Battery monomer, battery device, electric equipment and charging network

Abstract

The embodiment of the utility model discloses a battery monomer, a battery device, electric equipment and a charging network. The battery cell includes: an electrode terminal; an electrode assembly having a tab; the electric connecting piece comprises a first connecting part, a second connecting part and a body part; the first connecting part is used for being electrically connected with an electrode terminal; the second connecting part is used for being electrically connected with a tab; the body part is used for electrically connecting the first connecting part and the second connecting part; wherein the body part is provided with a first structure and a second structure, and the strength of the first structure is different from that of the second structure. According to the battery monomer, the battery device, the electric equipment and the charging network provided by the embodiment of the invention, the connection reliability of the electric connector in the battery monomer can be improved.

Description

Technical Field

[0001] This application relates to the field of batteries, and more specifically, to a battery cell, a battery device, an electrical device, and a charging network. Background Technology

[0002] In the development of battery technology, battery performance is an issue that cannot be ignored. Battery performance not only affects the development and application of battery-related products but also influences consumer acceptance of these products. Electrical connectors are installed within the battery cells, acting as a bridge between the internal and external parts of the battery and playing a crucial role in battery safety and power supply stability. Therefore, improving the reliability of the electrical connectors within the battery cells is extremely important. Utility Model Content

[0003] This application provides a battery cell, a battery device, an electrical appliance, and a charging network, which can improve the connection reliability of the electrical connectors inside the battery cell.

[0004] In a first aspect, this application provides a battery cell, comprising: an electrode terminal; an electrode assembly having tabs; and an electrical connector including a first connecting portion, a second connecting portion, and a body portion; the first connecting portion being used for electrical connection with the electrode terminal; the second connecting portion being used for electrical connection with the tabs; and the body portion being used for electrical connection between the first connecting portion and the second connecting portion, wherein the body portion has a first structure and a second structure, the first structure and the second structure having different strengths.

[0005] In the technical solution of this application embodiment, by setting two structures with different strengths on the body of the electrical connector, compared with a single-strength structure, the body has higher stability and fatigue resistance, and can withstand loads of different types and sizes, thereby improving the connection performance of the electrical connectors inside the battery cell. Furthermore, the strength performance of the two structures can be flexibly adjusted according to different usage scenarios to meet various complex structural and functional requirements.

[0006] In some embodiments of the first aspect, the body portion is provided with a fusible portion, which is configured to melt when the current on the electrical connector is greater than or equal to a preset threshold, thereby disconnecting the first connection portion and the second connection portion; wherein the fusible portion includes the first structure and the second structure, and the first structure and the second structure are made of different materials.

[0007] In this embodiment, by using two different material structures for the fuse section, the structural strength and fusing threshold of the fuse section can be flexibly designed. Compared to a fuse section made of a single material, a fuse section with two different material structures can have higher strength and stiffness, thereby improving the connection reliability of the internal electrical connectors of the battery cell. At the same time, it can also have a lower fusing threshold, enabling the fuse section to fuse in a timely manner, reducing the risk of battery cell failure due to failure to fuse in time, and improving the safety performance of the battery cell.

[0008] In some embodiments of the first aspect, the fused portion is located in the region of the body portion with the smallest cross-sectional area along the thickness direction of the electrical connector.

[0009] In this embodiment, the region with the smallest cross-sectional area along the thickness direction of the electrical connector is the region through which the current passes through the smallest area. This region has the highest impedance, and when a short-circuit current occurs on the electrical connector, this region will experience severe heating. By placing a fuse in this region, when the current on the electrical connector is greater than or equal to a preset threshold, the fuse can quickly melt and break the current between the first and second connecting parts, thereby reducing the risk of battery cell failure due to the fuse not melting in time.

[0010] In some embodiments of the first aspect, the hardness of the first structure is greater than the hardness of the second structure.

[0011] In this embodiment, two different materials are used to form the fuse portion, and the hardness of the first structure is greater than that of the second structure. This improves the overall mechanical strength of the fuse portion, enhances the manufacturability of the electrical connector, and reduces the risk of bending or even breaking of the electrical connector during the production of battery cells.

[0012] In some embodiments of the first aspect, the melting point of the second structure is lower than that of the first structure.

[0013] In this embodiment, when a short circuit occurs outside the battery cell, a large instantaneous short-circuit current will appear on the electrical connector. The second structure in the fuse will melt, which will cause the overcurrent area of ​​the fuse to decrease sharply and the resistance of the fuse to increase. This will cause the first structure to heat up more intensely, accelerate the melting of the first structure, thereby cutting off the external current of the battery cell and reducing the risk of battery cell failure.

[0014] In some embodiments of the first aspect, the fuse portion includes at least one first structure and at least one second structure, wherein the at least one first structure and at least one second structure are alternately arranged in sequence along a first direction.

[0015] In the embodiments of this application, by alternating the first structure and the second structure, the strength of the fused portion can be effectively increased, thereby improving the manufacturability and mechanical strength of the electrical connector and reducing the risk of bending or even breaking of the electrical connector during the production of the battery cell.

[0016] In some embodiments of the first aspect, the first direction is perpendicular to the thickness direction of the electrical connector, and the projections of the at least one first structure and the at least one second structure in the thickness direction of the electrical connector are parallel to each other.

[0017] In this embodiment, by arranging the first structure and the second structure parallel to each other, when the current on the electrical connector reaches a certain preset threshold, the second structure melts quickly, causing the cross-sectional area of ​​the melted part to decrease rapidly, thereby increasing the resistance of the area. The remaining first structure heats up more intensely, causing the first structure to melt quickly as well, thereby cutting off the current on the electrical connector and reducing the risk of battery cell failure.

[0018] In some embodiments of the first aspect, the first direction is perpendicular to the thickness direction of the electrical connector, and the projections of two adjacent second structures in the at least one second structure in the thickness direction of the electrical connector have an included angle.

[0019] In this embodiment, the first structure and the second structure are intertwined. On the one hand, this can improve the connection strength of the fusible part and reduce the risk of bending or breaking of the electrical connector. On the other hand, as the second structure is made of a low-melting-point material, when the battery cell is short-circuited externally, the fusible part heats up violently due to the instantaneous large current, which enables the second structure to melt quickly. This further reduces the cross-sectional area of ​​the fusible part, and the first structure melts faster, thereby disconnecting the current on the electrical connector, reducing the risk of battery cell failure, and improving the safety performance of the battery cell.

[0020] In some embodiments of the first aspect, the first direction is the thickness direction of the electrical connector.

[0021] In this embodiment, by setting the first and second structures along the thickness direction of the electrical connector, the electrical connector can have sufficient connection strength during battery cell production or normal use, reducing the risk of battery cell damage due to electrical connector deformation. When the current on the electrical connector reaches a certain preset threshold, the second structure melts quickly, causing the cross-sectional area of ​​the melted part to decrease rapidly, thereby increasing the resistance in that area. The remaining first structure heats up more intensely, causing the first structure to melt quickly as well, thereby cutting off the current on the electrical connector and reducing the risk of battery cell failure.

[0022] In some embodiments of the first aspect, the ratio of the volume of the first structure to the volume of the fuse portion is [0.5, 0.8].

[0023] In this embodiment, the first structure has higher hardness than the second structure, and the ratio of the volume of the first structure to the volume of the fusible part is greater than 0.5, which can improve the structural strength of the fusible part and enhance the connection reliability of the electrical connector. The ratio of the volume of the first structure to the volume of the fusible part is less than 0.8, that is, the volume ratio of the second structure should be greater than 0.2. In this way, when a short circuit current occurs on the electrical connector and reaches a preset threshold, the second structure can melt quickly due to its low melting point, so that only the first structure remains in the fusible part. The current-passing area of ​​the fusible part is reduced and the impedance is increased, so that the first structure can also melt quickly, thereby cutting off the current on the electrical connector and reducing the risk of battery cell failure due to continuous heating caused by excessive current.

[0024] In some embodiments of the first aspect, the material of the first structure includes aluminum or copper.

[0025] In the embodiments of this application, aluminum and copper both have good electrical conductivity and sufficient strength, which can improve the connection strength of electrical connectors and reduce the risk of damage to battery cells due to deformation of electrical connectors.

[0026] In some embodiments of the first aspect, the material of the second structure is tin, bismuth, lead, tin-containing alloys, bismuth-containing alloys, or lead-containing alloys.

[0027] In the embodiments of this application, the second structure uses tin, bismuth, lead, tin alloy, bismuth alloy, or lead alloy, which not only has good conductivity but also allows the melting temperature of the fuse to be low. When a short circuit occurs outside the battery cell, the instantaneous large short-circuit current generates intense heat through the fuse, enabling the second structure to melt quickly, thereby providing good fuse protection for the battery cell.

[0028] In a second aspect, an electrical connector is provided for a battery cell, comprising: a first connecting portion for electrically connecting to the electrode terminals of the battery cell; a second connecting portion for electrically connecting to the tabs of the battery cell; and a body portion for electrically connecting the first connecting portion and the second connecting portion, the body portion comprising a first structure and a second structure, the first structure and the second structure having different strengths.

[0029] Thirdly, a battery device is provided, comprising a plurality of battery cells according to the second aspect or any one of the embodiments of the second aspect.

[0030] Fourthly, an electrical device is provided, comprising a plurality of battery cells according to the second aspect or any one of the second aspects, or a plurality of battery devices according to the third aspect or any one of the third aspects, wherein the battery cells or the battery devices are used to provide or store electrical energy.

[0031] Fifthly, a charging network is provided, including a charging pile and an electrical device according to the fourth aspect or any embodiment of the fourth aspect, the electrical device being used to provide power to the charging pile. Attached Figure Description

[0032] Figure 1 This is a schematic diagram of an energy storage device according to an embodiment of this application;

[0033] Figure 2 This is a schematic diagram of the battery device according to an embodiment of this application;

[0034] Figure 3 This is a schematic diagram of the structure of a single battery cell according to an embodiment of this application;

[0035] Figure 4 This is a schematic diagram of the structure of the electrical connector according to an embodiment of this application;

[0036] Figure 5 This is a top view of an electrical connector according to an embodiment of this application;

[0037] Figure 6 This is a top view schematic diagram of an electrical connector according to another embodiment of this application;

[0038] Figure 7 This is a top view schematic diagram of an electrical connector according to another embodiment of this application;

[0039] Figure 8 This is a top view schematic diagram of an electrical connector according to another embodiment of this application;

[0040] Figure 9 This is a top view schematic diagram of an electrical connector according to another embodiment of this application;

[0041] Figure 10 This is a top view of the fuse portion according to an embodiment of this application;

[0042] Figure 11 This is a top view of the fuse portion according to another embodiment of this application;

[0043] Figure 12 This is a top view of the fuse portion according to another embodiment of this application;

[0044] Figure 13 This is a cross-sectional structural diagram of the electrical connector according to an embodiment of this application;

[0045] Figure 14 This is a cross-sectional structural schematic diagram of an electrical connector according to another embodiment of this application;

[0046] Figure 15 This is a top view schematic diagram of an electrical connector according to another embodiment of this application;

[0047] Figure 16 This is a cross-sectional structural diagram of the fuse portion according to an embodiment of this application;

[0048] Figure 17 This is a cross-sectional structural diagram of the fuse portion according to another embodiment of this application;

[0049] Figure 18 This is a schematic diagram of the energy storage system according to an embodiment of this application;

[0050] Figure 19 This is a schematic diagram of the charging network structure according to an embodiment of this application.

[0051] The labels for the attached figures are as follows:

[0052] 1. Energy storage system; 2. Energy storage device; 3. Power conversion equipment; 4. Power generation equipment; 5. Charging network; 6. Charging pile; 7. Connector.

[0053] Battery assembly 10, housing 11, first housing section 111, second housing section 112; battery cell 20, outer casing 21, shell 211, end cap 212, electrode assembly 22, tab 221, positive tab 221a, negative tab 221b, electrical connector 23, pressure relief mechanism 213, electrode terminal 214, positive electrode terminal 214a, negative electrode terminal 214b;

[0054] First connecting part 231, second connecting part 232, body part 233, fusion part 234, first structure 2341, second structure 2342, alloy layer 234a.

[0055] The accompanying drawings are not drawn to scale. Detailed Implementation

[0056] The technical solutions in the embodiments of this application will now be described with reference to the accompanying drawings.

[0057] 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.

[0058] 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.

[0059] 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.

[0060] 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.

[0061] 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.

[0062] 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.

[0063] 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).

[0064] Unless otherwise specified, all embodiments and optional embodiments of this application can be combined to form new technical solutions.

[0065] Unless otherwise specified, all technical features and optional technical features of this application may be combined to form new technical solutions.

[0066] 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.

[0067] 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.

[0068] A single battery cell typically includes an electrode assembly. The electrode assembly includes a positive electrode, a negative electrode, and a separator, with the separator positioned between the positive and negative electrodes. During the charging and discharging process of a single battery cell, active ions (such as lithium ions) repeatedly insert and extract between the positive and negative electrodes. The separator, positioned between the positive and negative electrodes, prevents short circuits while allowing active ions to pass through.

[0069] In some embodiments, the positive electrode may be a positive electrode sheet, which may include a positive electrode current collector and a positive electrode active material disposed on at least one surface of the positive electrode current collector.

[0070] As an example, the positive current collector has two surfaces opposite each other in its own thickness direction, and the positive active material is disposed on either or both of the two opposite surfaces of the positive current collector.

[0071] In some embodiments, the negative electrode may be a negative electrode sheet, and the negative electrode sheet may include a negative electrode current collector.

[0072] As an example, the negative electrode sheet may include a negative electrode current collector and a negative electrode active material disposed on at least one surface of the negative electrode current collector.

[0073] As an example, the negative electrode current collector has two surfaces opposite each other in its own thickness direction, and the negative electrode active material is disposed on either or both of the two opposite surfaces of the negative electrode current collector.

[0074] In some embodiments, the positive current collector can be made of aluminum, and the negative current collector can be made of copper.

[0075] In some embodiments, the electrode assembly further includes an isolator disposed between the positive and negative electrodes.

[0076] In some embodiments, the separator is a separator membrane. This application does not impose any particular limitation on the type of separator membrane; any known porous separator membrane with good chemical and mechanical stability can be selected.

[0077] In some embodiments, the separator is a solid electrolyte. The solid electrolyte is disposed between the positive and negative electrodes, serving both to transport ions and to isolate the positive and negative electrodes.

[0078] In some embodiments, the battery cell also includes an electrolyte, which acts as a conductor of ions between the positive and negative electrodes. This application does not impose specific limitations on the type of electrolyte; it can be selected according to requirements. The electrolyte can be liquid, gel, or solid.

[0079] In some embodiments, the electrolyte may optionally include additives. For example, additives may include negative electrode film-forming additives, positive electrode film-forming additives, and additives that can improve certain properties of the battery cell, such as additives that improve the overcharge / fast charge performance of the battery cell, additives that improve the high-temperature performance of the battery cell, and additives that improve the low-temperature performance of the battery cell.

[0080] The electrode assembly can be a wound structure, a stacked structure, or a hybrid structure of wound and stacked.

[0081] In some implementations, the electrode assembly is a wound structure. The positive and negative electrode sheets are wound into a wound structure.

[0082] In some implementations, the electrode assembly is a stacked structure.

[0083] As an example, multiple positive and negative electrodes can be set, and multiple positive and multiple negative electrodes can be stacked alternately.

[0084] As an example, multiple positive electrode plates can be provided, and negative electrode plates can be folded to form multiple stacked folded segments, with a positive electrode plate sandwiched between adjacent folded segments.

[0085] As an example, both the positive and negative electrode plates are folded to form multiple stacked folded segments.

[0086] As an example, multiple separators can be provided, each positioned between any adjacent positive or negative electrode plates.

[0087] As an example, the separators can be continuously arranged, either by folding or rolling between any adjacent positive or negative electrode plates.

[0088] In some embodiments, the electrode assembly can be cylindrical, flat, or polygonal, etc.

[0089] In some embodiments, the electrode assembly is provided with tabs that allow current to be drawn from the electrode assembly. The tabs include a positive tab and a negative tab.

[0090] In some embodiments, the battery cell may include a casing. The casing may be a steel casing, an aluminum casing, a plastic casing (such as a polypropylene casing), a composite metal casing (such as a copper-aluminum composite casing), or an aluminum-plastic film, etc. In some embodiments, the casing may be a sealed structure or a non-sealed structure. As an example, when the casing is a non-sealed structure, the casing serves to protect the electrode assembly, and a sealing bag is included between the casing and the electrode assembly to encapsulate the electrode assembly and electrolyte. Specifically, the sealing bag may be a bag-shaped insulating component or an aluminum-plastic film. When the casing is a sealed structure, it is used to encapsulate components such as the electrode assembly and electrolyte.

[0091] As an example, the battery cell 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.

[0092] In some embodiments, the housing includes an end cap and a housing, the housing having an opening, and the end cap covering the opening. The housing may have one or more openings. The end cap may also have one or more.

[0093] In some embodiments, at least one electrode terminal is provided on the housing, and the electrode terminal is electrically connected to the tab. The electrode terminal can be directly connected to the tab, or it can be indirectly connected to the tab through a current collector. The electrode terminal can be provided on the end cap or on the housing.

[0094] 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.

[0095] In some embodiments, a battery cell assembly is typically formed by arranging multiple battery cells.

[0096] 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.

[0097] 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.

[0098] 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.

[0099] As an example, battery cell assemblies can also be housed in a housing by directly fixing multiple battery cells to the housing.

[0100] 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.

[0101] 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.

[0102] 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.

[0103] The technical solutions described in the embodiments of this application are applicable to various electrical devices that use individual battery cells.

[0104] For example, electrical equipment can be 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.

[0105] For example, electrical equipment can also be an energy storage device, which may include multiple battery devices. Energy storage devices can be of various types and sizes. For instance, an energy storage device can be such as... Figure 1The energy storage container shown could also be an energy storage cabinet. The energy storage device can be, for example, a regular cuboid structure, where the six faces of the cuboid are the six outer walls of the energy storage device. Setting the energy storage device as a cuboid structure facilitates its fixed placement and transportation. Of course, the energy storage device can also be of other shapes; for example, at least one wall of the energy storage device may be inclined.

[0106] Energy storage devices include one or more battery clusters to increase the voltage and capacity of the energy storage device. A battery cluster may include multiple battery units connected in series via a busbar to increase the voltage of the energy storage device. When an energy storage device includes multiple battery clusters, the battery clusters are connected in parallel to increase the capacity of the energy storage device.

[0107] 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 equipment during peak hours. The energy storage system provided in this application embodiment can be any power system that requires energy storage devices.

[0108] In some embodiments, the energy storage device is an energy storage container or an energy storage cabinet.

[0109] In some embodiments, the energy storage device may include a cabinet and one or more battery clusters housed within the cabinet.

[0110] 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.

[0111] 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.

[0112] 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.

[0113] 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.

[0114] 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.

[0115] As an example, the power distribution unit can be used to distribute power to the power modules of the energy storage device.

[0116] The development of battery technology must consider multiple design factors simultaneously, such as performance parameters like energy density, cycle life, discharge capacity, and charge / discharge rate. Additionally, the reliability and safety of battery use must also be considered. The electrical connectors inside a battery cell, used to connect the electrode terminals and tabs, are critical components in the current path. In the event of a short circuit in the external connection circuit of the battery cell, the electrical connectors need to melt as quickly as possible to reduce the risk of short circuits and improve the safety performance of the battery cell. However, during normal charge and discharge, the electrical connectors must be able to stably connect the conductive structures on the battery cell, facilitating the flow of internal and external currents. This reduces the occurrence of deformation or breakage due to external pressure or other factors, improving the connection stability of the electrical connectors. Therefore, the structure of the electrical connectors needs to be rationally designed to ensure safe and reliable connection performance.

[0117] This application provides a battery cell, a battery device, an electrical appliance, and a charging network. The battery cell includes electrode terminals, electrode assemblies, and electrical connectors. The electrode assembly has tabs. The electrical connector includes a first connecting portion, a second connecting portion, and a body portion. The first connecting portion is used for electrical connection to the electrode terminals. The second connecting portion is used for electrical connection to the tabs. The body portion is used for electrical connection between the first connecting portion and the second connecting portion. The body portion has a first structure and a second structure, with the first structure and the second structure having different strengths. In the battery cell, battery device, electrical appliance, and charging network, by providing two structures with different strengths for the body portion of the electrical connector, compared to a single-strength structure, the body portion has higher stability and fatigue resistance, can withstand loads of different types and sizes, and improves the connection performance of the electrical connectors inside the battery cell. Furthermore, the strength performance of the two structures can be flexibly adjusted according to different usage scenarios to meet various complex structural and functional requirements.

[0118] Figure 2 A partial structural schematic diagram of a battery device according to an embodiment of this application is shown. Figure 2 As shown, the battery device 10 of this application embodiment may include a plurality of battery cells 20 to meet different power usage requirements. The shape of the battery cell 20 in this application embodiment can be set according to actual application. For example, the battery cell 20 can be as follows: Figure 2 The cylindrical shape shown, or it could be different. Figure 2 The embodiments shown may be cuboids or other shapes, but are not limited to these.

[0119] It should be understood that, such as Figure 2 As shown, the battery device 10 of this embodiment may further include a housing 11, which can be used to accommodate multiple battery cells 20. The housing 11 of this embodiment has a hollow interior, and the multiple battery cells 20 are accommodated within the housing 11. The housing 11 may include two parts, referred to herein as a first housing portion 111 and a second housing portion 112, which are fastened together. The shapes of the first housing portion 111 and the second housing portion 112 can be determined according to the shape of the components housed inside, for example, according to the shape of the combination of the multiple battery cells 20 housed inside. At least one of the first housing portion 111 and the second housing portion 112 has an opening. The multiple battery cells 20 are connected in parallel, series, or mixed configurations and placed within the housing 11 formed by the fastening of the first housing portion 111 and the second housing portion 112.

[0120] Figure 3 This paper shows a partial structural schematic diagram of the battery cell 20 according to an embodiment of this application. Figure 4 A schematic diagram of the structure of the electrical connector 23 according to an embodiment of this application is shown, as follows: Figure 3and Figure 4 As shown, this application embodiment provides a battery cell 20, which may include: an electrode terminal 214; an electrode assembly 22 having a tab 221; and an electrical connector 23 including a first connecting portion 231, a second connecting portion 232, and a body portion 233; the first connecting portion 231 is used to electrically connect to the electrode terminal 214, the second connecting portion 232 is used to electrically connect to the tab 221, and the body portion 233 is used to electrically connect the first connecting portion 231 and the second connecting portion 232; wherein, the body portion 233 has a first structure 2341 and a second structure 2342, and the first structure 2341 and the second structure 2342 have different strengths.

[0121] In some embodiments, the battery cell 20 may further include a housing 21, an electrode terminal 214 disposed on the housing 21, an electrode assembly 22 provided with a tab 221, and an electrical connector 23 electrically connected to the electrode terminal 214 and the tab 221 respectively.

[0122] It should be understood that tab 221 refers to a conductive element extending from electrode assembly 22, used to release or charge electrical energy in electrode assembly 22. Electrode terminal 214 refers to a conductive element disposed on housing 21, which is connected to tab 221 of electrode assembly 22 to output electrical energy from battery cell 20 or charge battery cell 20. Electrical connector 23 refers to a conductive element disposed in battery cell 20, which connects tab 221 and electrode terminal 214 to achieve electrical connection between tab 221 and electrode terminal 214.

[0123] In some embodiments, a pressure relief mechanism may be provided on the housing 21. For example... Figure 3 As shown, the battery cell 20 may also include a pressure relief mechanism 213. The pressure relief mechanism 213 is used to release the internal gas of the battery cell.

[0124] As an example, the internal pressure or temperature of the battery cell 20 is actuated to release the internal pressure or temperature when it reaches a predetermined threshold. When the internal pressure or temperature of the battery cell 20 reaches the predetermined threshold, the pressure relief mechanism 213 is activated or a weak structure provided in the pressure relief mechanism 213 is destroyed, thereby forming an opening or channel for the release of internal pressure or temperature. The threshold design varies depending on the design requirements. The threshold may depend on the materials of one or more of the positive electrode, negative electrode, electrolyte, and separator in the battery cell.

[0125] As an example, the pressure relief mechanism 213 can be integrally formed with the housing 21.

[0126] As an example, the pressure relief mechanism 213 can also be separately configured and connected to the housing 21.

[0127] The term "actuation" as used in this application refers to the pressure relief mechanism 213 being activated or undergoing a certain state, thereby releasing the internal pressure and temperature of the battery cell 20. The actions of the pressure relief mechanism 213 may include, but are not limited to: movement of components within the pressure relief mechanism 213 to form an exhaust channel, rupture, breakage, tearing, or opening of at least a portion of the pressure relief mechanism 213, etc. When the pressure relief mechanism 213 is actuated, the high-temperature, high-pressure substances inside the battery cell 20 are discharged outwards from the actuated portion as exhaust materials. This method enables pressure and temperature relief of the battery cell 20 under controllable pressure or temperature conditions, thereby preventing potentially more serious accidents.

[0128] The emissions from the battery cell 20 mentioned in this application include, but are not limited to: electrolyte, dissolved or split positive and negative electrode plates, fragments of separators, high-temperature and high-pressure gases generated by the reaction, flames, etc.

[0129] In some embodiments, the housing 21 may include a housing 211 and an end cap 212, the housing 211 having an opening, the end cap 212 covering the opening, and the electrode terminal 214 disposed on the end cap 212.

[0130] In some embodiments, the housing 21 may be provided with one or more electrode terminals 214, for example, such as Figure 3 As shown, the housing 21 may be provided with two electrode terminals 214, including a positive electrode terminal 214a and a negative electrode terminal 214b. The positive electrode terminal 214a is electrically connected to the positive electrode tab 221a, and the negative electrode terminal 214b is electrically connected to the negative electrode tab 221b.

[0131] In some embodiments, multiple electrical connectors 23 may be provided, for example, such as Figure 3 As shown, two electrical connectors 23 can be provided. One of the two electrical connectors 23 is connected to the positive electrode terminal 214a and the positive electrode tab 221a respectively, so that the current between the positive electrode terminal 214a and the positive electrode tab 221a is conducted; the other of the two electrical connectors 23 is connected to the negative electrode terminal 214b and the negative electrode tab 221b respectively, so that the current between the negative electrode terminal 214b and the negative electrode tab 221b is conducted.

[0132] It should be understood that the electrical connector 23 can be a sheet-like structure with a certain thickness, and can be any shape such as rectangular, circular, elliptical, polygonal, or other irregular shapes. The shape of the electrical connector 23 can be changed and adjusted according to the structural form and positional relationship between the tab 221 and the electrode terminal 214 in the battery cell 20. For example, the first connecting part 231 of the electrical connector 23 can also have an upwardly protruding structure, with the top surface of the protruding part contacting the electrode terminal 214 to achieve an electrical connection between the first connecting part 231 and the electrode terminal 214. As another example, the electrical connector 23 can also have two wings as a second connecting part 232 for electrical connection with the tab 221.

[0133] It should be understood that the first connecting portion 231 of the electrical connector 23 is electrically connected to the electrode terminal 214, and the second connecting portion 232 of the electrical connector 23 is electrically connected to the tab 221. The body portion 233 of the electrical connector 23 is disposed between the first connecting portion 231 and the second connecting portion 232, which allows current to be conducted between the electrode terminal 214 and the tab 221, realizing current communication between the inside and outside of the battery cell. The first connecting portion 231 can be fixed to the electrode terminal 214 by laser welding, and the second connecting portion 232 can be fixed to the tab 221 by laser welding. The materials of the first connecting portion 231 and the second connecting portion 232 can be metals such as aluminum and copper, or other conductive materials such as aluminum alloys and copper alloys.

[0134] The projections of the first connecting portion 231 and the second connecting portion 232 in the thickness direction of the electrical connector 23 can be rectangular, circular, or any other arbitrary shape. In some embodiments, the shapes of the first connecting portion 231 and the second connecting portion 232 can respectively correspond to the electrode terminal 214 and the tab 221 in the battery cell 20. For example, the first connecting portion 231 can be configured to have a circular projection in the thickness direction of the electrical connector 23 to match the shape of the electrode terminal 214, and the second connecting portion 232 can be configured to be elongated to match the shape of the tab 221.

[0135] It should be understood that the body portion 233 has a first structure 2341 and a second structure 2342. This can mean that the body portion 233 is composed of the first structure 2341 and the second structure 2342, or that the first structure 2341 and the second structure 2342 are located at a certain position in the body portion 233. That is, the first structure 2341 and the second structure 2342 can be located in any region or all regions of the body portion 233. By providing two structures of different strengths to the body portion, compared with a single-strength structure, the body portion has higher stability and fatigue resistance, can resist loads of different types and sizes, and improves the connection performance of electrical connectors inside the battery cell. In addition, the strength performance of the two structures can be flexibly adjusted according to different usage scenarios to meet various complex structural and functional requirements.

[0136] In some embodiments, the main body 233 is provided with a fuse portion 234. The fuse portion 234 is configured to melt when the current on the electrical connector 23 is greater than or equal to a preset threshold, thereby disconnecting the first connection portion 231 and the second connection portion 232. The fuse portion 234 includes a first structure 2341 and a second structure 2342, and the first structure 2341 and the second structure 2342 are made of different materials.

[0137] For ease of description, two reference directions are defined on a plane perpendicular to the thickness of the electrical connector 23. Figure 4 For example, the direction of current flow on the fuse part 234 is direction X1, and the direction perpendicular to direction X1 is direction X2. It should be understood that the direction of current flow can be as follows: Figure 4 The direction X1 shown can also be the opposite direction to X1. For example, when the battery cell 20 is charging, the current flows from the electrode terminal 214 through the first connection portion 231, the body portion 233 and the second connection portion 232 to the tab 221. At this time, the current flow direction on the fuse portion 234 is the direction X1. When the battery cell 20 is discharging, the current flows from the tab 221 through the second connection portion 232, the body portion 233 and the first connection portion 231 to the electrode terminal 214. At this time, the current flow direction on the fuse portion 234 is the opposite direction to X1.

[0138] In this embodiment, after the fusible part 234 is heated and melted, the first connecting part 231 and the second connecting part 232 can be disconnected. It can be understood that the length of the fusible part 234 along the X2 direction should be equal to the length of the electrical connector 23 along the X2 direction. Therefore, when the current on the electrical connector 23 is greater than or equal to a preset threshold, the fusible part 234 melts completely in the X2 direction, thereby cutting off the current between the first connecting part 231 and the second connecting part 232.

[0139] The fuse element 234 is typically made of a low-melting-point metal so that it can melt as much as possible when the battery cell 20 experiences an external circuit short circuit. However, low-melting-point metals have relatively low strength, making the electrical connector 23 difficult to process. Furthermore, the electrical connector may deform during battery cell assembly, which could easily lead to the tab 221 being torn or damaged, thus affecting the safety performance of the battery cell 20.

[0140] Therefore, by using two different material structures for the fuse element 234, based on the original single material, the structural strength and fusing threshold of the fuse element 234 can be flexibly designed. Compared with a fuse element made of a single material, a fuse element with two different material structures can have higher strength and stiffness, thereby improving the connection reliability of the electrical connectors inside the battery cell. At the same time, it can also have a lower fusing threshold, enabling the fuse element to fuse in time, reducing the risk of battery cell failure due to failure to fuse in time, and improving the safety performance of the battery cell.

[0141] For example, if the original fuse portion 234 has low strength, a high-strength material can be embedded into it to increase the strength and rigidity of the electrical connector 23 and improve its connection reliability. Alternatively, if the original fuse portion 234 has a high fusing threshold, a low-melting-point material can be embedded into it to lower the fusing threshold, allowing the fuse portion to fuse promptly and protect the battery cell.

[0142] In some embodiments, the hardness of the first structure 2341 can be greater than the hardness of the second structure 2342. By providing two structures of different materials in the fusible portion 234 and making the hardness of the first structure 2341 greater than that of the second structure 2342, the overall mechanical strength of the fusible portion can be improved, as well as the manufacturability of the electrical connector can be improved, reducing the risk of bending or even breaking of the electrical connector during the production of battery cells.

[0143] In some embodiments, the melting point of the second structure 2342 may be lower than that of the first structure 2341. When a short circuit occurs outside the battery cell 20, a large instantaneous short-circuit current will appear on the electrical connector 23. The second structure 2342 in the fuse portion 234 will melt, thereby causing the overcurrent area of ​​the fuse portion 234 to decrease sharply and the resistance of the fuse portion 234 to increase. This causes the first structure 2341 to heat up more intensely, accelerating the melting of the first structure 2341, thereby cutting off the external current of the battery cell 20 and reducing the risk of battery cell failure.

[0144] The fusible link 234 can be located in any region of the body portion 233, as long as the current on the electrical connector 23 reaches the fusing threshold, the fusible link 234 can fuse, thereby disconnecting the first connection portion 231 and the second connection portion 232. In some embodiments, the fusible link 234 is located in the region of the body portion 233 with the smallest cross-sectional area along the thickness direction of the electrical connector 23, that is, the fusible link 234 can be located in any region of the body portion 233 with the smallest cross-sectional area along the thickness direction of the electrical connector 23.

[0145] For example, such as Figure 4 As shown, the fuse portion 234 is provided in the body portion 233 in a region near the first connecting portion 231, and this region has the smallest cross-sectional area along the thickness direction of the electrical connector 23.

[0146] For example, such as Figure 5 The schematic top view of the electrical connector according to an embodiment of this application shows that the fusible part 234 is provided in the body part 233 in a region near the second connecting part 232, and the cross-sectional area of ​​this region along the thickness direction of the electrical connector 23 is the smallest.

[0147] The region with the smallest cross-sectional area in the thickness direction of the electrical connector 23 is the region with the smallest area through which current flows on the electrical connector 23. This region has the highest impedance, and when a short-circuit current occurs on the electrical connector 23, this region will experience severe heating. By placing the fuse 234 in this region, when the current on the electrical connector is greater than or equal to a preset threshold, the fuse 234 can quickly melt and break the current between the first connection part 231 and the second connection part 232, thereby reducing the risk of battery cell failure due to the fuse not melting in time.

[0148] The following describes the specific configuration of the first structure 2341 and the second structure 2342 of the fuse section 234. For details, please refer to [link / reference needed]. Figures 6 to 8 The diagram shows several top views of the electrical connectors in the embodiments of this application along their thickness direction.

[0149] In some embodiments, the first structure 2341 and the second structure 2342 can be arranged sequentially along a first direction, that is, on a plane perpendicular to the thickness direction of the electrical connector 23, one end of the fuse portion 234 is the first structure 2341, and the other end is the second structure 2342. In some embodiments, the fuse portion 234 may include at least one first structure 2341 and at least one second structure 2342, and the arrangement of the at least one first structure 2341 and at least one second structure 2342 can be flexibly configured. For example, at least one first structure 2341 and at least one second structure 2342 can be arranged alternately along the first direction. Here, at least one first structure 2341 or at least one second structure 2342 can refer to one or more.

[0150] It should be understood that the first direction can be any direction. For example, the first direction can be the thickness direction. For another example, the first direction can also be perpendicular to the thickness direction of the electrical connector 23. That is, the first direction can be any direction on the plane perpendicular to the thickness direction of the electrical connector 23, and the first structure 2341 and the second structure 2342 can be arranged sequentially on the plane in a shape similar to a strip or in an arc.

[0151] In some embodiments, the first direction may be perpendicular to the thickness direction of the electrical connector 23, and at least one first structure 2341 and at least one second structure 2342 may also have their projections parallel to each other in the thickness direction of the electrical connector 23.

[0152] It should be understood that, on a plane perpendicular to the thickness direction of the electrical connector 23, the lengths of the first structure 2341 and the second structure 2342 in the direction perpendicular to the first direction may be less than or equal to the length of the fusible portion 234 in that direction.

[0153] For example, such as Figure 6 As shown, the first direction can be Figure 6 As shown in the X direction, multiple first structures 2341 and multiple second structures 2342 are arranged in parallel along the X direction, and the lengths of the first structures 2341 and second structures 2342 in the Y direction are equal to the length of the fuse portion 234 in the Y direction. For example, as... Figure 7 As shown, the first direction can be Figure 7 In the X direction shown, multiple second structures 2342 are arranged at intervals along the X direction. These second structures 2342 are located in the middle region of the fuse portion 234. The remaining regions of the fuse portion, excluding the second structures 2342, are all configured with first structures 2341, meaning the length of the first structure 2341 in the Y direction is less than the length of the fuse portion 234 in the Y direction. For example, as... Figure 8 As shown, the first direction can be as follows: Figure 8 As shown in the Y direction, multiple first structures 2341 and multiple second structures 2342 are arranged in parallel along the Y direction.

[0154] By alternating the first structure 2341 and the second structure 2342, and designing the fusible portion 234 as a mesh-like structure, the strength of the fusible portion 234 can be effectively increased, thereby improving the manufacturability and mechanical strength of the electrical connector 23 and reducing the risk of bending or even breakage of the electrical connector 23 during the production of the battery cell 20. By arranging the first structure 2341 and the second structure 2342 parallel to each other, when the current on the electrical connector reaches a certain preset threshold, the second structure 2342 quickly melts, causing the cross-sectional area of ​​the fusible portion 234 to decrease rapidly, thereby increasing the resistance in that area. The remaining first structure 2341 heats up more intensely, causing the first structure 2341 to also quickly melt, thereby cutting off the current on the electrical connector and reducing the risk of battery cell failure.

[0155] In some embodiments, the first structure 2341 and the second structure 2342 may also be arranged in other ways. For example, two of the first structures 2341 and one of the second structures 2342 may be arranged alternately in sequence. That is, the lengths of the first structure 2341 and the second structure 2342 along the first direction may be the same or different. For example, the length of the first structure 2341 along the first direction may be twice the length of the second structure along the first direction.

[0156] The arrangement between the first structure 2341 and the second structure 2342 can be further referenced. Figures 9 to 15 . Figure 9 This illustration shows another top view of the electrical connector according to an embodiment of the present application, for example, Figure 9 As shown Figure 4 Another top view of the electrical connector 23 along its thickness direction;

[0157] Figures 10 to 12 Several top view structural schematic diagrams of the fuse portion according to embodiments of this application are shown, for example, Figures 10 to 12 As shown Figure 4 Several top views of the fusion section 234 of the electrical connector 23 along its thickness direction are shown.

[0158] In some embodiments, the first direction may be perpendicular to the thickness direction of the electrical connector 23, and the projections of at least two adjacent second structures 2342 in the thickness direction of the electrical connector have an included angle.

[0159] It should be understood that there should be two or more second structures 2342 in the at least one second structure 2342, so that an included angle can be formed between two adjacent second structures 2342. The number and direction of the first structure 2341 and the second structure 2342 are not limited. The included angle formed by two adjacent second structures 2342 can be that the two second structures 2342 are connected at the included angle to form a "greater than" or "less than" sign, or the two second structures 2342 are not connected, similar to a trapezoid without two parallel sides.

[0160] In some embodiments, the projections of two adjacent second structures 2342 in at least one second structure 2342 in the thickness direction of the electrical connector have an included angle and are connected at the included angle.

[0161] Taking three first structures 2341 and two second structures 2342 as an example, the multiple first structures 2341 and multiple second structures 2342 along... Figure 9 When arranged sequentially along the X direction, the included angle between two adjacent second structures 2342 can be set at either end of the two second structures 2342 along the Y direction. For example, Figure 9 The diagram shows the included angle positioned at the left end of the fuse section 234. It can be understood that the included angle can also be positioned as follows: Figure 9 The position of the right end of the fuse section 234 is shown. The plurality of first structures 2341 and the plurality of second structures 2342 can also be along... Figure 10 When the Y-direction is set sequentially, the included angle between two adjacent second structures 2342 can be set at either end of the two second structures 2342 along the X-direction. For example, Figure 10 The included angle shown is set at the upper end of the fuse portion 234 along the X direction. The included angle can also be set at the lower end of the fuse portion 234 along the X direction.

[0162] It should be understood that the included angle between two adjacent second structures 2342 in the plurality of second structures 2342 can be located at the same end of the second structure 2342 or at different ends of the second structure 2342.

[0163] by Figure 11 and Figure 12 The example shown includes four first structures 2341 and three second structures 2342, as follows: Figure 11 As shown, the four first structures 2341 and three second structures 2342 are along Figure 11 The X-direction is alternately arranged sequentially, and the two adjacent second structures 2342 of the three second structures 2342 are all set at an angle at the same end along the Y-direction. It can be considered that the three second structures 2342 intersect at the same end in the Y-direction, and the three second structures 2342 diverge from the intersection to the other end. For example Figure 12 As shown, the four first structures 2341 and three second structures 2342 can also be configured such that the first and second second structures 2342 have an included angle a1 at one end along the Y direction, and the two second structures 2342 are connected at the included angle a1; while the second and third second structures 2342 have an included angle a2 at the other end along the Y direction, and the two second structures 2342 are connected at the included angle a2. The three second structures 2342 are connected sequentially at included angles a1 and a2, forming a shape similar to the capital letter "N".

[0164] With this design, the first structure 2341 and the second structure 2342 are intertwined. On the one hand, this can improve the connection strength of the fuse part 234 and reduce the risk of bending or breaking of the electrical connector. On the other hand, the second structure 2342, being a structure made of a low-melting-point material, forms a fast melting path in the fuse part 234. When there is an external short circuit in the battery cell, the fuse part 234 heats up intensely due to the instantaneous large current, which allows the second structure 2342 to melt quickly, thereby disconnecting the current on the electrical connector 23, reducing the risk of battery cell 20 failure, and improving the safety performance of the battery cell.

[0165] It should be understood that regardless of the arrangement of the first structure 2341 and the second structure 2342, the thickness of both structures can be less than or equal to the thickness of the fuse portion 234. For example, as Figure 13 As shown, Figure 13 It can be like Figure 7 The schematic diagram shows a cross-sectional view of the electrical connector 23 along the A-A' direction. The thickness of the second structure 2342 is equal to the thickness of the fusible portion 234. For example, as... Figure 14 As shown, Figure 14 Similarly, it can also be as follows: Figure 7 The schematic diagram of the cross-sectional structure of the electrical connector 23 along the A-A' direction shows that the thickness of the second structure 2342 is less than the thickness of the fuse portion 234.

[0166] The first structure 2341 and the second structure 2342 can also be arranged along the thickness direction of the electrical connector 23, such as... Figure 15 and 16 As shown. Figure 15 This illustration shows another top view of the electrical connector according to an embodiment of the present application, for example, Figure 15 As shown Figure 6 A top view of the electrical connector 23 along its thickness direction; Figure 16 This paper shows a cross-sectional structural schematic diagram of a fuse portion according to an embodiment of the present application, for example, Figure 16 As shown Figure 15A schematic diagram of a cross-sectional structure of the fusible part 234 in the electrical connector 23 along the B-B' direction.

[0167] In some embodiments, the first direction may be the thickness direction of the electrical connector 23. For example... Figure 15 and Figure 16 As shown, the fuse portion 234 includes at least one first structure 2341 and at least one second structure 2342, which are alternately arranged in sequence along the thickness direction of the electrical connector.

[0168] It should be understood that the first structure 2341 and the second structure 2342 can each be set as one and stacked along their thickness direction; or multiple first structures 2341 and multiple second structures 2342 can be set and alternately set along their thickness direction, or two or more first structures 2341 can be set continuously along their thickness direction, and then one or more second structures 2342 can be set continuously.

[0169] By arranging the first structure 2341 and the second structure 2342 along the thickness direction of the electrical connector, the electrical connector can have sufficient connection strength during battery cell production or normal use, reducing the risk of battery cell damage due to electrical connector deformation. When the current on the electrical connector reaches a certain preset threshold, the second structure 2342 melts rapidly, causing the cross-sectional area of ​​the melted part 234 to decrease rapidly, thereby increasing the resistance in that area. The remaining first structure 2341 heats up more intensely, causing the first structure 2341 to also melt rapidly, thereby cutting off the current on the electrical connector and reducing the risk of battery cell failure.

[0170] In some embodiments, the ratio of the volume of the first structure 2341 to the volume of the fuse portion 234 is [0.5, 0.8], that is, the volume ratio of the first structure 2341 should be greater than or equal to the volume ratio of the second structure. It can be understood that the ratio of the volume of the second structure 2342 to the volume of the fuse portion 234 is [0.2, 0.5], that is, for the first structure 2341 and the second structure 2342 constituting the fuse portion 234, the sum of the volume ratio of the first structure 2341 relative to the fuse portion 234 and the volume ratio of the second structure 2342 relative to the fuse portion 234 should be 1.

[0171] The first structure 2341 has higher hardness than the second structure 2342. The ratio of the volume of the first structure 2341 to the volume of the fuse part 234 is greater than 0.5, which can improve the structural strength of the fuse part and enhance the connection reliability of the electrical connector. The ratio of the volume of the first structure 2341 to the volume of the fuse part 234 is less than 0.8, that is, the volume ratio of the second structure 2342 should be greater than 0.2. In this way, when a short circuit current occurs on the electrical connector and reaches a preset threshold, the second structure 2342 can melt quickly due to its low melting point, so that only the first structure 2341 remains in the fuse part 234. The current-passing area of ​​the fuse part 234 is reduced and the impedance is increased, so that the first structure 2341 can also melt quickly, thereby cutting off the current on the electrical connector and reducing the risk of battery cell failure due to continuous heating caused by excessive current. By setting a higher volume ratio for the high-hardness first structure 2341, the electrical connector can have good connection strength, reduce the processing difficulty of the electrical connector, and reduce the risk of the electrode being crushed due to the deformation of the electrical connector. At the same time, the electrical connector can quickly disconnect when the current on the electrical connector is abnormally high, preventing the battery cell from failing and improving the safety performance of the battery cell.

[0172] In some embodiments, the ratio of the volume of the first structure 2341 to the volume of the fuse portion 234 can be any of the following values ​​or between any two of the following values: 0.5, 0.52, 0.54, 0.55, 0.57, 0.58, 0.6, 0.62, 0.64, 0.65, 0.67, 0.68, 0.7, 0.72, 0.74, 0.75, 0.77, 0.78, 0.8. The ratio of the volume of the second structure 2342 to the volume of the fuse part 234 can be any of the following values ​​or between any two of the following values: 0.2, 0.21, 0.23, 0.25, 0.26, 0.29, 0.3, 0.31, 0.33, 0.35, 0.36, 0.39, 0.4, 0.41, 0.43, 0.45, 0.46, 0.49, 0.5.

[0173] In some embodiments, the first structure 2341 can be integrally formed with the body 233, or it can be processed separately and connected by riveting or welding. The material of the first structure 2341 can be a conductive material with high hardness, such as aluminum or copper. In some embodiments, the electrical connector 23 is electrically connected to the positive electrode terminal 214a and the positive electrode tab 221a, and the first structure 2341 on the electrical connector 23 can be made of aluminum; the electrical connector 23 is electrically connected to the negative electrode terminal 214b and the negative electrode tab 221b, and the first structure 2341 on the electrical connector 23 can be made of copper. Both aluminum and copper have good conductivity and sufficient strength, which can improve the connection strength of the electrical connector and reduce the risk of damage to the battery cell due to deformation of the electrical connector.

[0174] In some embodiments, the material of the second structure 2342 can be tin, bismuth, lead, a tin-containing alloy, a bismuth-containing alloy, or a lead-containing alloy. That is, the second structure 2342 can be a tin component, a bismuth component, a lead component, a tin-containing alloy component, a bismuth-containing alloy component, or a lead-containing alloy component. A tin component refers to a conductive structural component made of tin. A bismuth component refers to a conductive structural component made of bismuth. A lead component refers to a conductive structural component made of lead. A tin-containing alloy component refers to a conductive structural component made of a mixture of tin and other materials. A bismuth-containing alloy component refers to a conductive structural component made of a mixture of bismuth and other materials. A lead-containing alloy component refers to a conductive structural component made of a mixture of lead and other materials.

[0175] Tin-containing alloy components may include conductive structural components made of alloy materials formed by tin and one or more of the following materials: materials that are mixed with tin to form alloys include: lithium, sodium, potassium, copper, silver, and gold of Group I; beryllium, magnesium, calcium, strontium, barium, zinc, cadmium, and mercury of Group II; aluminum, gallium, indium, thallium, ytterbium, lanthanum, and uranium of Group III; silicon, germanium, lead, titanium, zirconium, and hafnium of Group IV; phosphorus, arsenic, antimony, bismuth, vanadium, and niobium of Group V; selenium, tellurium, and chromium of Group VI; manganese of Group VII; and iron, cobalt, nickel, rhodium, palladium, and platinum of Group VIII.

[0176] Bismuth-containing alloys may include conductive structural components made of alloys formed by tin and one or more of the following materials: lithium, sodium, potassium, copper, silver, and gold from Group I; beryllium, magnesium, calcium, strontium, barium, zinc, cadmium, and mercury from Group II; aluminum, gallium, indium, thallium, ytterbium, lanthanum, and uranium from Group III; silicon, germanium, tin, lead, titanium, zirconium, and hafnium from Group IV; phosphorus, arsenic, antimony, vanadium, and niobium from Group V; selenium, tellurium, and chromium from Group VI; manganese from Group VII; and iron, cobalt, nickel, rhodium, palladium, and platinum from Group VIII.

[0177] Lead-containing alloy parts may include conductive structural parts made of alloy materials formed by lead with one or more of the following materials: lithium, sodium, potassium, copper, silver, and gold from Group I; beryllium, magnesium, calcium, strontium, barium, zinc, cadmium, and mercury from Group II; aluminum, gallium, indium, thallium, ytterbium, lanthanum, and uranium from Group III; silicon, germanium, tin, lead, titanium, zirconium, and hafnium from Group IV; phosphorus, arsenic, antimony, vanadium, and niobium from Group V; selenium, tellurium, and chromium from Group VI; manganese from Group VII; and iron, cobalt, nickel, rhodium, palladium, and platinum from Group VIII.

[0178] The second structure 2342 uses tin, bismuth, lead, tin alloy, bismuth alloy, or lead alloy components. It not only has good electrical conductivity but also allows the melting temperature of the fuse 234 to be low. When a short circuit occurs outside the battery cell, the instantaneous large short-circuit current passes through the fuse 234 and generates intense heat, enabling the second structure to melt quickly and thus providing good fuse protection for the battery cell 20.

[0179] In the fusing test of the fusible portion 234, the cross-sectional area of ​​the fusible portion 234 along its thickness direction was 16 mm. 2 For example, the first structure is made of aluminum, and the second structure is made of a lead-bismuth alloy, wherein the mass percentage of lead is [40%, 50%], and the mass percentage of bismuth is [50%, 60%]. For different shapes and arrangements of the first structure 2341 and the second structure 2342 (using... Figure 6 , Figure 9 , Figure 15 Taking [example] as an example, and considering the different volume ratios between the first and second structures, the fusing time (s) of the fusing part 234, the droop height (mm) of the electrical connector after welding the end cap 212 of the battery cell 20, and the opening status of the pressure relief mechanism 213 when the battery cell 20 is externally short-circuited in the new national standard (hereinafter referred to as the valve opening status) were tested, and the test results are shown in Table 1 below. It should be understood that the droop height of the electrical connector refers to the deformation thickness of the electrical connector along its thickness direction.

[0180] Table 1

[0181]

[0182]

[0183] In some embodiments, the first structure 2341 and the second structure 2342 can be connected by riveting or welding. For example, Figure 17 As shown, Figure 17 This paper shows another cross-sectional structural schematic diagram of the fuse portion according to an embodiment of the present application, for example, Figure 17 As shown Figure 15The diagram shows another cross-sectional view of the fusion section 234 of the electrical connector 23 along the B-B' direction. When the first structure 2341 and the second structure 2342 are connected by welding, a low-melting-point metal welding rod can be used. High temperature melts the connecting portion between the first structure 2341 and the second structure 2342, forming an alloy layer 234a. Finally, cooling and solidification achieve the connection between the first structure 2341 and the second structure 2342. The solder can be tin-lead solder or eutectic solder, etc. Welding creates an alloy layer 234a between the first structure 2341 and the second structure 2342, which has good mechanical properties and load-bearing capacity, effectively improving the connection strength between them. Riveting allows for a tight connection between the first structure 2341 and the second structure 2342, and the stress distribution during riveting is uniform, further improving the strength and rigidity of the fusion section 234.

[0184] According to some embodiments of this application, this application also provides an electrical connector 23, which may include: a first connecting portion 231, a second connecting portion 232, and a body portion 233; the first connecting portion 231 is used for electrical connection with the electrode terminal 214 of the battery cell 20, the second connecting portion 232 is used for electrical connection with the tab 221 of the battery cell 20, and the body portion 233 is used for electrical connection between the first connecting portion 231 and the second connecting portion 232, wherein the body portion 233 has a first structure 2341 and a second structure 2342, and the first structure 2341 and the second structure 2342 have different strengths.

[0185] In some embodiments, the body portion 233 is provided with a fuse portion 234, which is configured to melt when the current on the electrical connector 23 is greater than or equal to a preset threshold, thereby disconnecting the first connection portion 231 and the second connection portion 232; wherein, the fuse portion 234 includes a first structure 2341 and a second structure 2342, and the first structure 2341 and the second structure 2342 are made of different materials.

[0186] According to some embodiments of this application, this application also provides a battery device including a plurality of battery cells described in any of the above embodiments.

[0187] According to some embodiments of this application, this application also provides an electrical device, including multiple battery cells or multiple battery devices as described in any of the above embodiments, wherein the battery cells or battery devices are used to provide or store electrical energy.

[0188] According to some embodiments of this application, this application also provides an energy storage system, such as... Figure 18As shown, the energy storage system 1 may include one or more energy storage devices 2 and a power conversion device 3 (PowerConverter System, or PCS). The power conversion device 3 is used to connect the power generation device 4 and the energy storage device 2. The power generation device 4 is used to generate electrical energy, and the electrical energy generated by the power generation device 4 can be stored in the energy storage device 2 through the power conversion device 3. As an example, the power generation device 4 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 4 is not limited in this application.

[0189] According to some embodiments of this application, this application also provides a charging network, including a charging pile and an energy storage device as described in any of the above embodiments, wherein the energy storage device is used to provide electrical energy to the charging pile.

[0190] like Figure 19 As shown in the illustration, this application provides a charging network 5, including a charging pile 6 and an energy storage device 2. The charging pile 6 is electrically connected to the energy storage device 2, which provides electrical energy to the charging pile 6. The charging pile 6 is electrically connected to a battery device in the energy storage device 2 via a cable, and the battery device can provide its stored electrical energy to the charging pile 6. The charging pile 6 has one or more connectors 7 for connecting to electrical equipment (such as a vehicle), thereby enabling the charging equipment to receive additional power.

[0191] The energy storage device 2 can be located inside the charging pile 6 (e.g., an integrated energy storage and charging unit) or outside the charging pile 6.

[0192] According to some embodiments of this application, see Figure 9 This application provides a battery cell 20, including: an electrode terminal 214; an electrode assembly 22 having a tab 221; and an electrical connector 23 including a first connecting portion 231, a second connecting portion 232, and a body portion 233; the first connecting portion 231 is used to electrically connect to the electrode terminal 214, the second connecting portion 232 is used to electrically connect to the tab 221, and the body portion 233 is used to electrically connect the first connecting portion 231 and the second connecting portion 232; the body portion 233 has a first structure 2341 and a second structure 2342, the first structure 2341 and the second structure 2342 having different strengths.

[0193] The main body 233 is provided with a fuse part 234, which is configured to melt when the current on the electrical connector 23 is greater than or equal to a preset threshold, thereby disconnecting the first connection part 231 and the second connection part 232; wherein, the fuse part 234 includes the first structure 2341 and the second structure 2342, and the first structure 2341 and the second structure 2342 are made of different materials.

[0194] The fuse portion 234 is located in the area with the smallest cross-sectional area in the body portion 233 along the thickness direction of the electrical connector 23.

[0195] The hardness of the first structure 2341 is greater than that of the second structure 2342; the melting point of the second structure 2342 is less than that of the first structure 2341.

[0196] The fuse portion 234 includes at least one first structure 2341 and at least one second structure 2342, which are alternately arranged in sequence along a first direction.

[0197] The first direction is perpendicular to the thickness direction of the electrical connector 23, and the projections of two adjacent second structures 2342 in the thickness direction of the electrical connector have an included angle.

[0198] The ratio of the volume of the first structure 2341 to the volume of the fuse portion 234 is [0.5, 0.8].

[0199] The material of the first structure 2341 includes aluminum or copper; the material of the second structure 2342 is tin, bismuth, lead, tin-containing alloy, bismuth-containing alloy, or lead-containing alloy.

[0200] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and not to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. These modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application, and they should all be covered within the scope of the claims and specification of this application. In particular, as long as there is no structural conflict, the various technical features mentioned in the embodiments can be combined in any way. 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 in that, include: Electrode terminal (214); Electrode assembly (22), said electrode assembly (22) having tabs (221); An electrical connector (23) includes a first connecting part (231), a second connecting part (232), and a body part (233). The first connecting part (231) is used to electrically connect with the electrode terminal (214), the second connecting part (232) is used to electrically connect with the tab (221), and the body part (233) is used to electrically connect the first connecting part (231) and the second connecting part (232). The main body (233) has a first structure (2341) and a second structure (2342), and the first structure (2341) and the second structure (2342) have different strengths.

2. The battery cell according to claim 1, characterized in that, The main body (233) is provided with a fuse (234), which is configured to melt when the current of the electrical connector (23) is greater than or equal to a preset threshold, thereby disconnecting the first connection (231) and the second connection (232). The fused portion (234) includes the first structure (2341) and the second structure (2342), and the first structure (2341) and the second structure (2342) are made of different materials.

3. The battery cell according to claim 2, characterized in that, The fused portion (234) is located in the area with the smallest cross-sectional area in the body portion (233) along the thickness direction of the electrical connector (23).

4. The battery cell according to claim 2, characterized in that, The hardness of the first structure (2341) is greater than that of the second structure (2342).

5. The battery cell according to claim 2, characterized in that, The melting point of the second structure (2342) is lower than that of the first structure (2341).

6. The battery cell according to any one of claims 2 to 5, characterized in that, The fuse portion (234) includes at least one first structure (2341) and at least one second structure (2342), and at least one first structure (2341) and at least one second structure (2342) are alternately arranged in sequence along a first direction.

7. The battery cell according to claim 6, characterized in that, The first direction is perpendicular to the thickness direction of the electrical connector (23), and the projections of the at least one first structure (2341) and the at least one second structure (2342) in the thickness direction of the electrical connector (23) are parallel to each other.

8. The battery cell according to claim 6, characterized in that, The first direction is perpendicular to the thickness direction of the electrical connector (23), and the projections of two adjacent second structures (2342) in the thickness direction of the electrical connector (23) have an angle.

9. The battery cell according to claim 6, characterized in that, The first direction is the thickness direction of the electrical connector (23).

10. The battery cell according to any one of claims 2 to 5, characterized in that, The ratio of the volume of the first structure (2341) to the volume of the fuse (234) is [0.5, 0.8].

11. The battery cell according to any one of claims 2 to 5, characterized in that, The material of the first structure (2341) includes aluminum or copper.

12. The battery cell according to claim 11, characterized in that, The material of the second structure (2342) is tin, bismuth, lead, tin-containing alloy, bismuth-containing alloy or lead-containing alloy.

13. A battery device, characterized in that, It includes multiple battery cells according to any one of claims 1 to 12.

14. An electrical appliance, characterized in that, It includes a plurality of battery cells according to any one of claims 1 to 12 or a plurality of battery devices according to claim 13, wherein the battery cells or the battery devices are used to provide or store electrical energy.

15. A charging network, characterized in that, It includes a charging pile and an electrical device according to claim 14, wherein the electrical device is used to provide electrical energy to the charging pile.

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