Battery device and electric device

Abstract

A battery device and a power utilization device belong to the technical field of batteries. The battery device comprises a connecting piece and a wire bundle, the connecting piece comprises a first part and a second part which are connected, the yield strength of the second part and the yield strength of the wire bundle are both smaller than the yield strength of the first part, and the wire bundle is connected with the second part. In the battery device, the lead bundle and the second part can absorb the mechanical stress of the battery under the working condition of long-term vibration or thermal cycle, so that the stress borne by the first part can be reduced, and the connection stability of the first part and the connection end connected with the first part can be improved; the second part and the wire bundle cooperatively deform, thereby facilitating the improvement of the connection stability of the two parts.

Description

Technical Field

[0001] The utility model relates to the technical field of batteries, and in particular to a battery device and an electrical device. Background Art

[0002] In the field of new energy batteries, battery devices usually include several battery cells. The output pole of the battery cell is connected to the high-voltage copper bar through a connector. The connector and the high-voltage copper bar are both made of hard materials. After the two are connected using a connection method such as bolt locking, under long-term vibration conditions, the connector and the high-voltage copper bar lack a stress-absorbing structure, and the contact surface between the connector and the high-voltage copper bar is prone to micro-wear, increasing contact resistance and even causing local overheating or connection failure. Utility Model Content

[0003] The present application aims to solve at least one of the technical problems existing in the prior art. To this end, one object of the present application is to provide a battery device comprising a connection structure that can absorb mechanical stress under conditions of long-term battery vibration or thermal cycling, thereby improving the connection stability of the connection structure and the connection ends connected to the connection structure, reducing the risk of fatigue failure caused by direct connection of hard materials, improving connection reliability, and reducing the possibility of thermal failure.

[0004] The present application also provides an electrical device.

[0005] In a first aspect, an embodiment of the present invention provides a battery device, which includes a connection structure, the connection structure includes a connector and a wire bundle, the connector includes a first part and a second part connected to each other, the yield strength of the second part and the yield strength of the wire bundle are both smaller than the yield strength of the first part, and the wire bundle is connected to the second part.

[0006] In the above technical solution, the first part is used to connect to the connection end. The yield strength of the first part is greater than the yield strength of the second part and the yield strength of the wire bundle. The first part is less likely to deform than the second part and the wire bundle. The wire bundle and the second part can absorb the mechanical stress under the working conditions of long-term vibration or thermal cycling of the battery device, which is beneficial to reducing the stress on the first part and improving the connection stability of the first part and the connection end connected to the first part. The second part and the wire bundle deform in coordination, which is beneficial to improving the connection stability of the two. The connection between the connector and the wire bundle is less likely to have problems such as cracks, breakage, and separation. Therefore, the connection structure in the embodiment of the present application is beneficial to reducing the risk of fatigue failure caused by direct connection of hard materials, improving connection reliability, and reducing the possibility of thermal failure.

[0007] In some embodiments, the hardness of the material of the second portion is less than the hardness of the material of the first portion.

[0008] In the above technical solution, the hardness of the material of the second part is less than that of the material of the first part. When the wire harness is deformed, the second part will also deform to a certain extent. In this way, fatigue fracture is not likely to occur at the connection position between the wire harness and the connector, which is conducive to extending the service life.

[0009] In some embodiments, the second portion comprises a plurality of foils arranged in a stacked manner, and edges of the plurality of foils are connected to the first portion.

[0010] In this technical solution, the multi-layered foil structure is flexible, which helps to increase the contact area between the wire bundle and evenly distribute the current, reduce local current density, and minimize the risk of overheating. At the same time, the performance of the connector is consistent.

[0011] In some embodiments, the second portion is connected to the wire bundle along a side surface in the foil stacking direction.

[0012] In the above technical solution, when connecting, the wire bundle is directly placed on the side surface of the second part along the foil stacking direction, and then welded or conductively bonded, which is conducive to improving the convenience of the connection operation.

[0013] In some embodiments, the wire bundle includes a plurality of wires, at least some of which are disposed between the two foils and connected to the foils.

[0014] In the above technical solution, the connection area between the wire and the foil is large, so as to enable as many wires as possible to be directly connected to the foil, which is conducive to heat distribution and reducing local high-temperature points; the multi-layer stacked foil has good flexibility and can better cover the wire bundle, thereby making the connection area between the wire bundle and the foil larger.

[0015] In some embodiments, any two adjacent layers of the foils are connected to each other.

[0016] In the above technical solution, the multi-layer foil can be restored to a stacked state to facilitate subsequent welding or bonding with the wire bundle. At the same time, the flow area at the multi-layer foil is large and the flow performance is good.

[0017] In some embodiments, the first portion includes a main body portion and a transition portion, wherein the transition portion is connected between the main body portion and the second portion;

[0018] The transition portion includes a first section and a second section, and the main body, the first section, the second section and the second part are connected in sequence. The hardness of the first section is less than the hardness of the main body, the hardness of the first section is greater than the hardness of the second section, and the hardness of the second section is greater than the hardness of the second part.

[0019] In the above technical solution, the main body and the second part are connected by a transition section. This section mitigates the sudden change in stiffness that occurs when the main body and the second part are directly connected, reduces stress concentration at the connection, alleviates thermal and mechanical stresses, reduces the risk of cracking, and extends service life. The second part absorbs energy, while the main body maintains strength. Combined with the transition section, this allows for a coordinated response under dynamic loads, improving the connector's vibration resistance.

[0020] In some embodiments, along a first direction, the main body, the transition portion and the second portion are arranged in sequence, and the main body and the second portion are staggered, and the first direction is perpendicular to the thickness direction of the second portion.

[0021] In the above technical solution, the main body and the second part are staggered. When the connecting part is subjected to stress along the first direction, the direct extrusion or impact of the second part on the first part can be reduced, and part of the stress is absorbed by the deformation of the transition part, thereby reducing the risk of damage to the main body.

[0022] In some embodiments, the hardness of the transition portion gradually decreases along a direction from the main body to the second portion.

[0023] In the above technical solution, the load transfer between the main body and the second part can be further made more natural, local overload can be avoided, the load-bearing efficiency of the overall structure can be improved, the degree of hardness mutation at the interface can be reduced, and the risk of cracks can be reduced.

[0024] In some embodiments, the transition portion includes a first metal layer and a second metal layer connected to each other, the hardness of the material of the first metal layer is greater than the hardness of the material of the second metal layer, and the ratio of the thickness of the first metal layer to the thickness of the second metal layer gradually decreases along the direction from the main body to the second part.

[0025] In the above technical solution, by changing the thickness ratio between the first metal layer and the second metal layer, the transition part has a gradually decreasing hardness along the direction from the main body to the second part. In this way, the range of the hardness gradient of the transition part can be flexibly controlled.

[0026] In some embodiments, the main body is a copper alloy part; and / or the main body is a flat plate part.

[0027] In the above technical solution, the main body has a higher structural strength, and has better connection stability when welded or bolted to the connection end, higher connection strength, and better connection stability.

[0028] In some embodiments, the second portion is welded to the wire harness; and / or the battery device includes a battery cell, the battery cell includes a terminal, and the first portion is welded to the terminal.

[0029] In the above technical solution, the second part is welded to the wire harness. This ensures stable contact resistance between the second part and the wire harness, making it less susceptible to oxidation, contamination, or loosening, and resulting in a long service life. Furthermore, the second part's low hardness and good flexibility match the melting point of the wire harness, resulting in better welding compatibility. The weld creates a metallurgical bond without the risk of loosening, and exhibits significantly better resistance to vibration and thermal cycling than bolted connections. The first part is high in strength and welded to the pole, ensuring a stable connection between the pole and the connector.

[0030] In a second aspect, an embodiment of the present invention further provides an electrical device, comprising the above-mentioned battery device, wherein the battery device is used to provide electrical energy to the electrical device.

[0031] In the above technical solution, the battery device has good structural stability, which can ensure the performance and safety of the battery device, thereby enabling the electrical device equipped with the battery device to have good performance and safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 A schematic structural diagram of a vehicle provided in some embodiments of the present application;

[0033] Figure 2 An exploded view of a battery device provided in some embodiments of the present application;

[0034] Figure 3 A schematic diagram of a connection structure provided in some embodiments of the present application;

[0035] Figure 4 A schematic diagram of a connection structure provided in some other embodiments of the present application;

[0036] Figure 5 A schematic structural diagram of a connecting member in a connection structure provided in some other embodiments of the present application;

[0037] Figure 6 A side view of a connecting member in a connecting structure provided in some other embodiments of the present application;

[0038] Figure 7 This is a schematic structural diagram of the transition portion in the connection structure provided in some embodiments of the present application.

[0039] Reference numerals:

[0040] Vehicles 1000;

[0041] Battery device 100; controller 200; motor 300;

[0042] Box 30;

[0043] First box 301; second box 302;

[0044] Battery cell 20;

[0045] Connecting structure 10;

[0046] Connector 101; first portion 1011; second portion 1012; foil 1013;

[0047] Main body 1014; transition portion 1015; first section 1016; second section 1017;

[0048] First metal layer 1018 ; second metal layer 1019 ; wire bundle 102 ; wire 1021 . DETAILED DESCRIPTION

[0049] To make the purpose, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the embodiments described are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0050] Unless otherwise defined, all technical and scientific terms used in this utility model have the same meanings as those commonly understood by those skilled in the art to which this utility model belongs; the terms used in the specification of this utility model are only for the purpose of describing specific embodiments and are not intended to limit this utility model; the terms "including" and "having" and any variations thereof in the specification and claims of this utility model and the above-mentioned drawings are intended to cover non-exclusive inclusions. The terms "first", "second", etc. in the specification and claims of this utility model or the above-mentioned drawings are used to distinguish different objects, rather than to describe a specific order or a primary-secondary relationship.

[0051] Reference to an "embodiment" in this disclosure means that a particular feature, structure, or characteristic described in connection with the embodiment may be included in at least one embodiment of the disclosure. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it constitute an independent or alternative embodiment that is mutually exclusive of other embodiments.

[0052] In the description of this utility model, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," "connected," and "attached" should be understood in a broad sense. For example, they may refer to fixed connections, detachable connections, or integral connections; they may refer to direct connections, indirect connections through an intermediate medium, or internal communication between two components. Those skilled in the art will understand the specific meanings of these terms in this utility model based on specific circumstances.

[0053] In this application, the term "and / or" simply describes a relationship between related objects, indicating that three possible relationships exist. For example, "A and / or B" can represent: A exists alone, A and B exist simultaneously, and B exists alone. Furthermore, the character " / " in this application generally indicates that the related objects are in an "or" relationship.

[0054] In the embodiments of the present invention, the same reference numerals represent the same components, and for the sake of brevity, detailed descriptions of the same components in different embodiments are omitted. It should be understood that the thickness, length, width, and other dimensions of the various components in the embodiments of the present invention, as well as the overall thickness, length, width, and other dimensions of the integrated device shown in the drawings are for illustrative purposes only and do not constitute any limitation on the present invention.

[0055] The term “plurality” used in this invention refers to more than two (including two).

[0056] The battery apparatus mentioned in the embodiments of the present application may include one or more battery cell assemblies for providing voltage and capacity. The battery cell assembly may include multiple battery cells, which are connected in series, parallel, or hybrid via a busbar.

[0057] In some embodiments, a battery cell assembly is generally formed by arranging a plurality of battery cells.

[0058] As an example, the battery cell assembly may be a battery module, which is formed by arranging and fixing multiple battery cells to form an independent module. As an example, the battery module may be formed by bundling multiple battery cells with a cable tie.

[0059] In some embodiments, the battery device may be a battery pack, which includes a case and one or more battery cell assemblies, wherein the battery cell assemblies are housed in the case.

[0060] As an example, the battery cell assembly may be a battery module, and the battery cell assembly may be accommodated in the box by fixing the battery module in the box.

[0061] As an example, the battery cell assembly may also be housed in the box by directly fixing the plurality of battery cells to the box.

[0062] As an example, the housing may include a first housing and a second housing. The first housing and the second housing engage to form an enclosed space within the housing to house the battery cell assembly. Enclosed here means covered or closed, and can be either sealed or unsealed. The first housing may be a top cover or a bottom plate.

[0063] As an example, the box may include a top cover, a frame, and a bottom plate, wherein the top cover and the bottom plate are respectively connected to the frame to form a closed space inside the box to accommodate the battery cell assembly.

[0064] In some embodiments, the box body can be used as a part of the chassis structure of the vehicle. For example, part of the box body can become at least a part of the floor of the vehicle, or part of the box body can become at least a part of the cross beam and longitudinal beam of the vehicle.

[0065] In this application, battery cells may include lithium-ion secondary batteries, lithium-ion primary batteries, lithium-sulfur batteries, sodium-lithium-ion batteries, sodium-ion batteries, magnesium-ion batteries, or solid-state batteries, etc., and the embodiments of this application are not limited to this. Battery cells may be cylindrical, rectangular, or in other shapes, etc., and the embodiments of this application are not limited to this.

[0066] In some embodiments, a battery cell includes a housing, an electrode assembly, an electrolyte (which in a solid-state battery may be a solid electrolyte layer located between the positive and negative electrode sheets), a positive electrode column, and a negative electrode column. At least one electrode assembly is provided, and both the electrode assembly and the electrolyte are housed in the housing. The electrode assembly includes a positive electrode sheet, a negative electrode sheet, and a separator (this structure may be omitted in a solid-state battery). The electrode assembly is electrically connected to the positive and negative electrode columns, with portions of the positive and negative electrode columns exposed outside the housing to electrically connect the battery cell to an external device. The battery cell primarily operates by the movement of metal ions between the positive and negative electrode sheets.

[0067] In some embodiments, the positive electrode tab includes a positive electrode current collector and a positive electrode active material layer. The positive electrode active material layer is coated on the surface of the positive electrode current collector. The positive electrode current collector not coated with the positive electrode active material layer protrudes from the positive electrode current collector coated with the positive electrode active material layer. The positive electrode current collector not coated with the positive electrode active material layer serves as the positive electrode tab. For lithium-ion batteries as an example, the positive electrode current collector can be made of aluminum, and the positive electrode active material can be lithium cobalt oxide, lithium iron phosphate, ternary lithium, or lithium manganese oxide, among others.

[0068] In some embodiments, the negative electrode sheet includes a negative electrode current collector and a negative electrode active material layer. The negative electrode active material layer is coated on the surface of the negative electrode current collector. The negative electrode current collector not coated with the negative electrode active material layer protrudes from the negative electrode current collector coated with the negative electrode active material layer. The negative electrode current collector not coated with the negative electrode active material layer serves as the negative electrode tab. The negative electrode current collector can be made of copper, and the negative electrode active material can be carbon, silicon, or the like.

[0069] In some embodiments, the isolation film may be made of polypropylene (PP) or polyethylene (PE).

[0070] In some embodiments, the electrode assembly can be a wound or laminated structure. During processing, the positive electrode sheet, negative electrode sheet, and separator are sequentially wound or laminated to obtain the electrode assembly. In the electrode assembly, multiple positive electrode tabs are stacked together and electrically connected to the positive electrode post, and multiple negative electrode tabs are stacked together and electrically connected to the negative electrode post.

[0071] Currently, market developments indicate that batteries are becoming increasingly widely used. Batteries are not only used in energy storage systems such as hydropower, thermal, wind, and solar power plants, but are also widely used in electric vehicles like electric bicycles, electric motorcycles, and electric cars, as well as in military equipment and aerospace. As the application of power batteries continues to expand, market demand is also growing.

[0072] In the field of new energy battery packs, battery devices usually include several battery cells. The output pole of the battery cell is connected to the high-voltage copper bar through a connector. The connector and the high-voltage copper bar are both made of hard materials. After the two are connected using a connection method such as bolt locking, under long-term vibration conditions, the connector and the high-voltage copper bar lack a stress-absorbing structure. The contact surface between the connector and the high-voltage copper bar is prone to micro-wear, which increases contact resistance and even causes local overheating or connection failure.

[0073] Based on this, the present application proposes a battery device, which includes a connection structure, the connection structure includes a connector and a wire bundle, the connector includes a first part and a second part that are connected, the yield strength of the second part and the yield strength of the wire bundle are both smaller than the yield strength of the first part, and the wire bundle is connected to the second part.

[0074] In the battery device of the above-mentioned structure, the first part is used to connect to a certain connection terminal in the battery device. The yield strength of the first part is greater than the yield strength of the second part and the yield strength of the wire bundle. The first part is less likely to deform than the second part. The wire bundle and the second part can absorb the mechanical stress of the battery device under vibration or thermal cycling conditions, which is beneficial to reducing the stress on the first part and improving the connection stability of the first part and the connection terminal connected to the first part. The second part and the wire bundle deform in coordination, which is beneficial to improving the connection stability of the two. The connection between the connector and the wire bundle is less likely to crack, break, separate, and other problems. Therefore, the connection structure in the embodiment of the present application is beneficial to reducing the risk of fatigue failure caused by direct connection of hard materials, improving connection reliability, and reducing the possibility of thermal failure.

[0075] The technical solutions described in the embodiments of the present application are applicable to battery devices and electrical devices using battery devices.

[0076] Electrical devices can include vehicles, mobile phones, portable devices, laptops, ships, spacecraft, electric toys, power tools, and energy storage devices. Vehicles can be fuel-powered, gas-powered, or new energy vehicles. New energy vehicles can include pure electric vehicles, hybrid vehicles, or extended-range vehicles. Spacecraft include aircraft, rockets, space shuttles, and spacecraft. Electric toys include fixed or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys. Power tools include metal cutting, grinding, assembly, and railway tools, such as electric drills, electric grinders, electric wrenches, electric screwdrivers, electric hammers, impact drills, concrete vibrators, and electric planers. 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 release it at the appropriate time. For example, energy storage devices can store energy during low-consumption periods and provide it to relevant users or electrical equipment during peak demand periods. The embodiments of the present application do not impose any special restrictions on the specific type of the electrical device.

[0077] For the convenience of description, the following embodiments are described by taking a vehicle as an example of an electrical device.

[0078] Please refer to Figure 1 , Figure 1 This is a schematic diagram of the structure of a vehicle 1000 provided in some embodiments of the present application. The vehicle 1000 is provided with a battery device 100. The battery device 100 can be installed at a location such as the bottom, head, or tail of the vehicle 1000. The battery device 100 can be used to power the vehicle 1000. For example, the battery device 100 can serve as the operating power source of the vehicle 1000.

[0079] The vehicle 1000 may further include a controller 200 and a motor 300 . The controller 200 is used to control the battery device 100 to supply power to the motor 300 , for example, to meet the power requirements of the vehicle 1000 during startup, navigation, and driving.

[0080] In some embodiments of the present application, the battery device 100 can not only serve as the operating power source of the vehicle 1000, but also serve as the driving power source of the vehicle 1000, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1000.

[0081] Please refer to Figure 2 , Figure 2 This is an exploded view of a battery device 100 provided in some embodiments of the present application, wherein the battery device 100 includes a battery cell 20 and a box 30 for accommodating the battery cell 20. The box 30 can have various structural forms.

[0082] In some embodiments, the box 30 may include a first box 301 and a second box 302, which cover each other and define a storage space for accommodating the battery cells 20. A seal may be provided at the connection between the first box 301 and the second box 302 to achieve a sealed connection between the first box 301 and the second box 302. For example, referring to Figure 2 The first box 301 and the second box 302 can both be hollow structures with one side open. The open side of the first box 301 covers the open side of the second box 302, thereby forming the box 30 with a storage space. For another example, the second box 302 can be a hollow structure with one side open, and the first box 301 is in the form of a cover that can cover the open side of the second box 302. The box 30 can have various shapes, such as a cylindrical box, a rectangular box, etc.

[0083] Please refer to Figure 3 , Figure 3 This is a schematic structural diagram of the connection structure 10 provided in some embodiments of the present application. Figure 4 Schematic diagram of the structure of the connection structure 10 provided in some other embodiments of the present application.

[0084] like Figure 3 and Figure 4 As shown, the battery device 100 according to an embodiment of the present application includes a connection structure 10, the connection structure 10 includes a connector 101 and a wire bundle 102, the connector 101 includes a first part 1011 and a second part 1012 connected to each other, the yield strength of the second part 1012 and the yield strength of the wire bundle 102 are both less than the yield strength of the first part 1011, and the wire bundle 102 is connected to the second part 1012.

[0085] Exemplarily, the connection structure 10 can be used to connect two battery modules. The connection structure 10 includes two connectors 101. The first parts 1011 of the two connectors 101 are respectively connected to the poles of the two battery modules, and the second parts 1012 of the two connectors 101 are respectively connected to the two ends of the wire bundle 102.

[0086] Exemplarily, the connection structure 10 can be used to connect two battery cells 20. The connection structure 10 includes two connectors 101. The first parts 1011 of the two connectors 101 are respectively connected to the poles of the two battery cells 20, and the second parts 1012 of the two connectors 101 are respectively connected to the two ends of the wire harness 102.

[0087] For example, the first portion 1011 of the connector 101 can be used to connect to a busbar, and the end of the wire harness 102 not connected to the second portion 1012 can be used to connect to a high-voltage box, a charging port, or a connector. The high-voltage box is used to control the electrical signals and drive the entire battery device 100 on and off, and the connector is used to connect the inside and outside of the battery device 100 to transmit current and signals. In addition, the connection structure 10 can also be used to connect a flexible circuit inside the battery device 100 to a rigid connection end, that is, the other end of the wire harness 102 not connected to the second portion 1012 is connected to the flexible circuit.

[0088] It should be noted that the yield strength refers to the stress value when the specimen begins to produce significant plastic deformation during the stress process.

[0089] Exemplarily, the wire bundle 102 may include only one wire 1021 and an insulating layer wrapped around the wire 1021; alternatively, the guide bundle may include multiple wires 1021 and an insulating layer wrapped around the multiple wires 1021; alternatively, the wire bundle 102 may include multiple wires 1021, all of which are wrapped with insulating layers, and the multiple wires 1021 with insulating layers are assembled into a bundle; alternatively, the wire bundle 102 may include multiple wires 1021, all of which are wrapped with insulating layers, and all of the wires 1021 with insulating layers may be further wrapped in an outer insulating layer.

[0090] For example, the wire bundle 102 can have a lower yield strength by using a metal with relatively low hardness and good flexibility to form the wires 1021 in the guide bundle 102, and a plastic with relatively low hardness and good flexibility to form the insulation layer of the wire bundle 102. For example, the wire bundle 102 can have a lower yield strength by using wires 1021 with relatively small outer diameters to form the guide bundle 102.

[0091] The first portion 1011 is used to connect to a connection terminal in the battery device 100. The yield strength of the first portion 1011 is greater than the yield strength of the second portion 1012 and the yield strength of the wire harness 102. The first portion 1011 is less susceptible to deformation than the second portion 1012. The wire harness 102 and the second portion 1012 can absorb the mechanical stress under conditions of long-term vibration or thermal cycling of the battery device 100, which helps to reduce the stress on the first portion 1011 and improve the connection stability of the first portion 1011 and the connection terminal connected to the first portion 1011.

[0092] The coordinated deformation of the second portion 1012 and the wire bundle 102 helps improve the stability of the connection between the two, and the connection between the connector 101 and the wire bundle 102 is less likely to crack, break, or separate. Therefore, the connection structure 10 in the embodiment of the present application helps reduce the risk of fatigue failure caused by direct connection of hard materials, improves connection reliability, and reduces the possibility of thermal failure.

[0093] In some embodiments, the connection end connected to the first part 1011 is a rigid connection end, and the first part 1011 is welded to the rigid connection end. The yield strength of the first part 1011 is greater than the yield strength of the second part 1012, and the hardness of the first part 1011 is generally greater than the hardness of the second part 1012. Welding the first part 1011 to the rigid connection end is beneficial to improving the welding quality, thereby improving the connection stability between the first part 1011 and the rigid connection end.

[0094] In some embodiments, the rigid connection end is a terminal of the battery cell 20 .

[0095] In some embodiments, the hardness of the material of the second portion 1012 is less than the hardness of the material of the first portion 1011 , thereby making the yield strength of the second portion 1012 less than the yield strength of the first portion 1011 .

[0096] The hardness and yield strength of a material are usually positively correlated, and in the process of selecting and preparing materials, it is often more convenient to select or control based on hardness. Therefore, by selecting materials of different hardness or adopting different processing techniques to make different parts of the same material have different hardness, the purpose of making the yield strength of the first part 1011 and the second part 1012 different is achieved.

[0097] Exemplarily, the first part 1011 is made of a conductive metal material with greater hardness, such as brass, copper, or nickel-plated copper, and the second part 1012 is made of a conductive metal material with less hardness, such as gold, silver, or tin-plated copper.

[0098] For example, along the direction from the first portion 1011 to the second portion 1012 , the hardness of the first portion 1011 may gradually decrease, and the hardness of the second portion 1012 may also gradually decrease.

[0099] Exemplarily, the connector 101 may include a first layer and a second layer stacked together, the material hardness of the first layer is greater than the material hardness of the second layer, and the thickness ratio of the first layer to the second layer gradually decreases along the direction from the first part 1011 to the second part 1012, thereby making the yield strength of the second part 1012 smaller than the yield strength of the first part 1011.

[0100] In the above embodiment, the hardness of the material of the second part 1012 is less than the hardness of the material of the first part 1011. Therefore, the hardness of the second part 1012 can be made smaller than the hardness of the first part 1011. When the wire harness 102 is deformed, the second part 1012 will also deform to a certain extent. In this way, fatigue fracture is not likely to occur at the connection position between the wire harness 102 and the connector 101, which is conducive to extending the service life.

[0101] Figure 5 Schematic diagram of the structure of the connecting member 101 in the connecting structure 10 provided in some other embodiments of the present application. Figure 6 A side view of a connecting member 101 in a connecting structure 10 provided in some other embodiments of the present application.

[0102] In some embodiments, reference may be made to Figure 5 and Figure 6 The second part 1012 includes multiple layers of foil 1013 arranged in a stacked manner, and the edges of the multiple layers of foil 1013 are all connected to the first part 1011.

[0103] As a result, the yield strength of the second part 1012 is smaller than that of the first part 1011 , and the second part 1012 is more deformable, which is beneficial to improving the degree of coordinated deformation of the second part 1012 and the wire bundle 102 , thereby improving the stability of the connection between the two.

[0104] In the above technical solution, the multi-layered foil 1013 has good structural flexibility, which is conducive to increasing the contact area between the wire bundle 102 and evenly distributing the current, reducing local current density and reducing the risk of overheating. At the same time, the performance consistency of the connector 101 is good.

[0105] In some embodiments, the first part 1011 is constructed to be formed as a whole by heat-treating the foil 1013. In other words, during the preparation of the connector 101, the multiple layers of foil 1013 can be overlapped along their thickness direction, and part of the foil 1013 can be heat-treated so that the foil 1013 is welded to form the first part 1011, and the unwelded part forms the second part 1012.

[0106] For example, before welding the multi-layer foil 1013 and the wire bundle 102 , the copper foil may be passivated or plated (eg, tinned) to inhibit high-temperature oxidation, ensure welding quality, reduce pores and cold solder joints, and ensure interface conductivity.

[0107] For example, the thickness of the foil 1013 can be 0.1 mm to 0.5 mm. Setting the thickness of the foil 1013 to be greater than or equal to 0.1 mm prevents the thickness of the foil 1013 from being too small, thereby reducing processing difficulty and improving the structural strength of the foil 1013. Setting the thickness of the foil 1013 to be less than or equal to 0.5 mm prevents the thickness of the foil 1013 from being too large, thereby improving the flexibility of the foil 1013.

[0108] In some embodiments, the second portion 1012 is connected to the wire bundle 102 along a side surface in the stacking direction of the foils 1013 .

[0109] Exemplarily, the second portion 1012 is connected to the wire bundle 102 along one side surface in the stacking direction of the foils 1013. Exemplarily, the second portion 1012 is connected to the wire bundle 102 along both side surfaces in the stacking direction of the foils 1013.

[0110] In the above embodiment, when connecting, the wire bundle 102 is directly placed on the side surface of the second part 1012 along the stacking direction of the foil 1013, and then welded or conductively bonded, which is conducive to improving the convenience of the connection operation.

[0111] In some embodiments, reference may be made to Figure 4 The wire bundle 102 includes a plurality of wires 1021 , at least some of the wires 1021 are disposed between the two foils 1013 and connected to the foils 1013 .

[0112] For example, each of the plurality of foils 1013 may be connected to a wire 1021. Alternatively, some of the wires 1021 may be disposed between the plurality of foils 1013, and some of the wires 1021 may be connected to a side surface of the second portion 1012 along the stacking direction of the foils 1013. Alternatively, all of the wires 1021 may be disposed between two foils 1013.

[0113] In the above embodiment, the connection area between the conductive wire 1021 and the foil 1013 is increased, thereby improving the current carrying capacity of the connection structure 10 .

[0114] In some embodiments, the second portion 1012 is connected to the wire bundle 102 along a side surface in the stacking direction of the foils 1013 , and any two adjacent foils 1013 are connected to each other.

[0115] Exemplarily, the second portion 1012 includes multiple layers of foils 1013 , and the second portion 1012 is configured to pre-fix the foils 1013 before connecting the wire harness 102 and the second portion 1012 , so that any two adjacent layers of foils 1013 are connected to each other.

[0116] It should be noted that after the first portion 1011 is connected to the connection end, the multi-layer foil 1013 may be in a scattered state due to transportation or other reasons.

[0117] In the above situation, at least one side edge of the multiple foils 1013 can be interconnected via a weld point, so that any two adjacent layers of foils 1013 are interconnected, thereby allowing the multi-layer foils 1013 to be restored to a stacked state, facilitating subsequent welding or bonding with the wire harness 102. This also increases the flow area of ​​the multi-layer foils 1013 and improves flow performance. Alternatively, the multi-layer foils 1013 can be pre-compressed so that the multi-layer foils 1013 are at least partially attached to each other, allowing the multi-layer foils 1013 to be restored to a stacked state, thereby facilitating subsequent welding or bonding with the wire harness 102. This also increases the flow area of ​​the multi-layer foils 1013 and improves flow performance.

[0118] In some embodiments, the annealing temperature of the first portion 1011 is lower than the annealing temperature of the second portion 1012 .

[0119] It should be noted that, generally, a higher annealing temperature reduces the metal's hardness through recrystallization and grain coarsening. Therefore, the first portion 1011 and the second portion 1012 exhibit different hardnesses, resulting in the first portion 1011 having a greater hardness than the second portion 1012. This can be seen in the different colors of the first portion 1011 and the second portion 1012.

[0120] In the above technical solution, the annealing temperature of the first part 1011 and the second part 1012 is controlled so that the first part 1011 and the second part 1012 have different hardnesses. In this way, the processing cost of the connector 101 is low and the processing flexibility is good. At the same time, other properties of the material itself can be retained without considering the problem of alloying defects.

[0121] In some embodiments, the first part 1011 includes a main body 1014 and a transition part 1015, and the transition part 1015 is connected between the main body 1014 and the second part 1012; the transition part 1015 includes a first section 1016 and a second section 1017, and the main body 1014, the first section 1016, the second section 1017 and the second part 1012 are connected in sequence, the hardness of the first section 1016 is less than the hardness of the main body 1014, the hardness of the first section 1016 is greater than the hardness of the second section 1017, and the hardness of the second section 1017 is greater than the hardness of the second part 1012.

[0122] In the above technical solution, the main body 1014 and the second portion 1012 are connected by a transition portion 1015. The provision of transition portion 1015 can reduce the sudden change in stiffness when the main body 1014 and the second portion 1012 are directly connected, thereby reducing stress concentration, lowering the risk of cracking, and extending service life. The second portion 1012 absorbs energy, while the main body 1014 maintains strength. Combined with transition portion 1015, this allows for a coordinated response under dynamic loads, improving the vibration resistance of connector 101.

[0123] In the above technical solution, the hardness of the main body 1014, the transition part 1015 and the second part 1012 can be gradually transitioned, reducing the risk of stress concentration at the position where the hardness changes significantly due to the significant change in hardness, which is prone to fatigue fracture, and is beneficial to improving the service life of the connector 101.

[0124] In some embodiments, reference may be made to Figures 3 to 6 , along the first direction, the main body 1014 , the transition portion 1015 and the second portion 1012 are arranged in sequence, and the main body 1014 and the second portion 1012 are staggered, and the first direction is perpendicular to the thickness direction of the second portion 1012 .

[0125] Here, the staggered arrangement of the main body 1014 and the second part 1012 along the first direction means that when the connector 101 is observed along the first direction, there is a height difference between the main body 1014 and the second part 1012 relative to the same reference plane.

[0126] In the above technical solution, the main body 1014 and the second part 1012 are staggered. When the connecting member 101 is subjected to stress along the first direction, part of the stress is absorbed by the deformation of the transition part 1015, which can reduce the direct extrusion or impact of the second part 1012 on the main body 1014 and reduce the risk of damage to the main body 1014.

[0127] In some embodiments, the hardness of the transition portion 1015 gradually decreases along the direction from the main portion 1014 to the second portion 1012 .

[0128] For example, the annealing temperature of the transition portion 1015 gradually increases along the direction from the main portion 1014 to the second portion 1012. For example, the transition portion 1015 includes a first metal layer 1018 and a second metal layer 1019 connected to each other. The hardness of the material of the first metal layer 1018 is greater than the hardness of the material of the second metal layer 1019. Along the direction from the main portion 1014 to the second portion 1012, the ratio of the thickness of the first metal layer 1018 to the thickness of the second metal layer 1019 gradually decreases.

[0129] In the above embodiment, the load transfer between the main body 1014 and the second part 1012 can be further made more natural, local overload can be avoided, the load-bearing efficiency of the overall structure can be improved, the degree of hardness mutation at the interface can be reduced, and the risk of cracks can be reduced.

[0130] In some embodiments, the annealing temperature of the first section 1016 is lower than the annealing temperature of the second section 1017 .

[0131] It should be noted that, generally, higher annealing temperatures reduce metal hardness through recrystallization and grain coarsening. The first segment 1016 and the second segment 1017 exhibit different hardnesses, resulting in the first segment 1016 having a greater hardness than the second segment 1017. This can be seen by the different colors of the first segment 1016 and the second segment 1017, which are different in appearance.

[0132] In the above technical solution, the annealing temperature of the first section 1016 and the second section 1017 is controlled to make the hardness of the first section 1016 greater than the hardness of the second section 1017. In this way, the processing cost of the connector 101 is lower and the processing flexibility is better. At the same time, other properties of the material itself can be retained without considering the problem of alloying defects. It can also reduce the hardness mutation effect between the main body 1014 and the second part 1012.

[0133] Figure 7 This is a schematic structural diagram of the transition portion 1015 in the connection structure 10 provided in some embodiments of the present application.

[0134] like Figure 7 As shown, in some embodiments, the transition portion 1015 includes a connected first metal layer 1018 and a second metal layer 1019, the hardness of the material of the first metal layer 1018 is greater than the hardness of the material of the second metal layer 1019, and along the direction from the main body 1014 to the second part 1012, the ratio of the thickness of the first metal layer 1018 to the thickness of the second metal layer 1019 gradually decreases.

[0135] Since the hardness of the first metal layer 1018 is greater, the portion where the ratio of the thickness of the first metal layer 1018 to the thickness of the second metal layer 1019 is greater has a greater hardness; since the hardness of the second metal layer 1019 is smaller, the portion where the ratio of the thickness of the first metal layer 1018 to the thickness of the second metal layer 1019 is smaller has a smaller hardness.

[0136] In the above technical solution, by changing the thickness ratio between the first metal layer 1018 and the second metal layer 1019, the transition part 1015 has a gradually decreasing hardness along the direction from the main body 1014 to the second part 1012. In this way, the range of the hardness gradient of the transition part 1015 can be flexibly controlled.

[0137] In some embodiments, the second portion 1012 is welded to the wire bundle 102 , or in other words, the second portion 1012 is connected to the wire bundle 102 by welding.

[0138] In the above technical solution, second portion 1012 is welded to wire harness 102. This ensures stable contact resistance between second portion 1012 and wire harness 102, making it less susceptible to oxidation, contamination, or loosening, and resulting in a long service life. Furthermore, second portion 1012 has a low hardness and good flexibility, which matches the melting point of wire harness 102 well, resulting in better welding compatibility. The weld creates a metallurgical bond, eliminates the risk of loosening, and significantly outperforms bolted connections in terms of vibration and thermal cycling resistance.

[0139] In some embodiments, the battery device 100 includes a battery cell 20 , the battery cell 20 includes a terminal, and the first portion 1011 is welded to the terminal.

[0140] In the above technical solution, the yield strength of the first part 1011 is greater than the yield strength of the second part 1012, and the hardness of the first part 1011 is usually greater than the hardness of the second part 1012. Welding the first part 1011 to the pole is conducive to improving the welding quality, thereby improving the connection stability between the first part 1011 and the pole.

[0141] In some embodiments, the first portion 1011 can be directly connected to a connection end by welding or bolting, and the connection stability is good.

[0142] Exemplarily, a connection end and the first part 1011 can be connected by laser welding or ultrasonic welding. For example, during laser welding, a pulse mode is used, and the energy density and scanning speed are matched with the melting point of the first part 1011 to control the heat input and reduce the possibility of performance degradation of the second part 1012.

[0143] In some embodiments, the wire harness 102 and the other connection terminal can be connected by welding or bonding, which helps reduce contact resistance and maintain long-term stability, thereby reducing energy loss and the possibility of thermal failure. Compared with bolted connections, the required installation space is smaller, thereby improving space utilization within the battery device 100 and meeting the compact design requirements of high-energy-density battery packs. The weld interface resistance between the wire harness 102 and the other connection terminal is low and long-term stable, which can reduce energy loss and heat generation.

[0144] In some embodiments, the main body 1014 is a copper alloy.

[0145] Exemplarily, the main body 1014 is a cold-pressed copper alloy part, meaning it is cold-pressed from a copper alloy. Exemplarily, the main body 1014 is a heat-treated, reinforced copper alloy part, meaning it is heat-treated and reinforced from a copper alloy. This provides the main body 1014 with greater structural strength, resulting in improved connection stability and strength when welded or bolted to the connection end.

[0146] Furthermore, the main body 1014 is configured to have a surface that is finely processed to ensure the surface flatness of the main body 1014 and to be suitable for high-precision processes such as laser welding.

[0147] In some embodiments, reference may be made to Figures 3 to 6 As shown, the main body 1014 is a flat plate.

[0148] For example, the main body 1014 used to connect with the pole of the battery cell 20 is a flat plate.

[0149] In the above technical solution, the main body 1014 is a flat plate. In this way, the connection area between the main body 1014 and the connection end is large, the connection stability is good, the flow performance is good, the space occupied is small, and the structure is simple.

[0150] In some embodiments, the connection structure 10 includes two connection members 101 , and the two connection members 101 are respectively connected to two ends of the wire bundle 102 .

[0151] The connection structure 10 of this embodiment can be provided with one or two connectors 101 depending on the actual application scenario. For example, when the connection structure 10 is used to connect two battery modules or two battery cells 20, two connectors 101 can be provided; when the connection structure 10 is used to connect a busbar and a charging port, only one connector 101 can be provided.

[0152] In the above technical solution, the connection structure 10 includes two connecting parts 101. In this way, the connection structure 10 can be used to connect two connection ends. The two connecting parts 101 are used to connect to the two connection ends respectively, and the connection stability and strength are better. The wire bundle 102 between the two connecting parts 101 and the second parts 1012 of the two connecting parts 101 can better absorb vibration and adapt to the deformation and displacement caused by thermal cycles, thereby reducing the fatigue failure risk caused by direct connection of hard materials, eliminating the mechanical stress concentration and loosening risk of bolt locking, improving connection reliability, and reducing the possibility of thermal failure.

[0153] The present application provides an electrical device, including the battery device 100 of the above embodiment.

[0154] In the above technical solution, by providing the above battery device 100 , the battery device 100 has good structural stability, which can ensure the performance and safety of the battery device 100 , thereby enabling the electrical device equipped with the battery device 100 to have good performance and safety.

[0155] In some embodiments, the electrical device is a vehicle 1000, see Figure 1 , Figure 1 FIG. 1 is a schematic diagram of a vehicle 1000 according to some embodiments of the present application.

[0156] The vehicle disclosed herein may be a new energy vehicle, such as a pure electric vehicle, a hybrid vehicle, or an extended-range vehicle. A battery device 100 is disposed within the vehicle, and the battery device 100 may be located on the vehicle's underbody. The battery device 100 may be used to power the vehicle, for example, as a driving power source, replacing or partially replacing fuel or natural gas.

[0157] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features therein may be combined with each other.

[0158] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Those skilled in the art will readily appreciate that the present invention is susceptible to various modifications and variations. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the present invention.

Claims

1. A battery device, characterized in that: The invention comprises a connecting piece and a wire bundle, wherein the connecting piece comprises a first part and a second part connected to each other, the yield strength of the second part and the yield strength of the wire bundle are both smaller than the yield strength of the first part, and the wire bundle is connected to the second part.

2. The battery device according to claim 1, wherein: The hardness of the material of the second portion is smaller than the hardness of the material of the first portion.

3. The battery device according to claim 1, wherein: The second part includes a plurality of foils stacked together, and edges of the plurality of foils are connected to the first part.

4. The battery device according to claim 3, wherein: The second portion is connected to the wire bundle along a side surface in a stacking direction of the foil sheets.

5. The battery device according to claim 3, wherein: The wire bundle includes a plurality of wires, at least some of which are arranged between the two foils and connected to the foils.

6. The battery device according to claim 4, wherein: Any two adjacent layers of the foils are connected to each other.

7. The battery device according to any one of claims 1 to 6, characterized in that The first portion includes a main body portion and a transition portion, wherein the transition portion is connected between the main body portion and the second portion; The transition portion includes a first section and a second section, and the main body, the first section, the second section and the second part are connected in sequence. The hardness of the first section is less than the hardness of the main body, the hardness of the first section is greater than the hardness of the second section, and the hardness of the second section is greater than the hardness of the second part.

8. The battery device according to claim 7, wherein: Along a first direction, the main body, the transition portion and the second portion are arranged in sequence, and the main body and the second portion are staggered. The first direction is perpendicular to a thickness direction of the second portion.

9. The battery device according to claim 7, wherein: The hardness of the transition portion gradually decreases along a direction from the main body to the second portion.

10. The battery device according to claim 7, wherein: The transition portion includes a first metal layer and a second metal layer connected to each other. The hardness of the material of the first metal layer is greater than the hardness of the material of the second metal layer. Along the direction from the main body to the second part, the ratio of the thickness of the first metal layer to the thickness of the second metal layer gradually decreases.

11. The battery device according to claim 7, wherein: The main body is a copper alloy part; and / or the main body is a flat plate part.

12. The battery device according to any one of claims 1 to 6, wherein: The second portion is welded to the wire bundle; and / or, The battery device includes a battery cell, the battery cell includes a pole, and the first portion is welded to the pole.

13. An electrical device, characterized in that: The battery device comprises the battery device according to any one of claims 1 to 12, wherein the battery device is used to provide electrical energy to the electrical device.

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