Cylindrical battery monomer, battery and power utilization device

Abstract

The utility model provides a cylindrical battery monomer, a battery and a power utilization device. The cylindrical battery monomer comprises a shell, an electrode assembly and a binding piece, the electrode assembly is contained in the shell and comprises an electrode body and a tab, and the tab is led out from the end of the electrode body. The binding piece is arranged between the shell and the electrode assembly, the binding piece is arranged around the peripheral side of the electrode body in the circumferential direction of the electrode body, the binding piece is provided with a first end and a second end which are arranged in the circumferential direction, and the first end and the second end are arranged at an interval. The cylindrical battery monomer provided by the embodiment of the utility model is beneficial to improving the reliability of the cylindrical battery monomer.

Description

Technical Field

[0001] The present application relates to the technical field of batteries, and more particularly, to a cylindrical battery cell, a battery, and an electrical device. Background Art

[0002] Batteries are widely used in electronic devices, such as mobile phones, laptop computers, battery cars, electric vehicles, electric airplanes, electric ships, electric toy cars, electric toy ships, electric toy airplanes, and electric tools, etc.

[0003] In the development of cylindrical battery cell technology, in addition to improving the performance of cylindrical battery cells, the reliability of cylindrical battery cells is also an issue that needs to be considered. Therefore, how to improve the reliability of cylindrical battery cells is an ongoing improvement issue in cylindrical battery cell technology. Summary of the Utility Model

[0004] The present application provides a cylindrical battery cell, a battery, and an electrical device to improve the reliability of the cylindrical battery cell.

[0005] The present application is implemented through the following technical solutions:

[0006] In a first aspect, the cylindrical battery cell provided by the embodiments of the present application includes a housing, an electrode assembly, and a binding member. The electrode assembly is accommodated in the housing. The electrode assembly includes an electrode body and an electrode tab, and the electrode tab is led out from the end of the electrode body. The binding member is disposed between the housing and the electrode assembly. The binding member is disposed around the outer peripheral side of the electrode body along the circumferential direction of the electrode body. The binding member has a first end and a second end disposed along the circumferential direction, and the first end and the second end are spaced apart.

[0007] For the cylindrical battery cell provided by the embodiments of the present application, by providing that the binding member has a first end and a second end disposed along the circumferential direction, and the first end and the second end are spaced apart, it is beneficial to reduce the risk of damage to the electrode assembly due to excessive binding force of the binding member during the expansion process, and is beneficial to improving the reliability of the cylindrical battery cell.

[0008] According to some embodiments of the present application, the circumference of the electrode body along the circumferential direction is L, and the length of the binding member along the circumferential direction is l, and 330° ≤ 2π * l / L ≤ 360°.

[0009] In the above solution, the first end and the second end are spaced apart. During the expansion of the electrode assembly, the first end and the second end can move in a direction away from each other, reducing the binding force of the restraint on the expansion force of the electrode assembly, thereby reducing the expansion stress of the electrode assembly and reducing the risk of damage to the electrode assembly during expansion. And setting 330°≤2π*l / L is beneficial to reducing the risk of scratching the surface of the electrode assembly exposed to the outside of the restraint through the area between the first end and the second end during the process of installing the electrode assembly into the housing. Additionally, during the process of injecting electrolyte into the cylindrical battery cell, the electrolyte can enter the interior of the electrode assembly through the exposed area, which is beneficial to improving the wettability of the electrolyte to the electrode assembly.

[0010] According to some embodiments of the present application, the restraint includes an adhesive layer and a substrate layer. The adhesive layer is located between the substrate layer and the electrode body and adhesively connects the substrate layer and the electrode body.

[0011] In the above solution, setting the restraint to include an adhesive layer and a substrate layer is beneficial to improving the restraint effect of the restraint on the electrode assembly, reducing the risk of deformation such as loosening of the electrode assembly, and at the same time, it is also beneficial to reasonably set the structural strength of the substrate area according to the required bearing capacity of the restraint.

[0012] According to some embodiments of the present application, the adhesive layer includes a pressure-sensitive adhesive.

[0013] In the above solution, the pressure-sensitive adhesive has excellent adhesive properties and low sensitivity to temperature. Whether in high-temperature or low-temperature environments, it can exhibit good adhesive properties, which is beneficial to improving the bonding reliability between the restraint and the electrode body. Moreover, the pressure-sensitive adhesive does not require heating and can be used directly, making the bonding of the restraint and the electrode body more convenient.

[0014] According to some embodiments of the present application, the material of the substrate layer includes polyethylene terephthalate.

[0015] In the above solution, polyethylene terephthalate has excellent mechanical properties, such as creep resistance, fatigue resistance, and abrasion resistance, and polyethylene terephthalate has high toughness. Thus, under the repeated action of the expansion force of the electrode assembly, it can still maintain good mechanical properties. Additionally, polyethylene terephthalate has high corrosion resistance, which is beneficial to reducing the risk of the restraint failing due to corrosion by the electrolyte.

[0016] According to some embodiments of the present application, the thickness e of the restraint satisfies: 30μm≤e≤60μm.

[0017] In the above solution, setting 30μm ≤ e ≤ 60μm is beneficial to improving the energy density of the cylindrical battery cell while reducing the risk of the binding member wrinkling, and thus beneficial to improving the product yield of the cylindrical battery cell.

[0018] According to some embodiments of the present application, the electrode body has a middle cross-section, the electrode body is symmetrically arranged relative to the middle cross-section along the axial direction of the electrode body, and at least one binding member covers the middle cross-section.

[0019] In the above solution, setting at least one binding member to cover the middle cross-section enables the binding member to exert a binding effect when the electrode assembly just starts to expand, which is beneficial to the binding effect of the binding member on the expansion force of the cylindrical battery cell, reduces the risk of the electrode assembly expanding freely and generating wrinkles, and is beneficial to further improving the reliability of the cylindrical battery cell.

[0020] According to some embodiments of the present application, the dimension of the binding member along the axial direction of the electrode body is d, and the dimension of the electrode body along the axial direction is D, where 0.75 ≤ d / D ≤ 1.

[0021] In the above solution, setting 0.75 ≤ d / D ≤ 1 is beneficial to improving the consistency of the binding force of the binding member on the electrode assembly, and thus beneficial to improving the consistency and stability of the performance of the electrode assembly.

[0022] According to some embodiments of the present application, the number of binding members is one.

[0023] In the above solution, during the process of loading the binding member together with the electrode assembly into the housing, it is beneficial to reduce the risk of the binding member rubbing against the housing, and thus beneficial to improving the product yield of the cylindrical battery cell.

[0024] According to some embodiments of the present application, the number of binding members is multiple, and the multiple binding members are arranged at intervals along the axial direction of the electrode body.

[0025] In the above solution, the space along the axial direction between two adjacent binding members can provide space for the expansion of the electrode assembly, and the position of the binding member and its corresponding central angle can be reasonably set according to the specific position during the expansion process of the electrode assembly, which is beneficial to further improving the reliability of the cylindrical battery cell.

[0026] According to some embodiments of the present application, the material of the outer shell includes carbon steel or stainless steel.

[0027] In the above solution, both carbon steel and stainless steel have good corrosion resistance. Setting the material of the outer shell to include carbon steel and stainless steel is beneficial to improving the corrosion resistance of the outer shell.

[0028] According to some embodiments of the present application, the binding member is made of an insulating material.

[0029] In the above solution, the binding member is made of an insulating material, which helps reduce the risk of internal short circuit in the cylindrical battery cell caused by the contact between the binding member and the electrode assembly, and also helps reduce the risk of corrosion of the binding member.

[0030] According to some embodiments of the present application, the electrode assembly includes a first electrode tab, the first electrode tab includes a first active material layer and a tab, the first active material layer includes a matrix region and a thinned region, the thickness of the thinned region is less than that of the matrix region, and the thinned region is located on the side of the matrix region close to the tab. The electrode body includes a first part and a second part distributed along its own axial direction, the first part includes the thinned region, the second part includes the matrix region, and the outer diameter of the first part is less than that of the second part.

[0031] In the above solution, by reducing the thickness of the thinned region relative to the matrix region, during the cold pressing process of the first electrode tab, the stress concentration at the edge of the thinned region away from the matrix region, that is, the axial end of the electrode body, can be reduced, and the risk of fracture of the first electrode tab can be reduced.

[0032] According to some embodiments of the present application, the cylindrical battery cell further includes an insulating member, the insulating member is wound around the circumference of the tab, and along the radial direction of the electrode body, the insulating member and the binding member have an overlapping portion, and the overlapping portion is correspondingly arranged with the first part.

[0033] In the above solution, it is beneficial to improve the binding effect of the binding member on the electrode body, and arranging the overlapping portion of the binding member and the insulating member corresponding to the first part is beneficial to reducing the additional space occupied by the overlapping portion of the insulating member and the binding member in the radial direction inside the housing, beneficial to improving the space utilization rate inside the housing, and further beneficial to improving the energy density of the cylindrical battery cell.

[0034] According to some embodiments of the present application, along the radial direction of the electrode body, the distance between the outer surface of the overlapping portion and the housing is greater than the distance between the outer surface of the portion of the binding member corresponding to the second part and the housing.

[0035] In the above solution, during the process of installing the electrode assembly into the housing, it is beneficial to reduce the risk of rubbing between the overlapping portion and the housing, and beneficial to improving the product yield of the cylindrical battery cell.

[0036] According to some embodiments of the present application, the outer diameter of the first part is d1, the outer diameter of the second part is d2, the thickness of the insulating member is t1, and d1 + 2t1 ≤ d2.

[0037] In the above solution, when the insulating member and the binding member overlap at the first part, setting d1 + 2t1 ≤ d2 is beneficial to reducing the risk of rubbing between the overlapping portion and the housing during the process of installing the electrode assembly into the housing, and beneficial to improving the product yield of the cylindrical battery cell.

[0038] In a second aspect, the battery provided in the embodiments of the present application includes the cylindrical battery cell provided in any of the above embodiments.

[0039] Since the battery provided in the embodiments of the present application adopts the cylindrical battery cell provided in any of the above embodiments, it has the same technical effects.

[0040] In a third aspect, the electrical device provided in the embodiments of the present application includes the cylindrical battery cell or battery provided in any of the above embodiments, and the battery is used to provide electrical energy.

[0041] Since the electrical device provided in the embodiments of the present application adopts the cylindrical battery cell or battery provided in any of the above embodiments, it has the same technical effects, which will not be elaborated herein.

[0042] Additional aspects and advantages of the present application will be partially given in the following description, partially become apparent from the following description, or be understood through the practice of the present application. Description of the Drawings

[0043] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present application, and thus should not be regarded as limiting the scope. For those of ordinary skill in the art, other related drawings can also be obtained based on these drawings without creative efforts.

[0044] Figure 1 It is a schematic structural diagram of a vehicle provided in the embodiments of the present application;

[0045] Figure 2 It is a schematic structural diagram of a battery provided in the embodiments of the present application;

[0046] Figure 3 It is a schematic structural diagram of a battery module in the battery provided in the embodiments of the present application;

[0047] Figure 4 It is a schematic explosion structure diagram of a cylindrical battery cell in the battery provided in the embodiments of the present application;

[0048] Figure 5 It is a schematic cross-sectional structure diagram of a cylindrical battery cell provided in the embodiments of the present application;

[0049] Figure 6 It is a schematic cross-sectional structure diagram of an electrode body and a binding member in a cylindrical battery cell provided in the embodiments of the present application;

[0050] Figure 7 It is a schematic front view structure diagram of an electrode assembly and a binding member in a cylindrical battery cell provided in the embodiments of the present application;

[0051] Figure 8 Another schematic diagram of the explosion structure of a cylindrical battery cell provided by an embodiment of the present application;

[0052] Figure 9 A cross-sectional structure schematic diagram of a partial structure of an electrode assembly in a cylindrical battery cell provided by an embodiment of the present application;

[0053] Figure 10 A schematic diagram of the structure of a cylindrical battery cell with some structures omitted provided by an embodiment of the present application;

[0054] Figure 11 Another schematic diagram of the structure of a cylindrical battery cell with some structures omitted provided by an embodiment of the present application.

[0055] In the drawings, the drawings are not necessarily drawn to scale.

[0056] Explanation of reference numerals:

[0057] 1 - Vehicle;

[0058] 10 - Battery; 11 - Box; 111 - First sub-box; 112 - Second sub-box; 1a - Motor; 1b - Controller;

[0059] 20 - Battery module;

[0060] 30 - Cylindrical battery cell; 31 - Outer shell; 311 - Housing; 312 - End cap; 32 - Electrode assembly; 321 - Electrode body; 321a - Exposed area; 3211 - First part; 3212 - Second part; 322 - Tab; 323 - First electrode plate; 3231 - First active material layer; 3231a - Matrix area; 3231b - Thinned area;

[0061] 40 - Binding member; 40a - First end; 40b - Second end; 41 - Adhesive layer; 42 - Base material layer;

[0062] 50 - Insulating member;

[0063] X - Axial direction; Y - Circumferential direction. Detailed implementation manners

[0064] To make the objectives, technical solutions, and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are some, but not all, of the embodiments of the present application. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present application without creative efforts shall fall within the protection scope of the present application.

[0065] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as commonly understood by those skilled in the technical field to which this application belongs; the terms used in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" and any variations thereof in the specification, claims, and the above drawings of this application are intended to cover non-exclusive inclusion. The terms "first", "second", etc. in the specification, claims, or the above drawings of this application are used to distinguish different objects and not to describe a specific order or primary-secondary relationship.

[0066] Reference to "embodiment" in this application means that a specific feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of this application. The phrase appearing at various positions in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described in this application can be combined with other embodiments.

[0067] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", "joined", and "attached" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0068] The term "and / or" in this application is merely a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " in this application generally represents an "or" relationship between the associated objects before and after.

[0069] The term "a plurality of" as used in this application refers to two or more (including two). Similarly, "a plurality of groups" refers to two or more groups (including two groups), and "a plurality of sheets" refers to two or more sheets (including two sheets).

[0070] In some embodiments, the battery can be a battery module. When there are a plurality of cylindrical battery cells, the plurality of cylindrical battery cells are arranged and fixed to form a battery module.

[0071] In some embodiments, the battery can be a battery pack. The battery pack includes a box body and cylindrical battery cells, and the cylindrical battery cells or the battery module are accommodated in the box body.

[0072] In some embodiments, the box body can be part of the chassis structure of a vehicle. For example, part of the box body can become at least part of the vehicle floor, or part of the box body can become at least part of the cross beams and longitudinal beams of the vehicle.

[0073] In some embodiments, the battery can be an energy storage device. The energy storage device includes an energy storage container, an energy storage electrical cabinet, etc.

[0074] In the embodiments of the present application, the cylindrical battery cell can be a secondary battery, which refers to a cylindrical battery cell that can be activated by charging after discharging so that the active material can be used continuously.

[0075] The cylindrical battery cell can be, but is not limited to, a lithium-ion battery, a sodium-ion battery, a sodium-lithium-ion battery, a lithium metal battery, a sodium metal battery, a lithium-sulfur battery, a magnesium-ion battery, a nickel-metal hydride battery, a nickel-cadmium battery, a lead-acid battery, etc.

[0076] The cylindrical battery cell generally includes an electrode assembly. The electrode assembly includes a positive electrode, a negative electrode, and a separator. During the charge and discharge process of the cylindrical battery cell, active ions (such as lithium ions) are embedded and extracted back and forth between the positive electrode and the negative electrode. The separator is arranged between the positive electrode and the negative electrode, which can play a role in preventing the short circuit between the positive and negative electrodes, and at the same time allow the active ions to pass through.

[0077] In some embodiments, the positive electrode can be a positive electrode sheet, and the positive electrode sheet can include a positive electrode current collector and a positive electrode active material provided on at least one surface of the positive electrode current collector.

[0078] As an example, the positive electrode current collector has two surfaces opposite to each other in its own thickness direction, and the positive electrode active material is provided on any one or both of the two opposite surfaces of the positive electrode current collector.

[0079] As an example, the positive electrode current collector can be a metal foil or a composite current collector. For example, as the metal foil, stainless steel with silver plating on the surface, stainless steel, copper, aluminum, nickel, carbon electrode, carbon, nickel or titanium, etc. can be used. The composite current collector can include a polymer material base layer and a metal layer. The composite current collector can be formed by forming a metal material (such as aluminum, aluminum alloy, nickel, nickel alloy, titanium, titanium alloy, silver and silver alloy, etc.) on a polymer material substrate (such as a substrate of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0080] As an example, the positive electrode active material can include at least one of the following materials: lithium-containing phosphate, lithium transition metal oxide, and their respective modified compounds. However, the present application is not limited to these materials, and other traditional materials that can be used as battery positive electrode active materials can also be used.

[0081] In some embodiments, the negative electrode may be a negative electrode sheet, and the negative electrode sheet may include a negative electrode current collector.

[0082] As an example, the negative electrode current collector may be a metal foil or a composite current collector. For example, as the metal foil, aluminum with a silver-plated surface, stainless steel with a silver-plated surface, stainless steel, copper, aluminum, nickel, carbon electrodes, carbon, nickel, or titanium, etc. may be used.

[0083] In some embodiments, the negative electrode current collector has two surfaces opposite to each other in its own thickness direction, and the negative electrode active material is disposed on any one or both of the two opposite surfaces of the negative electrode current collector.

[0084] As an example, the negative electrode active material may be a negative electrode active material for a battery well-known in the art. As an example, the negative electrode active material may include at least one of the following materials: artificial graphite, natural graphite, soft carbon, hard carbon, silicon-based materials, tin-based materials, and lithium titanate, etc. The silicon-based material may be selected from at least one of elemental silicon, silicon oxides, silicon-carbon composites, silicon-nitrogen composites, and silicon alloys. The tin-based material may be selected from at least one of elemental tin, tin oxides, and tin alloys. However, the present application is not limited to these materials, and other conventional materials that can be used as the negative electrode active material of the battery may also be used. These negative electrode active materials may be used alone or in combination of two or more.

[0085] In some embodiments, the separator is a separator membrane. The present application has no particular limitation on the type of the separator membrane, and any well-known porous structure separator membrane with good chemical stability and mechanical stability may be selected.

[0086] As an example, the main material of the separator membrane may be selected from at least one of glass fiber, non-woven fabric, polyethylene, polypropylene, polyvinylidene fluoride, and ceramics. The separator membrane may be a single-layer film or a multi-layer composite film, without particular limitation. When the separator membrane is a multi-layer composite film, the materials of each layer may be the same or different, without particular limitation. The separator may be a single component located between the positive and negative electrodes, or may be attached to the surfaces of the positive and negative electrodes.

[0087] In some embodiments, the separator is a solid electrolyte. The solid electrolyte is disposed between the positive electrode and the negative electrode, and simultaneously functions to transport ions and isolate the positive and negative electrodes.

[0088] In some embodiments, the electrode assembly is a wound structure. The positive electrode sheet and the negative electrode sheet are wound into a wound structure.

[0089] In some embodiments, the electrode assembly is a stacked structure.

[0090] In some embodiments, the cylindrical battery cell may include a housing. The housing is used to encapsulate components such as the electrode assembly and the electrolyte. The housing can be a steel shell, an aluminum shell, a plastic shell (such as polypropylene), a composite metal shell (such as a copper-aluminum composite housing), or an aluminum-plastic film, etc.

[0091] In some embodiments, the housing includes an end cap and a housing body. The housing body is provided with an opening, and the end cap closes the opening to form a sealed space for accommodating substances such as the electrode assembly and the electrolyte. The housing body may be provided with one or more openings. The end cap may also be provided with one or more.

[0092] In some embodiments, at least one electrode terminal is provided on the housing, and the electrode terminal is electrically connected to the tab of the electrode assembly. The electrode terminal can be directly connected to the tab or indirectly connected to the tab through a current collector. The electrode terminal can be provided on the end cap or on the housing body.

[0093] In some embodiments, a safety valve is provided on the housing. The safety valve is used to release the internal pressure of the cylindrical battery cell.

[0094] The housing body and the electrode assembly of the cylindrical battery cell are generally cylindrical. During the preparation of the cylindrical battery cell, after the electrode assembly is manufactured, a restraint is usually provided at the cutting position of the separator of the electrode assembly to fix the separator. And during the operation of the cylindrical battery cell, it can provide a certain restraint for the expansion force of the electrode assembly, reducing the risk of excessive expansion and deformation of the cylindrical battery cell.

[0095] However, in the related art, if the restraint is provided around the entire circumference of the electrode assembly and is of a closed design, the variation range of the restraint force of the restraint on the electrode assembly is small. Then, when the expansion amount of the electrode assembly is large, the restraint force of the restraint on the electrode assembly is too large, easily causing problems of deterioration of the performance of the electrode assembly. And if the restraint is non-closed along the circumferential direction of the electrode assembly and the circumferential area around the electrode assembly is small, then during the process of inserting the electrode assembly into the housing, the separator of the part not covered by the restraint is easily rubbed against the housing body of the cylindrical battery cell, causing damage to the separator. Therefore, whether the circumferential area of the restraint around the electrode assembly is too large or too small will affect the reliable performance of the cylindrical battery cell.

[0096] In view of this, an embodiment of the present application provides a cylindrical battery cell. The cylindrical battery cell includes a housing, an electrode assembly, and a restraint. The electrode assembly is accommodated in the housing. The electrode assembly includes an electrode body and a tab, and the tab is led out from the end of the electrode body. The restraint is provided between the housing and the electrode assembly. The restraint is arranged around the outer peripheral side of the electrode body along the circumferential direction of the electrode body. The restraint has a first end and a second end arranged along the circumferential direction, and the first end and the second end are spaced apart.

[0097] For the cylindrical battery cell provided in the embodiment of the present application, the binding member has a first end and a second end arranged circumferentially, and the first end and the second end are arranged at intervals, which is beneficial to reducing the risk of damage to the electrode assembly due to excessive binding force of the binding member during expansion, and is beneficial to improving the reliable performance of the cylindrical battery cell.

[0098] The technical solutions described in the embodiments of the present application are applicable to cylindrical battery cells, batteries including cylindrical battery cells, and electrical devices using the batteries.

[0099] The battery disclosed in the embodiments of the present application can be used, but is not limited to, electrical devices such as vehicles, ships, or aircraft. The power system of the electrical device can be composed of the batteries disclosed in the present application.

[0100] The embodiments of the present application provide an electrical device using a battery as a power source. The electrical device can be, but is not limited to, a mobile phone, a tablet computer, a laptop computer, an electric toy, an electric tool, an electric bicycle, an electric motorcycle, an electric vehicle, a ship, a spacecraft, and so on. Among them, the electric toy can include a fixed or mobile electric toy, for example, a game console, an electric vehicle toy, an electric ship toy, and an electric aircraft toy, etc. The spacecraft can include an airplane, a rocket, a space shuttle, and a spaceship, etc.

[0101] For the convenience of description in the following embodiments, a vehicle 1 as an electrical device in an embodiment of the present application is taken as an example for description.

[0102] Please refer to Figure 1 , Figure 1 which is a schematic structural diagram of a vehicle provided for some embodiments of the present application. The vehicle 1 can be a fuel vehicle, a gas vehicle, or a new energy vehicle. The new energy vehicle can be a pure electric vehicle, a hybrid vehicle, or an extended-range vehicle, etc. A battery 10 is arranged inside the vehicle 1, and the battery 10 can be arranged at the bottom, head, or tail of the vehicle 1. The battery 10 can be used for power supply of the vehicle 1. For example, the battery 10 can be used as an operating power source of the vehicle 1 for the electrical system of the vehicle 1, such as for the working power requirements during the start, navigation, and operation of the vehicle 1.

[0103] The vehicle 1 may further include a controller 1b and a motor 1a. The controller 1b is used to control the battery 10 to supply power to the motor 1a, for example, for the working power requirements during the start, navigation, and driving of the vehicle 1.

[0104] In some embodiments of the present application, the battery 10 can not only be used as an operating power source of the vehicle 1, but also be used as a driving power source of the vehicle 1, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1.

[0105] Please refer to Figure 2 and Figure 3 ,Figure 2 An exploded view of the battery 10 provided by some embodiments of the present application Figure 3 A schematic structural view of the battery module 20 in the battery 10 provided by an embodiment of the present application. The battery 10 includes a box body 11 and cylindrical battery cells 30, and the cylindrical battery cells 30 are accommodated in the box body 11. Among them, the box body 11 is used to provide an accommodation space for the cylindrical battery cells 30, and the box body 11 can adopt various structures. In some embodiments, the box body 11 may include a first sub-box body 111 and a second sub-box body 112. The first sub-box body 111 and the second sub-box body 112 cover each other, and the first sub-box body 111 and the second sub-box body 112 jointly define an accommodation space for accommodating the cylindrical battery cells 30. The second sub-box body 112 may be a hollow structure with one end open, and the first sub-box body 111 may be a plate-like structure. The first sub-box body 111 covers the open side of the second sub-box body 112 so that the first sub-box body 111 and the second sub-box body 112 jointly define an accommodation space; the first sub-box body 111 and the second sub-box body 112 may also both be hollow structures with one side open, and the open side of the first sub-box body 111 covers the open side of the second sub-box body 112.

[0106] In the battery 10, there may be multiple cylindrical battery cells 30, and the multiple cylindrical battery cells 30 may be connected in series, in parallel, or in a mixed connection. A mixed connection means that there are both series and parallel connections among the multiple cylindrical battery cells 30. The multiple cylindrical battery cells 30 may be directly connected in series, in parallel, or in a mixed connection together, and then the whole formed by the multiple cylindrical battery cells 30 is accommodated in the box body 11; of course, the battery 10 may also be in the form that multiple cylindrical battery cells 30 are first connected in series, in parallel, or in a mixed connection to form battery modules 20, and then the multiple battery modules 20 are connected in series, in parallel, or in a mixed connection to form a whole and are accommodated in the box body 11. The battery 10 may further include other structures. For example, the battery 10 may further include a busbar component for realizing the electrical connection among the multiple cylindrical battery cells 30.

[0107] Among them, the cylindrical battery cell 30 may be a secondary battery or a primary battery; the cylindrical battery cell 30 may also be a lithium-sulfur battery, a sodium-ion battery, or a magnesium-ion battery, but is not limited thereto.

[0108] Please refer to Figure 4 , Figure 4 An exploded view of the cylindrical battery cell 30 in the battery 10 provided by some embodiments of the present application. As Figure 4 shown, the cylindrical battery cell 30 includes a housing 31, an electrode assembly 32, and electrode terminals. The housing 31 includes a shell 311 and an end cap 312. The shell 311 has an opening, and the end cap 312 closes the opening to isolate the internal environment of the cylindrical battery cell 30 from the external environment.

[0109] The housing 311 is a component for cooperating with the end cap 312 to form the internal environment of the cylindrical battery cell 30. Among them, the formed internal environment can be used to accommodate the electrode assembly 32, the electrolyte, and other components. The housing 311 and the end cap 312 can be independent components. The housing 311 can be of various shapes and sizes. Specifically, the shape of the housing 311 can be determined according to the specific shape and size of the electrode assembly 32. The material of the housing 311 can be various, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc.

[0110] The end cap 312 refers to a component that covers the opening of the housing 311 to isolate the internal environment of the cylindrical battery cell 30 from the external environment. Without limitation, the shape of the end cap 312 can be adapted to the shape of the housing 311 to cooperate with the housing 311. Optionally, the end cap 312 can be made of a material with a certain hardness and strength (such as aluminum alloy). In this way, the end cap 312 is not easily deformed when subjected to extrusion and collision, enabling the cylindrical battery cell 30 to have higher structural strength and improved reliability. Functional components such as electrode terminals can be provided on the end cap 312. The electrode terminals can be used to electrically connect to the electrode assembly 32 for outputting or inputting the electrical energy of the cylindrical battery cell 30. The material of the end cap 312 can also be various, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., and the embodiments of the present application do not make special restrictions on this.

[0111] In some embodiments, an insulating structure can also be provided on the inner side of the end cap 312. The insulating structure can be used to isolate the electrical connection components in the housing 311 from the end cap 312 to reduce the risk of short circuit. Exemplarily, the insulating structure can be plastic, rubber, etc.

[0112] The electrode assembly 32 is a component in the cylindrical battery cell 30 where an electrochemical reaction occurs. The housing 311 can contain one or more electrode assemblies 32. The electrode assembly 32 is mainly formed by winding a positive electrode plate and a negative electrode plate, and usually an isolation film is provided between the positive electrode plate and the negative electrode plate. The isolation film is used to separate the positive electrode plate and the negative electrode plate to reduce the risk of internal short circuit between the positive electrode plate and the negative electrode plate. The positive electrode plate includes a positive electrode body and a positive electrode tab. At least part of the positive electrode body is coated with an active material layer, and at least part of the positive electrode tab is not coated with an active material layer. The negative electrode plate includes a negative electrode body and a negative electrode tab. At least part of the negative electrode body is coated with an active material layer, and at least part of the negative electrode tab is not coated with an active material layer. The positive electrode body, the negative electrode body, and the isolation film form the electrode body. The positive electrode tab and the negative electrode tab can be located at one end of the electrode body 321 together or at both ends of the electrode body 321 respectively. During the charging and discharging process of the cylindrical battery cell 30, the positive active material and the negative active material react with the electrolyte, and the tabs 322 connect to the electrode terminals to form a current loop.

[0113] In a first aspect, as Figure 4 and Figure 5 shown, the cylindrical battery cell 30 provided by the embodiments of the present application includes a housing 31, an electrode assembly 32, and a binding member 40. The electrode assembly 32 is accommodated in the housing 31. The electrode assembly 32 includes an electrode body 321 and an electrode tab 322. The electrode tab 322 is led out from the end of the electrode body 321. The binding member 40 is disposed between the housing 31 and the electrode assembly 32. The binding member 40 is disposed around the outer peripheral side of the electrode body 321 along the circumferential direction Y of the electrode body 321. The binding member 40 has a first end 40a and a second end 40b disposed along the circumferential direction Y. The first end 40a and the second end 40b are spaced apart.

[0114] The housing 31 and the electrode assembly 32 of the cylindrical battery cell 30 may both be cylindrical, and the electrode plates of the electrode assembly 32 may be wound type.

[0115] Optionally, the electrode assembly 32 may include one electrode tab 322, or the electrode assembly 32 includes two electrode tabs 322. In an embodiment where the electrode assembly 32 includes two electrode tabs 322, the two electrode tabs 322 may be led out from one end of the electrode body 321, or the two electrode tabs 322 may be respectively led out from both ends of the electrode body 321, and can be selected according to needs.

[0116] The cylindrical battery cell 30 includes a binding member 40. Optionally, the cylindrical battery cell 30 may include one, two, or more binding members 40. The multiple binding members 40 may be spaced apart along the axial direction X of the electrode body 321, or may be adjacent to each other. The sizes of different binding members 40 along the axial direction X of the electrode body 321 may be the same or different.

[0117] Since the binding member 40 is disposed between the housing 31 and the electrode assembly 32, during the charging and discharging process of the cylindrical battery cell 30, the binding member 40 may be in contact with both the inner wall of the housing 31 and the circumferential side of the electrode body 321, or the binding member 40 may be in contact with either the circumferential side of the electrode body 321 or the interior of the housing 31, or the binding member 40 is spaced apart from both the housing 31 and the electrode body 321. Subsequently, as the number of charge-discharge cycles of the cylindrical battery cell 30 increases, the electrode assembly 32 gradually expands, and finally the binding member 40 abuts between the circumferential side of the electrode body 321 and the inner wall of the housing 31 to provide a certain binding force to the electrode body 321.

[0118] The first end 40a and the second end 40b are spaced apart. The first end 40a and the second end 40b are circumferentially spaced apart along the circumferential direction Y, and the distance between the first end 40a and the second end 40b can be set as required. The first end 40a and the second end 40b can be abutted or in contact. Optionally, the restraint member 40 can have one, two, three or more first ends 40a and second ends 40b.

[0119] The first end 40a and the second end 40b are spaced apart. When the expansion force of the electrode assembly 32 is relatively large, the first end 40a and the second end 40b can move in a direction away from each other to reduce the binding force of the restraint member 40 on the expansion force of the electrode assembly 32, thereby reducing the expansion stress of the electrode assembly 32 and reducing the risk of damage to the electrode assembly 32 during expansion.

[0120] In the cylindrical battery cell 30 provided by the embodiment of the present application, by providing that the restraint member 40 has a first end 40a and a second end 40b arranged along the circumferential direction Y, and the first end 40a and the second end 40b are spaced apart, it is beneficial to reduce the risk of damage to the electrode assembly 32 due to excessive binding force of the restraint member 40 during expansion, and is beneficial to improving the reliable performance of the cylindrical battery cell 30.

[0121] In some embodiments, as Figure 4 shown, the circumference of the electrode body 321 along the circumferential direction Y is L, and the length of the restraint member 40 along the circumferential direction Y is l, and 330° ≤ 2π * l / L ≤ 360°.

[0122] The circumference L of the electrode assembly 32 along the circumferential direction Y can be the length of the outer surface of the electrode body 321 along the circumferential direction Y for one week, and the length l of the restraint member 40 along the circumferential direction Y can be the length after the restraint member 40 is unfolded along the circumferential direction Y.

[0123] 2π * l / L can be the central angle of the restraint member 40 relative to the electrode body 321. If 330° ≤ 2π * l / L ≤ 360°, then optionally, 2π * l / L can be 330°, 335°, 340°, 345°, 350°, 355° or 360°, etc. In other words, there is no overlapping part at both ends of the restraint member 40 along the circumferential direction Y of the electrode body 321. And because the restraint member 40 has a first end 40a and a second end 40b arranged along the circumferential direction Y, and the first end 40a and the second end 40b are spaced apart, the first end 40a and the second end 40b can be in contact with each other, but not connected. In this way, during the expansion of the electrode assembly 32, under the action of the expansion force of the electrode assembly 32, the first end 40a and the second end 40b move away from each other, and the electrode assembly 32 expands outwards to reduce the binding force of the restraint member 40 on the electrode assembly 32.

[0124] The first end 40a and the second end 40b may be spaced apart. Correspondingly, 2π*l / L is less than 360°; alternatively, the first end 40a and the second end 40b may abut or contact each other. Correspondingly, 2π*l / L is equal to 360°.

[0125] Through systematic analysis and long-term research, the inventors found that when 2π*l / L ≤ 360° and the restraint member 40 has a first end 40a and a second end 40b which are spaced apart, in the case where the expansion force of the electrode assembly 32 is relatively large, the first end 40a and the second end 40b can move away from each other to reduce the restraint force of the restraint member 40 on the expansion force of the electrode assembly 32, thereby reducing the expansion stress of the electrode assembly 32 and the risk of damage to the electrode assembly 32 during expansion. And when 330° ≤ 2π*l / L is set, during the process of installing the electrode assembly 32 into the housing 311, it is beneficial to reduce the risk of scratching the surface of the electrode assembly 32 exposed outside the restraint member 40 through the area between the first end 40a and the second end 40b. Additionally, during the process of injecting electrolyte into the cylindrical battery cell 30, the electrolyte can enter the interior of the electrode assembly 32 through the exposed area 321a, which is beneficial to improving the wettability of the electrolyte to the electrode assembly 32.

[0126] In some embodiments, as Figure 6 shown, the restraint member 40 includes an adhesive layer 41 and a substrate layer 42. The adhesive layer 41 is located between the substrate layer 42 and the electrode body 321 and adhesively connects the substrate layer 42 and the electrode body 321.

[0127] The substrate layer 42 may include a material with a certain structural strength. According to the required load-bearing capacity of the restraint member 40, the material and structure of the substrate layer 42 are set so that the restraint member 40 can withstand the repeated changes in the expansion force of the electrode assembly 32. And the adhesive layer 41 can achieve the adhesive connection between the substrate layer 42 and the electrode body 321, which is beneficial to improving the restraint effect of the restraint member 40 on the electrode assembly 32 and reducing the risk of deformation such as loosening of the electrode assembly 32.

[0128] Therefore, setting the restraint member 40 to include the adhesive layer 41 and the substrate layer 42 is beneficial to improving the restraint effect of the restraint member 40 on the electrode assembly 32 and reducing the risk of deformation such as loosening of the electrode assembly 32, while also being beneficial to reasonably setting the structural strength of the substrate area according to the required load-bearing capacity of the restraint member 40.

[0129] In some embodiments, the adhesive layer 41 includes a pressure-sensitive adhesive.

[0130] The pressure-sensitive adhesive has excellent adhesive properties and low sensitivity to temperature. It can exhibit good adhesive properties both in high-temperature and low-temperature environments, which is beneficial to improving the bonding reliability between the binding member 40 and the electrode body 321. Moreover, the pressure-sensitive adhesive does not need to be heated and can be used directly, making the bonding between the binding member 40 and the electrode body 321 more convenient.

[0131] In some embodiments, the material of the base layer 42 includes polyethylene terephthalate.

[0132] Polyethylene terephthalate has excellent mechanical properties, such as creep resistance, fatigue resistance, and abrasion resistance. Moreover, polyethylene terephthalate has high toughness. Thus, when the binding member 40 is repeatedly subjected to the expansion force of the electrode assembly 32, it can still maintain good mechanical properties. Additionally, polyethylene terephthalate has high corrosion resistance, which is beneficial to reducing the risk of the binding member 40 failing due to being corroded by the electrolyte.

[0133] In some embodiments, as Figure 6 shown, the thickness e of the binding member 40 satisfies: 30μm ≤ e ≤ 60μm.

[0134] Optionally, the thickness e of the binding member 40 can be 30μm, 35μm, 40μm, 45μm, 50μm, 55μm, or 60μm, etc.

[0135] It can be understood that the smaller the thickness e of the binding member 40, the more beneficial it is to improve the energy density of the cylindrical battery cell 30. To a certain extent, the larger the thickness e of the binding member 40, the more beneficial it is to reduce the risk of the binding member 40 wrinkling during the process of attaching to the surface of the electrode body 321, thereby being beneficial to improving the product yield of the cylindrical battery cell 30.

[0136] Therefore, after systematic analysis and long-term practice, the inventors found that setting 30μm ≤ e ≤ 60μm is beneficial to improving the energy density of the cylindrical battery cell 30 while also being beneficial to reducing the risk of the binding member 40 wrinkling, thereby being beneficial to improving the product yield of the cylindrical battery cell 30.

[0137] In some embodiments, the electrode body 321 has a middle cross-section, and the electrode body 321 is symmetrically arranged with respect to the middle cross-section along the axial direction X of the electrode body 321, and at least one binding member 40 covers the middle cross-section.

[0138] The middle cross-section can be a cross-section perpendicular to the axial direction X of the electrode body 321 and located exactly in the middle of the electrode body 321 along the axial direction X. During the process of the electrode assembly 32 expanding, expansion may initially occur near the middle cross-section. By arranging at least one restraint 40 to cover the middle cross-section, when the electrode assembly 32 just starts to expand, it can be restricted by the restraint 40, which is beneficial for the restraint of the expansion force of the restraint 40 on the cylindrical battery cell 30, reducing the risk of wrinkles caused by the free expansion of the electrode assembly 32 and further improving the reliability of the cylindrical battery cell 30.

[0139] In some embodiments, as Figure 7 shown, the dimension of the restraint 40 along the axial direction X of the electrode body 321 is d, and the dimension of the electrode body 321 along the axial direction X is D, where 0.75 ≤ d / D ≤ 1.

[0140] When the cylindrical battery cell 30 includes one restraint 40, d is the dimension of one restraint 40 along the axial direction X. When the cylindrical battery cell 30 includes multiple restraints 40, d can be the sum of the dimensions of multiple restraints 40 along the axial direction X.

[0141] Optionally, d / D can be 0.75, 0.8, 0.85, 0.9, 0.95, or 1, etc.

[0142] Through systematic analysis and long-term practice, the inventors found that setting 0.75 ≤ d / D ≤ 1 is beneficial for improving the consistency of the restraint force of the restraint 40 on the electrode assembly 32, and thus beneficial for improving the consistency and stability of the performance of the electrode assembly 32.

[0143] In some embodiments, as Figure 7 shown, the number of restraints 40 is one.

[0144] When the number of restraints 40 is one, a step is formed between the restraint 40 and the surface of the electrode body 321. When the restraint 40 is installed in the housing 311 together with the electrode assembly 32, it is beneficial for reducing the risk of abrasion between the restraint 40 and the housing 311, and thus beneficial for improving the product yield of the cylindrical battery cell 30.

[0145] In some embodiments, as Figure 8 shown, the number of restraints 40 is multiple, and the multiple restraints 40 are arranged at intervals along the axial direction X of the electrode body 321.

[0146] The lengths of different restraint members 40 along the circumferential direction Y may be equal or unequal. The plurality of restraint members 40 are arranged at intervals along the axial direction X of the electrode body 321. During the expansion of the electrode body 321, the space along the axial direction X between two adjacent restraint members 40 can provide space for the expansion of the electrode assembly 32, and the positions of the restraint members 40 and their corresponding central angles can be reasonably set according to the specific position during the expansion of the electrode assembly 32, which is beneficial to further improving the reliable performance of the cylindrical battery cell 30.

[0147] In some embodiments, the material of the outer shell 31 includes carbon steel or stainless steel.

[0148] In the cylindrical battery cell 30, the outer shell 31 may serve as an overcurrent component of the cylindrical battery cell 30. At this time, the current of the cylindrical battery cell 30 will flow through the outer shell 31, and the outer shell 31 will be charged. Even if the outer shell 31 does not serve as an overcurrent component of the cylindrical battery cell 30, the charge in the electrode body 321 may also flow to the outer shell 31 through the gap between the first end 40a and the second end 40b of the restraint member 40, causing the housing 311 to be charged. When the outer shell 31 is charged, the outer shell 31 needs to have good corrosion resistance.

[0149] Both carbon steel and stainless steel have good corrosion resistance. Setting the material of the outer shell 31 to include carbon steel and stainless steel is beneficial to improving the corrosion resistance of the outer shell 31.

[0150] In some embodiments, the restraint member 40 is made of an insulating material.

[0151] Setting the restraint member 40 to be made of an insulating material is beneficial to reducing the risk of internal short circuit of the cylindrical battery cell 30 caused by the contact between the restraint member 40 and the electrode assembly 32, and is also beneficial to reducing the risk of corrosion of the restraint member 40.

[0152] In some embodiments, as Figure 8 、 Figure 9 、 Figure 10 and Figure 11 shown, the electrode assembly 32 includes a first pole piece 323. The first pole piece 323 includes a first active material layer 3231 and a tab 322. The first active material layer 3231 includes a matrix region 3231a and a thinned region 3231b. The thickness of the thinned region 3231b is less than the thickness of the matrix region 3231a and is located on the side of the matrix region 3231a close to the tab 322. The electrode assembly 32 includes a first portion 3211 and a second portion 3212 distributed along its own axial direction X. The first portion 3211 includes the thinned region 3231b, and the second portion 3212 includes the matrix region 3231a. The outer diameter of the first portion 3211 is smaller than the outer diameter of the second portion 3212.

[0153] Optionally, the first pole piece 323 can be a positive pole piece, or the first pole piece 323 can be a negative pole piece. Therefore, either one or both of the positive pole piece and the negative pole piece can be provided with a substrate region 3231a and a thinned region 3231b.

[0154] By reducing the thickness of the thinned region 3231b relative to the substrate region 3231a, during the cold pressing process of the first pole piece 323, the stress concentration at the edge of the thinned region 3231b away from the substrate region 3231a, that is, at the end of the electrode body 321 along the axial direction X, can be reduced, and the risk of fracture of the first pole piece 323 can be reduced.

[0155] Optionally, the surface of the thinned region 3231b can be a flat surface or an arc surface, etc. The thicknesses at various positions inside the thinned region 3231b can be equal or unequal, and can be set according to actual needs.

[0156] It can be understood that since the thickness of the thinned region 3231b is less than the thickness of the substrate region 3231a, after the electrode assembly 32 is wound, the outer diameter of the first part 3211 will be smaller than the outer diameter of the second part 3212.

[0157] In some embodiments, as Figure 9 and Figure 11 shown, the cylindrical battery cell 30 further includes an insulating member 50. The insulating member 50 is wound around the periphery of the tab 322. Along the radial direction of the electrode body 321, the insulating member 50 and the binding member 40 have an overlapping portion, and the overlapping portion is arranged corresponding to the first part 3211.

[0158] The insulating member 50 is wound around the periphery of the tab 322. The insulating member 50 can be in close contact with the tab 322, or the insulating member 50 can be spaced apart from the tab 322. The insulating member 50 can provide a certain insulating property for the tab 322 and the outer shell 31.

[0159] The insulating member 50 is arranged on the outer peripheral side of the first part 3211, and the insulating member 50 can be in close contact with the peripheral surface of the first part 3211. The insulating member 50 can cover the entire region of the first part 3211 along the axial direction X, or the insulating member 50 can cover a partial region of the first part 3211 along the axial direction X.

[0160] Optionally, when the insulating member 50 and the binding member 40 have an overlapping portion at the first part 3211, the binding member 40 can be arranged between the insulating member 50 and the first part 3211, or the insulating member 50 can be arranged between the first part 3211 and the binding member 40. That is to say, the insulating member 50 can be arranged on the outermost side, or the binding member 40 can be arranged on the outermost side.

[0161] Along the radial direction of the electrode body 321, there is an overlapping portion between the insulating member 50 and the binding member 40. Then, along the axial direction X of the electrode assembly 32, the binding member 40 can wrap the electrode body 321 more, which is beneficial to improving the binding effect of the binding member 40 on the electrode body 321. Since the outer diameter of the first part 3211 is smaller than that of the second part 3212, setting the overlapping portion between the binding member 40 and the insulating member 50 along the radial direction corresponding to the first part 3211 is beneficial to reducing the space occupied by the overlapping portion between the insulating member 50 and the binding member 40 along the radial direction inside the outer shell 31, which is beneficial to improving the space utilization rate inside the outer shell 31, and further beneficial to improving the energy density of the cylindrical battery cell 30.

[0162] In some embodiments, as Figure 11 shown, along the radial direction of the electrode body 321, the distance between the outer surface of the overlapping portion and the outer shell 31 is greater than the distance between the outer surface of the corresponding portion of the binding member 40 and the second part 3212 and the outer shell 31.

[0163] During the process of installing the electrode assembly 32 into the housing 311, the second part 3212 can enter the housing before the first part 3211. In the embodiment where the overlapping portion between the insulating member 50 and the binding member 40 corresponds to the first part 3211, the distance between the outer surface of the overlapping portion along the radial direction of the electrode body 321 and the outer shell is greater than the distance between the outer surface of the corresponding portion of the binding member 40 and the second part 3212 along the radial direction of the electrode body 321 and the outer shell 31. During the process of installing the electrode assembly 32 into the housing 311, it is beneficial to reduce the risk of rubbing between the overlapping portion and the housing 311, and beneficial to improving the product yield of the cylindrical battery cell 30.

[0164] In some embodiments, as Figure 11 shown, the outer diameter of the first part 3211 is d1, the outer diameter of the second part 3212 is d2, and the thickness of the insulating member 50 is t1, and d1 + 2t1 ≤ d2.

[0165] Since the maximum outer diameter of the overlapping portion between the insulating member 50 and the binding member 40 can be d1 + 2t1 + 2t2, and the maximum outer diameter of the binding member 40 corresponding to the second part 3212 can be d2 + 2t2, and d1 + 2t1 + 2t2 ≤ d2 + 2t2, that is, d1 + 2t1 ≤ d2.

[0166] During the process of installing the electrode assembly 32 into the housing 311, the second part 3212 can enter the housing before the first part 3211. In the case where there is an overlapping portion between the insulating member 50 and the binding member 40 at the first part 3211, setting d1 + 2t1 ≤ d2 is beneficial to reducing the risk of rubbing between the overlapping portion and the housing 311 during the process of installing the electrode assembly 32 into the housing 311, and beneficial to improving the product yield of the cylindrical battery cell 30.

[0167] In a second aspect, the battery 10 provided in the embodiments of the present application includes the cylindrical battery cell 30 provided in any of the above embodiments.

[0168] Since the battery 10 provided in the embodiments of the present application adopts the cylindrical battery cell 30 provided in any of the above embodiments, it has the same technical effects.

[0169] In a third aspect, the electrical device provided in the embodiments of the present application includes the cylindrical battery cell 30 or the battery 10 provided in any of the above embodiments, and the battery 10 is used to provide electrical energy.

[0170] Since the electrical device provided in the embodiments of the present application adopts the cylindrical battery cell 30 or the battery 10 provided in any of the above embodiments, it has the same technical effects, which will not be elaborated herein.

[0171] In some embodiments, such as Figures 4 to 11As shown, the cylindrical battery cell 30 includes a housing 31, an electrode assembly 32, an insulating member 50, and a binding member 40. The electrode assembly 32 is accommodated in the housing 31. The electrode assembly 32 includes an electrode body 321 and a tab 322, and the tab 322 extends from an end of the electrode body 321. The binding member 40 is disposed between the housing 31 and the electrode assembly 32. The binding member 40 is disposed around the outer peripheral side of the electrode body 321 along the circumferential direction Y of the electrode body 321. The circumference of the electrode body 321 along the circumferential direction Y is L, and the length of the binding member 40 along the circumferential direction Y is l, and 330° ≤ 2π * l / L ≤ 360°. The binding member 40 has a first end 40a and a second end 40b disposed along the circumferential direction Y, and the first end 40a and the second end 40b are spaced apart. The binding member 40 is made of an insulating material. The binding member 40 includes an adhesive layer 41 and a base material layer 42. The adhesive layer 41 is located between the base material layer 42 and the electrode body 321 and adhesively connects the base material layer 42 and the electrode body 321. The adhesive layer 41 includes a pressure-sensitive adhesive, and the material of the base material layer 42 includes polyethylene terephthalate. The thickness e of the binding member 40 satisfies: 30 μm ≤ e ≤ 60 μm. The electrode body 321 has a middle cross-section, and the electrode body 321 is symmetrically disposed with respect to the middle cross-section along the axial direction X of the electrode body 321. At least one binding member 40 covers the middle cross-section. The dimension of the binding member 40 along the axial direction X of the electrode body 321 is d, and the dimension of the electrode body 321 along the axial direction X is D, and 0.75 ≤ d / D ≤ 1. The material of the housing 31 includes carbon steel or stainless steel, and the electrode body 321 is cylindrical. The electrode assembly 32 includes a first electrode tab 323. The first electrode tab 323 includes a first active material layer 3231 and a tab 322. The first active material layer 3231 includes a base region 3231a and a thinned region 3231b. The thickness of the thinned region 3231b is less than the thickness of the base region 3231a, and the thinned region 3231b is located on a side of the base region 3231a close to the tab 322. The electrode body 321 includes a first portion 3211 and a second portion 3212 distributed along its own axial direction X. The first portion 3211 includes the thinned region 3231b, and the second portion 3212 includes the base region 3231a. The outer diameter of the first portion 3211 is smaller than the outer diameter of the second portion 3212. The cylindrical battery cell 30 further includes an insulating member 50. The insulating member 50 is wound around the circumferential side of the tab 322. Along the radial direction of the electrode body 321, the insulating member 50 and the binding member 40 have an overlapping portion, and the overlapping portion is disposed corresponding to the first portion 3211. Along the radial direction of the electrode body 321, the distance between the outer surface of the overlapping portion and the housing 31 is greater than the distance between the outer surface of the corresponding portion of the binding member 40 and the second portion 3212 and the housing 31. The outer diameter of the first portion 3211 is d1, the outer diameter of the second portion 3212 is d2, and the thickness of the insulating member 50 is t1, and d1 + 2t1 ≤ d2.

[0172] For the cylindrical battery cell 30 provided by the embodiment of the present application, by setting 330°≤2π*l / L≤360°, and the binding member 40 has a first end 40a and a second end 40b arranged along the circumferential direction Y, and the first end 40a and the second end 40b are arranged at intervals, which is beneficial to reducing the risk of damage to the electrode assembly 32 due to excessive binding force of the binding member 40 during the expansion process, and during the process of inserting the electrode assembly 32 into the housing, reducing the risk of the structures such as the separator on the surface of the electrode assembly 32 between the first end 40a and the second end 40b of the electrode assembly 32 being scratched by the housing 311, which is beneficial to improving the reliable performance of the cylindrical battery cell 30.

[0173] Although the present application has been described with reference to the preferred embodiments, various improvements can be made to it and components therein can be replaced with equivalents without departing from the scope of the present application. In particular, as long as there is no structural conflict, the technical features mentioned in each embodiment can be combined in any way. The present application is not limited to the specific embodiments disclosed in the text, but includes all technical solutions falling within the scope of the claims.

Claims

1. A cylindrical battery cell, characterized in that, Comprising: A housing; An electrode assembly accommodated in the housing, the electrode assembly including an electrode body and a tab, the tab being led out from an end of the electrode body; the electrode assembly includes a first electrode tab, the first electrode tab including a first active material layer and the tab, the first active material layer including a matrix region and a thinned region, the thickness of the thinned region being less than the thickness of the matrix region and located on a side of the matrix region close to the tab; the electrode body includes a first part and a second part distributed along its own axial direction, the first part including the thinned region, the second part including the matrix region, and the outer diameter of the first part being smaller than the outer diameter of the second part; A binding member provided between the housing and the electrode assembly, the binding member being disposed around the outer peripheral side of the electrode body along the circumferential direction of the electrode body, the binding member having a first end and a second end disposed along the circumferential direction, and the first end and the second end being spaced apart; An insulating member wound around the circumferential side of the tab, and along the radial direction of the electrode body, the insulating member and the binding member having an overlapping portion, and the overlapping portion being correspondingly disposed with the first part; Along the radial direction of the electrode body, the distance between the outer surface of the overlapping portion and the housing is greater than the distance between the outer surface of the portion of the binding member corresponding to the second part and the housing.

2. The cylindrical battery cell according to claim 1, characterized in that, The circumference of the electrode body along the circumferential direction is L , and the length of the binding member along the circumferential direction is l , 300° ≤ 2π * l / L ≤ 360°.

3. The cylindrical battery cell according to claim 1, characterized in that The binding member includes an adhesive layer and a substrate layer, the adhesive layer being located between the substrate layer and the electrode body and adhesively connecting the substrate layer and the electrode body.

4. The cylindrical battery cell according to claim 1, characterized in that, The thickness e of the binding member satisfies: 30μm ≤ e ≤ 60μm.

5. The cylindrical battery cell according to claim 1, wherein, The electrode body has a mid-section, the electrode body is symmetrically disposed with respect to the mid-section along the axial direction of the electrode body, and at least one of the binding members covers the mid-section.

6. The cylindrical battery cell according to claim 1, wherein, The dimension of the binding member along the axial direction of the electrode body is d, and the dimension of the electrode body along the axial direction is D, 0.75 ≤ d / D ≤ 1.

7. The cylindrical battery cell according to claim 1, wherein, The number of the binding members is one.

8. The cylindrical battery cell according to claim 1, wherein, The number of the binding members is multiple, and the multiple binding members are spaced apart along the axial direction of the electrode body.

9. The cylindrical battery cell according to claim 1, wherein The binding member is made of an insulating material.

10. The cylindrical battery cell according to claim 1, wherein The outer diameter of the first part is d1, the outer diameter of the second part is d2, and the thickness of the insulating member is t1, d1 + 2t1 ≤ d2.

11. A battery, characterized in that, Including the cylindrical battery cell according to any one of claims 1 to 10.

12. An electrical device, characterized in that, Including the cylindrical battery cell according to any one of claims 1 to 10, or the battery according to claim 11, the battery being used to provide electrical energy.

Images