Cylindrical battery cell and processing method therefor, battery device, and electric device

Abstract

The present application is applicable to the technical field of batteries, and provides a cylindrical battery cell (10), a battery device, and an electric device (2000). The cylindrical battery cell (10) comprises a casing (2) and an electrode assembly (1) arranged in the casing (2). The electrode assembly (1) comprises a first electrode sheet (11a) and a second electrode sheet (11b), and the first electrode sheet (11a) and the second electrode sheet (11b) each comprise a current collector body (1111), a tab (1112) and a film layer (112). On the side where the tab (1112) of the first electrode sheet (11a) is located, the film layer (112) of the first electrode sheet (11a) exceeds an end portion of the second electrode sheet (11b), and the distance between an end portion of the film layer (112) of the first electrode sheet (11a) and the end portion of the second electrode sheet (11b) is greater than or equal to 0.3 mm. In this way, the problem of an internal short circuit of the electrode assembly (1) caused by bending of the tabs (1112) can be alleviated.

Description

Cylindrical battery cells and their processing methods, battery devices and electrical devices

[0001] Cross-referencing

[0002] This application claims priority to international patent application filed on January 26, 2025, in China, application number PCT / CN2025 / 075108, entitled "Cylindrical battery cell and processing method thereof, battery device and power supply device", the entire contents of which are incorporated herein by reference. Technical Field

[0003] This application relates to the field of battery technology, specifically to a cylindrical battery cell and its processing method, a battery device, and an electrical device. Background Technology

[0004] From a market perspective, the application of battery devices is becoming increasingly widespread. Battery devices are not only used in energy storage systems such as hydropower, thermal power, wind power, and solar power plants, but also extensively in electric vehicles such as electric bicycles, electric motorcycles, and electric cars, as well as in military equipment and aerospace. As the application areas of battery devices continue to expand, the market demand is also constantly increasing, and the capacity of battery devices is becoming larger, while the performance requirements for battery devices are also becoming more stringent.

[0005] In related technologies, battery devices typically include one or more battery cells. For cylindrical battery cells, the tabs are generally all tabs. After the electrode sheets are wound, the tabs can be bent, and then the two ends of the electrode assembly are squeezed to compress the tabs.

[0006] During the bending process, numerous bends are formed on the tabs. During compression, the tabs are subjected to pressure moving towards the main body of the electrode assembly, causing them to move along these bends towards the main body. This makes it easy for the tabs to insert into the main body, creating a significant risk of short circuits between the positive and negative electrodes, thus affecting the reliability of the cylindrical battery cell.

[0007] The above statements are for the purpose of providing background information in relation to this application only and do not necessarily constitute prior art. Summary of the Invention

[0008] In view of the above problems, the purpose of this application is to provide a cylindrical battery cell and its processing method, battery device and power device, which can improve the technical problem of short electrode assembly caused by tab bending.

[0009] The technical solution adopted in the embodiments of this application is:

[0010] In a first aspect, embodiments of this application provide a cylindrical battery cell, comprising:

[0011] shell;

[0012] An electrode assembly is at least partially disposed within a housing. The electrode assembly has a wound structure and includes a first electrode and a second electrode with opposite polarities. Both the first electrode and the second electrode include a current collector and a film layer disposed on the current collector. The current collector includes a current collector body and an electrode tab arranged along a first direction. The film layer is disposed on the current collector body. The portion of the current collector extending beyond the film layer along the first direction is the electrode tab. The electrode tab is bent and disposed. The electrode tabs of the first electrode and the second electrode are respectively disposed at both ends of the electrode assembly along the first direction.

[0013] Wherein, on the side where the tab of the first electrode is located, the film layer of the first electrode extends beyond the end of the second electrode along the first direction, and the distance between the end of the film layer of the first electrode and the end of the second electrode is H1, where H1≥0.3mm.

[0014] The cylindrical battery cell provided in this application embodiment has a larger distance between the ends of the first electrode film and the second electrode on the side where the first electrode tab is located, by having the first electrode tab extend beyond the end of the second electrode along a first direction, and the distance between the end of the first electrode film and the end of the second electrode being ≥0.3mm. This ensures that after the tab is compressed, even after the first electrode tab moves towards the second electrode along the bending position, a certain safe distance remains between the first electrode tab and the second electrode, thus mitigating the problem of short circuits in the electrode assembly caused by overlap between the first and second electrode tabs.

[0015] In some embodiments, H1 ≥ 0.5 mm.

[0016] This design helps to improve the problem of the first electrode tab bending along the bend and overlapping with the second electrode, which causes internal shorting of the electrode assembly, thereby helping to improve the reliability of the cylindrical battery cell.

[0017] In some embodiments, the first electrode is a positive electrode. In the positive electrode, the film layer includes a first active material layer and an insulating layer. Both the first active material layer and the insulating layer are disposed on the current collector. In a first direction, at least a portion of the insulating layer is disposed between the tab and the first active material layer.

[0018] This configuration results in a larger distance between the tab of the positive electrode and the negative electrode in the first direction. This helps to improve the problem of overlap between the tab of the positive electrode and the negative electrode when the tab of the positive electrode is inserted into the main body along the bending position.

[0019] In some embodiments, in the positive electrode sheet, the tensile strength of the combined structure of the insulating layer and the current collector is greater than the tensile strength of the tab.

[0020] In this way, after the tab is bent, the combined structure of the insulation layer and the current collector body can have a large pressure resistance and is not easy to bend during the compression process. Thus, after the compression process, a large safety distance can still be maintained between the tab of the positive electrode and the negative electrode. This can effectively improve the problem of the tab of the positive electrode bending towards the body along the bending position during the compression process and overlapping the negative electrode. This can effectively improve the problem of the electrode assembly being short due to the tab bending setting.

[0021] In some embodiments, in the positive electrode sheet, the tensile strength of the combined structure of the insulating layer and the current collector is greater than 1.5 times the tensile strength of the tab.

[0022] In this way, the combined structure of the insulating layer and the current collector has high tensile strength, enabling it to withstand greater pressure and resist bending. Therefore, even after the tab compression process, a large safety distance can still be maintained between the positive electrode tab and the negative electrode, effectively mitigating the problem of the positive electrode tab bending towards the main body along the bending point during compression and overlapping the negative electrode. This effectively addresses the issue of the electrode assembly being internally short due to the tab bending design.

[0023] In some embodiments, in the positive electrode sheet, the tensile strength of the combined structure of the insulating layer and the current collector is greater than or equal to 600 MPa.

[0024] In this way, the combined structure of the insulating layer and the current collector has high tensile strength, enabling it to withstand greater pressure and resist bending. Therefore, even after the tab compression process, a large safety distance can still be maintained between the positive electrode tab and the negative electrode, effectively mitigating the problem of the positive electrode tab bending towards the main body along the bending point during compression and overlapping the negative electrode. This effectively addresses the issue of the electrode assembly being internally short due to the tab bending design.

[0025] In some embodiments, a diaphragm is provided between the first electrode and the second electrode;

[0026] In the first direction, in the positive electrode, the insulating layer extends beyond the diaphragm towards the tab, or the end of the insulating layer near the tab is flush with the diaphragm.

[0027] By ensuring that the end of the insulating layer extends beyond or is flush with the end of the diaphragm along the first direction on the side where the tab of the first electrode is located, the thickness of the tab layer of the first electrode is minimized after the first tab is bent and before the compression process. This reduces the degree of compression of the first tab in the first direction during the compression process, thereby helping to reduce the degree to which the first tab bends towards the main body along the bending point during compression. This helps to mitigate the problem of the first tab overlapping the second electrode due to movement towards the main body. Therefore, it helps to improve the problem of the electrode assembly becoming shorter due to the bending and compression processes of the first tab.

[0028] In some embodiments, on the side where the tab of the second electrode is located, the end of the film layer of the second electrode extends beyond the end of the first electrode, and the distance between the end of the film layer of the second electrode and the end of the first electrode is H2, where H2 ≥ 0.3 mm.

[0029] This configuration ensures a significant distance between the end of the film layer of the second electrode and the end of the first electrode on the side where the tab of the second electrode is located. Thus, after compression, even as the tab of the second electrode moves towards the first electrode along the bending point, a safe distance remains between them, mitigating the problem of short circuits within the electrode assembly caused by overlap between the tab and the first electrode.

[0030] In some embodiments, H2 ≥ 0.5 mm.

[0031] This design helps to improve the problem of the second electrode tab bending along the bend and overlapping with the first electrode, which causes internal shorting of the electrode assembly, thereby helping to improve the reliability of the cylindrical battery cell.

[0032] In some embodiments, the second electrode is a negative electrode, and in the negative electrode, the film layer includes a second active material layer disposed on the current collector.

[0033] This configuration results in a larger distance between the tab of the negative electrode and the positive electrode in the first direction. This helps to improve the problem of overlap between the tab of the negative electrode and the positive electrode when the tab of the negative electrode is inserted into the main body along the bend.

[0034] In some embodiments, the first electrode is a positive electrode and the second electrode is a negative electrode. In the positive electrode, the film layer includes a first active material layer and an insulating layer. Both the first active material layer and the insulating layer are disposed on the current collector. In the first direction, at least a portion of the insulating layer is disposed between the tab and the first active material layer.

[0035] Among them, the tensile strength of the combined structure of the film layer of the second electrode and the current collector of the second electrode is greater than the tensile strength of the tab of the second electrode, and is also greater than the tensile strength of the combined structure of the insulating layer and the current collector of the first electrode.

[0036] This design gives the combined structure of the second electrode film and the current collector of the second electrode, i.e., the combined structure of the second film and the current collector, greater tensile strength. On the one hand, after the second tab is bent, the combined structure of the second film and the current collector has greater compressive strength and is less prone to bending during the compression process. Therefore, after compression, a large safety distance can still be maintained between the second tab and the first electrode, effectively improving the problem of the second tab bending towards the main body and overlapping the first electrode during compression. This effectively addresses the issue of the electrode assembly being too short due to the bent tab design. On the other hand, it also mitigates the problem of the second film peeling off due to bending of the second electrode, contributing to improved reliability of the cylindrical battery cell.

[0037] In some embodiments, the second electrode is a negative electrode, in which the tensile strength of the combined structure of the film layer and the current collector is greater than the tensile strength of the tab, and is greater than or equal to 900 MPa.

[0038] By adopting the above technical solution, the combined structure of the second electrode film layer and the second electrode current collector, i.e., the combined structure of the second film layer and the second current collector, has greater tensile strength. This helps to improve the problem of internal shortness in the electrode assembly due to the bending of the tabs, and also helps to improve the problem of film layer detachment caused by electrode bending.

[0039] In some embodiments, the tensile strength of the electrode tab is less than or equal to 400 MPa.

[0040] This design results in lower tensile strength for the tabs, meaning they are more flexible. This prevents the tabs from forming large bends at the bending point during bending or compression, and also makes it less likely for these bends to extend axially along the cylindrical battery cell. Consequently, the bends are less likely to be inserted into the main body, thus reducing the risk of short circuits within the electrode assembly.

[0041] In some embodiments, in the first direction, the distance between the end of the membrane layer near the tab and the end of the tab away from the membrane layer is greater than or equal to 0.5 mm.

[0042] After the tab is compressed, there is a large distance between the end of the film layer near the tab and the end of the tab away from the film layer in the first direction, that is, the tab has a large tab layer thickness, which can effectively improve the problem of the tab being inserted into the main body along the bending position.

[0043] In some embodiments, the distance between the same end of any two membrane layers near the tab along the first direction is less than 1.2 mm.

[0044] This configuration ensures that the distance between any two film layers near the same end of the tab is small in the first direction. This improves the problem of tab insertion and overlap of electrodes with different polarities caused by a large distance between the same end of any two film layers near the tab.

[0045] In some embodiments, the electrode assembly has a winding axis parallel to a first direction, wherein, in the first direction, the end of the electrode tab away from the current collector body is provided with a bent section.

[0046] The bending section includes a first bending portion that bends relative to the current collector body in a direction close to the winding axis, and / or the bending section includes a second bending portion that bends relative to the current collector body in a direction away from the winding axis.

[0047] This design allows the end region of the electrode tab away from the current collector along the first direction to be bent, thus forming a relatively dense stacked layer. This facilitates electrode tab welding and provides strong binding force to the electrode sheet, resulting in higher charge / discharge performance of the electrode assembly.

[0048] In some embodiments, the bending segment includes at least one first bending portion and at least one second bending portion, wherein the first bending portion and the second bending portion are alternately arranged along a first direction.

[0049] This configuration allows the end region of the electrode tab that is away from the current collector body along the first direction to be bent, thereby forming a relatively dense accumulation layer.

[0050] In some embodiments, the first bending portion is bent radially along the electrode assembly, and / or the second bending portion is bent radially along the electrode assembly.

[0051] By adopting the above technical solution, the bending section is set to bend radially, which enables the tab to bend better.

[0052] Secondly, embodiments of this application provide a method for processing a cylindrical battery cell, applicable to cylindrical battery cells. The method for processing a cylindrical battery cell includes:

[0053] The tabs of the first electrode and the second electrode are respectively disposed at both ends of the electrode assembly along the first direction. On the side where the tab of the first electrode is located, the film layer of the first electrode extends beyond the second electrode along the first direction, and the distance between the end of the film layer of the first electrode and the end of the second electrode is ≥0.3mm.

[0054] The first and second electrodes are stacked and wound together.

[0055] Bend the electrode tabs;

[0056] In the first direction, the tab is compressed toward the current collector of the first electrode and the current collector of the second electrode.

[0057] The method for processing a cylindrical battery cell provided in this application embodiment involves, before stacking and winding the first and second electrodes, extending the film layer of the first electrode beyond the end of the second electrode in a first direction on the side where the tab of the first electrode is located, and ensuring that the distance between the end of the film layer of the first electrode and the end of the second electrode is ≥0.3mm. This results in a larger distance between the end of the film layer of the first electrode near the tab of the first electrode and the second electrode in the first direction. Thus, after the tab is compressed in step S40, even after the tab of the first electrode moves towards the second electrode along the bending position, a certain safe distance remains between the tab of the first electrode and the second electrode, thereby improving the problem of short circuits in the electrode assembly caused by overlap between the tab of the first electrode and the second electrode.

[0058] In some embodiments, before stacking and winding the first electrode and the second electrode, the method further includes:

[0059] On the side where the tab of the second electrode is located, the film layer of the second electrode extends beyond the end of the first electrode in a first direction, and the distance between the end of the film layer of the second electrode and the end of the first electrode is ≥0.3mm.

[0060] Thus, on the side where the tab of the second electrode is located, there is a large distance between the end of the film layer of the second electrode and the end of the first electrode. After the tab is compressed in step S40, after the tab of the second electrode moves towards the first electrode along the bending position, there is still a certain safe distance between the tab of the second electrode and the first electrode, which can improve the problem of short circuit in the electrode assembly caused by the tab of the second electrode overlapping with the first electrode.

[0061] In some embodiments, on the side where the tab of the first electrode is located, extending the film layer of the first electrode beyond the end of the second electrode along a first direction includes:

[0062] On the side where the tab of the first electrode is located, the insulating layer of the first electrode extends beyond the end of the second electrode in a first direction.

[0063] This configuration makes the first electrode a positive electrode, which can improve the problem of inserting the tab to connect with the negative electrode after the tab of the positive electrode has been bent and compressed.

[0064] In some embodiments, the first electrode and the second electrode are stacked and wound together, including:

[0065] The first electrode, the second electrode, and the diaphragm are stacked and wound together;

[0066] The tab bending setting includes:

[0067] The tab of the first electrode is bent so that the size of the tab in the first electrode in the first direction is ∈ [0.5mm, 3mm].

[0068] The tab of the second electrode is bent so that, in the first direction, the distance between the end of the tab away from the current collector and the diaphragm is ∈ [0.5mm, 3mm].

[0069] By adopting the above technical solution, the electrode layer thickness of the electrode is smaller after bending. This reduces the degree of compression of the electrode in the first direction during the compression process, which helps the electrode to form a bent structure along the bending position during the compression process. The problem of the bent structure being inserted into the main body is also improved, which helps to improve the problem of short electrode assembly.

[0070] In some embodiments, compressing the tab in a first direction toward the current collector of the first electrode and the current collector of the second electrode includes:

[0071] In the first direction, the tab of the first electrode is compressed toward the current collector body, and the tab of the second electrode is compressed toward the current collector body, so that the size difference of the electrode assembly before and after compression is less than 4mm.

[0072] This design ensures that the dimensional difference of the electrode assembly before and after compression is less than 4mm after the tab is compressed, resulting in a smaller degree of compression of the tab in the first direction. This helps to improve the problem of the bent structure formed on the tab due to compression being inserted into the main body, thereby effectively improving the problem of the electrode assembly being short due to the bending of the tab.

[0073] Thirdly, embodiments of this application provide a battery device, including a cylindrical battery cell.

[0074] The battery device provided in this application, by employing the cylindrical battery cell described above, ensures that after the tab compression process, even after the tab of the first electrode moves towards the second electrode along the bending position, a certain safe distance remains between the tab of the first electrode and the second electrode. This improves the problem of short circuits in the electrode assembly caused by the tab of the first electrode overlapping with the second electrode. Thus, the reliability of the cylindrical battery cell is improved, thereby enhancing the reliability of the battery device.

[0075] Fourthly, embodiments of this application provide an electrical device, including a cylindrical battery cell or a battery device.

[0076] The electrical device provided in this application, by employing the cylindrical battery cells or battery devices described above, helps to improve the reliability of the cylindrical battery cells, thereby improving the reliability of the electrical device.

[0077] The above description is only an overview of the technical solution of this application. In order to better understand the technical means of this application and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of this application more obvious and understandable, the following are specific embodiments of this application. Attached Figure Description

[0078] To more clearly illustrate the technical solutions in the embodiments of this application, the drawings used in the description of the embodiments or exemplary technologies will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0079] Figure 1 is a schematic diagram of a vehicle provided in some embodiments of this application;

[0080] Figure 2 is an exploded view of a battery device provided in some embodiments of this application;

[0081] Figure 3 is a three-dimensional structural diagram of a cylindrical battery cell provided in some embodiments of this application;

[0082] Figure 4 is a cross-sectional view of Figure 3 along AA;

[0083] Figure 5 is a schematic diagram of the electrode assembly of the cylindrical battery cell shown in Figure 4;

[0084] Figure 6 is an enlarged view of point B in Figure 5;

[0085] Figure 7 is an enlarged view of point C in Figure 5;

[0086] Figure 8 is a cross-sectional view of the electrode assembly of a cylindrical battery cell provided in some other embodiments of this application;

[0087] Figure 9 is an enlarged view of point D in Figure 8;

[0088] Figure 10 is a schematic diagram of the electrode assembly shown in Figure 5 before compression;

[0089] Figure 11 is an enlarged view of point E in Figure 10;

[0090] Figure 12 is an enlarged view of point F in Figure 10;

[0091] Figure 13 is a flowchart of a method for processing a battery cell according to some embodiments of this application.

[0092] The following are the labeling elements in the figure:

[0093] 1000 - Vehicle; 100 - Battery device; 200 - Controller; 300 - Motor; 10 - Cylindrical battery cell; 1 - Electrode assembly; 101 - Center hole; 11 - Electrode; 11a - First electrode; 11b - Second electrode; 111 - Current collector; 111a - First current collector; 111b - Second current collector; 1111 - Current collector body; 1111a - First current collector body; 1111b - Second current collector body; 1112 - Tab; 1112a - First tab; 1112b - Second tab; 11121 - Bending section; 111211- First bending section; 111212- Second bending section; 11122- Straight section; 112- Membrane layer; 112a- First membrane layer; 112b- Second membrane layer; 1121- First active material layer; 1122- Insulating layer; 1123- Second active material layer; 12- Separator; 2- Outer shell; 21- Shell; 22- End cap; 20- Box body; 210- First part; 220- Second part; L- Winding axis; P- Bending structure; Q- Stacked layer; Z- First direction; Y- Radial. Detailed Implementation

[0094] The embodiments of this application are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this application, and should not be construed as limiting this application.

[0095] Unless otherwise specified, all embodiments and optional embodiments of this application can be combined to form new technical solutions.

[0096] Unless otherwise specified, all technical features and optional technical features of the embodiments of this application can be combined with each other to form new technical solutions.

[0097] In the description of the embodiments of this application, it should be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings. 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.

[0098] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined with "first" or "second" may explicitly or implicitly include one or more of that feature.

[0099] In the description of the embodiments of this application, "multiple" means two or more, and unless otherwise explicitly specified, "two or more" includes two. Correspondingly, "multiple groups" means two or more groups, including two groups.

[0100] In the description of the embodiments of this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. For those skilled in the art, the specific meaning of the above terms in this application can be understood according to the specific circumstances.

[0101] In the description of this application, 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 represent three possibilities: A exists, A and B exist simultaneously, and B exists. Additionally, in this application, the character " / " generally indicates that the preceding and following related objects have an "or" relationship.

[0102] Although this application has been described with reference to preferred embodiments, various modifications can be made thereto and components can be replaced with equivalents without departing from the scope of this application. In particular, the technical features mentioned in the various embodiments can be combined in any manner, provided there is no structural conflict. This application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

[0103] From a market perspective, the application of battery devices is becoming increasingly widespread. Battery devices are not only used in energy storage systems such as hydropower, thermal power, wind power, and solar power plants, but also extensively in electric vehicles such as electric bicycles, electric motorcycles, and electric cars, as well as in military equipment and aerospace. As the application areas of battery devices continue to expand, the market demand is also constantly increasing.

[0104] In related technologies, battery devices typically include one or more battery cells. A battery cell is the smallest unit used to store and output electrical energy. Battery cells can be cylindrical, flat, cuboid, or other shapes; a battery cell that is roughly cylindrical is called a cylindrical battery cell.

[0105] A cylindrical battery cell may include a cylindrical outer casing and an electrode assembly disposed within the casing. The electrode assembly mainly consists of two electrodes with opposite polarities, namely a positive electrode and a negative electrode. The positive and negative electrodes are alternately stacked and wound to roughly form a cylinder. The electrodes generally include tabs, which are full tabs. During the processing of the battery cell, the electrodes are first wound to form the electrode assembly. Then, the tabs are bent to gather and aggregate the ends of the tabs away from the electrode body, forming a relatively dense stacked layer. Then, the two ends of the electrode assembly are compressed to compress the stacked layer formed by the tabs. Finally, the compressed electrode assembly is assembled into the outer casing.

[0106] During the bending process, numerous bending points are formed on the tabs. During compression, the tabs are subjected to pressure moving towards the main body of the electrode assembly, causing them to move along the bending points towards the main body, forming a relatively vertical bending structure extending roughly along the axial direction of the cylindrical battery cell near these points. This bending structure of the tabs can easily insert into the main body, posing a significant risk of short circuits between the positive and negative electrodes, thus affecting the reliability of the cylindrical battery cell.

[0107] Based on the above considerations, embodiments of this application provide a cylindrical battery cell, its processing method, battery device, and power consumption device. By extending the film layer of the first electrode beyond the second electrode in a first direction towards the tab of the first electrode, and by ensuring that the distance between the end of the film layer of the first electrode near the tab and the second electrode is ≥0.3mm in the first direction, a significant distance is maintained between the end of the film layer of the first electrode near the tab and the second electrode. Thus, after compression, even after the tab of the first electrode moves towards the second electrode along the bending position, a certain safe distance remains between the tab and the second electrode, thereby mitigating the problem of short circuit between the tab and the second electrode and improving the reliability of the cylindrical battery cell.

[0108] The cylindrical battery cell involved in this application refers to the smallest unit used for storing and outputting electrical energy. The cylindrical battery cell can be a secondary battery or a primary battery. A secondary battery refers to a cylindrical battery cell that can be recharged after discharge to activate the active materials and continue to be used. The cylindrical battery cell can be a lithium-ion battery, sodium-ion battery, sodium-lithium-ion battery, lithium metal battery, sodium metal battery, lithium-sulfur battery, magnesium-ion battery, nickel-metal hydride battery, nickel-cadmium battery, lead-acid battery, etc.

[0109] The battery device involved in this application embodiment can be a single physical module comprising one or more cylindrical battery cells, used to provide voltage and capacity. When there are multiple cylindrical battery cells, the multiple cylindrical battery cells are connected in series, in parallel, or in a mixed connection via a busbar. A mixed connection refers to multiple cylindrical battery cells being connected in both series and parallel connections.

[0110] In some embodiments, the battery device can be a battery module. When there are multiple cylindrical battery cells, the multiple cylindrical battery cells are arranged and fixed to form a battery module. As an example, multiple cylindrical battery cells can be fixed to form a battery module using cable ties or the like. As an example, multiple cylindrical battery cells can be fixed to form a battery module using end plates, side plates, or the like.

[0111] In some embodiments, the battery device can be a battery pack, which may include a housing and cylindrical battery cells. As an example, the cylindrical battery cells may be directly housed within the housing. As another example, multiple cylindrical battery cells may first be formed into one or more battery modules and then housed within the housing.

[0112] The cylindrical battery cells and battery devices involved in the embodiments of this application can be used in energy storage devices that use cylindrical battery cells or battery devices as energy storage elements.

[0113] The energy storage device involved in this application embodiment can be an energy storage container or an energy storage cabinet. The energy storage device can be used in energy storage power stations, wind power generation systems, solar power generation systems, mobile power systems, or temporary power supply systems, etc. The energy storage device can store electrical energy as needed and output electrical energy when appropriate. For example, the energy storage device can store electrical energy during off-peak hours and provide power to relevant users or electrical devices during peak hours. The energy storage device can include one or more battery clusters, and each battery cluster includes multiple battery devices. Multiple battery devices in a battery cluster can be connected in series through a busbar to increase the voltage of the energy storage device. When the energy storage device includes multiple battery clusters, the multiple battery clusters can be connected in parallel to increase the capacity of the energy storage device.

[0114] The cylindrical battery cell and battery device provided in this application embodiment can also be used in electrical devices that use cylindrical battery cells or battery devices as power sources.

[0115] Electrical devices can include, but are not limited to, mobile phones, tablets, laptops, electric toys, power tools, electric vehicles, vehicles, ships, spacecraft, etc. Electric toys can include stationary or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys. Spacecraft can include airplanes, rockets, space shuttles, and spacecraft. Based on the power source, vehicles can be gasoline-powered vehicles, natural gas-powered vehicles, or new energy vehicles. New energy vehicles can be pure electric vehicles, hybrid electric vehicles, or range-extended electric vehicles. Based on the drive method, vehicles can be front-wheel drive vehicles, rear-wheel drive vehicles, or four-wheel drive vehicles.

[0116] For ease of description, this application uses a vehicle as an example to illustrate the embodiments of the electrical device.

[0117] In some embodiments, please refer to FIG1, which is a schematic diagram of a vehicle 1000 provided in some embodiments of this application. A battery device 100 is disposed inside the vehicle 1000, and the battery device 100 may be located at the bottom, front, or rear of the vehicle 1000. The battery device 100 can be used to power the vehicle 1000; for example, the battery device 100 can serve as the operating power source for the vehicle 1000. The vehicle 1000 may also include a controller 200 and a motor 300. The controller 200 is used to control the battery device 100 to supply power to the motor 300, for example, to meet the power requirements of the vehicle 1000 during startup, navigation, and driving.

[0118] In some embodiments, the battery device 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.

[0119] In some embodiments, please refer to FIG2, which is an exploded view of a battery device 100 provided in some embodiments of this application. The battery device 100 may include a housing 20 and cylindrical battery cells 10. The housing 20 is a structure with an internal space for accommodating the cylindrical battery cells 10.

[0120] The housing 20 can adopt various structures. In some embodiments, the housing 20 may include a first portion 210 and a second portion 220, which overlap each other and together define the internal space of the housing 20, which is a closed space. Here, "closed" means covered or closed, and can be sealed or unsealed. That is, the housing 20 can be a sealed structure or an unsealed structure.

[0121] In this configuration, both the first part 210 and the second part 220 can be hollow structures with an opening at one end. The open side of the first part 210 covers the open side of the second part 220, so that the first part 210 and the second part 220 together define the internal space of the box 20. Alternatively, referring to Figure 2, the first part 210 can be a hollow structure with an opening at one end, and the second part 220 is a plate-like structure. The second part 220 covers the open side of the first part 210, so that the first part 210 and the second part 220 together define the internal space of the box 20.

[0122] The box 20, which is composed of the first part 210 and the second part 220, can be of various shapes, such as cylinder, cuboid, etc.

[0123] In some embodiments, multiple cylindrical battery cells 10 can be connected in series, parallel, or mixed to form a whole, and then the whole formed by the multiple cylindrical battery cells 10 is directly housed in the internal space of the housing 20. In other embodiments, multiple cylindrical battery cells 10 can also be connected in series, parallel, or mixed to form a battery module, and the battery module is housed in the internal space of the housing 20. In still other embodiments, multiple cylindrical battery cells 10 can also be connected in series, parallel, or mixed to form multiple battery modules, and the multiple battery modules can then be connected in series, parallel, or mixed to form a whole, and housed in the internal space of the housing 20.

[0124] In some embodiments, referring to Figures 1 and 2, the housing 20 of the battery device 100 can be part of the chassis structure of the vehicle 1000. For example, a portion of the housing 20 can be at least a portion of the floor of the vehicle 1000, or a portion of the housing 20 can be at least a portion of the crossbeams and longitudinal beams of the vehicle 1000.

[0125] In some embodiments, please refer to Figures 3 to 5 together with other accompanying drawings. Figure 3 is a perspective structural diagram of a cylindrical battery cell 10 provided in some embodiments of this application; Figure 4 is a cross-sectional view along line AA in Figure 3; and Figure 5 is a schematic diagram of the electrode assembly 1 of the cylindrical battery cell 10 provided in Figure 4. The cylindrical battery cell 10 provided in the embodiments of this application may include the electrode assembly 1 and the housing 2.

[0126] Electrode assembly 1 is the component in the cylindrical battery cell 10 where the electrochemical reaction takes place. Electrode assembly 1 is mainly formed by alternating layers and winding of positive and negative electrode plates, with a separator 12 between the positive and negative electrode plates. The separator 12 isolates the positive and negative electrode plates, thus insulating them.

[0127] In the cylindrical battery cell 10, the number of electrode components 1 can be one or more.

[0128] Among them, electrode assembly 1 can also be referred to as bare cell, winding body, etc.

[0129] In some embodiments, the cylindrical battery cell 10 may further include an electrolyte, which acts as a conductor of ions between the positive and negative electrode plates. The electrolyte described in this application embodiment may be liquid, gel-like, or solid.

[0130] The housing 2 is used to define the internal environment of the cylindrical battery cell 10 and to house the electrode assembly 1 and the electrolyte.

[0131] In some embodiments, please refer to Figures 3 to 5 together with other figures. The housing 2 may include a housing 21 and an end cap 22, which are components for jointly defining the internal environment of the cylindrical battery cell 10. The internal environment defined by the housing 21 and the end cap 22 is used to accommodate the electrode assembly 1 and the electrolyte.

[0132] The outer shell 2 is cylindrical. Specifically, the shell 21 is cylindrical.

[0133] As shown in Figures 3 and 4, the housing 21 and the end cap 22 can be independent components. Specifically, the housing 21 has an opening, and the end cap 22 is placed over the opening of the housing 21 to jointly define the internal environment of the cylindrical battery cell 10 and isolate the internal environment of the cylindrical battery cell 10 from the external environment. Alternatively, the housing 21 and the end cap 22 can be an integrated structure. Specifically, the end cap 22 and the housing 21 can form a common connection surface before the electrode assembly 1 is inserted into the housing. After the electrode assembly 1 is inserted into the housing, when it is necessary to encapsulate the electrode assembly 1, the end cap 22 closes the housing 21.

[0134] The outer casing 2 can be either a sealed or unsealed structure. As an example, if the outer casing 2 is a sealed structure, it can protect the electrode assembly 1 and, to some extent, prevent leakage such as electrolyte leakage. As another example, if the outer casing 2 is an unsealed structure, it can still protect the electrode assembly 1, and a sealing bag may be included between the outer casing 2 and the electrode assembly 1 to encapsulate the electrode assembly 1 and the electrolyte. Specifically, the sealing bag can be a bag-shaped insulating structure, Mylar membrane, etc.

[0135] As shown in Figures 3 and 4, there can be one end cap 22, which is located at one end of the housing 21. Alternatively, there can be two end caps 22, which are located at opposite ends of the housing 21.

[0136] The shell 21 and end cap 22 can be made of various materials, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc.

[0137] Please refer to Figures 3 through 7, and in conjunction with other accompanying drawings. Figure 6 is an enlarged view of point B in Figure 5, and Figure 7 is an enlarged view of point C in Figure 5. The cylindrical battery cell 10 provided in this embodiment includes an electrode assembly 1 and a housing 2. At least a portion of the electrode assembly 1 is disposed within the housing 2. The electrode assembly 1 has a wound structure and includes a first electrode 11a and a second electrode 11b, the first electrode 11a and the second electrode 11b having opposite polarities. Both the first electrode 11a and the second electrode 11b include a current collector 111 and a film layer 112 disposed on the current collector 111. The current collector 111 includes a current collector body 1111 arranged along the first direction Z and an electrode tab 1112. The film layer 112 is disposed on the current collector body 1111. The portion of the current collector 111 extending beyond the film layer 112 along the first direction Z is the electrode tab 1112. The electrode tab 1112 is bent. The electrode tabs 1112 of the first electrode 11a and the second electrode 11b are respectively disposed at both ends of the electrode assembly 1 along the first direction Z. On the side where the electrode tab 1112 of the first electrode 11a is located, the end of the film layer 112 of the first electrode 11a extends beyond the end of the second electrode 11b along the first direction Z. The distance between the end of the film layer 112 of the first electrode 11a and the end of the second electrode 11b is H1, where H1 ≥ 0.3 mm.

[0138] Understandably, the electrode assembly 1 includes two electrodes 11, which are a first electrode 11a and a second electrode 11b, respectively. The first electrode 11a is the positive electrode and the second electrode 11b is the negative electrode; or, the first electrode 11a is the negative electrode and the second electrode 11b is the positive electrode.

[0139] The electrode assembly 1 has a wound structure, meaning that the electrode sheets 11 are wound together to form a wound structure. Specifically, both the first electrode sheet 11a and the second electrode sheet 11b are wound together to form a wound structure, so that the electrode assembly 1 can be approximately cylindrical. Correspondingly, the outer casing 2 is approximately cylindrical, making the cylindrical battery cell 10 cylindrical in shape.

[0140] The cylindrical battery cell 10 has a winding axis L, which extends along a first direction Z. Furthermore, a first electrode 11a and a second electrode 11b are wound around the winding axis L to form a wound structure.

[0141] The current collector 111 refers to a component with conductive properties used for current collection. The current collector 111 is divided into two parts along the first direction Z: the current collection body 1111 and the electrode tab 1112. The current collector 111 may be, but is not limited to, a metallic structure.

[0142] Membrane layer 112 refers to the structural layer disposed on the current collection body 1111. Membrane layer 112 may include an active material layer, which is a structural layer composed of active materials.

[0143] In the current collector 111, the part with the membrane layer 112 is the current collector body 1111, and the part without the membrane layer 112 is the tab 1112.

[0144] The current collector 1111 of the first electrode 11a, the film layer 112 of the first electrode 11a, the current collector 1111 of the second electrode 11b, and the film layer 112 of the second electrode 11b constitute the main body of the electrode assembly 1. The tabs 1112 of the first electrode 11a and the tabs 1112 of the second electrode 11b are respectively disposed at both ends of the electrode assembly 1 along the first direction Z, meaning that the tabs 1112 of the first electrode 11a and the tabs 1112 of the second electrode 11b are respectively disposed at both ends of the main body along the first direction Z.

[0145] For ease of description, the current collector 111 of the first electrode 11a is defined as the first current collector 111a, and the current collector 111 of the second electrode 11b is defined as the second current collector 111b. The current collector body 1111 of the first electrode 11a is defined as the first current collector body 1111a, and the current collector body 1111 of the second electrode 11b is defined as the second current collector body 1111b. The tab 1112 of the first electrode 11a is defined as the first tab 1112a, and the tab 1112 of the second electrode 11b is defined as the second tab 1112b. The film layer 112 of the first electrode 11a is defined as the first film layer 112a, and the film layer 112 of the second electrode 11b is defined as the second film layer 112b. The active material layer of the first electrode 11a is defined as the first active material layer 1121, and the active material layer of the second electrode 11b is defined as the second active material layer.

[0146] Understandably, the first electrode 11a includes a first current collector 111a and a first film layer 112a. The first current collector 111a includes a first current collector body 1111a and a first tab 1112a arranged along the first direction Z. The first film layer 112a is disposed on the first current collector body 1111a and includes a first active material layer 1121. In the first current collector 111a, the portion where the first film layer 112a is disposed is the first current collector body 1111a, and the portion of the first current collector 111a extending beyond the first film layer 112a along the first direction Z is the first tab 1112a. The second electrode 11b includes a second current collector 111b and a second film layer 112b. The second current collector 111b includes a second current collector body 1111b and a second tab 1112b arranged along the first direction Z. The second film layer 112b is disposed on the second current collector body 1111b and includes a second active material layer 1123. In the second current collector 111b, the portion where the second film layer 112b is disposed is the second current collector body 1111b, and the portion of the second current collector 111b extending beyond the second film layer 112b along the first direction Z is the second tab 1112b. Both the first tab 1112a and the second tab 1112b are bent. The first current collector body 1111a, the first film layer 112a, the second current collector body 1111b, and the second film layer 112b constitute the main body of the electrode assembly 1. The first tab 1112a and the second tab 1112b are respectively disposed at both ends of the main body along the first direction Z.

[0147] On the side where the tab 1112 of the first electrode 11a is located, the film layer 112 of the first electrode 11a extends beyond the end of the second electrode 11b. Specifically, in the first direction Z, the first film layer 112a extends beyond the second electrode 11b in a direction close to the first tab 1112a.

[0148] On the side where the tab 1112 of the first electrode 11a is located, the distance between the end of the film layer 112 of the first electrode 11a and the end of the second electrode 11b can be any distance in any direction on the side where the tab 1112 of the first electrode 11a is located. As an example, as shown in FIG6, on the side where the tab 1112 of the first electrode 11a is located, the distance between the end of the film layer 112 of the first electrode 11a and the end of the second electrode 11b in the first direction Z is H1.

[0149] On the side where the tab 1112 of the first electrode 11a is located, the distance between the end of the film layer 112 of the first electrode 11a and the end of the second electrode 11b is specifically H1 in the first direction Z, where the end of the first film layer 112a near the first tab 1112a is H1 and the end of the second current collector 1111b away from the second tab 1112b.

[0150] Where H1 can be 0.3mm, 0.31mm, 0.32mm, 0.33mm, 0.34mm, 0.35mm, 0.36mm, 0.37mm, 0.38mm, 0.39mm, 0.4mm, 0.41mm, 0.42mm, 0.43mm, 0.44mm, 0.45mm, 0.46mm, 0.47mm, 0.48mm, or 0.49mm. 0.5mm, 0.51mm, 0.52mm, 0.53mm, 0.54mm, 0.55mm, 0.56mm, 0.57mm, 0.58mm, 0.59mm, 0.6mm, 0.61mm, 0.62mm, 0.63mm, 0.64mm, 0.65mm, 0.66mm, 0.67mm, 0.68mm, 0.69mm, 0.7mm, etc.

[0151] Wherein, H1 is the distance between the first electrode 11a and the second electrode 11b when they are in the unfolded state.

[0152] Wherein, the first direction Z is the axial direction of the cylindrical battery cell 10, and the first direction Z is parallel to the winding axis L.

[0153] The cylindrical battery cell 10 provided in this application embodiment has a larger distance between the end of the film layer 112 of the first electrode 11a and the end of the second electrode 11b on the side where the tab 1112 of the first electrode 11a is located. This is achieved by ensuring that the distance between the end of the film layer 112 of the first electrode 11a and the end of the second electrode 11b is ≥0.3mm. Thus, after the tab 1112 is compressed, even after the tab 1112 of the first electrode 11a moves towards the second electrode 11b along the bending position, a certain safe distance still exists between the tab 1112 of the first electrode 11a and the second electrode 11b. This improves the problem of short internal distance in the electrode assembly 1 caused by the tab 1112 of the first electrode 11a overlapping with the second electrode 11b. Specifically, in the first direction Z, there is a large distance between the end of the first film layer 112a near the first tab 1112a and the second electrode 11b. After compression, even after the first tab 1112a moves towards the main body along the bending position, there is still a certain safe distance between the first tab 1112a and the second electrode 11b. This can improve the problem of short circuits in the electrode assembly 1 caused by the first tab 1112a and the second electrode 11b overlapping. Therefore, it helps to improve the reliability of the cylindrical battery cell 10.

[0154] In some cases, cutting the tab 1112 into multiple smaller tabs 1112 can reduce the risk of internal shorting caused by the tab 1112 being inserted into the main body along the bend. However, with this arrangement, the smaller tabs 1112 are prone to folding towards the main body, resulting in internal shorting. Furthermore, the space between the multiple smaller tabs 1112 can form a channel for metal particles to enter the main body, leading to a risk of self-discharge in the cylindrical battery cell 10. The cylindrical battery cell 10 provided in this application, by having a distance ≥0.3mm between the end of the first film layer 112a and the end of the second current collector 1111b on the side where the tab 1112 of the first electrode 11a is located, can improve the problem of shorting between the first tab 1112a and the second electrode 11b caused by the insertion of the first tab 1112a into the main body, thereby reducing the risk of internal shorting of the electrode assembly 1 and preventing the formation of a channel for metal particles to enter the main body.

[0155] In some embodiments, please refer to Figure 6, and in conjunction with other figures. H1 ≥ 0.5 mm.

[0156] Specifically, H1 can be 0.5mm, 0.51mm, 0.52mm, 0.53mm, 0.54mm, 0.55mm, 0.56mm, 0.57mm, 0.58mm, 0.59mm, 0.6mm, 0.61mm, 0.62mm, 0.63mm, 0.64mm, 0.65mm, 0.66mm, 0.67mm, 0.68mm, 0.69mm, 0.7mm, 0.71mm, 0.72mm, 0.73mm, 0.74mm, 0.75mm, 0.76mm, 0.77mm, 0.78mm, 0.79mm, 0.8mm, etc.

[0157] This configuration helps to improve the problem of the electrode assembly 1 experiencing internal shorting when the tab 1112 of the first electrode 11a bends along the bending position and overlaps with the second electrode 11b, thereby helping to improve the reliability of the cylindrical battery cell 10.

[0158] In some embodiments, please refer to Figures 4 to 6 together with other figures. The first electrode 11a is a positive electrode, and the second electrode 11b is a negative electrode. In the positive electrode, the film layer 112 includes a first active material layer 1121 and an insulating layer 1122, both of which are disposed on the current collector 1111. In the first direction Z, at least a portion of the insulating layer 1122 is disposed between the tab 1112 and the first active material layer 1121.

[0159] The first active material layer 1121 refers to a structural layer composed of active materials, and the insulating layer 1122 refers to a structural layer composed of materials with insulating properties.

[0160] The first active material layer 1121 and the insulating layer 1122 can be distributed along the first direction Z, so as to be respectively disposed on two parts of the current collecting body 1111 along the first direction Z. Alternatively, a part of the insulating layer 1122 and the first active material layer 1121 are distributed along the first direction Z, so as to be respectively disposed on two parts of the current collecting body 1111 along the first direction Z; the other part of the insulating layer 1122 is disposed on the first active material layer 1121.

[0161] Understandably, the first membrane layer 112a includes a first active material layer 1121 and a first insulating layer 1122, both of which are disposed on the first current collector 1111a. In the first direction Z, at least a portion of the insulating layer 1122 is disposed between the first tab 1112a and the first active material layer 1121.

[0162] On the side where the tab 1112 of the first electrode 11a is located, the film layer 112 of the first electrode 11a extends beyond the end of the second electrode 11b along the first direction Z. Specifically, in the first direction Z, the insulating layer 1122 extends beyond the second electrode 11b in a direction close to the first tab 1112a.

[0163] On the side where the tab 1112 of the first electrode 11a is located, the distance between the end of the film layer 112 of the first electrode 11a and the end of the second electrode 11b is specifically the distance in the first direction Z between the end of the insulating layer 1122 near the first tab 1112a and the end of the second current collector 1111b away from the second tab 1112b.

[0164] This configuration results in a larger distance between the tab 1112 of the positive electrode and the negative electrode in the first direction Z. This helps to improve the problem of overlap between the tab 1112 of the positive electrode and the negative electrode when the tab 1112 of the positive electrode is inserted into the main body along the bending position.

[0165] In some embodiments, the first electrode 11a can be a negative electrode, and the second electrode 11b can be a positive electrode. Based on this, the statement that the film layer 112 of the first electrode 11a extends beyond the end of the second electrode 11b along the first direction Z on the side where the tab 1112 of the first electrode 11a is located means that the active material layer of the negative electrode extends beyond the end of the positive electrode along the first direction Z on the side where the tab 1112 of the first electrode 11a is located. Specifically, the distance between the end of the film layer 112 of the first electrode 11a and the end of the second electrode 11b on the side where the tab 1112 of the first electrode 11a is located is H1, which is the distance along the first direction Z between the end of the film layer 112 of the negative electrode near the tab 1112 of the negative electrode and the end of the current collector 1111 of the positive electrode away from the tab 1112 of the positive electrode.

[0166] In some embodiments, in the positive electrode sheet, the tensile strength of the combined structure of the insulating layer 1122 and the current collector 1111 is greater than the tensile strength of the tab 1112.

[0167] Understandably, the tensile strength of the combined structure of the insulating layer 1122 and the first current collector 1111a is greater than the tensile strength of the first tab 1112a and greater than the tensile strength of the second tab 1112b.

[0168] This design allows the combined structure of the insulating layer 1122 and the current collector 1111 of the positive electrode to have high tensile strength. Thus, after the tab 1112 is bent, during the compression process, the combined structure of the insulating layer 1122 and the current collector 1111 of the positive electrode can withstand greater pressure and is less prone to bending. Therefore, after compression, a large safety distance can still be maintained between the tab 1112 of the positive electrode and the negative electrode, effectively improving the problem of the tab 1112 of the positive electrode bending towards the main body along the bending point during compression and overlapping the negative electrode. This effectively addresses the issue of the electrode assembly 1 being internally short due to the bending design of the tab 1112.

[0169] In some embodiments, in the positive electrode sheet, the tensile strength of the combined structure of the insulating layer 1122 and the current collector 1111 is greater than 1.5 times the tensile strength of the tab 1112.

[0170] Understandably, the tensile strength of the assembly structure of the insulating layer 1122 and the first current collector 1111a is greater than 1.5 times the tensile strength of the first tab 1112a.

[0171] In this way, the combined structure of the insulating layer 1122 and the current collector body 1111 of the positive electrode has a large tensile strength, so it has a large pressure resistance and is not easy to bend. Therefore, after the tab 1112 is compressed, a large safety distance can still be maintained between the tab 1112 of the positive electrode and the negative electrode. This can effectively improve the problem of the tab 1112 of the positive electrode bending towards the body along the bending position during the compression process and overlapping the negative electrode. This can effectively improve the problem of the electrode assembly 1 being short due to the bending setting of the tab 1112.

[0172] In some embodiments, in the positive electrode sheet, the tensile strength of the combined structure of the insulating layer 1122 and the current collector 1111 is greater than or equal to 600 MPa.

[0173] Specifically, the tensile strength of the combined structure of the insulating layer 1122 and the current collector 1111 of the positive electrode sheet can be 600 MPa, 610 MPa, 620 MPa, 630 MPa, 640 MPa, 650 MPa, 660 MPa, 670 MPa, 680 MPa, 690 MPa, 700 MPa, 710 MPa, 720 MPa, 730 MPa, 740 MPa, 750 MPa, 760 MPa, 770 MPa, 780 MPa, 790 MPa, 800 MPa, 810 MPa, 820 MPa, 830 MPa, 840 MPa, 850 MPa, 860 MPa, 870 MPa, 890 MPa, etc.

[0174] In this way, the combined structure of the insulating layer 1122 and the current collector body 1111 of the positive electrode has a large tensile strength, so it has a large pressure resistance and is not easy to bend. Therefore, after the tab 1112 is compressed, a large safety distance can still be maintained between the tab 1112 of the positive electrode and the negative electrode. This can effectively improve the problem of the tab 1112 of the positive electrode bending towards the body along the bending position during the compression process and overlapping the negative electrode. This can effectively improve the problem of the electrode assembly 1 being short due to the bending setting of the tab 1112.

[0175] In some embodiments, please refer to FIG6, and in conjunction with other figures. An insulating layer 1122 is disposed on both sides of the first current collector 1111a along the thickness direction of the first current collector 1111a. The thickness of the insulating layer 1122 on one side of the first current collector 1111a is ≥10 μm, which helps to give the insulating layer 1122 greater tensile strength.

[0176] In some embodiments, please refer to Figures 4 to 6 together, and in conjunction with other figures. A diaphragm 12 is provided between the first electrode 11a and the second electrode 11b.

[0177] Understandably, the first current collector 1111a, the first membrane layer 112a, the second current collector 1111b, the second membrane layer 112b, and the diaphragm 12 constitute the main body. The diaphragm 12 is disposed between the first electrode 11a and the second electrode 11b, thereby achieving insulation between the first electrode 11a and the second electrode 11b.

[0178] In some possible designs, please refer to Figures 4 through 6 together with other figures. In the first direction Z, in the positive electrode, the insulating layer 1122 extends beyond the separator 12 in a direction close to the tab 1112.

[0179] Specifically, in the first direction Z, the insulating layer 1122 extends beyond the diaphragm 12 in a direction close to the first tab 1112a.

[0180] In some other possible designs, in the first direction Z, in the positive electrode sheet, the end of the insulating layer 1122 near the tab 1112 is flush with the diaphragm 12.

[0181] Specifically, in the first direction Z, the end of the insulating layer 1122 near the first tab 1112a is flush with the end of the diaphragm 12 near the first tab 1112a.

[0182] By adopting the above technical solution, with a predetermined protective margin for the first tab 1112a after bending and before compression, and a predetermined tab layer thickness after compression, the end of the insulating layer 1122 extends beyond or is flush with the end of the diaphragm 12 along the first direction Z on the side where the tab 1112a is located. This minimizes the tab layer thickness of the first tab 1112a after bending and before compression. Thus, during compression, the degree of compression of the first tab 1112a in the first direction Z can be reduced, thereby helping to reduce the degree to which the first tab 1112a bends towards the main body along the bending position during compression. This helps to improve the problem of the first tab 1112a overlapping the second electrode 11b as it moves towards the main body. Therefore, it helps to improve the problem of the electrode assembly 1 being short due to the bending and compression of the first tab 1112a.

[0183] It should be further explained that after the bending treatment and before the compression treatment of the first tab 1112a, welding treatment is generally required for the first tab 1112a. Therefore, a protective margin needs to be set for the first tab 1112a so that the minimum distance between the end of the first tab 1112a away from the insulating layer 1122 and the diaphragm 12 or the insulating layer 1122 is within a certain range. This can improve the problem of sparks melting the diaphragm 12 or the membrane layer 112 during the welding process. Specifically, in the first direction Z, when the insulating layer 1122 extends beyond the diaphragm 12 in the direction closer to the first tab 1112a, the protective margin of the first tab 1112a refers to the distance between the end of the first tab 1112a away from the membrane layer 112 and the end of the insulating layer 1122 close to the first tab 1112a in the first direction Z after the bending treatment and before the compression treatment. In the first direction Z, when the diaphragm 12 extends beyond the end of the insulating layer 1122 near the first tab 1112a, the protection margin of the first tab 1112a refers to the distance between the end of the first tab 1112a away from the insulating layer 1122 and the end of the diaphragm 12 near the first tab 1112a in the first direction Z after the first tab 1112a is bent and before the first tab 1112a is compressed.

[0184] The electrode layer thickness of the first electrode tab 1112a refers to the distance between the end of the first electrode tab 1112a away from the insulating layer 1122 and the end of the insulating layer 1122 close to the first electrode tab 1112a in the first direction Z.

[0185] In some embodiments, please refer to Figures 5 to 7 together with other figures. In the first direction Z, the diaphragm 12 extends beyond the end of the first current collector 1111a and the first membrane layer 112a that is opposite to the first tab 1112a.

[0186] In some embodiments, please refer to Figures 4 to 7 together with other figures. On the side where the tab 1112 of the second electrode 11b is located, the film layer 112 of the second electrode 11b extends beyond the end of the first electrode 11a along the first direction Z, and the distance between the end of the film layer 112 of the second electrode 11b and the end of the first electrode 11a is H2, where H2 ≥ 0.3 mm.

[0187] On the side where the tab 1112 of the second electrode 11b is located, the film layer 112 of the second electrode 11b extends beyond the end of the first electrode 11a along the first direction Z. Specifically, in the first direction Z, the second film layer 112b extends beyond the first electrode 11a in a direction close to the second tab 1112b.

[0188] On the side where the tab 1112 of the second electrode 11b is located, the distance between the end of the film layer 112 of the second electrode 11b and the end of the first electrode 11a can be any distance in any direction on the side where the tab 1112 of the second electrode 11b is located. As an example, as shown in FIG7, on the side where the tab 1112 of the second electrode 11b is located, the distance between the end of the film layer 112 of the second electrode 11b and the end of the first electrode 11a in the first direction Z is H2.

[0189] On the side where the tab 1112 of the second electrode 11b is located, the distance between the end of the film layer 112 of the second electrode 11b and the end of the first electrode 11a is specifically the distance in the first direction Z between the end of the second film layer 112b near the second tab 1112b and the end of the first current collector 1111a away from the first tab 1112a.

[0190] Where H2 can be 0.3mm, 0.31mm, 0.32mm, 0.33mm, 0.34mm, 0.35mm, 0.36mm, 0.37mm, 0.38mm, 0.39mm, 0.4mm, 0.41mm, 0.42mm, 0.43mm, 0.44mm, 0.45mm, 0.46mm, 0.47mm, 0.48mm, or 0.49mm. 0.5mm, 0.51mm, 0.52mm, 0.53mm, 0.54mm, 0.55mm, 0.56mm, 0.57mm, 0.58mm, 0.59mm, 0.6mm, 0.61mm, 0.62mm, 0.63mm, 0.64mm, 0.65mm, 0.66mm, 0.67mm, 0.68mm, 0.69mm, 0.7mm, etc.

[0191] Wherein, H2 is the distance between the first electrode 11a and the second electrode 11b when they are in the unfolded state.

[0192] This configuration ensures a significant distance between the end of the film layer 112 of the second electrode 11b and the end of the first electrode 11a on the side where the tab 1112 of the second electrode 11b is located. Thus, after compression, even after the tab 1112 of the second electrode 11b moves towards the first electrode 11a along the bending position, a certain safe distance remains between the tab 1112 of the second electrode 11b and the first electrode 11a. This mitigates the problem of short circuits in the electrode assembly 1 caused by the tab 1112 of the second electrode 11b overlapping with the first electrode 11a. Specifically, on the side where the tab 1112 of the second electrode 11b is located, there is a large distance between the end of the second film layer 112b and the end of the first electrode 11a. After compression, even after the second tab 1112b moves towards the main body along the bending position, a certain safe distance still exists between the second tab 1112b and the first electrode 11a. This improves the problem of short circuits in the electrode assembly 1 caused by overlap between the second tab 1112b and the first electrode 11a. Therefore, it helps to improve the reliability of the cylindrical battery cell 10.

[0193] In some embodiments, please refer to Figure 7, and in conjunction with other figures. H2 ≥ 0.5 mm.

[0194] Specifically, H2 can be 0.5mm, 0.51mm, 0.52mm, 0.53mm, 0.54mm, 0.55mm, 0.56mm, 0.57mm, 0.58mm, 0.59mm, 0.6mm, 0.61mm, 0.62mm, 0.63mm, 0.64mm, 0.65mm, 0.66mm, 0.67mm, 0.68mm, 0.69mm, 0.7mm, 0.71mm, 0.72mm, 0.73mm, 0.74mm, 0.75mm, 0.76mm, 0.77mm, 0.78mm, 0.79mm, 0.8mm, etc.

[0195] This configuration helps to improve the problem of the electrode assembly 1 experiencing internal shorting when the tab 1112 of the second electrode 11b bends along the bending position and overlaps with the first electrode 11a, thereby helping to improve the reliability of the cylindrical battery cell 10.

[0196] In some embodiments, please refer to FIG7 and other accompanying drawings. The first electrode 11a is a positive electrode, and the second electrode 11b is a negative electrode. In the negative electrode, the film layer 112 includes a second active material layer 1123, which is disposed on the current collector 1111.

[0197] The second active substance layer 1123 refers to the structural layer composed of active substances.

[0198] Understandably, the second membrane layer 112b includes a second active material layer 1123, and both the second active material layer 1123 and the insulating layer 1122 are disposed on the second current collector 1111b.

[0199] On the side where the tab 1112 of the second electrode 11b is located, the film layer 112 of the second electrode 11b extends beyond the end of the first electrode 11a along the first direction Z. Specifically, in the first direction Z, the second active material layer 1123 extends beyond the first electrode 11a in a direction close to the second tab 1112b.

[0200] On the side where the tab 1112 of the second electrode 11b is located, the distance between the end of the film layer 112 of the second electrode 11b and the end of the first electrode 11a is specifically the distance in the first direction Z between the end of the second active material layer 1123 near the second tab 1112b and the end of the first current collector 1111a away from the first tab 1112a, which is H2.

[0201] This configuration results in a larger distance between the tab 1112 of the negative electrode and the positive electrode in the first direction Z. This helps to improve the problem of the tab 1112 of the negative electrode being inserted into the main body along the bending position, causing the tab 1112 of the negative electrode to overlap with the positive electrode.

[0202] In some embodiments, please refer to FIG7, and in conjunction with other figures. In the first direction Z, the diaphragm 12 extends beyond the second current collector 1111b and the second active material layer 1123 in a direction close to the second tab 1112b.

[0203] In some embodiments, please refer to FIG6, and in conjunction with other figures. In the first direction Z, the diaphragm 12 extends beyond the first active material layer 1121 in a direction close to the first tab 1112a.

[0204] In some embodiments, please refer to Figures 4 to 7 together with other figures. The first electrode 11a is a positive electrode, and the second electrode 11b is a negative electrode. In the positive electrode, the film layer 112 includes a first active material layer 1121 and an insulating layer 1122, both of which are disposed on the current collector 1111. In the positive electrode, at least a portion of the insulating layer 1122 is disposed between the tab 1112 and the first active material layer 1121 in the first direction Z. The tensile strength of the combined structure of the film layer 112 of the second electrode 11b and the current collector 1111 of the second electrode 11b is greater than the tensile strength of the tab 1112 of the second electrode 11b, and greater than the tensile strength of the combined structure of the insulating layer 1122 and the current collector 1111 of the first electrode 11a.

[0205] Specifically, the first film layer 112a includes a first active material layer 1121 and an insulating layer 1122, both of which are disposed on the first current collector 1111a. In the first direction Z, at least a portion of the insulating layer 1122 is disposed between the first tab 1112a and the first active material layer 1121. The tensile strength of the combined structure of the second film layer 112b and the second current collector 1111b is greater than the tensile strength of the second tab 1112b, and also greater than the tensile strength of the combined structure of the insulating layer 1122 and the first current collector 1111a.

[0206] This configuration allows the combined structure of the film layer 112b and the current collector 1111b of the second electrode 11b—that is, the combined structure of the second film layer 112b and the current collector 1111b—to have greater tensile strength. Thus, on the one hand, after the second tab 1112b is bent, during the compression process, the combined structure of the second film layer 112b and the current collector 1111b can have greater pressure resistance and is less prone to bending. Therefore, after the compression of the second tab 1112b, a large safety distance can still be maintained between the second tab 1112b and the first electrode 11a. This effectively improves the problem of the second tab 1112b bending towards the main body along the bending position during compression and overlapping the first electrode 11a, thereby effectively improving the problem of the electrode assembly 1 being internally short due to the bending configuration of the tab 1112b. On the other hand, it can improve the problem of the second film layer 112b falling off due to bending of the second electrode 11b, which helps to improve the reliability of the cylindrical battery cell 10.

[0207] In some embodiments, the first electrode 11a is a positive electrode and the second electrode 11b is a negative electrode. In the negative electrode, the tensile strength of the combined structure of the film layer 112 and the current collector 1111 is greater than the tensile strength of the tab 1112, and is greater than or equal to 900 MPa.

[0208] Specifically, the tensile strength of the combined structure of the second membrane layer 112b and the second current collector 1111b is greater than the tensile strength of the second tab 1112b, and is greater than 900 MPa.

[0209] The tensile strength of the combined structure of the second membrane layer 112b and the second current collector 1111b can be 900MPa, 910MPa, 920MPa, 930MPa, 940MPa, 950MPa, 960MPa, 970MPa, 980MPa, 990MPa, 1000MPa, etc.

[0210] By adopting the above technical solution, the combined structure of the film layer 112b and the current collector 1111b of the second electrode 11b, i.e., the combined structure of the second film layer 112b and the current collector 1111b, has greater tensile strength. This helps to improve the problem of the electrode assembly 1 being too short due to the bending of the tab 1112, and also helps to improve the problem of the film layer 112 detaching due to the bending of the electrode 11.

[0211] In some embodiments, the combined structure of the second membrane layer 112b and the second current collector 1111b has a dimension greater than 100 μm in its thickness direction, which makes the combined structure of the second membrane layer 112b and the second current collector 1111b have a large tensile strength.

[0212] In some embodiments, the tensile strength of the tab 1112 is less than or equal to 400 MPa.

[0213] The tensile strength of the first tab 1112a can be less than or equal to 400 MPa, and the tensile strength of the second tab 1112b can also be less than or equal to 400 MPa.

[0214] The tensile strength of the tab 1112 can be 100 MPa, 110 MPa, 120 MPa, 130 MPa, 140 MPa, 150 MPa, 160 MPa, 170 MPa, 180 MPa, 190 MPa, 200 MPa, 210 MPa, 220 MPa, 230 MPa, 240 MPa, 250 MPa, 260 MPa, 270 MPa, 280 MPa, 290 MPa, 300 MPa, 310 MPa, 320 MPa, 330 MPa, 340 MPa, 350 MPa, 360 MPa, 370 MPa, 380 MPa, 390 MPa, 400 MPa, etc.

[0215] This design results in the tab 1112 having relatively low tensile strength, meaning the tab 1112 is relatively flexible. Therefore, during bending or compression of the tab 1112, it is less likely to form a large bending structure P at the bending point, and the bending structure P formed at the bending point is less likely to extend along the axial direction of the cylindrical battery cell 10. This makes it less likely for the bending structure P to be inserted into the main body, thus helping to reduce the risk of short circuits within the electrode assembly 1.

[0216] In some embodiments, the thickness of the first tab 1112a can be 8 μm to 20 μm.

[0217] The thickness of the first electrode 1112a refers to the dimension of the first electrode 1112a along its own thickness direction.

[0218] Specifically, the thickness of the first tab 1112a can be 8μm, 9μm, 10μm, 11μm, 12μm, 13μm, 14μm, 15μm, 16μm, 17μm, 18μm, 19μm, 20μm, etc.

[0219] This configuration helps to ensure that the tensile strength of the first tab 1112a is less than or equal to 400 MPa, thereby making the first tab 1112a have a smaller tensile strength, making it less likely to form a bending structure P, or making it less likely that the bending structure P formed by the first tab 1112a will extend along the axial direction of the cylindrical battery cell.

[0220] In some embodiments, the thickness of the second tab 1112b can be ≤8μm.

[0221] The thickness of the second tab 1112b refers to the dimension of the second tab 1112b along its own thickness direction.

[0222] Specifically, the thickness of the second tab 1112b can be 1μm, 2μm, 3μm, 4μm, 5μm, 6μm, 7μm, 8μm, etc.

[0223] This configuration helps to ensure that the tensile strength of the second tab 1112b is less than or equal to 400 MPa, thereby making the second tab 1112b have a smaller tensile strength, making it less likely to form a bending structure P, or making it less likely that the bending structure P formed by the second tab 1112b will extend along the axial direction of the cylindrical battery cell.

[0224] In some embodiments, the first current collector 111a can be aluminum foil, that is, both the first current collector body 1111a and the first tab 1112a can be aluminum foil. The second current collector 111b can be copper foil, that is, both the second current collector body 1111b and the second tab 1112b can be copper foil.

[0225] In some embodiments, please refer to Figures 6 and 7 together, and in conjunction with other figures. In the first direction Z, the distance between the end of the film layer 112 near the tab 1112 and the end of the tab 1112 away from the film layer 112 is greater than or equal to 0.5 mm.

[0226] Understandably, after the tab 1112 is compressed, in the first direction Z, the distance between the end of the film layer 112 near the tab 1112 and the end of the tab 1112 away from the film layer 112 is greater than or equal to 0.5 mm. Wherein, the distance between the end of the film layer 112 near the tab 1112 and the end of the tab 1112 away from the film layer 112 in the first direction Z is the tab layer thickness of the tab 1112.

[0227] Specifically, after the first tab 1112a is compressed, in the first direction Z, the distance between the end of the first film layer 112a near the first tab 1112a and the end of the first tab 1112a away from the first film layer 112a is the tab layer thickness of the first tab 1112a, which is L1. Wherein, L1≥0.5mm.

[0228] After the second tab 1112b is compressed, in the first direction Z, the distance between the end of the second film layer 112b near the second tab 1112b and the end of the second tab 1112b away from the second film layer 112b is the tab layer thickness of the second tab 1112b, which is L2. Wherein, L2≥0.5mm.

[0229] The thickness of the tab layer of tab 1112 can be 0.5mm, 0.55mm, 0.6mm, 0.65mm, 0.7mm, 0.75mm, 0.8mm, etc.

[0230] After the tab 1112 is compressed, in the first direction Z, there is a large distance between the end of the film layer 112 close to the tab 1112 and the end of the tab 1112 away from the film layer 112, that is, the tab 1112 has a large tab layer thickness, which can effectively improve the problem of the tab 1112 being inserted into the main body along the bending position.

[0231] In some embodiments, please refer to Figures 6 to 9 together with other figures. Figure 8 is a cross-sectional view of the electrode assembly 1 of a cylindrical battery cell 10 provided in other embodiments of this application, specifically a schematic diagram of the electrode assembly 1 before the tab 1112 is bent. Figure 9 is an enlarged view of point D in Figure 8. The distance between the same end of any two film layers 112 near the tab 1112 along the first direction Z is less than 1.2 mm.

[0232] Understandably, when the electrode 11 is in the unfolded state, the distance between any two film layers 112 and the same end of the tab 1112 along the first direction Z is L3.

[0233] Where L3 < 1.2 mm, L3 can specifically be 0.5 mm, 0.6 mm, 0.7 mm, 0.8 mm, 0.9 mm, 1 mm, 1.1 mm, etc.

[0234] Understandably, when the first electrode 11a is in the unfolded state, the distance between the ends of the film layers 112 of any two first electrode layers 11a that are closest to the tab 1112 of the first electrode 11a along the first direction Z is L3. Specifically, when the first electrode 11a is in the unfolded state, the distance between the ends of any two first film layers 112a that are closest to the tab 1112a along the first direction Z is L3.

[0235] When the second electrode 11b is in the unfolded state, the distance between the ends of the film layers 112 of any two second electrode layers 11b that are closest to the tabs 1112 of the second electrode 11b along the first direction Z is L3. Specifically, when the second electrode 11b is in the unfolded state, the distance between the ends of any two second film layers 112b that are closest to the tabs 1112b along the first direction Z is L3.

[0236] This configuration ensures that the distance between any two membrane layers 112 and the same end of the tab 1112 in the first direction Z is small. This can improve the problem that the tab 1112 is inserted into and overlaps the electrode sheet 11 with different polarities due to the large distance between any two membrane layers 112 and the same end of the tab 1112.

[0237] In some embodiments, as shown in Figures 4 and 5, the electrode assembly 1 is provided with a central hole 101 extending along a first direction Z, and the central hole 101 passes through both ends of the electrode assembly 1 along the first direction Z.

[0238] In some embodiments, please refer to Figures 6 and 7 together, and in conjunction with other figures. The electrode assembly 1 has a winding axis L parallel to a first direction Z. In the first direction Z, the tab 1112 has a bent section 11121 at one end opposite to the current collector body 1111.

[0239] The bent section 11121 is the part of the tab 1112 that is bent relative to the current collector body 1111.

[0240] Understandably, in the first direction Z, the end of the first electrode 1112a facing away from the first current collector 1111a is provided with a bent section 11121. In the first direction Z, the end of the second electrode 1112b facing away from the second current collector 1111b is provided with a bent section 11121.

[0241] In some possible designs, as shown in Figures 6 and 7, and in conjunction with other figures, the bent segment 11121 includes a first bent portion 111211, which is bent relative to the current collector body 1111 in a direction close to the winding axis L.

[0242] The first bending section 111211 refers to the part of the bending section 11121 that is bent toward the winding axis L relative to the current collecting body 1111.

[0243] Understandably, the first bend 111211 is bent toward the center hole 101 relative to the main body 1111.

[0244] Understandably, the first bent portion 111211 of the first tab 1112a is bent relative to the first current collector 1111a in a direction close to the winding axis L, and the first bent portion 111211 of the second tab 1112b is bent relative to the second current collector 1111b in a direction close to the winding axis L.

[0245] In some possible designs, as shown in Figures 6 and 7, and in conjunction with other figures, the bent segment 11121 includes a second bent portion 111212, which is bent relative to the current collector 1111 in a direction away from the winding axis L.

[0246] The second bending section 111212 refers to the part of the bending section 11121 that is bent away from the winding axis L relative to the main body 1111.

[0247] Understandably, the second bend 111212 is bent relative to the main body 1111 in a direction away from the central hole 101.

[0248] Understandably, the second bent portion 111212 of the first tab 1112a is bent relative to the first current collector 1111a in a direction away from the winding axis L, and the second bent portion 111212 of the second tab 1112b is bent relative to the second current collector 1111b in a direction away from the winding axis L.

[0249] This configuration allows the end region of the tab 1112 facing away from the current collector 1111 along the first direction Z to be bent, thereby forming a relatively dense stacked layer Q. This facilitates welding of the tab 1112 and provides a stronger binding effect on the electrode 11, resulting in higher charge / discharge performance of the electrode assembly 1.

[0250] In some embodiments, please refer to Figures 6 and 7 together, and in conjunction with other figures. The tab 1112 may also include a straight section 11122 extending generally along a first direction Z. The straight section 11122 may be provided between the current collecting body 1111 and the bent section 11121 in the first direction Z.

[0251] The first bending portion 111211 can be bent relative to the straight section 11122 in a direction closer to the winding axis L, and the second bending portion 111212 can be bent relative to the straight section 11122 in a direction away from the winding axis L.

[0252] In some embodiments, please refer to Figures 6 and 7 together, and in conjunction with other figures. The bending segment 11121 includes at least one first bending portion 111211 and at least one second bending portion 111212, wherein the first bending portion 111211 and the second bending portion 111212 are alternately arranged along a first direction Z.

[0253] In the first electrode tab 1112a, the first bent portion 111211 and the second bent portion 111212 are alternately arranged along the first direction Z. In the second electrode tab 1112b, the first bent portion 111211 and the second bent portion 111212 are alternately arranged along the first direction Z.

[0254] This configuration allows the end region of the tab 1112 that is away from the current collector 1111 along the first direction Z to be bent, thereby forming a relatively dense stacked layer Q.

[0255] In the bending section 11121, the straight section 11122 may or may not be provided between the first bending part 111211 and the second bending part 111212.

[0256] In some embodiments, please refer to Figures 6 and 7 together, and in conjunction with other figures. The first bending portion 111211 is provided to bend radially Y along the electrode assembly 1.

[0257] Specifically, the first bending portion 111211 is bent along the radial direction Y of the electrode assembly 1 toward the winding axis L.

[0258] In some embodiments, please refer to Figures 6 and 7 together, and in conjunction with other figures. The second bending portion 111212 is provided with a radial Y-bend along the electrode assembly 1.

[0259] Specifically, the first bending portion 111211 is bent along the radial direction Y of the electrode assembly 1 toward the winding axis L.

[0260] By adopting the above technical solution, the bending section 11121 is bent radially Y, which enables the tab 1112 to be bent well.

[0261] In some other embodiments, the first bending portion 111211 may be bent along a direction intersecting the radial Y, and the second bending portion 111212 may also be bent along a direction intersecting the radial Y.

[0262] Please refer to Figures 10 to 13 together with other accompanying drawings. Figure 10 is a schematic diagram of the electrode assembly 1 shown in Figure 5 before compression; Figure 11 is an enlarged view of point E in Figure 10; Figure 12 is an enlarged view of point F in Figure 10; and Figure 13 is a flowchart of a method for processing a battery cell according to some embodiments of this application. The processing method for the cylindrical battery cell 10 provided in this application is applied to the cylindrical battery cell 10. The cylindrical battery cell 10 in this embodiment is the same as the cylindrical battery cell 10 in the above embodiments; please refer to the relevant descriptions of the cylindrical battery cell 10 in the above embodiments for details, which will not be repeated here.

[0263] The processing method for the cylindrical battery cell 10 provided in this application includes the following steps:

[0264] S10. The tabs 1112 of the first electrode 11a and the tabs 1112 of the second electrode 11b are respectively disposed at both ends of the electrode assembly 1 along the first direction Z. On the side where the tabs 1112 of the first electrode 11a are located, the film layer 112 of the first electrode 11a extends beyond the end of the second electrode 11b along the first direction Z, and the distance between the end of the film layer 112 of the first electrode 11a and the end of the second electrode 11b is ≥0.3mm.

[0265] Specifically, the first tab 1112a and the second tab 1112b are respectively disposed at both ends of the electrode assembly 1 along the first direction Z. The first film layer 112a extends beyond the second electrode 11b along the first direction Z in a direction close to the first tab 1112a, and the distance between the end of the first film layer 112a close to the first tab 1112a and the end of the second current collector 1111b away from the second tab 1112b in the first direction Z is H1, where H1 ≥ 0.3 mm.

[0266] Thus, in the first direction Z, there is a large distance between the end of the film layer 112 of the first electrode 11a near the tab 1112 of the first electrode 11a and the second electrode 11b.

[0267] S20. The first electrode 11a and the second electrode 11b are stacked and wound together.

[0268] Specifically, the first current collector 1111a, the first tab 1112a, the first membrane 112a, the second current collector 1111b, the second tab 1112b, and the second membrane 112b are all wound together.

[0269] Based on this, the electrode assembly 1 formed by winding is a winding structure.

[0270] S30, Bend the tab 1112;

[0271] Specifically, both the first tab 1112a and the second tab 1112b are bent.

[0272] Specifically, a bent section 11121 is formed at one end of the tab 1112 away from the current collector 1111 along the first direction Z. The bent section 11121 includes a first bent portion 111211 and a second bent portion 111212 that alternate along the first direction Z. The first bent portion 111211 is bent relative to the current collector 1111 in a direction close to the winding axis L, and the second bent portion 111212 is bent relative to the current collector 1111 in a direction away from the winding axis L.

[0273] Based on this, in the first direction Z, the end of the tab 1112 that is away from the current collection body 1111 is gathered and aggregated to form a relatively dense stacked layer Q, as shown in Figure 10.

[0274] S40. In the first direction Z, the tab 1112 is compressed toward the current collector 1111 of the first electrode 11a and the current collector 1111 of the second electrode 11b.

[0275] Specifically, the electrode assembly 1 is compressed in opposite directions at both ends along the first direction Z, as shown in Figure 5.

[0276] Specifically, in the first direction Z, the end of the first tab 1112a that is away from the first current collector 1111a is compressed toward the first current collector 1111a. In the first direction Z, the end of the second tab 1112b that is away from the second current collector 1111b is compressed toward the second current collector 1111b.

[0277] The method for processing a cylindrical battery cell 10 provided in this application embodiment involves, before stacking and winding the first electrode 11a and the second electrode 11b, extending the film layer 112 of the first electrode 11a beyond the end of the second electrode 11b along a first direction Z on the side where the tab 1112 of the first electrode 11a is located, and ensuring that the distance between the end of the film layer 112 of the first electrode 11a and the end of the second electrode 11b is ≥0.3mm, thereby creating a large distance between the end of the film layer 112 of the first electrode 11a and the end of the second electrode 11b on the side where the tab 1112 of the first electrode 11a is located. Thus, after the tab 1112 is compressed in step S40, after the tab 1112 of the first electrode 11a moves towards the second electrode 11b along the bending position, there is still a certain safe distance between the tab 1112 of the first electrode 11a and the second electrode 11b. This can improve the problem of short circuit in the electrode assembly 1 caused by the tab 1112 of the first electrode 11a overlapping with the second electrode 11b. Specifically, in the first direction Z, there is a large distance between the end of the first film layer 112a near the first tab 1112a and the second electrode 11b. After the compression process, after the first tab 1112a moves towards the main body along the bending position, there is still a certain safe distance between the first tab 1112a and the second electrode 11b. This can improve the problem of short circuit in the electrode assembly 1 caused by the tab 1112a overlapping with the second electrode 11b. Therefore, this helps to improve the reliability of the cylindrical battery cell 10.

[0278] In some embodiments, after step S40, the electrode assembly 1 can be assembled into the housing 2, as shown in FIG4.

[0279] In some embodiments, please refer to Figures 10 and 12 together, and in conjunction with other figures. Before stacking and winding the first electrode 11a and the second electrode 11b in step S20, the following steps are also included:

[0280] S50, on the side where the tab 1112 of the second electrode 11b is located, the film layer 112 of the second electrode 11b extends beyond the end of the first electrode 11a along the first direction Z, and the distance between the end of the film layer 112 of the second electrode 11b and the end of the first electrode 11a is ≥0.3mm.

[0281] Specifically, the second film layer 112b extends beyond the first electrode 11a along the first direction Z toward the direction of the second tab 1112b, and the distance between the end of the second film layer 112b near the second tab 1112b and the end of the first current collector 1111a away from the first tab 1112a in the first direction Z is H2, where H2 ≥ 0.3 mm.

[0282] Thus, on the side where the tab 1112 of the second electrode 11b is located, there is a large distance between the end of the film layer 112 of the second electrode 11b and the end of the first electrode 11a. After the tab 1112 is compressed in step S40, after the tab 1112 of the second electrode 11b moves towards the first electrode 11a along the bending position, there is still a certain safe distance between the tab 1112 of the second electrode 11b and the first electrode 11a, which can improve the problem of shortness in the electrode assembly 1 caused by the tab 1112 of the second electrode 11b overlapping with the first electrode 11a. Specifically, in the first direction Z, the end of the second film layer 112b near the second tab 1112b has a large distance from the first electrode 11a. After compression, even after the second tab 1112b moves towards the main body along the bending position, a certain safe distance remains between the second tab 1112b and the first electrode 11a. This improves the problem of short circuits in the electrode assembly 1 caused by overlap between the second tab 1112b and the first electrode 11a. Therefore, it helps to improve the reliability of the cylindrical battery cell 10.

[0283] In some embodiments, please refer to Figures 10 and 11 together, and in conjunction with other figures. Step S10, which involves extending the film layer 112 of the first electrode 11a beyond the end of the second electrode 11b along the first direction Z on the side where the tab 1112 of the first electrode 11a is located, includes the following steps:

[0284] S11, on the side where the tab 1112 of the second electrode 11b is located, the insulating layer 1122 of the first electrode 11a extends beyond the end of the second electrode 11b along the first direction Z.

[0285] Based on this, on the side where the tab 1112 of the second electrode 11b is located, the distance between the end of the film layer 112 of the first electrode 11a and the end of the second electrode 11b refers to the distance in the first direction Z between the end of the insulating layer 1122 near the first tab 1112a and the second current collector 1111b away from the second tab 1112b.

[0286] This configuration makes the first electrode 11a a positive electrode, which can improve the problem of inserting the tab 1112 to connect with the negative electrode after the tab 1112 of the positive electrode has been bent and compressed.

[0287] In some embodiments, please refer to Figures 10 to 12 together, and in conjunction with other figures. Step S20, which involves stacking and winding the first electrode 11a and the second electrode 11b, includes the following steps:

[0288] S21. The first electrode 11a, the second electrode 11b and the diaphragm 12 layers 112 are stacked and wound together.

[0289] Step S30, which involves bending the tab 1112, includes the following steps:

[0290] S31. The tab 1112 of the first electrode 11a is bent so that the size of the tab 1112 in the first direction Z of the first electrode 11a is ∈ [0.5mm, 3mm].

[0291] Specifically, the first tab 1112a is bent so that its dimension in the first direction Z is L4. That is, in the first direction Z, the distance between the end of the first tab 1112a away from the first current collector 1111a and the end of the first film layer 112a near the first tab 1112a is L4. In other words, in the first direction Z, the tab layer thickness of the first tab 1112a is L4. See Figure 11 for details.

[0292] Where L4∈[0.5mm, 3mm], specifically, L4 can be 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm, 1mm, 1.1mm, 1.2mm, 1.3mm, 1.4mm, 1.5mm, 1.6mm, 1.7mm, 1.8mm, 1.9mm, 2mm, 2.1mm, 2.2mm, 2.3mm, 2.4mm, 2.5mm, 2.6mm, 2.7mm, 2.8mm, 2.9mm, 3mm, etc.

[0293] S32. The tab 1112 of the second electrode 11b is bent so that the distance between the end of the tab 1112 away from the current collector 1111 and the diaphragm 12 in the first direction Z of the second electrode 11b is ∈ [0.5mm, 3mm].

[0294] Specifically, the second tab 1112b is bent such that its dimension in the first direction Z is L5. That is, in the first direction Z, the distance between the end of the second tab 1112b away from the second current collector 1111b and the end of the second film layer 112b near the second tab 1112b is L4. In other words, in the first direction Z, the tab layer thickness of the second tab 1112b is L5. See Figure 12 for details.

[0295] Where L5 ∈ [0.5mm, 3mm], specifically, L5 can be 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm, 1mm, 1.1mm, 1.2mm, 1.3mm, 1.4mm, 1.5mm, 1.6mm, 1.7mm, 1.8mm, 1.9mm, 2mm, 2.1mm, 2.2mm, 2.3mm, 2.4mm, 2.5mm, 2.6mm, 2.7mm, 2.8mm, 2.9mm, 3mm, etc.

[0296] By adopting the above technical solution, the electrode layer thickness of the electrode 1112 is smaller after bending. In this way, during the compression process of the electrode 1112, the degree of compression of the electrode 1112 in the first direction Z can be reduced, which helps the electrode 1112 to form a bent structure along the bending position during the compression process, and the problem of the bent structure being inserted into the main body is improved, which helps to improve the problem of the short length of the electrode assembly 1.

[0297] In some embodiments, please refer to Figures 4, 5, and 10 together, and in conjunction with other figures. Step S40, compressing the tab 1112 in the first direction Z toward the current collector 1111 of the first electrode 11a and the current collector 1111 of the second electrode 11b, includes the following steps:

[0298] S41. In the first direction Z, the tab 1112 of the first electrode 11a is compressed toward the current collector 1111, and the tab 1112 of the second electrode 11b is compressed toward the current collector 1111, so that the size difference of the electrode assembly 1 before and after compression is less than 4mm.

[0299] Understandably, the two ends of the compression electrode assembly 1 are aligned along the first direction Z.

[0300] In step S30, after bending the tab 1112, the dimension of the electrode assembly 1 in the first direction Z can be L6. In step S40, after compressing the tab 1112, the dimension of the electrode assembly 1 in the first direction Z is L7. The dimensions of the electrode assembly 1 before and after compression are L6-L7, where L6-L7 < 4mm. L6-L7 can be 0.5mm, 1mm, 1.5mm, 2mm, 2.5mm, 3mm, 3.5mm, 4mm, etc.

[0301] This configuration ensures that after the tab 1112 is compressed, the dimensional difference of the electrode assembly 1 before and after compression is less than 4mm, resulting in a smaller degree of compression of the tab 1112 in the first direction Z. This helps to improve the problem of the bent structure formed on the tab 1112 due to compression being inserted into the main body, thereby effectively improving the problem of the electrode assembly 1 being short due to the bending of the tab 1112.

[0302] Please refer to Figure 2 and other accompanying drawings. The battery device 100 provided in this application embodiment includes a cylindrical battery cell 10. The cylindrical battery cell 10 in this embodiment is the same as the cylindrical battery cell 10 in the above embodiments; please refer to the relevant descriptions of the cylindrical battery cell 10 in the above embodiments for details, which will not be repeated here.

[0303] The battery device 100 provided in this application embodiment, by employing the cylindrical battery cell 10 involved in the above embodiments, ensures that after the tab 1112 is compressed, and the tab 1112 of the first electrode 11a moves towards the second electrode 11b along the bending position, a certain safe distance is still maintained between the tab 1112 of the first electrode 11a and the second electrode 11b. This improves the problem of short circuits in the electrode assembly 1 caused by the tab 1112 of the first electrode 11a overlapping with the second electrode 11b. Thus, the reliability of the cylindrical battery cell 10 is improved, thereby enhancing the reliability of the battery device 100.

[0304] Please refer to Figure 1 and other accompanying drawings. The electrical device provided in this application embodiment includes a cylindrical battery cell 10 or a battery device 100. The cylindrical battery cell 10 and battery device 100 in this embodiment are the same as those in the above embodiments; please refer to the relevant descriptions of the cylindrical battery cell 10 and battery device 100 in the above embodiments for details, which will not be repeated here.

[0305] The electrical device provided in this application embodiment, by employing the cylindrical battery cell 10 or battery device 100 mentioned above, helps to improve the reliability of the cylindrical battery cell 10, thereby improving the reliability of the electrical device.

[0306] As one embodiment of this application, as shown in Figures 3 to 7, the cylindrical battery cell 10 includes a housing 2 and an electrode assembly 1 disposed within the housing 2. The electrode assembly 1 is wound along a axis L and includes a first electrode 11a and a second electrode 11b with opposite polarities. The first electrode 11a includes a first current collector 111a and a first film layer 112a. The first current collector 111a includes a first current collector body 1111a and a first tab 1112a arranged along the first direction Z. The first film layer 112a is disposed on the first current collector body 1111a. The portion of the first current collector 111a extending beyond the first film layer 112a along the first direction Z is the first tab 1112a. The first film layer 112a includes a first active material layer 1121 and an insulating layer 1122. Both the first active material layer 1121 and the insulating layer 1122 are disposed on the first current collector body 1111a. In the first direction Z, at least a portion of the insulating layer 1122 is disposed between the first active material layer 1121 and the first tab 1112a. The second electrode 11b includes a second current collector 111b and a second film layer 112b. The second film layer 112b includes a second active material layer 1123. The second current collector 111b includes a second current collector body 1111b and a second tab 1112b arranged along the first direction Z. The second active material layer 1123 is disposed on the second current collector body 1111b, and the portion of the second current collector 111b extending beyond the second active material along the first direction Z constitutes the second tab 1112b. Both the first tab 1112a and the second tab 1112b are bent. The first tab 1112a and the second tab 1112b are respectively disposed at both ends of the electrode assembly 1 along the first direction Z. In the first direction Z, the insulating layer 1122 extends beyond the second electrode 11b in a direction closer to the first tab 1112a. In the first direction Z, the distance between the end of the insulating layer 1122 near the first tab 1112a and the end of the current collector 1111b away from the second tab 1112b is H1, where H1 ≥ 0.5 mm.

[0307] The following is a detailed explanation using specific experimental data:

[0308] In the experiment, taking the first electrode 11a as the negative electrode and the second electrode 11b as the positive electrode as an example, the specific data are shown in Tables 1 and 2:

[0309] Table 1

[0310] Table 2

[0311] As can be seen from the above embodiments, when H1 ≥ 0.3 mm, the first electrode 11a and the second electrode 11b are not short-circuited; when H1 does not satisfy H1 ≥ 0.3 mm, the first electrode 11a and the second electrode 11b are short-circuited. Thus, in the first direction Z, the end of the first film layer 112a near the first tab 1112a has a large distance from the second electrode 11b. After compression, even after the first tab 1112a moves along the bending position towards the main body, a certain safe distance remains between the first tab 1112a and the second electrode 11b. This improves the problem of short circuits within the electrode assembly 1 caused by the first tab 1112a and the second electrode 11b overlapping. Therefore, this helps improve the reliability of the cylindrical battery cell 10.

[0312] In the negative electrode, when H2 ≥ 0.3 mm, the first electrode 11a and the second electrode 11b are not short-circuited; when H1 does not satisfy H2 ≥ 0.3 mm, the first electrode 11a and the second electrode 11b are short-circuited. Thus, on the side where the tab 1112 of the second electrode 11b is located, there is a large distance between the end of the second film layer 112b and the end of the first electrode 11a. After compression, even after the second tab 1112b moves along the bending position towards the main body, a certain safe distance remains between the second tab 1112b and the first electrode 11a. This improves the problem of short circuits within the electrode assembly 1 caused by the second tab 1112b and the first electrode 11a overlapping. Therefore, this helps improve the reliability of the cylindrical battery cell 10.

[0313] The above are merely preferred embodiments of this application and are not intended to limit this application. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A cylindrical battery cell (10), wherein, include: Outer shell (2); The electrode assembly (1) is at least partially disposed within the housing (2); The electrode assembly (1) has a wound structure and includes a first electrode (11a) and a second electrode (11b) with opposite polarities. Both the first electrode (11a) and the second electrode (11b) include a current collector (111) and a film layer (112) disposed on the current collector (111). The current collector (111) includes a current collector body (1111) and an electrode tab (1112) arranged along a first direction (Z). The film layer (112) is disposed on the current collector body (1111). The portion of the current collector (1111) that extends beyond the film layer (112) along the first direction (Z) is the electrode tab (1112). The electrode tab (1112) is bent and disposed at both ends of the electrode assembly (1) along the first direction (Z). Wherein, on the side where the tab (1112) of the first electrode (11a) is located, the film layer (112) of the first electrode (11a) extends beyond the end of the second electrode (11b) along the first direction (Z), and the distance between the end of the film layer (112) of the first electrode (11a) and the end of the second electrode (11b) is H1, where H1 ≥ 0.3 mm.

2. The cylindrical battery cell (10) according to claim 1, wherein, H1≥0.5mm.

3. The cylindrical battery cell (10) according to claim 1 or 2, wherein, The first electrode (11a) is a positive electrode. In the positive electrode, the film layer (112) includes a first active material layer (1121) and an insulating layer (1122). The first active material layer (1121) and the insulating layer (1122) are both disposed on the current collector (1111). In the first direction (Z), at least a portion of the insulating layer (1122) is disposed between the tab (1112) and the first active material layer (1121).

4. The cylindrical battery cell (10) according to claim 3, wherein, In the positive electrode sheet, the tensile strength of the combined structure of the insulating layer (1122) and the current collector (1111) is greater than the tensile strength of the tab (1112).

5. The cylindrical battery cell (10) according to claim 4, wherein, In the positive electrode sheet, the tensile strength of the combined structure of the insulating layer (1122) and the current collector (1111) is greater than 1.5 times the tensile strength of the tab (1112).

6. The cylindrical battery cell (10) according to any one of claims 3-5, wherein, In the positive electrode sheet, the tensile strength of the combined structure of the insulating layer (1122) and the current collector (1111) is greater than or equal to 600 MPa.

7. The cylindrical battery cell (10) according to any one of claims 3-6, wherein, A diaphragm (12) is provided between the first electrode (11a) and the second electrode (11b); In the first direction (Z), in the positive electrode sheet, the insulating layer (1122) extends beyond the diaphragm (12) in a direction close to the tab (1112), or the end of the insulating layer (1122) close to the tab (1112) is flush with the diaphragm (12).

8. The cylindrical battery cell (10) according to any one of claims 1-7, wherein, On the side where the tab (1112) of the second electrode (11b) is located, the film layer (112) of the second electrode (11b) extends beyond the end of the first electrode (11a) along the first direction (Z), and the distance between the end of the film layer (112) of the second electrode (11b) and the end of the first electrode (11a) is H2, where H2 ≥ 0.3 mm.

9. The cylindrical battery cell (10) according to claim 8, wherein, H2≥0.5mm.

10. The cylindrical battery cell (10) according to claim 8 or 9, wherein, The second electrode (11b) is a negative electrode. In the negative electrode, the film layer (112) includes a second active material layer (1123), which is disposed on the current collector (1111).

11. The cylindrical battery cell (10) according to any one of claims 8-10, wherein, The first electrode (11a) is a positive electrode, and the second electrode (11b) is a negative electrode. In the positive electrode, the film layer (112) includes a first active material layer (1121) and an insulating layer (1122). The first active material layer (1121) and the insulating layer (1122) are both disposed on the current collector (1111). In the first direction (Z), at least a portion of the insulating layer (1122) is disposed between the tab (1112) and the first active material layer (1121). The tensile strength of the combined structure of the film layer (112) of the second electrode (11b) and the current collector (1111) of the second electrode (11b) is greater than the tensile strength of the tab (1112) of the second electrode (11b), and is also greater than the tensile strength of the combined structure of the insulating layer (1122) and the current collector (1111) of the first electrode (11a).

12. The cylindrical battery cell (10) according to any one of claims 8-11, wherein, The second electrode (11b) is a negative electrode. In the negative electrode, the tensile strength of the combined structure of the film layer (112) and the current collector (1111) is greater than the tensile strength of the tab (1112) and is greater than or equal to 900 MPa.

13. The cylindrical battery cell (10) according to any one of claims 1-12, wherein, The tensile strength of the tab (1112) is less than or equal to 400 MPa.

14. The cylindrical battery cell (10) according to any one of claims 1-13, wherein, In the first direction (Z), the distance between the end of the film layer (112) near the tab (1112) and the end of the tab (1112) away from the film layer (112) is greater than or equal to 0.5 mm.

15. The cylindrical battery cell (10) according to any one of claims 1-14, wherein, The distance between any two of the membrane layers (112) near the same end of the tab (1112) along the first direction (Z) is less than 1.2 mm.

16. The cylindrical battery cell (10) according to any one of claims 1-15, wherein, The electrode assembly (1) has a winding axis (L) parallel to the first direction (Z), and in the first direction (Z), the tab (1112) has a bent section (11121) at one end away from the current collector (1111); The bending section (11121) includes a first bending portion (111211) that is bent relative to the current collecting body (1111) in a direction close to the winding axis (L), and / or, the bending section (11121) includes a second bending portion (111212) that is bent relative to the current collecting body (1111) in a direction away from the winding axis (L).

17. The cylindrical battery cell (10) according to claim 16, wherein, The bending segment (11121) includes at least one first bending portion (111211) and at least one second bending portion (111212), wherein the first bending portion (111211) and the second bending portion (111212) are alternately arranged along the first direction (Z) in the bending segment (11121).

18. The cylindrical battery cell (10) according to claim 16 or 17, wherein, The first bending portion (111211) is bent radially (Y) along the electrode assembly (1), and / or the second bending portion (111212) is bent radially (Y) along the electrode assembly (1).

19. A method for processing a cylindrical battery cell (10), applied to the cylindrical battery cell (10) according to any one of claims 1-18, wherein, The processing method of the cylindrical battery cell (10) includes: The tabs (1112) of the first electrode (11a) and the tabs (1112) of the second electrode (11b) are respectively disposed at both ends of the electrode assembly (1) along the first direction (Z). On the side where the tabs (1112) of the first electrode (11a) are located, the film layer (112) of the first electrode (11a) extends beyond the end of the second electrode (11b) along the first direction (Z), and the distance between the end of the film layer (112) of the first electrode (11a) and the end of the second electrode (11b) is ≥0.3mm. The first electrode (11a) and the second electrode (11b) are stacked and wound together; The tab (1112) is bent and configured; In the first direction (Z), the tab (1112) is compressed toward the current collector (1111) of the first electrode (11a) and the current collector (1111) of the second electrode (11b).

20. The method for processing a cylindrical battery cell (10) according to claim 19, wherein, Before stacking and winding the first electrode (11a) and the second electrode (11b), the method further includes: On the side where the tab (1112) of the second electrode (11b) is located, the film layer (112) of the second electrode (11b) extends beyond the end of the first electrode (11a) along the first direction (Z), and the distance between the end of the film layer (112) of the second electrode (11b) and the end of the first electrode (11a) is ≥0.3mm.

21. The method for processing a cylindrical battery cell (10) according to claim 19 or 20, wherein, The step of extending the film layer (112) of the first electrode (11a) beyond the end of the second electrode (11b) along the first direction (Z) on the side where the tab (1112) of the first electrode (11a) is located includes: On the side where the tab (1112) of the first electrode (11a) is located, the insulating layer (1122) of the first electrode (11a) extends beyond the end of the second electrode (11b) along the first direction (Z).

22. The processing method of the cylindrical battery cell (10) according to claim 21, wherein, The step of stacking and winding the first electrode (11a) and the second electrode (11b) includes: The first electrode (11a), the second electrode (11b), and the diaphragm (12) are stacked and wound together; The bending of the tab (1112) includes: The tab (1112) of the first electrode (11a) is bent so that the size of the tab (1112) in the first direction (Z) of the first electrode (11a) is ∈ [0.5mm, 3mm]. The tab (1112) of the second electrode (11b) is bent so that, in the first direction (Z), the distance between the end of the tab (1112) away from the current collector (1111) and the diaphragm (12) is ∈ [0.5mm, 3mm].

23. The method for processing a cylindrical battery cell (10) according to any one of claims 19-22, wherein, The compression of the tab (1112) in the first direction (Z) toward the current collector body (1111) of the first electrode (11a) and the current collector body (1111) of the second electrode (11b) includes: In the first direction (Z), the tab (1112) of the first electrode (11a) is compressed toward the current collector (1111), and the tab (1112) of the second electrode (11b) is compressed toward the current collector (1111), so that the size difference of the electrode assembly (1) before and after compression is less than 4 mm.

24. A battery device (100), wherein, Includes the cylindrical battery cell (10) according to any one of claims 1-18.

25. An electrical appliance, wherein, Includes a cylindrical battery cell (10) according to any one of claims 1-18; or includes a battery device (100) according to claim 24.

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