Battery monomer, battery device and electric equipment

Abstract

The utility model relates to a battery monomer, a battery device and electric equipment, the battery monomer comprises a shell, an electrode assembly and an insulating layer, and the shell is provided with an accommodating cavity; the electrode assembly is at least partially located in the accommodating cavity, the electrode assembly comprises an electrode main body and a tab led out from the electrode main body along a first direction, the tab comprises a first part and a second part, and the first part is located between the second part and the electrode main body; the insulating layer is arranged on at least one side of the tab in the thickness direction, and the insulating layer covers the first part; wherein the tab is provided with a first reinforcing part, the first reinforcing part extends towards the electrode main body from the second part, and the first reinforcing part comprises a first subsection positioned on the first part and a second subsection positioned on the second part. According to the embodiment of the invention, the reliability of the battery monomer is improved.

Description

Technical Field

[0001] This application relates to the field of battery technology, and in particular to battery cells, battery devices and electrical equipment. Background Technology

[0002] Batteries are widely used in electronic devices such as mobile phones, laptops, electric vehicles, electric cars, electric airplanes, electric ships, electric toy cars, electric toy ships, electric toy airplanes, and power tools. Individual battery cells can include nickel-cadmium batteries, nickel-metal hydride batteries, lithium-ion batteries, and rechargeable alkaline zinc-manganese batteries.

[0003] In the development of batteries, how to improve the reliability of individual battery cells is a technical problem that urgently needs to be solved. Utility Model Content

[0004] In view of the above problems, this application provides a battery cell, a battery device, and an electrical device that can improve the reliability of the battery cell.

[0005] In a first aspect, this application proposes a battery cell including a casing, an electrode assembly, and an insulating layer. The casing has a receiving cavity. The electrode assembly is at least partially located within the receiving cavity. The electrode assembly includes an electrode body and a tab extending from the electrode body along a first direction. The tab includes a first portion and a second portion, with the first portion located between the second portion and the electrode body. An insulating layer is disposed on at least one side of the tab in the thickness direction and covers the first portion. The tab has a first reinforcing portion extending from the second portion toward the electrode body. The first reinforcing portion includes a first segment located in the first portion and a second segment located in the second portion.

[0006] In the embodiments of this application, the battery cell includes a casing, an electrode assembly, and an insulating layer. An insulating layer is provided at the first portion of the tab to provide protection and support. A first reinforcing portion is not only provided at the second portion of the tab but also extends to the first portion. Since a second segment is provided at the second portion of the tab, wrinkles exist in the second portion. By providing the first segment, the wrinkles can be extended to the first portion covered by the insulating layer, reducing the difference in extension between the first and second portions of the tab, thereby reducing the stress difference between the first and second portions of the tab, thus reducing the risk of crescent-shaped marks and pinholes on the tab, and ultimately improving the reliability of the battery cell.

[0007] In some embodiments, there are multiple first segments, which are spaced apart along a second direction; there are multiple second segments, which are spaced apart along a second direction, wherein the first and second directions intersect.

[0008] In these embodiments, the arrangement of multiple first segments and multiple second segments can make the distribution of the first reinforcing part more uniform in the first and second parts of the electrode tab, thereby improving the stability of the electrode tab.

[0009] In some embodiments, each first segment is connected to each second segment in a one-to-one correspondence.

[0010] In these embodiments, the number of the first segment and the second segment are the same, and they are connected in a one-to-one correspondence, which facilitates the simultaneous preparation and molding of the first reinforcing part and the second reinforcing part, and simplifies the molding process.

[0011] In some embodiments, the number of the first segment is greater than the number of the second segment.

[0012] In these embodiments, a greater number of first segments can make the first part of the insulating film and the tab more structurally strong and stable, and less prone to crescent-shaped marks.

[0013] In some embodiments, the spacing between any two adjacent first segments is less than the spacing between any two adjacent second segments; and / or, each first segment and each second segment are offset in a second direction.

[0014] In these embodiments, the high-density and misaligned first segmentation can improve the effect of the electrode ring lunula.

[0015] In some embodiments, the insulating layer is formed with a second reinforcing portion, which at least partially overlaps with the first segment in the thickness direction of the tab.

[0016] In these embodiments, the insulation layer has higher strength after forming the second reinforcement, providing better support for the tab. The second reinforcement also causes the insulation layer to wrinkle, further reducing the stress difference between the first and second parts of the tab and reducing the risk of crescent-shaped marks.

[0017] In some embodiments, the second reinforcing portion extends along the first direction.

[0018] In these embodiments, the second reinforcing portion extends along the first direction, which can make the second reinforcing portion more ductile, which is conducive to the folds extending from the second portion to the first portion and the insulating layer, thereby reducing the stress difference between the first portion and the second portion of the electrode tab.

[0019] In some embodiments, along the first direction, the length of the first portion is H, and the length of the first segment is h, wherein 0.5H≤h≤H.

[0020] In these embodiments, the length h of the first segment is not less than half the length H of the first part, and can also extend through the first part, so that the folds of the second part can be better extended to the first part and the insulating layer.

[0021] In some embodiments, the first segment extends along a first direction, and / or the second segment extends along the first direction.

[0022] In these embodiments, the first segment and the second segment extend along the first direction, which can make the reinforcing part have good ductility, which is conducive to the folds extending from the second part to the first part, and reduce the stress difference between the first part and the second part of the tab.

[0023] In some embodiments, the insulating layer comprises ceramic; and / or, the hardness of the insulating layer is greater than the hardness of the tab.

[0024] In these embodiments, since the folds extend from the second part to the first part and the insulating layer, and the insulating layer can protect against or transfer the formation of crescent marks on the tab, setting the hardness of the insulating layer to be greater than the hardness of the tab can further reduce the risk of crescent marks forming on the tab and the insulating layer, or even make the crescent marks disappear.

[0025] Secondly, this application provides a battery device comprising a battery cell according to any of the first aspects of the above embodiments.

[0026] Thirdly, this application provides an electrical device that includes a battery cell from any of the first aspects of the above-described embodiments; or includes a battery device from the second aspect of the above-described embodiments, wherein the battery device is used to provide electrical energy.

[0027] 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

[0028] The features, advantages, and technical effects of exemplary embodiments of this application will now be described with reference to the accompanying drawings.

[0029] Figure 1 This is a schematic diagram of the structure of a vehicle provided in one embodiment of this application;

[0030] Figure 2 This is a schematic diagram of the structure of a battery device provided in an embodiment of this application;

[0031] Figure 3 This is a schematic diagram of the structure of a battery module provided in one embodiment of this application;

[0032] Figure 4 This is a schematic diagram of the exploded structure of a single battery cell provided in an embodiment of this application;

[0033] Figure 5This is a schematic diagram of the electrode assembly in a battery cell in a flattened state according to an embodiment of this application;

[0034] Figure 6 This is one of the structural schematic diagrams of the tabs and insulating layer in a battery cell provided in an embodiment of this application;

[0035] Figure 7 This is a second schematic diagram of the structure of the tabs and insulating layer in a battery cell provided in an embodiment of this application;

[0036] Figure 8 This is the third schematic diagram of the structure of the tabs and insulating layer in a battery cell provided in an embodiment of this application;

[0037] Figure 9 This is the fourth schematic diagram of the structure of the tabs and insulating layer in a battery cell provided in one embodiment of this application;

[0038] Figure 10 yes Figure 9 One of the schematic diagrams of the cross-sectional structure at point AA in the middle;

[0039] Figure 11 yes Figure 9 Schematic diagram of the cross-sectional structure at point AA (Part 2);

[0040] Figure 12 This is the fifth schematic diagram of the structure of the tabs and insulating layer in a battery cell provided in an embodiment of this application;

[0041] Figure 13 This is the sixth schematic diagram of the structure of the tabs and insulating layer in a battery cell provided in an embodiment of this application;

[0042] Figure 14 This is the seventh schematic diagram of the structure of the tabs and insulating layer in a battery cell provided in an embodiment of this application;

[0043] Figure 15 This is the eighth schematic diagram of the structure of the tabs and insulating layer in a battery cell provided in an embodiment of this application.

[0044] The accompanying drawings may not be drawn to scale.

[0045] Explanation of reference numerals in the attached figures:

[0046] 1000, vehicles;

[0047] 100. Battery assembly; 110. Controller; 120. Motor;

[0048] 200. Battery module;

[0049] 300. Enclosure; 301. First enclosure; 302. Second enclosure;

[0050] 10. Battery cells;

[0051] 1. Outer shell; 11. Housing; 111. Opening; 112. Receiving cavity; 12. End cap;

[0052] 3. Electrode assembly; 31. Electrode body; 32. Tab; 321. First part; 322. Second part;

[0053] 4. Insulation layer;

[0054] 51. First reinforcing section; 511. First segment; 512. Second segment; 52. Second reinforcing section;

[0055] X represents the first direction; Y represents the second direction. Detailed Implementation

[0056] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0057] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used in the description of this application is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms "comprising" and "having," and any variations thereof, in the description, claims, and accompanying drawings of this application are intended to cover non-exclusive inclusion. The terms "first," "second," etc., in the description, claims, or accompanying drawings of this application are used to distinguish different objects, not to describe a specific order or hierarchy.

[0058] In this application, the reference to "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment that is mutually exclusive with other embodiments.

[0059] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "attachment" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0060] In 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 cases: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, in this application, the character " / " generally indicates that the preceding and following related objects have an "or" relationship.

[0061] In the embodiments of this application, the same reference numerals denote the same components, and for the sake of brevity, detailed descriptions of the same components are omitted in different embodiments. It should be understood that the thickness, length, width, and other dimensions of various components in the embodiments of this application shown in the accompanying drawings, as well as the overall thickness, length, width, and other dimensions of the integrated device, are merely illustrative and should not constitute any limitation on this application.

[0062] In this application, "multiple" means two or more (including two).

[0063] Currently, judging from market trends, the application of battery devices is becoming increasingly widespread. Battery devices are not only used in energy storage power systems such as hydropower, thermal power, wind power, and solar power plants, but also widely applied in electric vehicles such as electric bicycles, electric motorcycles, and electric cars, as well as in military equipment and aerospace, among other fields.

[0064] In the preparation of electrodes (positive or negative electrodes), cutting (e.g., electrode slitting or tab die-cutting) is usually required to form the desired size and shape. An insulating coating is applied to the base of the tab. Adding reinforcing ribs to the exposed portion of the tab (i.e., the uncoated portion) can improve the structural strength of the tab and reduce its folding ratio. However, designs such as thin coatings and wide tabs are prone to cold-pressing stretch marks. During electrode winding, repeated rolling and cold-pressing stretch marks further evolve into crescent-shaped marks. These crescent-shaped marks, after being rolled, produce pinholes, thus affecting the battery's reliability and overall performance.

[0065] The above statements are for the purpose of providing background information in relation to this application only and do not necessarily constitute prior art.

[0066] The battery cell provided in this application includes a casing, an electrode assembly, and an insulating layer. An insulating layer is provided at the first part of the electrode tab to provide protection and support for the electrode tab. The first reinforcing part is not only provided at the second part of the electrode tab, but also extends to the first part of the electrode tab to reduce the stress difference between the first part and the second part of the electrode tab, thereby reducing the risk of crescent marks and pinholes on the electrode tab, and thus improving the reliability of the battery cell.

[0067] The technical solutions described in this application are applicable to battery devices and electrical equipment using battery devices. The battery cell can be used, but is not limited to, in battery devices, and can also be used in products such as vehicles, aircraft, ships, electronic equipment, and power tools, thereby improving the reliability of these products.

[0068] Electrical equipment can include vehicles, mobile phones, portable devices, laptops, ships, spacecraft, electric toys, and power tools, etc. Vehicles can be gasoline-powered cars, natural gas-powered cars, or new energy vehicles; new energy vehicles can be pure electric vehicles, hybrid electric vehicles, or range-extended electric vehicles, etc. Spacecraft include airplanes, rockets, space shuttles, and spacecraft, etc. Electric toys include stationary or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys, etc. Power tools include metal cutting power tools, grinding power tools, assembly power tools, and railway power tools, such as electric drills, electric grinders, electric wrenches, electric screwdrivers, electric hammers, impact drills, concrete vibrators, and electric planers, etc. This application does not impose any special limitations on the above-mentioned electrical equipment.

[0069] It should be understood that the technical solutions described in the embodiments of this application are not limited to the battery devices and electrical equipment described above, but can also be applied to all battery devices including housings and electrical equipment using battery devices. However, for the sake of brevity, the following embodiments are all illustrated using electric vehicles as examples.

[0070] Please refer to Figure 1 , Figure 1 The diagram shows the structural features of a vehicle provided in some embodiments of this application.

[0071] Vehicle 1000 can be a gasoline-powered vehicle, a natural gas-powered vehicle, or a new energy vehicle. New energy vehicles can be pure electric vehicles, hybrid electric vehicles, or range-extended electric vehicles, etc. A battery device 100 is installed inside vehicle 1000, which can be located at the bottom, front, or rear of vehicle 1000. The battery device 100 can be used to power vehicle 1000; for example, it can serve as the operating power source for vehicle 1000. Vehicle 1000 may also include a controller 110 and a motor 120. The controller 110 controls the battery to supply power to the motor 120, for example, to meet the power needs of vehicle 1000 during starting, navigation, and driving.

[0072] In some embodiments of this application, 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.

[0073] Figure 2 A schematic diagram of the structure of a battery device according to an embodiment of this application is shown.

[0074] The battery device 100 mentioned in the embodiments of this application may include one or more battery cell assemblies for providing voltage and capacity. A battery cell assembly may include multiple battery cells 10, which are connected in series, parallel, or mixed connections via a busbar.

[0075] In this embodiment of the application, the battery cell 10 can be a secondary battery, which refers to the battery cell 10 that can be used again after being discharged by recharging to activate the active material.

[0076] The battery cell 10 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., and this application embodiment is not limited to this. The battery cell 10 can be cylindrical, flat, cuboid, or other shapes, and this application embodiment is not limited to this either.

[0077] The battery cell 10 includes an electrode assembly 3 and an electrolyte. The electrode assembly 3 includes a positive electrode, a negative electrode, and a separator. The battery cell 10 mainly operates by the movement of metal ions between the positive and negative electrode. The positive electrode includes a positive current collector and a positive active material layer, with the positive active material layer coated on the surface of the positive current collector. The positive current collector includes a positive current collection section and a positive electrode tab connected to the positive current collection section. The positive current collection section is coated with the positive active material layer, while the positive electrode tab is not coated with the positive active material layer. Taking a lithium-ion battery as an example, the material of the positive current collector can be aluminum, and the positive active material layer includes positive active material, which can be lithium cobalt oxide, lithium iron phosphate, ternary lithium, or lithium manganese oxide, etc. The negative electrode sheet includes a negative current collector and a negative active material layer, the negative active material layer being coated on the surface of the negative current collector. The negative current collector includes a negative current collection section and a negative electrode tab connected to the negative current collection section. The negative current collection section is coated with the negative active material layer, while the negative electrode tab is not coated with the negative active material layer. The material of the negative current collector can be copper, and the negative active material layer includes negative active material, which can be carbon or silicon, etc. The material of the separator can be PP (polypropylene) or PE (polyethylene), etc.

[0078] In some embodiments, the battery cell assembly is typically formed by arranging a plurality of battery cells 10.

[0079] As an example, the battery cell assembly can be a battery module 200, which is formed by arranging and fixing multiple battery cells 10 into a single module. As an example, the battery module 200 can be formed by bundling multiple battery cells 10 together with cable ties.

[0080] The battery device 100 mentioned in the embodiments of this application refers to a single physical module comprising one or more battery cells 10 to provide higher voltage and capacity. For example, the battery device 100 mentioned in this application may include a battery module 200 or a battery pack. A battery pack generally includes a housing 300 for encapsulating one or more battery cells 10. The housing 300 can prevent liquids or other foreign objects from affecting the charging or discharging of the battery cells 10.

[0081] In some embodiments, the battery device 100 may be a battery pack, which includes a housing 300 and one or more battery cell assemblies housed in the housing 300.

[0082] As an example, the battery cell assembly can be a battery module 200, which can be housed in the housing 300 by fixing the battery module 200 in the housing 300.

[0083] As an example, the battery cell assembly can also be housed in the housing 300 by directly fixing multiple battery cells 10 to the housing 300.

[0084] As an example, the housing 300 may include a first housing 301 and a second housing 302. The first housing 301 and the second housing 302 cover each other, and together they define a closed receiving space for accommodating the battery cell assembly. Here, "closed" means covered or closed, and can be sealed or unsealed. The first housing 301 may be a top cover or a bottom plate.

[0085] The second box 302 can be a hollow structure with one end open, and the first box 301 is a plate-like structure. The first box 301 covers the open side of the second box 302 to form a box 300 with a receiving portion. Alternatively, both the first box 301 and the second box 302 can be hollow structures with one side open, and the open side of the first box 301 covers the open side of the second box 302 to form a box 300 with a receiving space. Of course, the first box 301 and the second box 302 can be of various shapes, such as cylinders, cuboids, etc.

[0086] As an example, the housing 300 may include a top cover, a frame, and a bottom plate. The top cover and the bottom plate are respectively connected to the frame, so that the interior of the housing 300 forms an enclosed space to accommodate the battery cell assembly.

[0087] In some embodiments, the housing 300 may be part of the chassis structure of the vehicle 1000. For example, a portion of the housing 300 may be at least a portion of the floor of the vehicle 1000, or a portion of the housing 300 may be at least a portion of the crossbeams and longitudinal beams of the vehicle 1000.

[0088] In some embodiments, the battery device 100 may be an energy storage device.

[0089] Energy storage devices can be used in energy storage power stations, wind power generation systems, solar power generation systems, mobile power systems, or temporary power supply systems. Energy storage devices can store electrical energy as needed and output it when appropriate. For example, energy storage devices can store electrical energy during off-peak hours and provide power to relevant users or electrical equipment during peak hours.

[0090] In some embodiments, the energy storage device includes an energy storage container, an energy storage cabinet, etc.

[0091] Figure 3 A schematic diagram of the structure of a battery module according to an embodiment of this application is shown.

[0092] In some embodiments, such as Figure 2 and Figure 3 As shown, there are multiple battery cells 10. These multiple battery cells 10 are first connected in series, parallel, or in a mixed manner to form a battery module 200. The multiple battery modules 200 are then connected in series, parallel, or in a mixed manner to form a whole, which is housed in the casing 300.

[0093] Multiple battery cells 10 in the battery module 200 can be electrically connected through a busbar component to achieve parallel, series, or mixed connection of multiple battery cells 10 in the battery module 200.

[0094] Figure 4 An exploded structural diagram of a battery cell according to an embodiment of this application is shown.

[0095] This application provides a battery cell 10, which includes a housing 1 and an electrode assembly 3 housed within the housing 1.

[0096] In some embodiments, the outer casing 1 may be a steel casing, an aluminum casing, or a composite metal casing (such as a copper-aluminum composite casing 1), etc.

[0097] The outer shell 1 may be a hollow structure, with an internal cavity 112 for accommodating the electrode assembly 3 and the electrolyte.

[0098] In some embodiments, the outer casing 1 of the battery cell 10 is a cylindrical casing 1, a square casing 1, a prismatic casing 1, or a casing 1 of other shapes.

[0099] In some embodiments, the housing 1 includes a housing 11 and an end cap 12. The housing 11 has an opening 111, and the end cap 12 is connected to the housing 11 and covers the opening 111. The housing 11 is a component for engaging with the end cap 12 to form an internal cavity of the battery cell 10. The formed internal cavity can be used to accommodate the electrode assembly 3, the electrolyte, and other components.

[0100] The housing 11 and the end cap 12 can be separate components. For example, an opening 111 can be provided on the housing 11, and the end cap 12 can be used to close the opening 111 to form an internal cavity of the battery cell 10.

[0101] The housing 11 can be of various shapes and sizes, such as cuboid or cylindrical. Specifically, the shape of the housing 11 can be determined according to the specific shape and size of the electrode assembly 3. The housing 11 can be made of various materials, such as copper, iron, aluminum, stainless steel, aluminum alloy, etc.

[0102] The shape of the end cap 12 can be adapted to the shape of the housing 11 to fit the housing 11. The material of the end cap 12 can be the same as or different from the material of the housing 11. Optionally, the end cap 12 can be made of a material with a certain hardness and strength (such as copper, iron, aluminum, stainless steel, aluminum alloy, etc.), so that the end cap 12 is not easily deformed when subjected to compression and impact, so that the battery cell 10 can have higher structural strength and improve reliability.

[0103] The end cap 12 is connected to the housing 11 by welding, bonding, snap-fitting or other means.

[0104] The housing 11 may have an opening 111 at one end or at both ends. In some examples, the housing 11 may have an opening 111 on one side, with one end cap 12 covering the housing 11. In other examples, the housing 11 may have an opening 111 on both sides, with two end caps 12 covering the two openings 111 of the housing 11 respectively.

[0105] Electrode assembly 3 is the component in the battery cell 10 where the electrochemical reaction takes place. The housing 11 may contain one or more electrode assemblies 3.

[0106] In some embodiments, the electrode assembly 3 includes a positive electrode, a negative electrode, and a separator, wherein the positive electrode and the negative electrode have opposite polarities, and the separator separates the positive electrode and the negative electrode.

[0107] At least a portion of the separator is located between the positive and negative electrode plates. During the charging and discharging process of the battery cell 10, active ions (e.g., lithium ions) repeatedly insert and extract between the positive and negative electrode plates. The separator, positioned between the positive and negative electrode plates, serves to prevent short circuits between the positive and negative electrodes while allowing active ions to pass through.

[0108] In some embodiments, the positive electrode may include a positive current collector and a positive electrode film layer disposed on at least one surface of the positive current collector.

[0109] As an example, the positive current collector has two surfaces opposite each other in thickness, and the positive electrode film layer is disposed on either or both of the opposite surfaces of the positive current collector.

[0110] As an example, the positive current collector can be a metal foil, a conductive polymer material, a carbon material, or a composite current collector. For example, as a metal foil, pure metals, alloys, or surface-treated metals can be used, including but not limited to stainless steel, copper, aluminum, nickel, nickel alloys, titanium, or silver. The composite current collector may include a polymer material base layer and a metal layer. The composite current collector can be formed by forming a metal material (aluminum, aluminum alloys, nickel, nickel alloys, titanium, titanium alloys, silver, and silver alloys, etc.) on a polymer material substrate (such as a substrate of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0111] As an example, the positive electrode film layer includes a positive electrode active material, which may include at least one of the following materials: lithium phosphate, lithium transition metal oxide, and their respective modified compounds. However, this application is not limited to these materials, and other conventional materials that can be used as positive electrode active materials for batteries may also be used. These positive electrode active materials may be used alone or in combination of two or more. Examples of lithium phosphate include, but are not limited to, at least one of lithium iron phosphate (such as LiFePO4 (also referred to as LFP)), lithium iron phosphate and carbon composites, lithium manganese phosphate (such as LiMnPO4), lithium manganese phosphate and carbon composites, lithium iron manganese phosphate, and lithium iron manganese phosphate and carbon composites. Examples of lithium transition metal oxides include, but are not limited to, lithium cobalt oxide (such as LiCoO2), lithium nickel oxide (such as LiNiO2), lithium manganese oxide (such as LiMnO2, LiMn2O4), lithium nickel cobalt oxide, lithium manganese cobalt oxide, lithium nickel manganese oxide, and lithium nickel cobalt manganese oxide (such as LiNi). 1 / 3 Co 1 / 3 Mn 1 / 3 O2 (also known as NCM) 333 LiNi 0.5 Co 0.2 Mn 0.3 O2 (also known as NCM) 523LiNi 0.5 Co 0.25 Mn 0.25 O2 (also known as NCM) 211 LiNi 0.6 Co 0.2 Mn 0.2 O2 (also known as NCM) 622 LiNi 0.8 Co 0.1 Mn 0.1 O2 (also known as NCM) 811 ), lithium nickel cobalt aluminum oxide (such as LiNi) 0.8 Co 0.15 Al 0.05 At least one of O2 and its modified compounds. Modified compounds refer to substances obtained by modification methods such as doping or coating based on the above-mentioned substances.

[0112] In some embodiments, the negative electrode may include a negative current collector.

[0113] As an example, the negative electrode current collector can be a metal foil, a conductive polymer material, a carbon material, or a composite current collector. For example, as a metal foil, pure metals, alloys, or surface-treated metals can be used, including but not limited to stainless steel, copper, aluminum, nickel, nickel alloys, titanium, or silver. The composite current collector may include a polymer material substrate and a metal layer. The composite current collector can be formed by forming a metal material (copper, copper alloys, nickel, nickel alloys, titanium, titanium alloys, silver, and silver alloys, etc.) on a polymer material substrate (such as a substrate of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0114] As an example, the negative electrode sheet may include a negative electrode current collector and a negative electrode film layer disposed on at least one surface of the negative electrode current collector.

[0115] As an example, the negative electrode current collector has two surfaces opposite each other in its own thickness direction, and the negative electrode film layer is disposed on either or both of the two opposite surfaces of the negative electrode current collector.

[0116] As an example, the negative electrode film layer includes a negative electrode active material, which may be a negative electrode active material known in the art for use in battery cell 10. 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. Silicon-based materials may be selected from at least one of elemental silicon, silicon oxide compounds, silicon-carbon composites, silicon-nitrogen composites, and silicon alloys. Tin-based materials may be selected from at least one of elemental tin, tin oxide compounds, and tin alloys. However, this application is not limited to these materials, and other conventional materials that can be used as negative electrode active materials for battery cell 10 may also be used. These negative electrode active materials may be used alone or in combination of two or more.

[0117] In some embodiments, the positive current collector can be made of aluminum, and the negative current collector can be made of copper.

[0118] In some embodiments, the separator includes a separator membrane. The separator membrane in this application can be any known porous membrane with good chemical and mechanical stability.

[0119] As an example, the main material of the separator can be selected from at least one of glass fiber, non-woven fabric, polyethylene, polypropylene, polyvinylidene fluoride, and ceramics. The separator can be a single-layer film or a multi-layer composite film, without particular limitation. When the separator is a multi-layer composite film, the materials of each layer can be the same or different.

[0120] Inorganic particle coating, organic particle coating, or organic / inorganic composite coating can also be applied to the surface of the separator.

[0121] The separator can be a single component located between the positive and negative electrodes, or it can be attached to the surface of the positive or negative electrode.

[0122] In some embodiments, the separator is a solid electrolyte. The solid electrolyte is disposed between the positive and negative electrode plates, serving both to transport ions and to isolate the positive and negative electrodes.

[0123] In some embodiments, the battery cell 10 further includes an electrolyte, which acts as a conductor of ions between the positive and negative electrodes. The electrolyte used in this application can be selected according to requirements. The electrolyte can be liquid, gel, or solid.

[0124] The electrode assembly 3 is mainly formed by winding or stacking electrode sheets. The electrode sheets are divided into positive and negative electrode sheets, and a separator is usually provided between them. The portions of the positive and negative electrode sheets containing active material constitute the electrode body, while the portions without active material each constitute a tab. The positive and negative tabs can be located together at one end of the electrode body or at opposite ends. During the charging and discharging process of the battery cell 10, the positive and negative active materials react with the electrolyte, and the tabs connect to the electrode terminals to form a current loop.

[0125] The electrode assembly 3 can be a wound structure, a stacked structure, or a hybrid structure of wound and stacked.

[0126] In some embodiments, electrode assembly 3 is a wound structure. The positive electrode and negative electrode are wound into a wound structure.

[0127] In some embodiments, the electrode assembly 3 is a stacked structure. As an example, multiple positive and negative electrodes can be provided, with multiple positive and multiple negative electrodes stacked alternately. Multiple spacers can be provided and respectively provided between any adjacent positive or negative electrodes. Alternatively, the spacers can be provided continuously and provided between any adjacent positive or negative electrodes by folding.

[0128] In some embodiments, the electrode assembly 3 may be cylindrical, flat, or polygonal, etc.

[0129] In some embodiments, the electrode assembly 3 is provided with tabs that can conduct current from the electrode assembly 3. The tabs include a positive tab and a negative tab.

[0130] The battery cell 10 may include a housing 11. The housing 11 is an assembly that mates with the end cap 12 to form an internal environment for the battery cell 10, wherein the formed internal environment can accommodate the electrode assembly 3, electrolyte (not shown in the figure), and other components. The housing 11 can be a steel housing, an aluminum housing, a plastic housing (such as polypropylene), a composite metal housing (such as a copper-aluminum composite housing 11), or an aluminum-plastic film, etc. In some embodiments, the housing 11 can be a sealed structure or a non-sealed structure. As an example, when the housing 11 is a non-sealed structure, the housing 11 serves to protect the electrode assembly 3, and a sealing bag is included between the housing 11 and the electrode assembly 3. The sealing bag is used to encapsulate the electrode assembly 3 and the electrolyte. Specifically, the sealing bag can be a bag-shaped insulating component or an aluminum-plastic film. When the housing 11 is a sealed structure, it is used to encapsulate the electrode assembly 3 and electrolyte, etc.

[0131] As an example, the battery cell 10 can be a cylindrical battery cell, a prismatic battery cell, a pouch battery cell, or a battery cell of other shapes. Prismatic battery cells include prismatic battery cells, blade-shaped battery cells, and multi-prismatic batteries, such as hexagonal prismatic batteries. This application does not have any particular limitations.

[0132] The housing 11 and end cap 12 can be independent components. One or more openings 111 can be provided on the housing 11, and one or more end caps 12 can close the openings 111 to form the internal environment of the battery cell 10. Optionally, the end cap 12 and housing 11 can be integrated. Optionally, the end cap 12 and housing 11 can form a common connection surface before other components are inserted into the housing, and the end cap 12 closes the housing 11 when it is necessary to encapsulate the interior of the housing 11.

[0133] In some embodiments, the electrode terminals can be disposed on the end cap 12 or on the housing 11, and the electrode terminals are electrically connected to the electrode tabs. The electrode terminals can be directly connected to the electrode tabs or indirectly connected to the electrode tabs through an adapter.

[0134] Please see Figures 4 to 7 In a first aspect, this application proposes a battery cell 10, which includes a housing 1, an electrode assembly 3, and an insulating layer 4. The housing 1 has a receiving cavity 112. The electrode assembly 3 is at least partially located within the receiving cavity 112. The electrode assembly 3 includes an electrode body 31 and a tab 32 extending from the electrode body 31 along a first direction X. The tab 32 includes a first portion 321 and a second portion 322. The first portion 321 is located between the second portion 322 and the electrode body 31. The insulating layer 4 is disposed on at least one side of the tab 32 in the thickness direction and covers the first portion 321. The tab 32 has a first reinforcing portion 51 extending from the second portion 322 toward the electrode body 31. The first reinforcing portion 51 includes a first segment 511 located in the first portion 321 and a second segment 512 located in the second portion 322.

[0135] In some examples, the housing 1 may contain one or more electrode assemblies 3. Electrode assemblies 2 are components in the battery cell 10 where electrochemical reactions occur.

[0136] The first part 321 is connected between the second part 322 and the electrode body 31. The first part 321 can also be referred to as the root of the electrode tab 32, and the second part 322 can also be referred to as the outer side of the electrode tab 32. An insulating layer 4 can be provided on both sides of the first part 321 of the electrode tab 32. The insulating layer 4 can provide support for the electrode tab 32 on the one hand, and also provide insulation and protection for the electrode tab 32 on the other hand.

[0137] As an example, the insulating layer 4 can be attached to at least one side of the tab 32 in the thickness direction by means of a coating. Optionally, the tab 32 may have an insulating layer 4 on both sides in the thickness direction.

[0138] In some examples, the electrode body 31 can be the electrode body 31 of a positive electrode plate, and the tab 32 can be a positive tab 32. Alternatively, the electrode body 31 can be the electrode body 31 of a negative electrode plate, and the tab 32 can be a negative tab 32.

[0139] The first reinforcing part 51 can be used to improve the overall or partial strength of the electrode tab 32, thereby improving the mechanical strength and stability of the electrode tab 32. Optionally, the first reinforcing part 51 can be a reinforcing rib structure. As an example, the first reinforcing part 51 can be formed by stamping, high-pressure gas extrusion, gear rolling, or other processes on the electrode tab 32. The shape of the reinforcing rib can be strip-shaped, circular, rhomboid, etc., and the shapes can be continuous or spaced out, such as... Figures 8 to 15 As shown. Optionally, the reinforcing ribs can also be a mixture of strip, rhombus, and circular shapes. Optionally, refer to... Figure 9 The rhomboid reinforcing ribs can be further formed within the strip reinforcing ribs. That is, the strip reinforcing ribs are formed in the first process, and then the rhomboid reinforcing ribs are formed in a second reinforcing rib forming process, which can further enhance the strength of the electrode lug 32. Optionally, the shape of the reinforcing ribs can be convex or concave relative to the plane where the electrode lug is located. The convex or concave shapes of adjacent reinforcing ribs can be the same or opposite, such as... Figure 10 and Figure 11 As shown.

[0140] The method of forming the first reinforcing part 51 by compressing gas under high pressure produces no metal shavings, reducing the safety hazard of cell short circuits caused by metal shavings. The tab 32 can be locally reinforced as needed to improve the targeting and effectiveness of the first reinforcing part 51.

[0141] When the first reinforcing part 51 is formed by the gear roller pressing, the electrode tab 32 is placed in the imprinting device. By adjusting the gap of the gear roller and the air pressure, the depth and width of the imprint can be controlled. The imprinting process has good controllability, and the parameters of the first reinforcing part 51 can be adjusted as needed.

[0142] In the embodiment of this application, the battery cell 10 includes a casing 1, an electrode assembly 3, and an insulating layer 4. An insulating layer 4 is provided at the first portion 321 of the tab 32 to provide protection and support for the tab 32. A first reinforcing portion 51 is not only provided at the second portion 322 of the tab 32 but also extends to the first portion 321 of the tab 32. Since a second segment 512 is provided at the second portion 322 of the tab 32, the second portion 322 of the tab 32 has wrinkles. By providing the first segment 511, the wrinkles can be extended to the first portion 321 covered by the insulating layer 4, reducing the difference in extension between the first portion 321 and the second portion 322 of the tab 32, thereby reducing the stress difference between the first portion 321 and the second portion 322 of the tab 32, thus reducing the risk of crescent-shaped marks and pinholes on the tab 32, and further improving the reliability of the battery cell 10.

[0143] In some embodiments, the insulating layer 4 is formed with a second reinforcing portion 52, which at least partially overlaps with the first segment 511 in the thickness direction of the tab 32.

[0144] The second reinforcing part 52 can be formed simultaneously with the first segment 511 of the first reinforcing part 51. For example, the insulating layer 4 is first coated on the first part 321 of the tab 32, and then the insulating layer 4 and the tab 32 as a whole are formed by gear rolling to form the first reinforcing part 51 and the second reinforcing part 52.

[0145] In these embodiments, the insulation layer 4 has higher strength after forming the second reinforcing part 52, and provides better support for the tab 32. The setting of the second reinforcing part 52 also causes the insulation layer 4 to form wrinkles, further reducing the stress difference between the first part 321 and the second part 322 of the tab 32 and reducing the risk of crescent marks.

[0146] Optionally, in the thickness direction of the tab 32, the second reinforcing part 52 coincides with the first segment 511. This arrangement allows the crescent mark originally to be formed on the first part 321 of the tab 32 to be transferred to the insulating layer 4. If the hardness of the insulating layer 4 is high, the risk of forming a crescent mark can be further reduced or even the crescent mark can be eliminated.

[0147] In some embodiments, the insulating layer 4 comprises ceramic.

[0148] Ceramic material can be adhered to the tab 32 via a coating. On one hand, the ceramic coating protects the tab 32 from external environmental damage, such as corrosion and oxidation, thereby improving the stability and lifespan of the tab 32. On the other hand, the ceramic coating optimizes the microstructure of the surface of the first portion 321 of the tab 32, reducing uneven current distribution on the surface of the first portion 321 and enhancing the conductivity of the tab 32. For example, the insulating layer 4 may be made of AT9 or AT11. Ceramic materials also exhibit high hardness after curing.

[0149] In some embodiments, the hardness of the insulating layer 4 is greater than the hardness of the tab 32.

[0150] In these embodiments, since the folds extend from the second portion 322 to the first portion 321 and the insulating layer 4, and the insulating layer 4 can protect against or transfer the formation of crescent marks on the tab 32, setting the hardness of the insulating layer 4 to be greater than the hardness of the tab 32 can further reduce the risk of crescent marks forming on the tab 32 and the insulating layer 4, or even make the crescent marks disappear.

[0151] In the relevant technology, the reinforcing rib is set on the outside of the tab 32. The outside of the tab 32 is relatively soft and has wrinkles, while the insulation layer 4 is relatively hard and has no wrinkles. The stress difference between the two can easily cause crescent marks to appear on the outside of the tab 32 (where there is no insulation layer 4).

[0152] Now, the first reinforcing part 51 is extended to the insulating layer 4. Both parts of the tab 32 have wrinkles and the stress is consistent. The crescent mark that was originally at the junction of the insulating layer 4 and the outer side of the tab 32 has moved inward to the insulating layer 4. Due to the high hardness of the insulating layer 4, the crescent mark disappears. A second reinforcing part 52 is provided on the insulating layer 4, overlapping with the first segment 511, creating wrinkle extension, reducing the difference in extension between the two parts of the tab 32, and reducing the risk of crescent mark formation.

[0153] Reference Figure 6 and Figure 7 In some embodiments, the second reinforcing portion 52 extends along the first direction X.

[0154] The first direction X is the extension direction of the tab 32 extending from the electrode body 31.

[0155] In these embodiments, the second reinforcing portion 52 extends along the first direction X, which can make the second reinforcing portion 52 more ductile, which is conducive to the folds extending from the second portion 322 to the first portion 321 and the insulating layer 4, thereby reducing the stress difference between the first portion 321 and the second portion 322 of the tab 32.

[0156] In some embodiments, there are multiple first segments 511, and the multiple first segments 511 are spaced apart along the second direction Y; there are multiple second segments 512, and the multiple second segments 512 are spaced apart along the second direction Y; wherein the first direction X and the second direction Y intersect.

[0157] As an example, the second direction Y can be perpendicular to the first direction X. The thickness direction of the tab 32 can be perpendicular to both the first direction X and the second direction Y.

[0158] Optional, refer to Figure 6 The first segment 511 and the second segment 512 can both be strip-shaped. The number of the first segment 511 can be 6, and the number of the second segment 512 can also be 6. Optionally, the number of the first segment 511 can be 9, and the number of the second segment 512 can be 6.

[0159] In these embodiments, the arrangement of multiple first segments 511 and multiple second segments 512 can make the distribution of the first reinforcing part 51 more uniform in the first part 321 and the second part 322 of the tab 32, thereby improving the stability of the tab 32.

[0160] In some embodiments, each first segment 511 is connected to each second segment 512 in a one-to-one correspondence.

[0161] In these embodiments, the number of first segments 511 and second segments 512 are the same and they are connected in a one-to-one correspondence, which facilitates the simultaneous preparation and molding of the first reinforcing part 51 and the second reinforcing part 52, and makes the molding process simpler.

[0162] In some embodiments, refer to Figure 7 The number of segments 511 in the first segment is greater than the number of segments 512 in the second segment.

[0163] As an example, the second reinforcing part 52 can overlap with a plurality of first segments 511 in the thickness direction.

[0164] In these embodiments, a greater number of first segments 511 can make the structure of the first portion 321 of the insulating film and the tab 32 stronger and more stable, and less prone to crescent marks.

[0165] In some embodiments, the spacing between any two adjacent first segments 511 is less than the spacing between any two adjacent second segments 512. Optionally, the spacing between any two adjacent first segments 511 is equal. The spacing between any two adjacent second segments 512 may also be equal. In these embodiments, the density of the first segments 511 is greater than the density of the second segments 512.

[0166] In some embodiments, each first segment 511 and each second segment 512 are offset in the second direction Y. Offset in the second direction Y means that the first segment 511 and the second segment 512 are not continuous in the second direction Y.

[0167] In these embodiments, the high-density and misaligned first segment 511 can improve the effect of the tab 32 crescent mark.

[0168] Reference Figure 6 In some embodiments, along the first direction X, the length of the first portion 321 is H, and the length of the first segment 511 is h, wherein 0.5H≤h≤H.

[0169] The length of the first part 321 can refer to the average length of the first part 321, for example, by using calipers to measure the values ​​at ten points where the spacing between each segment is equal and taking the average value. The length of the first segment 511 is calculated similarly.

[0170] In these embodiments, the length h of the first segment 511 is not less than half the length H of the first part 321, and can also extend through the first part 321, so that the folds of the second part 322 can be better extended to the first part 321 and the insulating layer 4.

[0171] In some embodiments, the first segment 511 extends along the first direction X, and optionally, the second segment 512 extends along the first direction X.

[0172] In these embodiments, the first segment 511 and the second segment 512 extend along the first direction X, which can make the reinforcing part have good ductility, which is conducive to the folds extending from the second part 322 to the first part 321, and reduce the stress difference between the first part 321 and the second part 322 of the tab 32.

[0173] It should be noted that the second segment 512 can also extend in other directions. For example, after the second segment 512 is bent, its extension direction is different from the first direction X.

[0174] Reference Figure 14 and Figure 15 The extension directions of the first segment 511 and the second segment 512 can also be set irregularly, and the first segment 511 and the second segment 512 can also be in the shape of "X" or "W".

[0175] Secondly, embodiments of this application provide a battery device 100, including a battery cell 10 of any of the embodiments of the first aspect described above.

[0176] Thirdly, embodiments of this application provide an electrical device including a battery cell 10 from any of the embodiments of the first aspect described above, or a battery device 100 from the embodiments of the second aspect described above. The battery cell 10 or the battery device 100 is used to provide electrical energy to the electrical device.

[0177] The electrical equipment can be any of the aforementioned devices or systems that utilize battery devices 100.

[0178] Please see Figures 4 to 15 According to some embodiments of this application, this application provides a battery cell 10, which includes a housing 1, an electrode assembly 3, and an insulating layer 4. The housing 1 has a receiving cavity 112. The electrode assembly 3 is at least partially located within the receiving cavity 112 and includes an electrode body 31 and a tab 32 extending from the electrode body 31 along a first direction X. The tab 32 includes a first portion 321 and a second portion 322, with the first portion 321 located between the second portion 322 and the electrode body 31. The insulating layer 4 is disposed on at least one side of the tab 32 in the thickness direction and covers the first portion 321. The tab 32 has a first reinforcing portion 51 extending from the second portion 322 toward the electrode body 31. The first reinforcing portion 51 includes a first segment 511 located in the first portion 321 and a second segment 512 located in the second portion 322. The insulating layer 4 has a second reinforcing portion 52, which at least partially overlaps with the first segment 511 in the thickness direction of the tab 32. The insulating layer 4 comprises ceramic. The hardness of the insulating layer 4 is greater than the hardness of the tab 32. Along the first direction X, the length of the first portion 321 is H, and the length of the first segment 511 is h, wherein 0.5H ≤ h ≤ H.

[0179] 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.

Claims

1. A battery cell, characterized by, The battery cell comprises: a housing having a receiving cavity; an electrode assembly at least partially located in the receiving cavity, the electrode assembly comprising an electrode body and a tab led out from the electrode body in a first direction, the tab comprising a first portion and a second portion, the first portion being located between the second portion and the electrode body; an insulating layer provided on at least one side of the tab in a thickness direction, the insulating layer covering the first portion; wherein the tab is formed with a first reinforcing portion, the first reinforcing portion extending from the second portion towards the electrode body, the first reinforcing portion comprising a first segment located at the first portion and a second segment located at the second portion.

2. The battery cell of claim 1, wherein, The number of the first segments is plural, and the plural first segments are arranged in a second direction at intervals; the number of the second segments is plural, and the plural second segments are arranged in the second direction at intervals; wherein the first direction and the second direction intersect.

3. The battery cell of claim 2, wherein, Each of the first segments is connected to each of the second segments in a one-to-one correspondence.

4. The battery cell of claim 2, wherein, The number of the first segments is greater than the number of the second segments.

5. The battery cell of claim 4, wherein, The interval between any two adjacent first segments is less than the interval between any two adjacent second segments; and / or, each of the first segments and each of the second segments are arranged in a staggered manner in the second direction.

6. The battery cell according to any one of claims 1 to 5, characterized in that, The insulating layer is formed with a second reinforcing portion, and in the thickness direction of the tab, the second reinforcing portion at least partially overlaps the first segment.

7. The battery cell of claim 6, wherein, The second reinforcing portion extends in the first direction.

8. The battery cell of any one of claims 1 to 5, wherein, In the first direction, the length of the first portion is H, and the length of the first segment is h, wherein 0.5H≤h≤H.

9. The battery cell of any one of claims 1 to 5, wherein, The first segment extends in the first direction, and / or the second segment extends in the first direction.

10. The battery cell of any one of claims 1 to 5, wherein, The insulating layer comprises ceramic; and / or, the hardness of the insulating layer is greater than the hardness of the tab.

11. A battery device characterized by comprising: The battery device comprises the battery cell as claimed in any one of claims 1 to 10.

12. An electrical device, characterized by The battery device comprises the battery cell as claimed in any one of claims 1 to 10, for providing electric energy; or the battery device as claimed in claim 11, for providing electric energy.

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