Battery monomer, battery cell, battery device and energy storage device

Abstract

The embodiment of the utility model provides a battery monomer, a battery cell, a battery device, an energy storage device, an energy storage system, a power utilization device and a charging network, and belongs to the technical field of batteries. Each battery monomer comprises a shell and a battery cell; the battery cell is arranged in the shell, the battery cell comprises a first pole piece, an isolating membrane and a second pole piece, the first pole piece, the isolating membrane and the second pole piece are stacked and wound, and each of the first pole piece and the second pole piece comprises a flat part and a bent part which are sequentially connected in the winding direction; the bent parts at the two ends of the flat part are oppositely arranged; wherein the outer end of the first pole piece in the winding direction comprises a protection section exceeding the outer end of the second pole piece, and the protection section comprises at least one bending part. The breakage risk of the effective section of the outer ring in the battery cell can be reduced, and the service life of the battery cell is prolonged.

Description

Technical Field

[0001] This application relates to the field of battery technology, and more specifically, to a battery cell, battery assembly, energy storage device, energy storage system, power consumption device, and charging network. Background Technology

[0002] In related technologies, wound-type battery cells have an expansion problem during use. The expansion problem can have a significant impact on the safety of individual battery cells and affect the cycle life of the battery cells. Utility Model Content

[0003] This application provides a battery cell, a battery assembly, an energy storage device, an energy storage system, an electrical device, and a charging network to reduce the risk of breakage of the outer effective section of the battery cell and extend the service life of the battery cell.

[0004] In a first aspect, embodiments of this application provide a battery cell, including: a casing and a battery cell;

[0005] A battery cell is disposed within the housing. The battery cell includes a first electrode, a separator, and a second electrode. The first electrode, the separator, and the second electrode are stacked and wound together. Both the first electrode and the second electrode include a flat portion and a curved portion that are sequentially connected along the winding direction. The curved portions at both ends of the flat portion are disposed opposite to each other.

[0006] The outer end of the first electrode along the winding direction includes a protective section extending beyond the outer end of the second electrode, and the protective section includes at least one bent portion.

[0007] In the above technical solution, by setting a protection section extending beyond the outer end of the first electrode along the winding direction, when the cell expands, the effective section of the first or second electrode located on the outer ring is subject to the binding force of the protection section and the expansion force inside the cell due to the restriction of the protection section. At least part of the expansion force is offset by the binding force of the protection section. Compared with the related technology where the outermost effective section is only subject to the expansion force inside the cell, the risk of the outermost effective section of the cell in this application breaking under the protection of the protection section is significantly reduced. Furthermore, by setting the protection section to include at least one bent portion, the area most prone to breakage of the first or second electrode of the cell can be protected, extending the service life of the cell.

[0008] In some embodiments, along the winding direction, the protective segment includes at least two curved portions and a flat portion located between the two curved portions.

[0009] In some embodiments, the number of turns m of the protective segment along the winding direction satisfies: 0.5 ≤ m ≤ 3.

[0010] In some embodiments, the first electrode is a negative electrode.

[0011] In some embodiments, along the winding direction, the separator includes an extension beyond the outer end of the protective section, wherein the extension has a number of turns n along the winding direction satisfying: n≥0.5.

[0012] Secondly, embodiments of this application provide a battery cell, including: a first electrode, a separator, and a second electrode. The first electrode, the separator, and the second electrode are stacked and wound together. Both the first electrode and the second electrode include a flat portion and a curved portion that are sequentially connected along the winding direction. The curved portions at both ends of the flat portion are disposed opposite to each other.

[0013] The outer end of the first electrode along the winding direction includes a protective section extending beyond the outer end of the second electrode, and the protective section includes at least one bent portion.

[0014] Thirdly, embodiments of this application provide a battery device, including: a plurality of battery cells as described in any of the above embodiments.

[0015] Fourthly, embodiments of this application provide an energy storage device, comprising: a plurality of battery cells as described in any of the above embodiments or a plurality of battery devices as described in any of the above embodiments, wherein the battery cells or the battery devices are used to store or provide electrical energy.

[0016] Fifthly, embodiments of this application provide an energy storage system, including: a power conversion device and an energy storage device as described in any of the above embodiments, wherein the power conversion device is used to electrically connect a power generation device and the energy storage device.

[0017] Sixthly, embodiments of this application provide an electrical device, including: a battery cell as described in any of the above embodiments, a battery device as described in any of the above embodiments, an energy storage device as described in any of the above embodiments, or an energy storage system as described in any of the above embodiments, wherein the battery cell or the battery device is used to store or provide electrical energy.

[0018] In a seventh aspect, embodiments of this application provide a charging network, including: a charging pile and an energy storage device or an energy storage system as described in any of the above embodiments, wherein the energy storage device is used to provide electrical energy to the charging pile. Attached Figure Description

[0019] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 This application provides schematic diagrams of the structure of an energy storage system according to some embodiments.

[0021] Figure 2 This is a schematic diagram of the structure of a charging network provided in some embodiments of this application;

[0022] Figure 3 This application provides structural schematic diagrams of vehicles for some embodiments;

[0023] Figure 4 Exploded views of the structure of the battery device provided in some embodiments of this application;

[0024] Figure 5 This is a schematic diagram of the structure of a single battery cell in related technologies;

[0025] Figure 6 This is one of the structural schematic diagrams of a battery cell provided in some embodiments of this application;

[0026] Figure 7 This is a second schematic diagram of the structure of a battery cell provided in some embodiments of this application.

[0027] Figure label:

[0028] Energy storage device 1, power conversion device 2, power generation device 3, charging pile 4, connector 5;

[0029] 1000 vehicles;

[0030] Battery device 100;

[0031] Box 10, first box body 11, second box body 12;

[0032] Battery cell 20, battery cell 201, first electrode 2011, separator 2012, second electrode 2013, flat part 2014, bent part 2015, protection section 2016;

[0033] Controller 200; Motor 300. Detailed Implementation

[0034] 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.

[0035] 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.

[0036] In this application, the reference to "embodiment" means that a specific 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 throughout the specification does not necessarily refer to the same embodiment, nor is it a mutually exclusive, independent, or alternative embodiment. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described in this application can be combined with other embodiments.

[0037] 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.

[0038] 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: A existing alone, A and B existing simultaneously, or B existing alone. Additionally, in this application, the character " / " generally indicates that the preceding and following related objects have an "or" relationship.

[0039] In this application, "multiple" refers to two or more (including two), and similarly, "multiple groups" refers to two or more (including two), and "multiple pieces" refers to two or more (including two).

[0040] In this embodiment of the application, the battery cell can be a secondary battery, which refers to a battery cell that can be recharged to activate the active materials and continue to be used after the battery cell has been discharged.

[0041] The battery cell can be a lithium-ion battery, sodium-ion battery, sodium-lithium-ion battery, lithium metal battery, sodium metal battery, lithium-sulfur battery, magnesium-ion battery, nickel-metal hydride battery, nickel-cadmium battery, lead-acid battery, etc., and the embodiments of this application are not limited to this.

[0042] Battery cells can be cylindrical, flat, cuboid, or other shapes, and this application embodiment is not limited to any of these. Battery cells are generally classified into three types according to their packaging method: cylindrical battery cells, square battery cells, and pouch battery cells, and this application embodiment is not limited to any of these types either.

[0043] The battery cell 20 includes a casing, electrode assembly, and electrolyte. The casing houses the electrode assembly and electrolyte. The electrode assembly consists of a positive electrode, a negative electrode, and a separator. The battery cell primarily functions by the movement of metal ions between the positive and negative electrode. The positive electrode includes a positive current collector and a positive active material layer. The positive current collector includes a current collector body and a positive electrode tab. The positive active material layer is coated on the surface of the current collector body, while the positive electrode tab is not coated with the positive active material layer and protrudes from the current collector body. Taking a lithium-ion battery as an example, the material of the positive current collector can be aluminum, and the positive active material can be lithium cobalt oxide, lithium iron phosphate, ternary lithium, or lithium manganese oxide, etc. The negative electrode includes a negative current collector and a negative active material layer. The negative current collector includes a current collector body and a negative electrode tab. The negative active material layer is coated on the surface of the current collector body, while the negative electrode tab is not coated with the negative active material layer and protrudes from the current collector body. The negative electrode current collector can be made of copper, and the negative electrode active material can be carbon or silicon, etc. To ensure that a large current can be passed without melting, there are multiple positive electrode tabs stacked together, and there are multiple negative electrode tabs stacked together.

[0044] The separator can be made of PP (polypropylene) or PE (polyethylene), etc. Furthermore, the electrode assembly can be a wound structure or a stacked structure; this application uses a wound cell structure as an example for illustration.

[0045] The technical solutions described in the embodiments of this application are applicable to various electrical devices that use individual battery cells, such as mobile phones, portable devices, laptops, electric vehicles, electric toys, power tools, vehicles, ships, and spacecraft, including aircraft, rockets, space shuttles, and spacecraft. Individual battery cells are used to store or provide electrical energy.

[0046] The inventors discovered that wound battery cells may expand during use, and this expansion can affect the cell's cycle life, leading to a higher risk of breakage for the outermost electrode. Specifically, because the battery cell casing has a right-angle structure, the electrodes of a wound cell include flat and curved portions connected sequentially along the winding direction. The flat portion of the outer ring of the electrode contacts the casing, and the pressure from the casing can offset some of the expansion force, resulting in a lower risk of breakage. However, the curved portion of the outer ring of the electrode is arc-shaped, and its shape differs from the flat surface or right-angle corner of the casing. This creates areas where the curved portion does not contact the casing, and these areas, lacking the casing pressure, have a higher risk of breakage under expansion forces.

[0047] Based on the above considerations, in order to solve the problem of the high risk of breakage of the outermost electrode of the battery cell due to expansion during use, the inventors, after in-depth research, designed a battery cell including a casing and a battery cell. The battery cell is disposed inside the casing and includes a first electrode, a separator, and a second electrode. The first electrode, the separator, and the second electrode are stacked and wound together. Both the first electrode and the second electrode include a flat portion and a curved portion connected sequentially along the winding direction. The curved portions at both ends of the flat portion are arranged opposite to each other. The outer end of the first electrode along the winding direction includes a protective section that extends beyond the outer end of the second electrode. The protective section includes at least one curved portion.

[0048] In this type of battery cell, by providing a protective section extending beyond the outer end of the first electrode along the winding direction, including the outer end of the second electrode, when the cell expands, the effective section of the first or second electrode located on the outer ring is constrained by the protective section. This effective section is subjected to both the binding force of the protective section and the expansion force within the cell. At least part of the expansion force is offset by the binding force of the protective section. Figure 5 Compared to the related technologies where the outermost effective segment is only subject to the internal expansion force of the cell, the risk of breakage of the outermost effective segment of the cell in this application is significantly reduced under the protection of the protection segment. Furthermore, by setting the protection segment to include at least one bending portion, the area most prone to breakage in the first or second electrode of the cell can be protected, thus extending the service life of the cell.

[0049] The battery apparatus 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 connected in series, parallel, or mixed connections via a busbar.

[0050] In some embodiments, a battery cell assembly is typically formed by arranging multiple battery cells.

[0051] As an example, a battery cell assembly can be a battery module, which is formed by arranging and fixing multiple battery cells together to form an independent module. As another example, a battery module can be formed by bundling multiple battery cells together with cable ties.

[0052] In some embodiments, the battery device may be a battery pack, which includes a housing and one or more individual battery cells housed within the housing.

[0053] As an example, the battery cell assembly can be a battery module, which can be housed in a housing by fixing the battery module in the housing.

[0054] As an example, battery cell assemblies can also be housed in a housing by directly fixing multiple battery cells to the housing.

[0055] As an example, the enclosure may include a first enclosure and a second enclosure. The first enclosure and the second enclosure are fastened together to form a closed space inside the enclosure to house the individual battery cells. Here, "closed" refers to covering or closing, and can be either sealed or unsealed. The first enclosure may be a top cover or a bottom plate.

[0056] As an example, the enclosure may include a top cover, a frame, and a bottom plate. The top cover and bottom plate are connected to the frame, creating an enclosed space inside the enclosure to house the individual battery cells.

[0057] In some embodiments, the housing may be part of the vehicle's chassis structure. For example, a portion of the housing may be at least a part of the vehicle's floor, or a portion of the housing may be at least a part of the vehicle's crossbeams and longitudinal beams.

[0058] The technical solutions described in the embodiments of this application are applicable to various electrical devices that use battery devices, such as mobile phones, portable devices, laptops, electric vehicles, electric toys, power tools, vehicles, ships, and spacecraft, etc. For example, spacecraft include airplanes, rockets, space shuttles, and spacecraft. The battery device is used to store or provide electrical energy.

[0059] This application provides an energy storage device including one or more battery clusters to increase the voltage and capacity of the energy storage device. The battery cluster may include multiple battery devices, which are connected in series via a busbar to increase the voltage of the energy storage device. When the energy storage device includes multiple battery clusters, the multiple battery clusters are connected in parallel to increase the capacity of the energy storage device.

[0060] 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, an energy storage device can store electrical energy during off-peak hours and provide power to relevant users or electrical devices during peak hours. The energy storage system provided in this application embodiment can be any power system that requires energy storage devices.

[0061] In some embodiments, the energy storage device is an energy storage container or an energy storage cabinet.

[0062] In some embodiments, the energy storage device may include a cabinet and one or more battery clusters housed within the cabinet.

[0063] In some embodiments, the energy storage device may include modules such as a thermal management module, a main control module, a central control module, a power distribution module, and a fire protection module.

[0064] As an example, the thermal management module may include a liquid cooling unit that supplies coolant to each battery device via piping to regulate the temperature of the individual battery cells.

[0065] As an example, the main control module can serve as the battery management unit for the battery cluster, used to monitor and manage the battery cluster. The main control module can monitor information such as the current, voltage, power, or temperature of the battery cluster. For instance, it can control the charging and discharging current and voltage of the battery cluster. The main control module includes modules such as an auxiliary battery management unit (SBMU) and a fusion switch.

[0066] As an example, the central control module can serve as the battery management unit for an energy storage device, used to monitor and manage the device. The central control module can monitor information such as the energy storage device's current, voltage, power, state of charge, or temperature. For instance, it can control the charging and discharging current and voltage of the energy storage device. As an example, the central control module includes modules such as an Insulation Monitoring Module (IMM), a Master Battery Management Unit (MBMU), an Ethernet (ETH) module, and a fiber optic conversion module.

[0067] As an example, a fire protection system includes control panels, detectors, alarm devices, etc., used to detect, alarm, or extinguish fires in energy storage systems.

[0068] As an example, the power distribution unit can be used to distribute power to the power modules of the energy storage device.

[0069] The technical solutions described in the embodiments of this application are applicable to various electrical devices that use energy storage devices, such as mobile phones, portable devices, laptops, electric vehicles, electric toys, power tools, vehicles, ships, and spacecraft, etc. For example, spacecraft include airplanes, rockets, space shuttles, and spacecraft. The energy storage device is used to store or provide electrical energy.

[0070] In some embodiments, such as Figure 1 As shown, the energy storage system may include one or more energy storage devices 1 and a power converter system (PCS), wherein the power converter system 2 is used to connect the power generation device 3 and the energy storage device 1. The power generation device 3 is used to generate electrical energy, and the electrical energy generated by the power generation device 3 can be stored in the energy storage device 1 through the power converter system 2. As an example, the power generation device 3 may specifically be a solar panel, a hydroelectric power generation device, a thermal power generation device, a wind power generation device, etc. The specific type of the power generation device 3 is not limited in this application.

[0071] The technical solutions described in the embodiments of this application are applicable to various electrical devices that use energy storage systems, such as mobile phones, portable devices, laptops, electric vehicles, electric toys, power tools, vehicles, ships, and spacecraft, including aircraft, rockets, space shuttles, and spacecraft. Energy storage devices are used to store or provide electrical energy.

[0072] Please refer to Figure 2 This application provides a charging network including a charging pile 4 and an energy storage device 1. The charging pile 4 is electrically connected to the energy storage device 1, and the energy storage device 1 provides electrical energy to the charging pile 4. The charging pile 4 is electrically connected to a battery device in the energy storage device 1 via a cable, and the battery device can provide its stored electrical energy to the charging pile 4. The charging pile 4 has one or more connectors 5, which are used to connect to electrical devices (such as vehicles) to replenish energy to the electrical devices.

[0073] Energy storage devices can be located inside the charging pile (e.g., an integrated energy storage and charging unit) or outside the charging pile.

[0074] This application provides an electrical device that uses a single battery cell, battery device, energy storage device, or energy storage system as a power source. The electrical device can be, but is not limited to, mobile phones, tablets, laptops, electric toys, power tools, electric vehicles, electric cars, ships, and spacecraft. Electric toys can include stationary or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys. Spacecraft can include airplanes, rockets, space shuttles, and spacecraft.

[0075] For ease of explanation, the following embodiments will be described using a vehicle 1000 as an example of an electrical device according to an embodiment of this application.

[0076] Please refer to Figure 3 , Figure 3 This is a schematic diagram of the structure of a vehicle 1000 provided in some embodiments of this application. The vehicle 1000 can be a gasoline-powered vehicle, a natural gas-powered vehicle, or a new energy vehicle. The new energy vehicle can be a pure electric vehicle, a hybrid electric vehicle, or a range-extended electric vehicle, etc. A battery device 100 is installed inside the vehicle, and the battery device 100 can be located at the bottom, front, or rear of the vehicle. The battery device 100 can be used to power the vehicle; for example, the battery device 100 can serve as the vehicle's operating power source. The vehicle may also include a controller 200 and a motor 300. The controller 200 is used to control the battery device 100 to supply power to the motor 300, for example, to meet the power needs of the vehicle during starting, navigation, and driving.

[0077] In some embodiments of this application, the battery device 100 can not only serve as the operating power source for the vehicle, but also as the driving power source for the vehicle, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle.

[0078] Please refer to Figure 4 , Figure 4 This is an exploded view of the structure of a battery device 100 provided in some embodiments of this application. The battery device 100 includes a housing 10 and a plurality of battery cells 20, which are housed within the housing 10. The housing 10 provides assembly space for the battery cells 20, and the housing 10 can adopt various structures. In some embodiments, the housing 10 may include a first housing body 11 and a second housing body 12, which overlap each other, and together define an assembly space for accommodating the battery cells 20. The second housing body 12 may be a hollow structure open at one end, and the first housing body 11 may be a plate-like structure, with the first housing body 11 covering the open side of the second housing body 12, so that the first housing body 11 and the second housing body 12 together define the assembly space; alternatively, the first housing body 11 and the second housing body 12 may both be hollow structures open on one side, with the open side of the first housing body 11 covering the open side of the second housing body 12. Of course, the box 10 formed by the first box body 11 and the second box body 12 can be of various shapes, such as cylinder, cuboid, etc.

[0079] In the battery device 100, multiple battery cells 20 can be connected in series, parallel, or in a mixed configuration. A mixed configuration means that multiple battery cells 20 are connected in both series and parallel configurations. Multiple battery cells 20 can be directly connected in series, parallel, or in a mixed configuration, and then the entire assembly of the multiple battery cells 20 is housed within the housing 10. Alternatively, the battery device 100 can also consist of multiple battery cells 20 first connected in series, parallel, or in a mixed configuration to form battery modules, and then these battery modules are connected in series, parallel, or in a mixed configuration to form a whole, which is then housed within the housing 10. The battery device 100 may also include other structures; for example, it may include a busbar component for electrical connection between the multiple battery cells 20.

[0080] Please refer to Figure 4 , Figure 4 This is a partial structural schematic diagram of a battery device 100 provided in some embodiments of this application. The battery device 100 includes multiple rows of battery cells 20, which are arranged along a first direction. Each row of battery cells 20 includes multiple battery cells 20 arranged along a second direction. The first direction and the second direction are the length direction and the width direction of the housing 10, respectively, and the first direction and the second direction are perpendicular to each other.

[0081] According to some embodiments of this application, this application provides a battery cell 20, including: a casing and a cell 201.

[0082] like Figure 6 and Figure 7 As shown, the battery cell 201 is disposed inside the housing. The battery cell 201 includes a first electrode 2011, a separator 2012, and a second electrode 2013. The first electrode 2011, the separator 2012, and the second electrode 2013 are stacked and wound together.

[0083] In this embodiment, the battery cell 201 is wound and can be flat. One of the first electrode 2011 and the second electrode 2013 is a negative electrode, and the other of the first electrode 2011 and the second electrode 2013 is a positive electrode.

[0084] The first electrode 2011 and the second electrode 2013 both include a flat portion 2014 and a curved portion 2015 connected sequentially along the winding direction. The curved portions 2015 located at both ends of the same flat portion 2014 are arranged opposite to each other, and the flat portions 2014 located at both ends of the same curved portion 2015 are arranged opposite to each other.

[0085] The first electrode 2011 is wound once to form two flat portions 2014 and two curved portions 2015 arranged opposite to each other. The flat portions 2014 and the curved portions 2015 are arranged alternately and connected in sequence.

[0086] The outer end of the first electrode 2011 along the winding direction includes a protection section 2016 that extends beyond the outer end of the second electrode 2013. The protection section 2016 is located on the outermost side of the cell 201 and extends beyond the second electrode 2013, serving to protect the effective section of the inner first electrode 2011 or the second electrode 2013.

[0087] Among them, the first electrode 2011 can be either a negative electrode or a positive electrode.

[0088] For example, Figure 6 As shown, the first electrode 2011 can be configured to form the protection section 2016 by extending the electrode length; or, as... Figure 7 As shown, the protection section 2016 can also be formed by shortening the length of the second electrode 2013.

[0089] When the cell 201 expands, the effective segment of the first electrode 2011 or the second electrode 2013 located on the outer ring is restricted by the protection segment 2016. That is, the effective segment is subjected to the pressure of the protection segment 2016 and the expansion force inside the cell 201. Compared with the related technology where the effective segment of the outermost ring is only subjected to the expansion force inside the cell 201, the risk of the effective segment of the outermost ring of the cell 201 in this application breaking under the protection of the protection segment 2016 is significantly reduced.

[0090] It should be noted that since the protection section 2016 is the area where the first electrode 2011 extends beyond the second electrode 2013 along the winding direction, the protection section 2016 will not exchange metal ions with the second electrode 2013. When the cell 201 expands, even if the protection section 2016 breaks due to the expansion force, it will not affect the normal operation and service life of the cell 201. Furthermore, since the first electrode 2011 and the second electrode 2013 located in the inner ring of the protection section 2016 are protected, the risk of breakage is reduced, thus extending the life of the cell 201.

[0091] Among them, such as Figure 6 and Figure 7 As shown, the protection segment 2016 includes at least one curved portion 2015.

[0092] In this embodiment, the protection segment 2016 may include a bent portion 2015, or a bent portion 2015 and a partially flat portion 2014, or a bent portion 2015 and a flat portion 2014 (the protection segment 2016 may extend beyond the second electrode 2013 by 0.5 turns along the winding direction), or a bent portion 2015 and 1.5 flat portions 2014, or two bent portions 2015 and two flat portions 2014 (the protection segment 2016 may extend beyond the second electrode 2013 by 1 turn along the winding direction), or multiple bent portions 2015 and multiple flat portions 2014 (the protection segment 2016 may extend beyond the second electrode 2013 by at least 2 turns along the winding direction).

[0093] Understandably, since the casing of the battery cell 20 is a right-angle structure, the electrode of the wound cell 201 includes a flat portion 2014 and a curved portion 2015 connected sequentially along the winding direction. The flat portion 2014 of the outer ring of the electrode contacts the casing and can offset part of the expansion force due to the pressure of the casing, so the risk of breakage is relatively small. However, the curved portion 2015 of the outer ring of the electrode is arc-shaped. The arc shape is different from the shape of the casing plane or right-angle corner. There is an area where the curved portion 2015 does not contact the casing. When subjected to expansion force, this area has a higher risk of breakage due to the lack of casing pressure.

[0094] In this embodiment, since the protection section 2016 includes at least one bent portion 2015, the outer side of the bent portion 2015 on at least one side of the effective section of the outermost electrode is provided with a protection section 2016 to protect the area most prone to breakage in the first electrode 2011 or the second electrode 2013 of the battery cell 201 and extend the service life of the battery cell 201.

[0095] According to the battery cell 20 provided in the embodiments of this application, by providing a protection section 2016 extending beyond the outer end of the first electrode 2011 along the winding direction to the outer end of the second electrode 2013, when the cell 201 expands, the effective section of the first electrode 2011 or the second electrode 2013 located on the outer ring is subject to the binding force of the protection section 2016 and the expansion force inside the cell 201 due to the restriction of the protection section 2016. At least part of the expansion force is offset by the binding force of the protection section 2016. Compared with the scheme of the outermost effective section of the related technology, which is only subject to the expansion force inside the cell 201, the risk of the outermost effective section of the cell 201 of this application breaking under the protection of the protection section 2016 is significantly reduced. Furthermore, by providing the protection section 2016 including at least one bent portion 2015, the area most prone to breakage of the first electrode 2011 or the second electrode 2013 of the cell 201 can be protected, thereby extending the service life of the cell 201.

[0096] like Figure 6 and Figure 7As shown, according to some embodiments of this application, along the winding direction, the protection section 2016 includes at least two curved portions 2015 and a flat portion 2014 located between the two curved portions 2015.

[0097] Along the winding direction, the first curved section 2015, the flat section 2014 and the second curved section 2015 are connected in sequence, and the end of the first curved section 2015 away from the flat section 2014 can be connected to the effective section.

[0098] Among them, a partially flat section 2014 may be provided between the first curved section 2015 and the effective section, and the outer end of the second curved section 2015 may be connected to the next flat section 2014.

[0099] Understandably, the longer the protection section 2016 is along the winding direction, the better the restriction effect on the effective section of the outermost electrode sheet. This can effectively resist the expansion force inside the cell 201 on the effective section, reduce the risk of breakage of the outermost effective section, and extend the life of the cell 201.

[0100] In this embodiment, since the protection section 2016 includes at least two bent portions 2015, the outer sides of the bent portions 2015 on both sides of the effective section of the outermost electrode are provided with protection sections 2016. The protection section 2016 can protect the most vulnerable areas of the first electrode 2011 or the second electrode 2013 of the cell 201, and further extend the service life of the cell 201.

[0101] like Figure 6 and Figure 7 As shown, according to some embodiments of this application, the number of turns m of the protection segment 2016 along the winding direction satisfies: 0.5≤m≤3. For example, the number of turns m of the protection segment 2016 along the winding direction can be 0.5 turns, 1 turn, 1.5 turns, 2 turns, 2.3 turns or 3 turns.

[0102] Among them, 0.5 turns include a curved portion 2015 and a flat portion 2014 connected in sequence, and one turn includes two curved portions 2015 and two flat portions 2014 connected in sequence.

[0103] When the number of turns m of the protection section 2016 along the winding direction is 0.5 turns, the protection section 2016 can protect at least one bend 2015 of the outermost effective section, reducing the risk of fracture of the bend 2015 on that side of the outermost effective section; when the number of turns m of the protection section 2016 along the winding direction is 1 turn, the protection section 2016 can protect at least two bends 2015 of the outermost effective section, reducing the risk of fracture in the most vulnerable area of ​​the outermost effective section.

[0104] In this embodiment, by setting the number of turns m of the protection section 2016 along the winding direction to satisfy: 0.5≤m≤3, the risk of breakage of the effective section of the outer ring can be reduced, the service life of the battery cell 201 can be extended, and the cost can be controlled and the difficulty of promotion can be reduced.

[0105] According to some embodiments of this application, the first electrode 2011 can be a negative electrode.

[0106] It is understandable that, since the material cost of the negative electrode is lower than that of the positive electrode, by extending the first electrode 2011 or shortening the second electrode 2013 to form the protection section 2016, costs can be further controlled and the difficulty of promotion can be reduced.

[0107] like Figure 6 and Figure 7 As shown, according to some embodiments of this application, along the winding direction, the separator 2012 includes an extension beyond the outer end of the protection section 2016, and the number of turns n of the extension along the winding direction satisfies: n≥0.5.

[0108] Wherein, n can be 0.5, 2, 3 or larger. By adding an extension beyond the outer end of the protection section 2016, the edge or outer end of the protection section 2016 will not be directly exposed to the electrolyte or other environments that may cause short circuits or damage. At the same time, the protection section 2016 can be confined, thereby providing sufficient physical barrier and electrochemical isolation for the protection section 2016, increasing the safety and stability of the battery, and extending the service life of the cell 201.

[0109] According to some embodiments of this application, this application also provides a battery cell 201, which is disposed in a housing. The battery cell 201 includes a first electrode 2011, a separator 2012, and a second electrode 2013. The first electrode 2011, the separator 2012, and the second electrode 2013 are stacked and wound together. The first electrode 2011 and the second electrode 2013 each include a flat portion 2014 and a curved portion 2015 connected sequentially along the winding direction. The curved portions 2015 at both ends of the flat portion 2014 are disposed opposite to each other.

[0110] In this embodiment, the battery cell 201 is wound and can be flat. One of the first electrode 2011 and the second electrode 2013 is a negative electrode, and the other of the first electrode 2011 and the second electrode 2013 is a positive electrode.

[0111] The first electrode 2011 and the second electrode 2013 both include a flat portion 2014 and a curved portion 2015 connected sequentially along the winding direction, with the curved portions 2015 at both ends of the flat portion 2014 being arranged opposite to each other.

[0112] The first electrode 2011 is wound once to form two flat portions 2014 and two curved portions 2015 arranged opposite to each other. The flat portions 2014 and the curved portions 2015 are arranged alternately and connected in sequence.

[0113] The outer end of the first electrode 2011 along the winding direction includes a protection section 2016 that extends beyond the outer end of the second electrode 2013. The protection section 2016 is located on the outermost side of the cell 201 and extends beyond the second electrode 2013, serving to protect the effective section of the inner first electrode 2011 or the second electrode 2013.

[0114] Among them, the first electrode 2011 can be either a negative electrode or a positive electrode.

[0115] The first electrode 2011 can form the protection section 2016 by extending the electrode length, or by shortening the length of the second electrode 2013.

[0116] When the cell 201 expands, the effective segment of the first electrode 2011 or the second electrode 2013 located on the outer ring is restricted by the protection segment 2016. That is, the effective segment is subjected to the pressure of the protection segment 2016 and the expansion force inside the cell 201. Compared with the related technology where the effective segment of the outermost ring is only subjected to the expansion force inside the cell 201, the risk of the effective segment of the outermost ring of the cell 201 in this application breaking under the protection of the protection segment 2016 is significantly reduced.

[0117] It should be noted that since the protection section 2016 is the area where the first electrode 2011 extends beyond the second electrode 2013 along the winding direction, the protection section 2016 will not exchange metal ions with the second electrode 2013. When the cell 201 expands, even if the protection section 2016 breaks due to the expansion force, it will not affect the normal operation and service life of the cell 201. Furthermore, since the first electrode 2011 and the second electrode 2013 located in the inner ring of the protection section 2016 are protected, the risk of breakage is reduced, thus extending the life of the cell 201.

[0118] The protection section 2016 includes at least one curved portion 2015.

[0119] In this embodiment, the protection segment 2016 may include a bent portion 2015, or a bent portion 2015 and a partially flat portion 2014, or a bent portion 2015 and a flat portion 2014 (the protection segment 2016 may extend beyond the second electrode 2013 by 0.5 turns along the winding direction), or a bent portion 2015 and 1.5 flat portions 2014, or two bent portions 2015 and two flat portions 2014 (the protection segment 2016 may extend beyond the second electrode 2013 by 1 turn along the winding direction), or multiple bent portions 2015 and multiple flat portions 2014 (the protection segment 2016 may extend beyond the second electrode 2013 by at least 2 turns along the winding direction).

[0120] Understandably, since the casing of the battery cell 20 is a right-angle structure, the electrode of the wound cell 201 includes a flat portion 2014 and a curved portion 2015 connected sequentially along the winding direction. The flat portion 2014 of the outer ring of the electrode contacts the casing and can offset part of the expansion force due to the pressure of the casing, so the risk of breakage is relatively small. However, the curved portion 2015 of the outer ring of the electrode is arc-shaped. The arc shape is different from the shape of the casing plane or right-angle corner. There is an area where the curved portion 2015 does not contact the casing. When subjected to expansion force, this area has a higher risk of breakage due to the lack of casing pressure.

[0121] In this embodiment, since the protection section 2016 includes at least one bent portion 2015, the outer side of the bent portion 2015 on at least one side of the effective section of the outermost electrode is provided with a protection section 2016 to protect the area most prone to breakage in the first electrode 2011 or the second electrode 2013 of the battery cell 201 and extend the service life of the battery cell 201.

[0122] According to the battery cell 201 provided in the embodiments of this application, by providing a protection section 2016 extending beyond the outer end of the first electrode 2011 along the winding direction to the outer end of the second electrode 2013, when the battery cell 201 expands, the effective section of the first electrode 2011 or the second electrode 2013 located on the outer ring is subject to the binding force of the protection section 2016 and the expansion force inside the battery cell 201 due to the restriction of the protection section 2016. At least part of the expansion force is offset by the binding force of the protection section 2016. Compared with the scheme of the outermost effective section of the related technology, which is only subject to the expansion force inside the battery cell 201, the risk of the outermost effective section of the battery cell 201 of this application breaking under the protection of the protection section 2016 is significantly reduced. Furthermore, by providing the protection section 2016 including at least one bent portion 2015, the area most prone to breakage of the first electrode 2011 or the second electrode 2013 of the battery cell 201 can be protected, thereby extending the service life of the battery cell 201.

[0123] According to some embodiments of this application, this application also provides a battery device 100, which includes a plurality of battery cells 20.

[0124] According to the battery device 100 provided in the embodiments of this application, since it includes the battery cell 20 in any of the above embodiments, the battery cell 20 is provided with a protection section 2016 extending beyond the outer end of the first electrode 2011 along the winding direction, which extends beyond the outer end of the second electrode 2013. When the cell 201 expands, the effective section of the first electrode 2011 or the second electrode 2013 located on the outer ring is restricted by the protection section 2016. The effective section is subject to the binding force of the protection section 2016 and the expansion force inside the cell 201. At least part of the expansion force is offset by the binding force of the protection section 2016. Compared with the scheme of the outermost effective section of the related technology, which is only subject to the expansion force inside the cell 201, the risk of the outermost effective section of the cell 201 of this application breaking under the protection of the protection section 2016 is significantly reduced. Furthermore, by providing the protection section 2016 including at least one bent portion 2015, the area most prone to breakage of the first electrode 2011 or the second electrode 2013 of the cell 201 can be protected, thereby extending the service life of the cell 201.

[0125] According to some embodiments of this application, this application also provides an energy storage device 1, which includes a plurality of battery cells 20 of any kind, the battery cells 20 being used to store or provide electrical energy; or the energy storage device 1 includes a plurality of battery devices 100 of any kind, the battery devices 100 being used to store or provide electrical energy.

[0126] According to some embodiments of this application, this application also provides an energy storage system, which includes: a power conversion device 2 and an energy storage device 1 of any of the above schemes, wherein the power conversion device 2 is used to electrically connect the power generation equipment 3 and the energy storage device 1.

[0127] According to some embodiments of this application, this application also provides an electrical device. The electrical device includes a battery cell 20 of any of the above-described embodiments, the battery cell 20 being used to store or provide electrical energy; or the electrical device includes a battery device 100 of any of the above-described embodiments, the battery device 100 being used to store or provide electrical energy; or the electrical device includes an energy storage device 1 of any of the above-described embodiments, the battery cell 20 or the battery device 100 being used to store or provide electrical energy; or the electrical device includes an energy storage system of any of the above-described embodiments, the battery cell 20 or the battery device 100 being used to store or provide electrical energy.

[0128] The power supply device can be any of the aforementioned devices or systems that utilize battery device 100.

[0129] According to some embodiments of this application, this application also provides a charging network, which includes a charging pile 4 and an energy storage device 1 or an energy storage system of any of the above schemes, wherein the energy storage device 1 is used to provide electrical energy to the charging pile 4.

[0130] The energy storage device 1 can be located inside the charging pile 4 (e.g., an integrated energy storage and charging unit) or outside the charging pile 4.

[0131] According to some embodiments of this application, see Figure 6 and Figure 7 This application provides a battery cell 20, which includes a casing and a cell 201.

[0132] The battery cell 201 is disposed inside the housing. The battery cell 201 includes a first electrode 2011, a separator 2012, and a second electrode 2013. The first electrode 2011, the separator 2012, and the second electrode 2013 are stacked and wound together.

[0133] The battery cell 201 is wound and can be flat. The first electrode 2011 is the negative electrode, and the second electrode 2013 is the positive electrode. Both the first electrode 2011 and the second electrode 2013 include a flat portion 2014 and a bent portion 2015 connected sequentially along the winding direction. The bent portions 2015 located at both ends of the same flat portion 2014 are arranged opposite to each other, and the flat portions 2014 located at both ends of the same bent portion 2015 are arranged opposite to each other.

[0134] The outer end of the first electrode 2011 along the winding direction includes a protection section 2016 that extends beyond the outer end of the second electrode 2013. The protection section 2016 is located on the outermost side of the cell 201 and extends beyond the second electrode 2013, serving to protect the effective section of the inner first electrode 2011 or the second electrode 2013.

[0135] For example, Figure 6 As shown, the first electrode 2011 can be configured to form the protection section 2016 by extending the electrode length; or, as... Figure 7 As shown, the protection section 2016 can also be formed by shortening the length of the second electrode 2013.

[0136] The protection section 2016 along the winding direction includes at least two bent portions 2015 and a flat portion 2014 located between the two bent portions 2015, so that the outer sides of the bent portions 2015 on both sides of the effective section of the outermost electrode are provided with protection sections 2016. The protection sections 2016 can protect the most vulnerable areas of the first electrode 2011 or the second electrode 2013 of the cell 201, further extending the service life of the cell 201.

[0137] Along the winding direction, the separator 2012 includes an extension section that extends beyond the outer end of the protection section 2016. The extension section has 2 turns n along the winding direction. By adding the extension section that extends beyond the outer end of the protection section 2016, the edge or outer end of the protection section 2016 will not be directly exposed to the electrolyte or other environments that may cause short circuits or damage. At the same time, it can also restrain the protection section 2016, thereby providing sufficient physical barrier and electrochemical isolation for the protection section 2016, increasing the safety and stability of the battery, and extending the service life of the cell 201.

[0138] Unless otherwise specified, all embodiments and optional embodiments of this application can be combined to form new technical solutions.

[0139] Unless otherwise specified, all technical features and optional technical features of this application may be combined to form new technical solutions.

[0140] The above are merely preferred embodiments of this application and are not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A battery cell, characterized in that, include: case; A battery cell is disposed within the housing. The battery cell includes a first electrode, a separator, and a second electrode. The first electrode, the separator, and the second electrode are stacked and wound together. Both the first electrode and the second electrode include a flat portion and a curved portion that are sequentially connected along the winding direction. The curved portions at both ends of the flat portion are disposed opposite to each other. The outer end of the first electrode along the winding direction includes a protective section extending beyond the outer end of the second electrode, and the protective section includes at least one bent portion.

2. The battery cell according to claim 1, characterized in that, Along the winding direction, the protective section includes at least two curved portions and a flat portion located between the two curved portions.

3. The battery cell according to claim 1 or 2, characterized in that, The number of turns m of the protective section along the winding direction satisfies: 0.5≤m≤3.

4. The battery cell according to any one of claims 1-3, characterized in that, The first electrode is the negative electrode.

5. The battery cell according to any one of claims 1-4, characterized in that, Along the winding direction, the separator includes an extension beyond the outer end of the protective section, and the number of turns n of the extension along the winding direction satisfies: n≥0.

5.

6. A battery cell, characterized in that, include: A first electrode, a separator, and a second electrode are stacked and wound together. The first electrode, the separator, and the second electrode each include a flat portion and a curved portion connected sequentially along the winding direction. The curved portions at both ends of the flat portion are arranged opposite to each other. The outer end of the first electrode along the winding direction includes a protective section extending beyond the outer end of the second electrode, and the protective section includes at least one bent portion.

7. A battery device, characterized in that, include: Multiple battery cells according to any one of claims 1-5.

8. An energy storage device, characterized in that, include: A plurality of battery cells as described in any one of claims 1-5 or a plurality of battery devices as described in claim 7, wherein the battery cells or the battery devices are used to store or provide electrical energy.

9. An energy storage system, characterized in that, include: The power conversion device and the energy storage device as described in claim 8, wherein the power conversion device is used to electrically connect the power generation equipment and the energy storage device.

10. An electrical appliance, characterized in that, include: The battery cell as described in any one of claims 1-5, the battery device as described in claim 7, the energy storage device as described in claim 8, or the energy storage system as described in claim 9, wherein the battery cell or the battery device is used to store or provide electrical energy.

11. A charging network, characterized in that, include: The charging pile and the energy storage device as described in claim 8 or the energy storage system as described in claim 9, wherein the energy storage device is used to provide electrical energy to the charging pile.

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