This application provides a battery cell, a battery, an electrical device, and a method and apparatus for manufacturing the battery cell, which can more easily realize the electrical connection between the electrode assembly and the casing.

[0008] In a first aspect, embodiments of this application provide a battery cell, comprising: a housing having an opening; an electrode assembly housed within the housing; an end cap covering the opening and sealingly connected to the housing; and a current collector housed within the housing and located on the side of the electrode assembly facing the end cap, the current collector being configured to connect the housing and the electrode assembly to electrically connect the electrode assembly to the housing.

[0009] In the above technical solution, the current collector is located on the side of the electrode assembly facing the end cap. The electrode assembly and the housing are electrically connected through the current collector. The end cap is closed on the opening of the housing and is sealed to the housing. This structure allows the current collector to be connected to the housing from inside the housing during the assembly of the battery cell. After connecting the current collector to the electrode assembly and the housing, the end cap is closed on the opening of the housing and sealed to the housing, making the electrical connection between the electrode assembly and the housing more convenient.

[0010] In some embodiments, the current collection member is welded to the housing.

[0011] In the above technical solution, the current collector is welded to the shell, and the connection between the current collector and the shell is simple, which can improve the firmness of the connection between the current collector and the shell and realize stable current flow between the current collector and the shell.

[0012] In some embodiments, the current collector is welded to the housing to form a welded portion, which is used to fix the current collector and the housing, and the welded portion is located inside the housing.

[0013] In the above technical solution, the welded part formed by welding the current collector to the shell is located inside the shell, which reduces the risk of damage to the outer structure of the shell caused by the welded part being located outside the shell during the welding process of the current collector to the shell, reduces the risk of shell corrosion, and improves the service life of the battery cell.

[0014] In some embodiments, a first limiting portion is provided on the inner side of the housing, the first limiting portion being used to restrict the end cap from moving in the direction facing the electrode assembly; the current collector is welded to the first limiting portion.

[0015] In the above technical solution, the first limiting part limits the end cover, restricting its movement in the direction facing the electrode assembly. The current collector is welded to the first limiting part that limits the end cover, effectively utilizing the first limiting part and facilitating the welding and fixing of the current collector.

[0016] In some embodiments, the current collector includes: a body portion for connection to an electrode assembly, the body portion being located on the side of the first limiting portion facing the electrode assembly, the first limiting portion being used to restrict the body portion from disengaging from the housing in a direction away from the electrode assembly.

[0017] In the above technical solution, the first limiting part plays a limiting role on the main body part. The first limiting part can restrict the main body part from detaching from the housing in the direction away from the electrode assembly. The first limiting part can separate the end cover and the main body part. The main body part is less likely to affect the seal between the end cover and the housing, thereby improving the sealing performance between the end cover and the housing.

[0018] In some embodiments, the body portion abuts against the side of the first limiting portion facing the electrode assembly and is welded to the first limiting portion.

[0019] In the above technical solution, the main body abuts against the side of the first limiting part facing the electrode assembly and is welded to the first limiting part, so that the entire current collector has good firmness after being fixed to the first limiting part, increasing the contact area between the current collector and the first limiting part, thereby increasing the flow area between the shell and the current collector.

[0020] In some embodiments, the current collection member further includes: an elastic portion connected to the body portion, the elastic portion abutting against the first limiting portion and being welded to the first limiting portion.

[0021] In the above technical solution, the elastic part of the current collector abuts against the first limiting part and is welded to the first limiting part. The elastic part can undergo elastic deformation according to the change in distance between the main body and the first limiting part, reducing the risk of the electrode assembly moving inside the casing due to the vibration of the battery cell, causing the electrical connection between the main body and the electrode assembly to fail.

[0022] In some embodiments, the elastic portion is a spring sheet bent and arranged on the body portion.

[0023] In the above technical solution, the elastic part is a spring sheet that is bent and arranged in the body part. It has a simple structure and good deformation ability.

[0024] In some embodiments, the current collecting member further includes: a first connecting portion connected to the body portion, the first connecting portion extending at least partially to the inner peripheral side of the first limiting portion, and the first connecting portion being welded to the first limiting portion.

[0025] In the above technical solution, the first connecting part of the current collecting component extends at least partially to the inner circumferential side of the first limiting part, and the first connecting part is welded to the first limiting part, thereby reducing the welding difficulty between the current collecting component and the first limiting part.

[0026] In some embodiments, the first connecting portion is a protrusion extending from the body portion in a direction away from the electrode assembly, the protrusion being used to form a positioning engagement with the inner peripheral surface of the first limiting portion.

[0027] In the above technical solution, the first connecting part is a protrusion that forms a positioning fit with the inner circumferential surface of the first limiting part. This positioning fit reduces the risk of the current collecting component wobbling during the welding process between the first connecting part and the first limiting part, reduces welding difficulty, and improves the robustness of the welded components. Simultaneously, it increases the contact area between the housing and the current collecting component, thereby increasing the flow area between them.

[0028] In some embodiments, the body portion has an inner surface facing the electrode assembly and an outer surface facing away from the electrode assembly, the protrusion extending from the outer surface in a direction facing away from the electrode assembly; the current collector further includes a recess recessing from the inner surface in a direction facing away from the electrode assembly toward the protrusion.

[0029] In the above technical solution, the current collector is provided with a recess that is recessed into the protrusion from the inner surface of the main body in the direction away from the electrode assembly. On the one hand, the material of the current collector is reduced and the manufacturing cost is reduced. On the other hand, the deformation capacity of the protrusion is improved, so that the protrusion elastically abuts against the first limiting part, and the protrusion and the first limiting part are in good contact.

[0030] In some embodiments, both the protrusion and the recess are annular structures extending circumferentially along the first limiting portion.

[0031] In the above technical solution, both the convex and concave parts are annular structures extending circumferentially along the first limiting part, which makes the convex part have better deformation ability.

[0032] In some embodiments, in the direction in which the first connecting portion extends from the body portion in a direction away from the electrode assembly, the end of the first connecting portion away from the body portion does not extend beyond the first limiting portion.

[0033] In the above technical solution, the end of the first connecting part that is away from the main body does not exceed the first limiting part, so the first connecting part is less likely to interfere with the end cover and improves the sealing between the end cover and the housing.

[0034] In some embodiments, the first connecting portion is welded to the inner peripheral surface of the first limiting portion, the inner peripheral surface having a boundary position, and the radial dimension of the inner peripheral surface gradually increases from the boundary position to both ends of the inner peripheral surface; in the direction in which the first connecting portion extends from the body portion in a direction away from the electrode assembly, one end of the first connecting portion away from the body portion extends beyond the boundary position.

[0035] In the above technical solution, the end of the first connecting part that is away from the main body part extends beyond the dividing position, so that a weld seam is formed between the outer peripheral surface of the first connecting part and the first limiting part, which facilitates welding and fixing the first connecting part and the first limiting part, and improves the firmness of the first connecting part and the first limiting part after welding.

[0036] In some embodiments, the first connection portion includes: an extension portion connected to the body portion, the extension portion extending from the body portion in a direction away from the electrode assembly, the extension portion extending at least partially to the inner peripheral side of the first limiting portion; and a limiting portion connected to the extension portion, the limiting portion abutting against the side of the first limiting portion away from the electrode assembly and being welded to the first limiting portion.

[0037] In the above technical solution, the limiting segment abuts against the side of the first limiting part away from the electrode assembly and is welded to the first limiting part. The limiting segment plays a limiting role, which improves the firmness of the current collector after welding with the first limiting part and increases the contact area between the current collector and the first limiting part, thereby increasing the flow area between the housing and the current collector.

[0038] In some embodiments, the first limiting portion is an annular structure extending circumferentially along the housing.

[0039] In the above technical solution, the first limiting part is a ring structure, which is easy to mold and manufacture. The first limiting part can restrict the end cap throughout the entire circumference, thereby improving the limiting ability of the first limiting part on the end cap.

[0040] In some embodiments, a roller groove is provided on the outer side of the housing at a position corresponding to the first limiting portion.

[0041] In the above technical solution, the outer side of the shell is provided with a roller groove. During the process of forming the roller groove, the shell will form a first limiting part at the position corresponding to the roller groove, which can simplify the forming process of the first limiting part.

[0042] In some embodiments, the battery cell further includes a seal; the end cap and the housing are sealed together by the seal.

[0043] In the above technical solution, the end cap and the housing are sealed together by a sealing element to improve the sealing performance of the end cap and the housing.

[0044] In some embodiments, the seal is configured to insulate the housing from the end cap.

[0045] In the above technical solution, the sealing element insulates and isolates the housing from the end cover. The sealing element serves both a sealing function and an insulating function between the housing and the end cover, thereby improving the sealing performance between the end cover and the housing while reducing the risk of the end cover becoming electrified.

[0046] In some embodiments, the seal is configured to circumferentially cover the end cap along the opening.

[0047] In the above technical solution, the sealing element circumferentially covers the end cap along the opening of the housing. On the one hand, this improves the sealing performance of the sealing element on the end cap and the housing; on the other hand, it improves the overall integrity of the sealing element and the housing. During the assembly of the battery cell, the sealing element can be first covered on the end cap, and then the end cap and the sealing element can be installed as a whole onto the housing.

[0048] In some embodiments, the housing is provided with a second limiting portion at one end of the opening, the second limiting portion being used to restrict the end cap from disengaging from the housing in a direction away from the electrode assembly; in the thickness direction of the end cap, at least a portion of the sealing member is located between the end cap and the second limiting portion to achieve a sealed connection between the end cap and the housing.

[0049] In the above technical solution, the second limiting part restricts the end cap from detaching from the housing in the direction away from the electrode assembly. At least a portion of the sealing element is located between the end cap and the second limiting part, achieving a sealed connection between the end cap and the housing and improving the sealing performance between the end cap and the housing.

[0050] In some embodiments, the seal includes a housing and a second connecting portion connected to the housing; at least a portion of the end cap is located within the housing, and in the thickness direction of the end cap, the second connecting portion is located between the end cap and a second limiting portion to achieve a sealed connection between the end cap and the housing.

[0051] In the above technical solution, the sealing element includes an interconnected enclosure and a second connecting part. At least a portion of the end cap is located within the enclosure, and the second connecting part is located between the end cap and the limiting part. The sealing element has a simple structure and achieves good sealing between the end cap and the housing, while also ensuring good integrity between the sealing element and the end cap.

[0052] Secondly, embodiments of this application provide a battery, including multiple battery cells provided in any one of the embodiments of the first aspect.

[0053] Thirdly, embodiments of this application provide an electrical device including a battery cell provided in any one of the embodiments of the first aspect.

[0054] Fourthly, embodiments of this application provide a method for manufacturing a battery cell, comprising: providing a housing having an opening; providing an electrode assembly; providing an end cap; providing a current collector; connecting the current collector to the electrode assembly; accommodating the electrode assembly and the current collector within the housing; closing the end cap to the opening and sealing the end cap to the housing, such that the current collector is located on the side of the electrode assembly facing the end cap; wherein the housing and the electrode assembly are electrically connected through the current collector.

[0055] In some embodiments, before closing the end cap to the opening, the manufacturing method further includes welding the current collector to the housing from the inside of the housing.

[0056] Fifthly, embodiments of this application also provide a manufacturing apparatus for a battery cell, comprising: a first providing device for providing a housing having an opening; a second providing device for providing an electrode assembly; a third providing device for providing an end cap; a fourth providing device for providing a current collector; an assembly device for connecting the current collector to the electrode assembly; further comprising for accommodating the electrode assembly and the current collector within the housing; and further comprising for covering the opening with the end cap and sealing the end cap to the housing, such that the current collector is located on the side of the electrode assembly facing the end cap; wherein the housing and the electrode assembly are electrically connected through the current collector. Attached Figure Description

[0057] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0058] Figure 1 This application provides structural schematic diagrams of vehicles for some embodiments;

[0059] Figure 2 This application provides schematic diagrams of the battery structure for some embodiments.

[0060] Figure 3 Exploded views of a single battery cell provided in some embodiments of this application;

[0061] Figure 4 for Figure 3 A cross-sectional view of the battery cell shown;

[0062] Figure 5 Partial views of a battery cell provided for some embodiments of this application;

[0063] Figure 6 A partial view of a battery cell provided for some embodiments of this application;

[0064] Figure 7 for Figure 4 A partial view of the battery cell shown;

[0065] Figure 8 A partial view of a battery cell provided for some embodiments of this application;

[0066] Figure 9 A flowchart illustrating a method for manufacturing a single battery cell according to some embodiments of this application;

[0067] Figure 10This is a schematic diagram of the structure of a battery cell manufacturing apparatus provided in some embodiments of this application.

[0068] Icons: 10-Battery cell; 11-Housing; 111-Inner side; 112-First limiting part; 1121-Inner circumferential surface; 1121a-Boundary position; 113-Roller groove; 114-Second limiting part; 12-Electrode assembly; 13-End cap; 14-Current collector; 141-Body part; 1411-Inner surface; 1412-Outer surface; 142-Elastic part; 143-First connecting part; 1431-Extension section; 1432-Limiting section; 144-Recess; 15-Seal ; 151-Enclosure; 152-Second connecting part; 153-Third connecting part; 16-Electrode terminal; 17-Welding part; 20-Box; 21-First part; 22-Second part; 100-Battery; 200-Controller; 300-Motor; 1000-Vehicle; 2000-Manufacturing equipment; 2100-First supply device; 2200-Second supply device; 2300-Third supply device; 2400-Fourth supply device; 2500-Assembly device; Z-Thickness direction. Detailed Implementation

[0069] 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 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.

[0070] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used in the description of this 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 description, claims, and accompanying drawings of this application are intended to cover non-exclusive inclusion. The terms "first," "second," etc., in the description, claims, or accompanying drawings of this application are used to distinguish different objects, not to describe a specific order or hierarchy.

[0071] In this application, the reference to "embodiment" 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 this phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment that is mutually exclusive with other embodiments.

[0072] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "attachment" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0073] In the embodiments of this application, the same reference numerals denote the same components, and for the sake of brevity, detailed descriptions of the same components are omitted in different embodiments. It should be understood that the thickness, length, width, and other dimensions of various components in the embodiments of this application shown in the accompanying drawings, as well as the overall thickness, length, width, and other dimensions of the integrated device, are merely illustrative and should not constitute any limitation on this application.

[0074] In this application, "multiple" means two or more (including two).

[0075] In this application, the battery cell may include lithium-ion secondary batteries, lithium-ion primary batteries, lithium-sulfur batteries, sodium-lithium-ion batteries, sodium-ion batteries, or magnesium-ion batteries, etc., and the embodiments of this application are not limited to these. The battery cell may be cylindrical, flat, cuboid, or other shapes, etc., and the embodiments of this application are not limited to these. Battery cells are generally divided into three types according to their packaging method: cylindrical battery cells, square battery cells, and pouch battery cells, and the embodiments of this application are not limited to these.

[0076] The battery mentioned in the embodiments of this application refers to a single physical module comprising one or more battery cells to provide higher voltage and capacity. For example, the battery mentioned in this application may include a battery module or a battery pack. A battery generally includes a housing for encapsulating one or more battery cells. The housing prevents liquids or other foreign matter from affecting the charging or discharging of the battery cells.

[0077] A battery cell includes an electrode assembly and an electrolyte. The electrode assembly consists of a positive electrode, a negative electrode, and a separator. The battery cell primarily functions by the movement of metal ions between the positive and negative electrodes. The positive electrode includes a positive current collector and a positive active material layer. The positive active material layer is coated on the surface of the positive current collector, and the uncoated positive current collector protrudes beyond the coated one, serving as the positive electrode tab. Taking a lithium-ion battery as an example, the positive current collector can be made of aluminum, and the positive active material can be lithium cobalt oxide, lithium iron phosphate, ternary lithium, or lithium manganese oxide, etc. The negative electrode includes a negative current collector and a negative active material layer. The negative active material layer is coated on the surface of the negative current collector, and the uncoated negative current collector protrudes beyond the coated one, serving as the negative electrode tab. The negative electrode current collector can be made of copper, and the negative electrode active material can be carbon or silicon, etc. To ensure that a large current can pass through without melting, there are multiple positive electrode tabs stacked together, and there are multiple negative electrode tabs stacked together. The separator can be made of PP (polypropylene) or PE (polyethylene), etc. In addition, the electrode assembly can be a wound structure or a stacked structure, and the embodiments of this application are not limited to these.

[0078] For a typical battery cell, the electrode assembly needs to be electrically connected to the casing so that the casing can serve as the positive or negative output electrode of the battery cell. Currently, it is not convenient to achieve an electrical connection between the electrode assembly and the casing.

[0079] The inventors discovered that in a single battery cell, since the casing is a hollow structure with an open top, the electrode assembly is electrically connected to the casing by welding the bottom wall of the casing to the electrode assembly from the outside of the casing. However, since the electrode assembly is located inside the casing, it is impossible to determine the welding condition between the electrode assembly and the bottom wall of the casing, making it inconvenient to achieve the electrical connection between the electrode assembly and the casing.

[0080] In view of this, the present application provides a battery cell in which a current collector is disposed on the side of the electrode assembly facing the end cover, the electrode assembly and the housing are electrically connected through the current collector, the end cover is closed to the opening of the housing, and the end cover and the housing are sealed together.

[0081] In such a battery cell, the current collector is used to connect the electrode assembly to the casing. When assembling the battery cell, the current collector can be connected to the casing from inside the casing. After connecting the current collector to the electrode assembly and the casing, the end cap is then closed onto the opening of the casing and sealed to the casing, making the electrical connection between the electrode assembly and the casing more convenient.

[0082] The battery cells described in the embodiments of this application are applicable to batteries and electrical devices that use batteries.

[0083] Electrical equipment can include vehicles, mobile phones, portable devices, laptops, ships, spacecraft, electric toys, and power tools, 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 ship toys, and 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. This application does not impose any special limitations on the above-mentioned electrical equipment.

[0084] For ease of explanation, the following embodiments use a vehicle as an example of electrical equipment.

[0085] Please refer to Figure 1 , Figure 1 The diagram below illustrates the structure of a vehicle 1000 according to some embodiments of this application. A battery 100 is disposed inside the vehicle 1000, and the battery 100 may be located at the bottom, front, or rear of the vehicle 1000. The battery 100 can be used to power the vehicle 1000; for example, the battery 100 can serve as the operating power source for the vehicle 1000.

[0086] The vehicle 1000 may also include a controller 200 and a motor 300. The controller 200 is used to control the battery 100 to supply power to the motor 300, for example, for the power needs of the vehicle 1000 during startup, navigation and driving.

[0087] In some embodiments of this application, the battery 100 can not only serve as the operating power source for the vehicle 1000, but also as the driving power source for the vehicle 1000, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1000.

[0088] In some embodiments, please refer to Figure 2 , Figure 2 The diagram below illustrates the structure of a battery 100 according to some embodiments of this application. The battery 100 includes multiple battery cells 10. The multiple battery cells 10 can be connected in series, in parallel, or in a mixed configuration. A mixed configuration means that some of the multiple battery cells 10 are connected in series and others in parallel.

[0089] In some embodiments, the battery 100 may further include a busbar component, through which multiple battery cells 10 can be electrically connected to each other to achieve series, parallel, or mixed connection of multiple battery cells 10.

[0090] Busbar components can be metallic conductors, such as copper, iron, aluminum, steel, aluminum alloys, etc.

[0091] In some embodiments, the battery cell 10 may further include a housing 20 for accommodating the battery cell 10. The housing 20 may include a first portion 21 and a second portion 22, which overlap each other to define a receiving space for accommodating the battery cell 10. Of course, the connection between the first portion 21 and the second portion 22 may be sealed using a sealing element, such as a sealing ring, sealant, etc.

[0092] The first part 21 and the second part 22 can be of various shapes, such as cuboids or cylinders. The first part 21 can be a hollow structure with one open side, and the second part 22 can also be a hollow structure with one open side. The open side of the second part 22 covers the open side of the first part 21, thus forming a box 20 with a storage space. Alternatively, the first part 21 can be a hollow structure with one open side, and the second part 22 can be a plate-like structure. The second part 22 covers the open side of the first part 21, thus forming a box 20 with a storage space.

[0093] Please refer to Figure 3 , Figure 3 The exploded view of a battery cell 10 provided in some embodiments of this application shows that the battery cell 10 may include a housing 11, an electrode assembly 12, an end cap 13, a current collector 14, and a seal 15.

[0094] The housing 11 is a component used to house the electrode assembly 12. The housing 11 can be a hollow structure with an opening at one end, or it can be a hollow structure with openings at both ends. The housing 11 can be made of various materials, such as copper, iron, aluminum, steel, or aluminum alloy. The housing 11 can also be in various shapes, such as a cylinder or a cuboid. For example, in... Figure 3 In the middle, the shell 11 is a cylinder. Figure 3 The battery cell 10 shown is a cylindrical battery 100.

[0095] Electrode assembly 12 is a component in the battery cell 10 where electrochemical reactions occur. Electrode assembly 12 may include a main body and tabs, with the tabs extending from the main body and protruding from the end of the main body. The main body may include a positive electrode, a negative electrode, and a separator. The main body may be a wound structure formed by winding the positive electrode, separator, and negative electrode. The main body may also be a stacked structure formed by arranging the positive electrode, separator, and negative electrode in layers.

[0096] The positive electrode includes a positive current collector and positive active material layers coated on opposite sides of the positive current collector. The negative electrode includes a negative current collector and negative active material layers coated on opposite sides of the negative current collector. The main body is the portion of the electrode assembly 12 corresponding to the area of ​​the electrode coated with the active material layer, and the tabs are the portions of the electrode not coated with the active material layer. The tabs can be divided into positive tabs and negative tabs, which protrude from both ends of the main body.

[0097] End cap 13 is a component that closes onto the opening of housing 11 to isolate the internal environment of battery cell 10 from the external environment. End cap 13 closes onto the opening of housing 11, and end cap 13 and housing 11 together define a sealed space for accommodating electrode assembly 12, electrolyte, and current collector 14. The shape of end cap 13 can be adapted to the shape of housing 11. For example, if housing 11 is a cuboid structure, end cap 13 can be a rectangular plate structure adapted to housing 11; or if housing 11 is a cylindrical structure, end cap 13 can be a circular plate structure adapted to housing 11. The material of end cap 13 can also be various. End cap 13 can be made of metal, such as copper, iron, aluminum, steel, aluminum alloy, etc. The material of end cap 13 can be the same as or different from the material of housing 11.

[0098] In the battery cell 10, there can be one or two end caps 13. If the housing 11 is a hollow structure with an opening at one end, one end cap 13 is provided accordingly; if the housing 11 is a hollow structure with openings at both ends, two end caps 13 are provided accordingly. The two end caps 13 respectively cover the two openings of the housing 11. One of the positive and negative electrode tabs of the electrode assembly 12 is electrically connected to one end cap 13, and the other is electrically connected to the housing 11. In the embodiment where the housing 11 is a hollow structure with an opening at one end, an electrode terminal 16 can be provided at the end of the housing 11 opposite to the end cap 13. Figure 3 (Not shown), the electrode terminal 16 is insulated from the housing 11, and one of the positive and negative electrodes of the electrode assembly 12 is electrically connected to the housing 11, and the other is electrically connected to the electrode terminal 16.

[0099] The current collector 14 is a component that connects the housing 11 and the electrode assembly 12 to achieve an electrical connection between the electrode assembly 12 and the housing 11, so that the housing 11 serves as an output terminal of the battery cell 10. In embodiments where the electrode assembly 12 is electrically connected to the electrode terminal 16, the positive or negative electrode tab in the electrode assembly 12 can also be electrically connected to the electrode terminal 16 through a current collector 14. For example, the negative electrode tab of the electrode assembly 12 is electrically connected to the housing 11 through a current collector 14, and the positive electrode tab of the electrode assembly 12 is electrically connected to the electrode terminal 16 through another current collector 14.

[0100] The current collector 14 can be a metallic conductor, such as copper, iron, aluminum, steel, aluminum alloy, etc.

[0101] The seal 15 is disposed between the end cap 13 and the housing 11 to achieve a sealed connection between the end cap 13 and the housing 11. The seal 15 can be made of various materials, such as rubber or plastic.

[0102] Please refer to Figure 4 , Figure 4 for Figure 3 The diagram shows a cross-sectional view of a battery cell 10. This embodiment of the application provides a battery cell 10, which includes a housing 11, an electrode assembly 12, an end cap 13, and a current collector 14. The housing 11 has an opening. The electrode assembly 12 is housed within the housing 11. The end cap 13 closes to the opening and is sealed to the housing 11. The current collector 14 is housed within the housing 11 and located on the side of the electrode assembly 12 facing the end cap 13. The current collector 14 is configured to connect the housing 11 and the electrode assembly 12, thereby electrically connecting the electrode assembly 12 to the housing 11.

[0103] The current collector 14 is a component that enables the electrical connection between the electrode assembly 12 and the housing 11. The current collector 14 is connected to both the electrode assembly 12 and the housing 11. The connection between the current collector 14 and the electrode assembly 12 can be either a connection between the current collector 14 and the positive electrode tab of the electrode assembly 12, or a connection between the current collector 14 and the electrode assembly 12 can be such that they are fixed together, for example, by welding the current collector 14 to the positive or negative electrode tab of the electrode assembly 12, or simply a contact between the current collector 14 and the positive or negative electrode tab of the electrode assembly 12. Similarly, the connection between the current collector 14 and the housing 11 can be such that they are fixed together, for example, by welding the current collector 14 to the housing 11, or simply a contact between the current collector 14 and the housing 11.

[0104] In this embodiment, the current collector 14 is located on the side of the electrode assembly 12 facing the end cap 13. The electrode assembly 12 and the housing 11 are electrically connected through the current collector 14. The end cap 13 covers the opening of the housing 11 and is sealed to the housing 11. In this structure, the battery cell 10 realizes the electrical connection between the electrode assembly 12 and the housing 11 through the current collector 14. The current collector 14 can be connected to the housing 11 from the inside of the housing 11. After connecting the current collector 14 to the electrode assembly 12 and the housing 11, the end cap 13 is then covered to the opening of the housing 11 and sealed to the housing 11, making the electrical connection between the electrode assembly 12 and the housing 11 more convenient.

[0105] For a typical battery cell 10, since the bottom wall of the casing 11 is welded to the electrode tab, the bottom wall of the casing 11 is prone to being punctured during the welding process, leading to leakage and affecting the performance of the battery cell 10. However, in this embodiment, the electrode assembly 12 is electrically connected to the casing 11 through the current collector 14, and the end cap 13 is sealed to the casing 11. The electrode assembly 12 is not directly connected to the end cap 13, making it less likely for the battery cell 10 to leak from the end cap 13 side.

[0106] For example, the current collector 14 connects the housing 11 and the negative electrode tab of the electrode assembly 12, so that the housing 11 serves as the negative output electrode of the battery cell 10. The electrode terminal 16 at the end of the housing 11 away from the end cap 13 is electrically connected to the positive electrode tab of the electrode assembly 12, so that the electrode terminal 16 serves as the positive output electrode of the battery cell 10.

[0107] In some embodiments, the current collector 14 is welded to the housing 11. The connection between the current collector 14 and the housing 11 is simple, which can improve the robustness of the connection between the current collector 14 and the housing 11 and achieve stable current flow between the current collector 14 and the housing 11.

[0108] When welding the current collector 14 to the housing 11, the welding can be performed on the outside of the housing 11, for example, by using a through-welding method to weld the current collector 14 to the housing 11 from the outside; alternatively, the current collector 14 can be welded to the housing 11 from the inside. If the welding is performed on the outside of the housing 11, the weld portion 17 formed after welding the current collector 14 to the housing 11 is located on the outside of the housing 11; if the welding is performed on the inside of the housing 11, the weld portion 17 formed after welding the current collector 14 to the housing 11 is located inside the housing 11.

[0109] In some embodiments, the current collector 14 is welded to the housing 11 to form a welded portion 17, which is used to fix the current collector 14 and the housing 11. The welded portion 17 is located inside the housing 11.

[0110] The welding part 17 serves to fix the current collector 14 and the housing 11, that is, the current collector 14 is fixed to the housing 11 through the welding part 17. The welding part 17 can be solder connecting the current collector 14 and the housing 11, or it can be a fusion part where the current collector 14 and the housing 11 are fused together.

[0111] Taking the shell 11 as an example, if the welded part 17 formed by welding the current collector 14 and the shell 11 is located outside the shell 11, the outer protective layer of the shell 11 is easily damaged during the welding process of the current collector 14 and the shell 11, and corrosion is likely to occur.

[0112] In this embodiment, the welded part 17 formed by welding the current collector 14 and the housing 11 is located inside the housing 11, which reduces the risk of damage to the outer structure of the housing 11 caused by the welded part 17 being located outside the housing 11 during the welding process of the current collector 14 and the housing 11, reduces the risk of corrosion of the housing 11, and improves the service life of the battery cell 10.

[0113] In some embodiments, please continue to refer to Figure 4 The inner side 111 of the housing 11 is provided with a first limiting part 112, which is used to limit the movement of the end cap 13 in the direction facing the electrode assembly 12. The current collector 14 is welded to the first limiting part 112.

[0114] The inner surface 111 of the housing 11 refers to the inner surface of the sidewall of the housing 11 extending along the thickness direction Z of the end cap 13. The first limiting part 112 is a structure that protrudes from the inner surface 111 of the housing 11 and restricts the movement of the end cap 13 in the direction facing the electrode assembly 12. The first limiting part 112 and the housing 11 can be integrally formed or they can be separately formed and then connected together.

[0115] In this embodiment, the first limiting part 112 limits the end cap 13, restricting its movement in the direction facing the electrode assembly 12. The current collector 14 is welded to the first limiting part 112, which effectively utilizes the first limiting part 112, facilitating the welding and fixing of the current collector 14.

[0116] In some embodiments, please refer to Figure 5 , Figure 5 This is a partial view of a battery cell 10 provided in some embodiments of this application. The current collector 14 includes a body portion 141 for connection to the electrode assembly 12. The body portion 141 is located on the side of the first limiting portion 112 facing the electrode assembly 12. The first limiting portion 112 is used to restrict the body portion 141 from detaching from the housing 11 in a direction away from the electrode assembly 12.

[0117] The body portion 141 is the part where the current collector 14 connects to the electrode assembly 12; for example, the body portion 141 is welded to the negative electrode tab of the electrode assembly 12. The current collector 14 can be entirely comprised of the body portion 141, or a portion of the current collector 14 can be the body portion 141. For example, in... Figure 5 In the middle, the flow collection component 14 is the whole body part 141.

[0118] The first limiting part 112 limits the main body part 141. The first limiting part 112 can restrict the main body part 141 from detaching from the housing 11 in the direction away from the electrode assembly 12. The first limiting part 112 can separate the end cover 13 and the main body part 141. The main body part 141 is less likely to affect the seal between the end cover 13 and the housing 11, thereby improving the sealing performance between the end cover 13 and the housing 11.

[0119] In some embodiments, please continue to refer to Figure 5 The main body 141 abuts against the side of the first limiting part 112 facing the electrode assembly 12 and is welded to the first limiting part 112.

[0120] The main body 141 abuts against the side of the first limiting part 112 facing the electrode assembly 12. Understandably, the main body 141 abuts against the end face of the first limiting part 112 facing the electrode assembly 12, and the first limiting part 112 serves to prevent the main body 141 from moving in a direction away from the electrode assembly 12.

[0121] In this embodiment, the main body 141 abuts against the side of the first limiting part 112 facing the electrode assembly 12 and is welded to the first limiting part 112, so that the entire current collector 14 has good firmness after being fixed to the first limiting part 112, increasing the contact area between the current collector 14 and the first limiting part 112, thereby increasing the flow area between the housing 11 and the current collector 14.

[0122] For example, in Figure 5 In the middle, the body part 141 has an outer surface 1412 facing away from the electrode assembly 12 in the thickness direction Z of the end cap 13, the first limiting part 112 has an inner peripheral surface 1121, and the welding part 17 formed by welding the body part 141 and the first limiting part 112 is connected to the outer surface 1412 of the body part 141 and the inner peripheral surface 1121 of the first limiting part 112.

[0123] In some embodiments, please refer to Figure 6 , Figure 6 This is a partial view of a battery cell 10 provided in some embodiments of this application. The current collector 14 may also include an elastic portion 142, which is connected to the body portion 141 and abuts against and is welded to the first limiting portion 112.

[0124] The elastic portion 142 is the part of the current collector 14 connected to the body portion 141 that can undergo elastic deformation. In the thickness direction Z of the end cap 13, the elastic portion 142 is located on the side of the body portion 141 facing the first limiting portion 112. The elastic portion 142 and the body portion 141 can be integrally formed or separately formed and then connected together. There can be one or more elastic portions 142 in the current collector 14. If there are multiple elastic portions 142 in the current collector 14, the multiple elastic portions 142 can be distributed circumferentially around the body portion 141.

[0125] In this embodiment, the elastic portion 142 of the current collector 14 abuts against the first limiting portion 112 and is welded to the first limiting portion 112. The elastic portion 142 can undergo elastic deformation according to the change in distance between the main body portion 141 and the first limiting portion 112, thereby reducing the risk of the electrode assembly 12 moving within the housing 11 due to the vibration of the battery cell 10, which could cause the electrical connection between the main body portion 141 and the electrode assembly 12 to fail.

[0126] In some embodiments, please continue to refer to Figure 6 The elastic part 142 is a spring sheet that is bent and arranged on the body part 141. This elastic part 142 has a simple structure, good deformation ability, and can increase the contact area between the elastic part 142 and the first limiting part 112.

[0127] In other embodiments, the elastic part 142 may also be other structures, such as a spring structure connected to the body part 141.

[0128] In some embodiments, please refer to Figure 7 , Figure 7 for Figure 4 The partial view of the battery cell 10 shown shows that the current collector 14 may also include a first connecting portion 143, which is connected to the body portion 141. The first connecting portion 143 extends at least partially to the inner peripheral side of the first limiting portion 112 and is welded to the first limiting portion 112.

[0129] The first connecting portion 143 is the part where the current collecting member 14 is welded to the first limiting portion 112, and at least a portion of this portion extends to the inner peripheral side of the first limiting portion 112. Taking the first limiting portion 112 having an inner peripheral surface 1121 as an example, the first connecting portion 143 extends at least partially to the inner peripheral side of the first limiting portion 112, that is, the first connecting portion 143 extends at least partially into the space defined by the inner peripheral surface 1121 of the first limiting portion 112.

[0130] In this embodiment, the first connecting part 143 is welded to the first limiting part 112. Since a portion of the first connecting part 143 of the current collecting member 14 extends to the inner circumferential side of the first limiting part 112, the first connecting part 143 and the first limiting part 112 can be directly welded together, reducing the welding difficulty between the current collecting member 14 and the first limiting part 112.

[0131] It should be noted that when the first connecting portion 143 of the current collector 14 is welded to the first limiting portion 112, the body portion 141 of the current collector 14 can abut against the side of the first limiting portion 112 facing the electrode assembly 12, or the body portion 141 can be spaced apart from the first limiting portion 112 in the thickness direction Z of the end cap 13. Figure 7 In the middle, the main body 141 abuts against the side of the first limiting part 112 facing the electrode assembly 12 to increase the flow area between the current collector 14 and the housing 11.

[0132] In some embodiments, please continue to refer to Figure 7 The first connecting portion 143 is a protrusion extending from the body portion 141 in a direction away from the electrode assembly 12, and the protrusion is used to form a positioning engagement with the inner peripheral surface 1121 of the first limiting portion 112.

[0133] The protrusion forms a positioning fit with the inner peripheral surface 1121 of the first limiting part 112, and the outer peripheral surface of the protrusion contacts the inner peripheral surface 1121 of the first limiting part 112 to prevent the protrusion from shaking in the direction perpendicular to the thickness direction Z of the end cover 13.

[0134] In this embodiment, since the first connecting portion 143 is a protrusion that forms a positioning fit with the inner peripheral surface 1121 of the first limiting portion 112, the positioning fit between the protrusion and the inner peripheral surface 1121 of the first limiting portion 112 reduces the risk of the current collecting member 14 shaking during the welding process between the first connecting portion 143 and the first limiting portion 112, reduces the welding difficulty, and improves the firmness of the first connecting portion 143 and the first limiting portion 112 after welding. At the same time, it increases the contact area between the housing 11 and the current collecting member 14, thereby increasing the flow area between the housing 11 and the current collecting member 14.

[0135] In some embodiments, please continue to refer to Figure 7 The body portion 141 has an inner surface 1411 facing the electrode assembly 12 and an outer surface 1412 facing away from the electrode assembly 12, and a protrusion extends from the outer surface 1412 of the body portion 141 in a direction facing away from the electrode assembly 12. The current collector 14 also includes a recess 144, which is recessed from the inner surface 1411 of the body portion 141 in a direction facing away from the electrode assembly 12 toward the protrusion.

[0136] The recess 144 on the collector member 14 reduces the material of the collector member 14 and lowers the manufacturing cost. On the other hand, it improves the deformation capacity of the protrusion, so that the protrusion elastically abuts against the first limiting part 112, and the protrusion and the first limiting part 112 make good contact.

[0137] In some embodiments, both the protrusion and the recess 144 are annular structures extending circumferentially along the first limiting portion 112.

[0138] Both the protrusion and the recess 144 are annular structures, which gives the protrusion better deformation capability. If the protrusion is subjected to a radial force applied by the first limiting part 112, the protrusion can shrink and deform towards the center position, so that the protrusion and the first limiting part 112 form a tighter fit, and the protrusion and the first limiting part 112 make good contact.

[0139] In some embodiments, please continue to refer to Figure 7 In the direction in which the first connecting portion 143 extends from the body portion 141 away from the electrode assembly 12, the end of the first connecting portion 143 away from the body portion 141 does not exceed the first limiting portion 112.

[0140] The end of the first connecting portion 143 that is away from the main body portion 141 does not extend beyond the first limiting portion 112. That is, the end of the first connecting portion 143 that is away from the main body portion 141 is located within the first limiting portion 112. It can be understood that, in the thickness direction Z of the end cap 13, the end of the first connecting portion 143 that is away from the main body portion 141 is closer to the electrode assembly 12 than the end of the first limiting portion 112 that is away from the electrode assembly 12.

[0141] In this embodiment, since the end of the first connecting part 143 that is away from the main body part 141 does not exceed the first limiting part 112, the first connecting part 143 is less likely to interfere with the end cover 13, thereby improving the sealing between the end cover 13 and the housing 11.

[0142] In some embodiments, please continue to refer to Figure 7 The first connecting portion 143 is welded to the inner peripheral surface 1121 of the first limiting portion 112. The inner peripheral surface 1121 of the first limiting portion 112 has a dividing position 1121a. The radial dimension of the inner peripheral surface 1121 of the first limiting portion 112 gradually increases from the dividing position 1121a to both ends of the inner peripheral surface 1121 of the first limiting portion 112. In the direction in which the first connecting portion 143 extends from the body portion 141 in a direction away from the electrode assembly 12, one end of the first connecting portion 143 away from the body portion 141 extends beyond the dividing position 1121a.

[0143] In the above description, the two ends of the inner circumferential surface 1121 refer to the two ends of the inner circumferential surface 1121 in the thickness direction Z of the end cap 13.

[0144] The radial dimension of the inner circumferential surface 1121 of the first limiting portion 112 gradually increases from the dividing position 1121a to both ends of the inner circumferential surface 1121 of the first limiting portion 112, making the inner circumferential surface 1121 of the first limiting portion 112 a constricted structure that is larger at both ends and smaller in the middle. For example, the intersection line of the inner circumferential surface 1121 of the first limiting portion 112 and its axial section is an arc shape, and the axial section is parallel to the thickness direction Z of the end cap 13.

[0145] In this embodiment, since the end of the first connecting part 143 that is away from the main body part 141 extends beyond the dividing position 1121a, a weld seam is formed between the outer peripheral surface of the first connecting part 143 and the inner peripheral surface 1121 of the first limiting part 112, which facilitates welding and fixing the first connecting part 143 and the first limiting part 112.

[0146] For example, in Figure 7 In the process, the welded part 17 formed by welding the first connecting part 143 and the first limiting part 112 is located in the weld seam formed between the first connecting part 143 and the first limiting part 112.

[0147] In some embodiments, please refer to Figure 8 , Figure 8 A partial view of the battery cell 10 provided in some embodiments of this application shows that the first connecting portion 143 may include an extension portion 1431 and a limiting portion 1432. The extension portion 1431 is connected to the body portion 141 and extends from the body portion 141 in a direction away from the electrode assembly 12, extending at least partially to the inner periphery of the first limiting portion 112. The limiting portion 1432 is connected to the extension portion 1431 and abuts against the side of the first limiting portion 112 away from the electrode assembly 12 and is welded to the first limiting portion 112.

[0148] The extension segment 1431 is the portion of the first connecting portion 143 extending into the interior of the first limiting portion 112, and the limiting segment 1432 is the portion where the first connecting portion 143 is welded to the first limiting portion 112. The extension segment 1431 extends at least partially to the inner circumference of the first limiting portion 112, and the limiting segment 1432 abuts against the side of the first limiting portion 112 away from the electrode assembly 12, so that the first connecting portion 143 is hooked onto the first limiting portion 112, thereby causing the body portion 141 of the current collector 14 to tightly abut against the first limiting portion 112. For example, the extension segment 1431 is a cylindrical structure, and the limiting segment 1432 is an annular structure located at the end of the extension segment 1431 away from the body portion 141. The limiting segment 1432 can be welded to the first limiting portion 112 by through welding.

[0149] In this embodiment, the limiting segment 1432 abuts against the side of the first limiting part 112 away from the electrode assembly 12 and is welded to the first limiting part 112. The limiting segment 1432 plays a limiting role, which improves the firmness of the current collector 14 after welding with the first limiting part 112 and increases the contact area between the current collector 14 and the first limiting part 112, thereby increasing the flow area between the housing 11 and the current collector 14.

[0150] In some embodiments, please continue to refer to Figures 5-8 The first limiting part 112 is an annular structure extending circumferentially along the shell 11. This structure makes the first limiting part 112 easy to mold and manufacture, and the first limiting part 112 can restrict the end cover 13 throughout its entire circumference, thus improving the limiting ability of the first limiting part 112 on the end cover 13.

[0151] In some embodiments, a roller groove 113 is provided on the outer side of the housing 11 at a position corresponding to the first limiting portion 112.

[0152] During the formation of the roller groove 113, a first limiting part 112 is formed on the housing 11 at a position corresponding to the roller groove 113, which simplifies the forming process of the first limiting part 112. After the first limiting part 112 is formed by the roller groove 113 process, the radial dimension of the inner peripheral surface 1121 of the first limiting part 112 gradually increases from the dividing position 1121a to both ends of the inner peripheral surface 1121 of the first limiting part 112.

[0153] In an embodiment where the first limiting portion 112 is an annular structure extending circumferentially along the housing 11, the roller groove 113 may also be an annular structure extending axially along the housing 11.

[0154] In some embodiments, the battery cell 10 further includes a seal 15, and the end cap 13 and the housing 11 are sealed together by the seal 15 to improve the sealing performance of the end cap 13 and the housing 11.

[0155] The seal 15 can be made of materials such as rubber or plastic.

[0156] In some embodiments, the seal 15 is configured to insulate the housing 11 from the end cap 13. The seal 15 serves both as a seal and an insulator between the housing 11 and the end cap 13, improving the sealing performance between the end cap 13 and the housing 11 while reducing the risk of the end cap 13 becoming electrified.

[0157] In some embodiments, the seal 15 is configured to circumferentially cover the end cap 13 along the opening of the housing 11. This structure improves the sealing performance of the seal 15 on the end cap 13 and the housing 11, and also enhances the overall integrity of the seal 15 and the housing 11. During the assembly of the battery cell 10, the seal 15 can be first covered on the end cap 13, and then the end cap 13 and the seal 15 can be installed as a whole on the housing 11.

[0158] In some embodiments, the housing 11 has a second limiting portion 114 at one end of the opening, which is used to restrict the end cap 13 from disengaging from the housing 11 in a direction away from the electrode assembly 12. In the thickness direction Z of the end cap 13, at least a portion of the sealing member 15 is located between the end cap 13 and the second limiting portion 114 to achieve a sealed connection between the end cap 13 and the housing 11.

[0159] The second limiting part 114 restricts the end cap 13, preventing it from detaching from the housing 11 in the direction away from the electrode assembly 12. The second limiting part 114 and the first limiting part 112 cooperate to restrict the movement of the end cap 13 in the thickness direction Z of the end cap 13, thereby confining the end cap 13 to the end of the housing 11 with an opening. Since at least a portion of the sealing member 15 is located between the end cap 13 and the second limiting part 114, a sealed connection is achieved between the end cap 13 and the housing 11, improving the sealing performance between the end cap 13 and the housing 11.

[0160] For example, the second limiting part 114 can be a flange structure in which the housing 11 is partially folded inward. By folding the housing 11, the second limiting part 114 can be formed at the opening of the housing 11. During the assembly of the battery cell 10, the electrode assembly 12 and the current collector 14 can be accommodated in the housing 11 first, and then the housing 11 can be processed with a roller groove 113 to form the first limiting part 112. Then, the end cap 13 and the sealing member 15 are abutted against the first limiting part 112 as a whole. Finally, the second limiting part 114 is formed by folding the housing 11 to restrict the end cap 13.

[0161] In some embodiments, the seal 15 includes a housing 151 and a second connecting portion 152 connected to the housing 151. At least a portion of the end cap 13 is located within the housing 151. In the thickness direction Z of the end cap 13, the second connecting portion 152 is located between the end cap 13 and the second limiting portion 114 to achieve a sealed connection between the end cap 13 and the housing 11.

[0162] The enclosure 151 surrounds the outer periphery of the end cap 13, so that the sealing element 15 covers the end cap 13 circumferentially along the opening of the housing 11. For example, the end cap 13 presses the enclosure 151 against the inner side 111 of the housing 11, and both the enclosure 151 and the second connecting part 152 serve a sealing function.

[0163] In this embodiment, since at least a portion of the end cap 13 is located inside the enclosure 151, and the second connecting portion 152 is located between the end cap 13 and the second limiting portion 114, the sealing member 15 has a simple structure. While achieving a good seal between the end cap 13 and the housing 11, it also ensures that the sealing member 15 and the end cap 13 have good integrity.

[0164] In some embodiments, the seal 15 may further include a third connecting portion 153, which is connected to the enclosure 151 and abuts against the first limiting portion 112. The third connecting portion 153 and the second connecting portion 152 abut against the two ends of the end cap 13 in the thickness direction Z, so that the seal 15 cannot move relative to the end cap 13 in the thickness direction Z, and the seal 15 and the end cap 13 have good integrity.

[0165] For example, both the first connecting portion 143 and the second connecting portion 152 are annular structures.

[0166] Furthermore, this application provides a battery 100, which includes a plurality of battery cells 10 provided in any of the above embodiments.

[0167] This application provides an electrical device, including a battery cell 10 provided in any of the above embodiments.

[0168] The electrical equipment can be any of the devices that use battery 100 as described above.

[0169] Additionally, please combine Figure 4 and Figure 7 This application also provides a battery cell 10, including a housing 11, an electrode assembly 12, an end cap 13, and a current collector 14. The housing 11 has an opening, and a roller groove 113 is provided on the outer side of the housing 11. A first limiting portion 112 protruding from the inner side 111 of the housing 11 is formed at a position corresponding to the roller groove 113. The electrode assembly 12 has a negative electrode tab and a positive electrode tab, and is housed within the housing 11. The end cap 13 covers the opening of the housing 11 and is sealed to the housing 11. The first limiting portion 112 restricts the end cap 13 from moving in the direction facing the electrode assembly 12. The current collector 14 is configured to connect the negative electrode tab and the housing 11, so that the electrode assembly 12 is electrically connected to the housing 11. An electrode terminal 16 is provided at the end of the housing 11 away from the end cap 13, and the electrode terminal 16 is electrically connected to the positive electrode tab.

[0170] The current collector 14 includes a body portion 141 and a first connecting portion 143. The body portion 141 is located on the side of the first limiting portion 112 facing the electrode assembly 12 and abuts against the first limiting portion 112. The first connecting portion 143 is connected to the body portion 141 and extends to the inner circumferential side of the first limiting portion 112. The first connecting portion 143 forms a positioning fit with the inner circumferential surface 1121 of the first limiting portion 112, and the first connecting portion 143 is welded to the inner circumferential surface 1121 of the first limiting portion 112. The inner circumferential surface 1121 of the first connecting portion 143 has a dividing position 1121a, and the radial dimension of the inner circumferential surface 1121 gradually increases from the dividing position 1121a to both ends of the inner circumferential surface 1121. In the direction in which the first connecting portion 143 extends from the body portion 141 away from the electrode assembly 12, one end of the first connecting portion 143 away from the body portion 141 extends beyond the boundary position 1121a but does not extend beyond the first limiting portion 112. The body portion 141 has an inner surface 1411 facing the electrode assembly 12 and an outer surface 1412 away from the electrode assembly 12. The first connecting portion 143 is a protrusion extending from the outer surface 1412 of the body portion 141 away from the electrode assembly 12. The current collecting member 14 is provided with a recess 144, which is recessed from the inner surface 1411 of the body portion 141 in the direction away from the electrode assembly 12 toward the protrusion. Both the protrusion and the recess 144 are annular structures extending circumferentially along the first limiting portion 112.

[0171] In such a battery cell 10, the current collector 14 can be easily welded to the housing 11 before the end cap 13 is closed on the opening of the housing 11, thereby facilitating the electrical connection between the electrode assembly 12 and the housing 11, so that the current collector 14 and the housing 11 have stable large-area current flow, improving the performance of the battery cell 10.

[0172] This application provides a method for manufacturing a battery cell 10. Please refer to... Figure 9 , Figure 9 This is a flowchart of a method for manufacturing a battery cell 10 according to some embodiments of this application. The manufacturing method includes:

[0173] S100: A housing 11 is provided, the housing 11 having an opening;

[0174] S200: Provides electrode assembly 12;

[0175] S300: End cap 13 is provided;

[0176] S400: Provides a current collection component 14;

[0177] S500: Connect the current collector 14 to the electrode assembly 12;

[0178] S600: The electrode assembly 12 and the current collector 14 are housed within the housing 11;

[0179] S700: Cover the end cap 13 with the opening of the housing 11 and seal the end cap 13 with the housing 11 so that the current collector 14 is located on the side of the electrode assembly 12 facing the end cap 13.

[0180] The housing 11 and the electrode assembly 12 are electrically connected through the current collector 14.

[0181] In the above method, the order of steps S100, S200, S300 and S400 is not restricted. For example, step S400 can be executed first, then step S300, then step S200, and then step S100.

[0182] It should be noted that the relevant structure of the battery cell 10 manufactured by the manufacturing method provided in the above embodiments can be found in the battery cell 10 provided in the foregoing embodiments, and will not be repeated here.

[0183] In some embodiments, before closing the end cap 13 to the opening, the manufacturing method further includes welding the current collector 14 to the housing 11 from the inside of the housing 11.

[0184] This application also provides a manufacturing apparatus 2000 for a battery cell 10, please refer to... Figure 10 , Figure 10 This is a schematic diagram of the structure of a manufacturing apparatus 2000 for a battery cell 10 provided in some embodiments of this application. The manufacturing apparatus 2000 includes a first supply device 2100, a second supply device 2200, a third supply device 2300, a fourth supply device 2400, and an assembly device 2500.

[0185] A first providing device 2100 provides a housing 11 having an opening. A second providing device 2200 provides an electrode assembly 12. A third providing device 2300 provides an end cap 13. A fourth providing device 2400 provides a current collector 14. An assembly device 2500 connects the current collector 14 to the electrode assembly 12; the assembly device 2500 also accommodates the electrode assembly 12 and the current collector 14 within the housing 11; the assembly device 2500 further closes the end cap 13 to the opening and seals the end cap 13 to the housing 11, such that the current collector 14 is located on the side of the electrode assembly 12 facing the end cap 13. The housing 11 and the electrode assembly 12 are electrically connected via the current collector 14.

[0186] It should be noted that the relevant structure of the battery cell 10 manufactured by the manufacturing equipment 2000 provided in the above embodiments can be found in the battery cell 10 provided in the foregoing embodiments, and will not be repeated here.

[0187] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other.

[0188] The above embodiments are only used to illustrate the technical solutions of this application and are not intended to limit this application. For those skilled in the art, this application can have various modifications and variations. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A battery cell, characterized by, The application relates to a shell, an electrode assembly, an end cover and a current collecting member. The shell has an opening and is in a cylindrical shape. The electrode assembly is accommodated in the shell. The end cover covers the opening and is in a circular plate shape matching the shell. The current collecting member is accommodated in the shell and located on the side of the electrode assembly facing the end cover. The current collecting member is welded to the shell to electrically connect the electrode assembly and the shell. The current collecting member is welded to the shell to form a welding part for fixing the current collecting member and the shell.

2. The battery cell of claim 1, wherein, The inner side of the shell is provided with a first limiting part for limiting the movement of the end cover in the direction facing the electrode assembly. The current collecting member is welded to the first limiting part.

3. The battery cell of claim 2, wherein, The current collecting member comprises a body part connected to the electrode assembly. The body part is located on the side of the first limiting part facing the electrode assembly.

4. The battery cell of claim 3, wherein, The body part is welded to the side of the first limiting part facing the electrode assembly.

5. The battery cell of claim 3, wherein, The current collecting member further comprises an elastic part connected to the body part. The elastic part is a spring arranged on the body part.

6. The battery cell of claim 5, wherein, The current collecting member further comprises a first connecting part connected to the body part.

7. The battery cell of claim 3, wherein, The first connecting part at least partially extends to the inner circumferential side of the first limiting part. The first connecting part is a protruding part extending from the body part in the direction away from the electrode assembly.

8. The battery cell of claim 7, wherein, The protruding part is used to form a positioning fit with the inner circumferential surface of the first limiting part.

9. The battery cell of claim 8, wherein, The body part has an inner surface facing the electrode assembly and an outer surface away from the electrode assembly. The protruding part is recessed from the inner surface in the direction away from the electrode assembly. The protruding part and the recess are both annular structures extending along the circumference of the first limiting part.

10. The battery cell of claim 9, wherein, In the direction of the first connecting part extending from the body part in the direction away from the electrode assembly, the end of the first connecting part away from the body part does not exceed the first limiting part.

11. The battery cell of claim 7, wherein, The first connecting part is welded to the inner circumferential surface of the first limiting part.

12. The battery cell of claim 7, wherein, The inner circumferential surface has a boundary position. In the direction of the first connecting part extending from the body part in the direction away from the electrode assembly, the end of the first connecting part away from the body part exceeds the boundary position.

13. The battery cell of claim 7, wherein, The first connecting part comprises an extension segment connected to the body part. The extension segment extends from the body part in the direction away from the electrode assembly. The extension segment at least partially extends to the inner circumferential side of the first limiting part. A limiting section is connected to the extending section, and the limiting section abuts against a side of the first limiting part away from the electrode assembly and is welded with the first limiting part.

14. The battery cell of claim 2, wherein, The first limiting part is an annular structure extending along the circumference of the shell.

15. The battery cell of claim 2, wherein, An outer side surface of the shell is provided with a roller groove at a position corresponding to the first limiting part.

16. The battery cell of any one of claims 1-15, wherein, The battery monomer further comprises a sealing member; The end cover is sealingly connected with the shell through the sealing member.

17. The battery cell of claim 16, wherein, The sealing member is configured to insulate and isolate the shell and the end cover.

18. The battery cell of claim 16, wherein, The sealing member is configured to wrap the end cover along the circumference of the opening.

19. The battery cell of claim 16, wherein, The shell is provided with a second limiting part at one end of the opening, and the second limiting part is used to limit the end cover from being separated from the shell in a direction away from the electrode assembly. In the thickness direction of the end cover, at least a part of the sealing member is located between the end cover and the second limiting part to achieve the sealing connection between the end cover and the shell.

20. The battery cell of claim 19, wherein, The sealing member comprises a surrounding body and a second connecting part connected to the surrounding body. At least a part of the end cover is located in the surrounding body, and in the thickness direction of the end cover, the second connecting part is located between the end cover and the second limiting part to achieve the sealing connection between the end cover and the shell.

21. A battery, characterized by The battery monomer comprises a plurality of battery monomers according to any one of claims 1-20.

22. An electrical device, comprising: The battery monomer comprises a plurality of battery monomers according to any one of claims 1-20.

23. A method of manufacturing a battery cell, characterized by, The battery monomer comprises: A shell is provided, the shell has an opening, and the shell is a cylinder; An electrode assembly is provided; An end cover is provided, the end cover is a circular plate structure matched with the shell; A current collecting member is provided; The current collecting member is connected to the electrode assembly; The electrode assembly and the current collecting member are contained in the shell; The end cover is covered on the opening, and the end cover is sealingly connected with the shell, so that the current collecting member is located on a side of the electrode assembly facing the end cover; The shell and the electrode assembly are electrically connected through the current collecting member, the current collecting member is welded to the shell, the current collecting member and the shell are welded to form a welding part, the welding part is used to fix the current collecting member and the shell, the welding part is located in the interior of the shell, and does not penetrate through the outer side surface of the shell.

24. The manufacturing method according to claim 23, wherein, Before the end cover is covered on the opening, the manufacturing method further comprises: The current collecting member is welded to the shell from the interior of the shell.

25. A manufacturing apparatus of a battery cell, characterized by, The battery monomer comprises: A first providing device is used to provide a shell, the shell has an opening, and the shell is a cylinder; A second providing device is used to provide an electrode assembly; A third providing device is used to provide an end cover, the end cover is a circular plate structure matched with the shell; A fourth providing device is used to provide a current collecting member; An assembling device is used to connect the current collecting member to the electrode assembly, to contain the electrode assembly and the current collecting member in the shell, and to cover the end cover on the opening and sealingly connect the end cover with the shell, so that the current collecting member is located on a side of the electrode assembly facing the end cover. The shell and the electrode assembly are electrically connected through the current collecting member, the current collecting member is welded with the shell to form a welding portion, the welding portion is used for fixing the current collecting member and the shell, the welding portion is located in the interior of the shell, and does not penetrate through the outer side surface of the shell.

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