Battery device and electric device

Abstract

The embodiment of the utility model provides a battery device and a power utilization device. The battery device comprises a plurality of battery monomers and a confluence part, each battery monomer comprises a shell, an electrode assembly and an electrode terminal, the electrode assembly is arranged in the shell, the shell comprises a first wall, and the electrode terminal is arranged on the first wall; the electrode terminals of two adjacent single batteries are connected through a confluence component; the electrode terminal comprises a first part and a second part, the first part and the second part are arranged in the thickness direction of the first wall, the first part is farther from the electrode assembly than the second part, the cross section area of the first part is smaller than that of the second part, and the peripheral surface of the first part is connected with the peripheral surface of the second part through a step surface; the confluence component is provided with a through hole, and the confluence component is connected to the peripheral face of the first part in a sleeving mode through the through hole. The volume energy density of the battery device can be improved.

Description

Technical Field

[0001] The present application relates to the field of battery technology, and in particular to a battery device and an electrical device. Background Art

[0002] Energy conservation and emission reduction are key to the sustainable development of the automotive industry. Electric vehicles, due to their energy-saving and environmentally friendly advantages, have become an important component of the industry's sustainable development. For electric vehicles, battery devices are a crucial factor in their development.

[0003] Currently, higher requirements are placed on the volume energy density of battery devices. Utility Model Content

[0004] The present application provides a battery device and an electrical device to improve the volume energy density of the battery device.

[0005] In a first aspect, an embodiment of the present application provides a battery device comprising: a plurality of battery cells and a busbar component, wherein the battery cells comprise a shell, an electrode assembly and an electrode terminal, the electrode assembly is arranged in the shell, the shell comprises a first wall, and the electrode terminal is arranged on the first wall; the electrode terminals of two adjacent battery cells are connected through the busbar component; wherein the electrode terminal comprises a first part and a second part, the first part and the second part are arranged along the thickness direction of the first wall, and the first part is farther away from the electrode assembly than the second part, the cross-sectional area of the first part is smaller than the cross-sectional area of the second part, and the first outer peripheral surface of the first part and the second outer peripheral surface of the second part are connected by a step surface; the busbar component is provided with a through hole, and the busbar component is sleeved on the first outer peripheral surface of the first part through the through hole.

[0006] By designing the electrode terminal as a step structure, the busbar component is provided with a through hole that cooperates with the step structure, and the busbar component is sleeved on the first part through the through hole, the height space occupied by the busbar component (the space in the thickness direction mentioned above) can be reduced, and the volume energy density of the battery device can be improved; the joint between the busbar component and the step structure can be welded by laser wire welding or brazing. Compared with laser penetration welding, the required welding energy and the penetration depth are smaller, so that the electrode terminal can be made thinner, which can further reduce the height space occupied by the busbar component and further improve the volume energy density of the battery device. At the same time, it can also solve the problem of cold welding and improve the connection reliability.

[0007] In some embodiments, the current collecting component includes a first surface and a second surface facing each other along a thickness direction thereof, the through hole penetrates the first surface and the second surface, and the first surface contacts the step surface.

[0008] By making the first surface contact with the step surface, the height space occupied by the busbar component can be further reduced, and the volume energy density of the battery device can be further improved. At the same time, the connection area between the busbar component and the electrode terminal can be increased, the flow capacity can be improved, and the charging and discharging reliability can be improved.

[0009] In some embodiments, along the thickness direction, the first portion has a third surface facing away from the second portion; and the second surface is flush with the third surface.

[0010] By making the second surface of the busbar component flush with the third surface of the first part, the busbar component and the electrode terminal share a height, that is, the size of the side of the first wall protruding away from the electrode assembly in the thickness direction is roughly the same. The busbar component does not occupy height space, which can further improve the volume energy density of the battery device.

[0011] In some embodiments, an angle formed between the first outer peripheral surface and the step surface is an obtuse angle.

[0012] The angle formed by the first outer peripheral surface of the first part and the step surface is an obtuse angle, and the inner peripheral surface of the through hole of the conduit component is set to a shape that is compatible with the first outer peripheral surface of the first part, so that the conduit component and the first part are easier and more fitting to connect, and the joint between the two is smaller, which is convenient for laser wire welding or brazing, and can improve welding quality, reduce the risk of cold welding, and improve connection reliability.

[0013] In some embodiments, the first outer peripheral surface is a conical surface.

[0014] Therefore, the conical surface facilitates the installation of the confluence component and the first part, and is conducive to making the joint smaller and improving the welding quality.

[0015] In some embodiments, the first outer peripheral surface includes a plurality of side surfaces connected end to end along the circumference of the first portion, and the side surfaces are inclined surfaces.

[0016] Therefore, since the first outer peripheral surface includes multiple side surfaces, and the multiple side surfaces are inclined surfaces, the connection area between the collecting component and the first part can be increased, which is conducive to making the joint smaller and improving the welding quality.

[0017] In some embodiments, the busbar component is welded to the first portion to form a weld mark, and the weld mark ring is provided on the outer circumference of the first portion.

[0018] The weld mark ring is arranged on the outer peripheral side of the first part. Compared with laser penetration welding, the electrode terminal can be made thinner due to the smaller welding energy, which can further reduce the height space occupied by the busbar component and further improve the volume energy density of the battery device. At the same time, it can also solve the problem of cold welding and improve the connection reliability.

[0019] In some embodiments, along the thickness direction, the first wall has a fourth surface facing away from the electrode assembly, the first portion has a third surface facing away from the second portion, and the distance between the third surface and the fourth surface is in the range of 0.5 mm to 2.5 mm.

[0020] The distance between the third surface and the fourth surface is within the range of 0.5 mm to 2.5 mm, which allows the electrode terminals and the busbar components to be made thinner, reducing the height space occupied and improving the volume energy density of the battery device; and, by preventing the thickness of the electrode terminals and the busbar components from being too small, the flow capacity can be improved, thereby improving the charge and discharge performance.

[0021] In some embodiments, the battery cell further includes an insulating member disposed around the electrode terminal to insulate and isolate the electrode terminal from the first wall; and a gap is defined between the insulating member and the current collecting component along the thickness direction.

[0022] There is a gap between the insulating part and the busbar component, and the insulating part does not interfere with the busbar component, so that the busbar component can be smoothly assembled on the electrode terminal so that the busbar component contacts the step surface, and a safe distance can be maintained between the busbar component and the first wall, eliminating the risk of short circuit.

[0023] In a second aspect, an embodiment of the present application provides an electrical device, comprising the battery device described in any one embodiment of the first aspect.

[0024] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without creative work.

[0026] Figure 1 A schematic structural diagram of a vehicle provided in some embodiments of the present application;

[0027] Figure 2 An exploded view of the structure of a battery device provided in some embodiments of the present application;

[0028] Figure 3An exploded view of the structure of a battery cell provided in some embodiments of the present application;

[0029] Figure 4 A schematic diagram of the structure of a battery cell array provided in some embodiments of the present application;

[0030] Figure 5 A schematic structural diagram of a battery cell and a busbar component provided in some embodiments of the present application;

[0031] Figure 6 for Figure 5 A partial enlarged schematic diagram of part A in the middle;

[0032] Figure 7 A side view of a battery cell and a busbar component provided for some embodiments of the present application;

[0033] Figure 8 for Figure 7 A partial enlarged schematic diagram of part B in the middle;

[0034] Figure 9 for Figure 7 A partial enlarged schematic diagram of the middle C part;

[0035] Figure 10 Schematic diagram of the structure of battery cells and busbar components provided in other embodiments of the present application;

[0036] Figure 11 for Figure 10 A partial enlarged schematic diagram of the D part in the middle;

[0037] Figure 12 A top view of two adjacent battery cells connected by a busbar component provided in some embodiments of the present application.

[0038] icon:

[0039] 1000-vehicle; 100-battery device; 200-controller; 300-motor; 10-housing; 11-first sub-housing; 12-second sub-housing; 13-cover; 20-battery cell; 21-housing; 211-first wall; 211a-fourth surface; 22-electrode assembly; 221-ear; 23-electrode terminal; 231-first part; 231a-first peripheral surface; 231b-third surface; 232-second part; 232a-second peripheral surface; 232b-step surface; 24-insulating part; 30-collecting part; 30a-first surface; 30b-second surface; 31-through hole; 40-weld mark. DETAILED DESCRIPTION

[0040] The following detailed description of the embodiments of the present application is provided in conjunction with the accompanying drawings and examples. The following detailed description of the embodiments and the accompanying drawings are used to illustrate the principles of the present application, but are not intended to limit the scope of the present application, that is, the present application is not limited to the described embodiments.

[0041] Unless otherwise defined, all technical and scientific terms used in this application have the same meanings as those commonly understood by technicians in the technical field to which this application belongs; the terms used in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" in the specification of this application and the above-mentioned drawings and any variations thereof are intended to cover non-exclusive inclusions.

[0042] The terms "first", "second", etc. in the specification of this application or the above-mentioned drawings are used to distinguish different objects, rather than to describe a specific order or a primary-secondary relationship.

[0043] References to "embodiments" in this application mean that a particular feature, structure, or characteristic described in connection with the embodiment may be included in at least one embodiment of the application. 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. It is understood, both explicitly and implicitly, by those skilled in the art that the embodiments described in this application may be combined with other embodiments.

[0044] In the description of this application, 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 connections between two components. Those skilled in the art will understand the specific meanings of the above terms in this application based on specific circumstances.

[0045] The term "and / or" in this application simply describes an association 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. In addition, the character " / " in this application generally indicates that the related objects are in an "or" relationship.

[0046] The term "multiple" used in this application refers to more than two (including two). Similarly, "multiple groups" refers to more than two (including two) groups, and "multiple sheets" refers to more than two (including two) sheets.

[0047] The following detailed description of the embodiments of the present application is provided in conjunction with the accompanying drawings and examples. The following detailed description of the embodiments and the accompanying drawings are used to illustrate the principles of the present application, but are not intended to limit the scope of the present application, that is, the present application is not limited to the described embodiments.

[0048] Unless otherwise defined, all technical and scientific terms used in this application have the same meanings as those commonly understood by technicians in the technical field to which this application belongs; the terms used in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" in the specification of this application and the above-mentioned drawings and any variations thereof are intended to cover non-exclusive inclusions.

[0049] The terms "first", "second", etc. in the specification of this application and the above-mentioned drawings are used to distinguish different objects, rather than to describe a specific order or a primary-secondary relationship.

[0050] The battery device 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.

[0051] In some embodiments, a battery cell assembly may be formed by arranging multiple battery cells. For example, the battery cell assembly may be a battery module, which is formed by arranging and fixing multiple battery cells to form a single module. For example, a battery module may be formed by bundling multiple battery cells with cable ties.

[0052] 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.

[0053] 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.

[0054] As an example, the battery cell assembly may also be housed in the box by directly fixing a plurality of battery cells to the box.

[0055] As an example, the housing may include a first sub-housing and a second sub-housing. The first and second sub-housings snap together 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 sub-housing may be a top cover or a bottom plate.

[0056] 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.

[0057] As an example, the box body can be used as a part of the chassis structure of the vehicle. For example, the top cover of the box body can become at least a part of the floor of the vehicle, or the frame of the box body can become at least a part of the crossbeam and longitudinal beam of the vehicle.

[0058] In some embodiments, the battery device refers to an energy storage device, which includes a box with a door on at least one side. The energy storage device includes an energy storage container, an energy storage cabinet, etc.

[0059] In the embodiment of the present application, the battery cell may be a secondary battery. A secondary battery refers to a battery cell that can be continuously used by activating active materials by charging after the battery cell is discharged.

[0060] The battery cells may be, but are not limited to, lithium-ion batteries, sodium-ion batteries, sodium-lithium-ion batteries, lithium metal batteries, sodium metal batteries, lithium-sulfur batteries, magnesium-ion batteries, nickel-hydrogen batteries, nickel-cadmium batteries, lead-acid batteries, and the like.

[0061] A battery cell includes an electrode assembly. This assembly consists of a positive electrode, a negative electrode, and a separator. During the charge and discharge process, active ions (such as lithium ions) move back and forth between the positive and negative electrodes. The separator, placed between the positive and negative electrodes, prevents short circuits while allowing the active ions to pass through.

[0062] In some embodiments, a battery cell may include a housing. The housing is used to encapsulate components such as the electrode assembly and electrolyte. The housing may be made of steel, aluminum, plastic (e.g., polypropylene), or a composite metal (e.g., a copper-aluminum composite).

[0063] In some embodiments, the housing includes an end cap assembly and a shell. The shell has an opening. The end cap assembly includes an end cap and an electrode terminal disposed on the end cap. The end cap seals the opening to form a sealed space for accommodating the electrode assembly, electrolyte, and other substances. The shell may have one or more openings. One or more end caps may also be provided.

[0064] In some embodiments, the housing is provided with at least one electrode terminal, which is electrically connected to a tab of the electrode assembly. The electrode terminal may be directly connected to the tab or indirectly connected to the tab via an adapter. The electrode terminal may be provided on an end cap or on the housing.

[0065] In some embodiments, the electrode terminal may include a post and a conductive member, and the post may electrically connect the conductive member and the electrode assembly.

[0066] In some embodiments, the housing is provided with an explosion-proof valve, which is used to release the internal pressure of the battery cell. The explosion-proof valve can be provided on the end cap or on the housing.

[0067] In some embodiments, the housing can be a sealed structure or a non-sealed structure. For example, when the housing is a sealed structure, the housing can protect the electrode assembly and prevent leakage of electrolyte. When the housing is a non-sealed structure, the housing can also protect the electrode assembly. A sealing bag can be included between the housing and the electrode assembly to encapsulate the electrode assembly and electrolyte. Specifically, the sealing bag can be a bag-shaped insulating member or an aluminum-plastic film.

[0068] As an example, the battery cells may be cylindrical, prismatic, soft-pack or other shaped battery cells. Prismatic battery cells include square-shell, blade-shaped, and polygonal batteries. Polygonal batteries may be, for example, hexagonal batteries.

[0069] Currently, in battery devices, busbars are stacked flat on top of the electrode terminals, and the connection between the two is achieved through laser penetration welding. The thickness of the busbars takes up space in height. Furthermore, laser penetration welding requires high power and deep penetration, and the electrode terminals need to meet a certain thickness to prevent welding through the electrode terminals and burning the electrode assembly inside the battery cell, which further occupies space in height and leads to low volumetric energy density of the battery device. In addition, the busbars are stacked flat on the top surface of the electrode terminals. Due to manufacturing errors, there will be a gap between the busbars and this top surface, which is prone to cold welding problems and poor reliability.

[0070] In this regard, the embodiment of the present application designs the electrode terminal as a step structure, and the busbar component is provided with a through hole that cooperates with the step structure. The busbar component is connected to the step structure through the through hole, which can reduce the height space occupied by the busbar component and improve the volume energy density of the battery device; laser wire welding or brazing can be used to weld the joints between the busbar component and the step structure. Compared with laser penetration welding, the required welding energy and the penetration depth are smaller, so that the electrode terminal can be made thinner, which can further reduce the height space occupied by the busbar component and further improve the volume energy density of the battery device. At the same time, it can also solve the problem of cold welding and improve the connection reliability.

[0071] The battery device disclosed in the embodiments of the present application can be used, but is not limited to, in electrical devices such as vehicles, ships, or aircraft. The battery device disclosed in the present application can be used to form a power supply system for the electrical device.

[0072] The technical solutions described in the embodiments of the present application are applicable to various electrical devices that use battery devices, such as mobile phones, portable devices, laptop computers, electric vehicles, electric toys, electric tools, vehicles, ships and spacecraft, etc. For example, spacecraft include airplanes, rockets, space shuttles and spacecraft, etc.

[0073] For the convenience of description, the following embodiments are described by taking a vehicle as an example of an electrical device according to an embodiment of the present application.

[0074] Reference Figure 1 Vehicle 1000 may be a fuel-powered vehicle, a gas-powered vehicle, or a new energy vehicle. The new energy vehicle may be a pure electric vehicle, a hybrid vehicle, or an extended-range vehicle. A battery device 100 is disposed within vehicle 1000. Battery device 100 may be located at the bottom, front, or rear of vehicle 1000. Battery device 100 may be used to power vehicle 1000. For example, battery device 100 may serve as an operating power source for vehicle 1000 and may be used in the circuit system of vehicle 1000, such as for starting, navigation, and operating the vehicle.

[0075] 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.

[0076] In some embodiments of the present application, the battery device 100 can serve not only as an operating power source for the vehicle 1000 , but also as a driving power source for the vehicle 1000 , replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1000 .

[0077] Reference Figure 2 The battery device 100 includes a case 10 and a battery cell 20, and the battery cell 20 is accommodated in the case 10. The case 10 is used to provide a storage space for the battery cell 20, and the case 10 can adopt a variety of structures. In some embodiments, the case 10 may include a first sub-case 11 and a second sub-case 12, and the first sub-case 11 and the second sub-case 12 cover each other, and the first sub-case 11 and the second sub-case 12 jointly define a storage space for accommodating the battery cell 20. The second sub-case 12 can be a hollow structure with one end open, and the first sub-case 11 can be a plate-shaped structure, and the first sub-case covers the open side of the second sub-case 12, so that the first sub-case 11 and the second sub-case 12 jointly define a storage space; the first sub-case 11 and the second sub-case 12 can also be hollow structures with one side open, and the open side of the first sub-case 11 covers the open side of the second sub-case 12.

[0078] In the battery device 100, there can be multiple battery cells 20, and the multiple battery cells 20 can be connected in series, in parallel, or in a mixed connection. Mixed connection means that the multiple battery cells 20 are connected in series and in parallel. The multiple battery cells 20 can be directly connected in series, in parallel, or in a mixed connection, and then the whole formed by the multiple battery cells 20 is accommodated in the box 10; of course, the battery device 100 can also be a battery module formed by first connecting multiple battery cells 20 in series, in parallel, or in a mixed connection, and then the multiple battery modules are connected in series, in parallel, or in a mixed connection to form a whole, and then accommodated in the box 10. The battery device 100 can also include other structures. For example, the battery device 100 can also include a busbar component 30 ( Figure 4 As shown), it is used to realize the electrical connection between multiple battery cells 20.

[0079] The battery device 100 may further include a cover plate 13 covering the battery cell 20 . The cover plate 13 may be made of an insulating material.

[0080] Reference Figure 3 The battery cell 20 includes a housing 21, an electrode assembly 22, and other functional components. The housing 21 may include a shell and an end cap. The shell has an opening, and the end cap closes the opening to isolate the internal environment of the battery cell 20 from the external environment.

[0081] The housing and the end cap cooperate to form an internal environment space for accommodating the battery cell 20, wherein the formed internal environment space can be used to accommodate the electrode assembly 22, electrolyte, and other components. One or more electrode assemblies 22 can be accommodated within the outer shell 21. The outer shell 21 can be of various shapes and sizes. Specifically, the shape of the outer shell 21 can be determined according to the specific shape and size of the electrode assembly. The outer shell 21 can be made of a variety of materials, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc.

[0082] The end cap can be made of a material with a certain hardness and strength (such as aluminum alloy). In this way, the end cap is not easily deformed when squeezed or collided, so that the battery cell 20 can have a higher structural strength and the reliability can also be improved. The material of the end cap can also be various, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., and the embodiments of the present application do not impose any special restrictions on this. In some embodiments, an insulating structure can also be provided on the inner side of the end cap. The insulating structure can be used to isolate the electrical connection components in the housing from the end cap to reduce the risk of short circuit. Exemplarily, the insulating structure can be plastic, rubber, etc.

[0083] Refer to 2 to Figure 12 , the battery device 100 of the embodiment of the present application is described in detail.

[0084] The battery device 100 provided in an embodiment of the present application includes a plurality of battery cells 20 and a busbar assembly 30. The battery cells 20 include a housing 21, an electrode assembly 22, and electrode terminals 23. The electrode assembly 22 is disposed within the housing 21, which includes a first wall 211. The electrode terminals 23 are disposed on the first wall 211. The electrode terminals 23 of two adjacent battery cells 20 are connected by the busbar assembly 30. The electrode terminals 23 include a first portion 231 and a second portion 232. The first portion 231 and the second portion 232 are arranged along the thickness direction Z of the first wall 211. The first portion 231 is further away from the electrode assembly 22 than the second portion 232. The cross-sectional area of the first portion 231 is smaller than that of the second portion 232. The first outer circumferential surface 231a of the first portion 231 and the second outer circumferential surface 232a of the second portion 232 are connected by a stepped surface 232b. The busbar assembly 30 is provided with a through hole 31. The busbar assembly 30 is sleeved onto the outer circumferential surface of the first portion 231 through the through hole 31.

[0085] The plurality of battery cells 20 are electrically connected via the busbar 30 to achieve series and / or parallel connection of the plurality of battery cells 20. The number of the plurality of battery cells 20 may be two, three, or more. The plurality of battery cells 20 may be arranged in one row or multiple rows.

[0086] Figure 2 The diagram shows a situation where multiple battery cells 20 form three rows. The multiple battery cells 20 in each row are arranged along a first direction X. The three rows of battery cells 20 are distributed along a second direction Y. In each row of battery cells 20, the electrode terminals 23 of two adjacent battery cells 20 are connected in series via a busbar 30.

[0087] The housing 21 is used to accommodate the electrode assembly 22. The housing 21 may include a first wall 211, which may be any wall of the housing 21. In some embodiments, the first wall 211 may be an end cap.

[0088] The electrode assembly 22 may be a wound structure or a laminated structure. The battery cell 20 may be a square battery cell 20. For example, the electrode assembly 22 may be flat. The thickness direction of the electrode assembly 22 ( Figure 3 The direction of the arrow X in the middle (the direction in which the arrow X is located) may be perpendicular to the thickness direction Z of the first wall 211.

[0089] The electrode terminal 23 is used to output or input electrical energy. In some embodiments, a tab 221 is provided at one end of the electrode assembly 22, and the electrode terminal 23 is electrically connected to the tab 221. The electrode terminal 23 can be directly connected to the tab 221 or indirectly connected via an adapter. The electrode terminal 23 can be square, cylindrical, or polygonal, with the polygon being, for example, square. The electrode terminal 23 can be made of a conductive material such as aluminum, copper, steel, aluminum alloy, or copper-aluminum alloy.

[0090] The electrode terminal 23 can have a split structure. For example, the electrode terminal 23 includes a post and a riveted block riveted together. The post electrically connects the electrode assembly 22 and the riveted block, and the first portion 231 and the second portion 232 form the riveted block. Alternatively, the electrode terminal 23 can have a one-piece structure, with one end passing through the first wall 211 to electrically connect to the electrode assembly 22, and the other end extending outside the housing 21 to connect to the current collector 30. The first portion 231 and the second portion 232 extend outside the housing 21.

[0091] The first portion 231 and the second portion 232 form a stepped structure. Specifically, the first portion 231 and the second portion 232 are arranged along the thickness direction Z of the first wall 211, with the first portion 231 being further away from the electrode assembly 22 than the second portion 232. The thickness direction Z of the first wall 211 may be the height direction of the battery cell 20. The first portion 231 is located on the side of the second portion 232 that is further away from the electrode assembly 22.

[0092] The cross-sectional area of the first portion 231 is smaller than the cross-sectional area of the second portion 232. That is, within the same projection plane perpendicular to the thickness direction Z, the orthographic projection of the first portion 231 lies within the orthographic projection of the second portion 232. The cross-sectional area of the first portion 231 can be calculated by taking the cross section perpendicular to the thickness direction Z to obtain the area of the cross section of the first portion 231. The cross-sectional area of the second portion 232 can be calculated by taking the cross section perpendicular to the thickness direction Z to obtain the area of the cross section of the second portion 232.

[0093] The first outer circumferential surface 231 a of the first portion 231 and the second outer circumferential surface 232 a of the second portion 232 are connected by a stepped surface 232 b .

[0094] Reference Figure 5 and Figure 6 Along the thickness direction Z, the first portion 231 has a third surface 231b facing away from the second portion 232. The stepped surface 232b is closer to the electrode assembly 22 than the third surface 231b. For example, in an upright battery cell 20, the stepped surface 232b is lower than (sunken below) the third surface 231b. The first portion 231 and the second portion 232 can be formed by cutting away a portion of the electrode terminal 23.

[0095] The conduit component 30 is provided with a through hole 31, and the shape and / or size of the inner circumference of the through hole 31 can match the shape and / or size of the first outer circumference 231a of the first part 231, so that when the conduit component 30 is sleeved on the first outer circumference 231a of the first part 231 through the through hole 31, the inner circumference of the through hole 31 and the first outer circumference 231a of the first part 231 are in contact with each other.

[0096] The busbar component 30 is sleeved on the first outer peripheral surface 231a of the first portion 231 through the through hole 31, so that at least a portion of the busbar component 30 can be lower than the first portion 231. Compared with the method of stacking the busbar component 30 on the top surface of the electrode terminal 23, the space occupied by the busbar component 30 in the thickness direction Z can be reduced. The busbar component 30 can be in contact with the stepped surface 232b or not, which can also reduce the space occupied by the busbar component 30 in the thickness direction Z.

[0097] The busbar component 30 may be provided with two through holes 31 , and the busbar component 30 is respectively sleeved on the first portions 231 of the electrode terminals 23 of the two battery cells 20 through the two through holes 31 to achieve electrical connection between the two battery cells 20 .

[0098] The connection between the busbar component 30 and the first part 231 can be achieved by laser wire welding or brazing. Compared with the method of stacking the busbar component 30 on the top surface of the electrode terminal 23 and using laser penetration welding, the welding energy required is lower and the penetration depth is shallower.

[0099] By designing the electrode terminal 23 as a step structure, the busbar component 30 is provided with a through hole 31 that cooperates with the step structure. The busbar component 30 is sleeved on the first part 231 through the through hole 31, which can reduce the height space occupied by the busbar component 30 (the space in the thickness direction Z mentioned above) and improve the volume energy density of the battery device 100; laser wire welding or brazing can be used to weld the joint between the busbar component 30 and the step structure. Compared with laser penetration welding, the required welding energy and the penetration depth are smaller, so that the electrode terminal 23 can be made thinner, which can further reduce the height space occupied by the busbar component 30 and further improve the volume energy density of the battery device 100. At the same time, it can also solve the problem of cold welding and improve the connection reliability.

[0100] In some embodiments, reference Figures 6 to 9 The conduit component 30 includes a first surface 30 a and a second surface 30 b opposite to each other along the thickness direction Z thereof. The through hole 31 penetrates the first surface 30 a and the second surface 30 b . The first surface 30 a contacts the step surface 232 b .

[0101] The first surface 30a is closer to the first wall 211 than the second surface 30b. The first surface 30a and the stepped surface 232b may be in direct contact with each other without welding.

[0102] The first surface 30a contacts the step surface 232b, which can further reduce the height space occupied by the busbar component 30, further improve the volume energy density of the battery device 100, and at the same time increase the connection area between the busbar component 30 and the electrode terminal 23, thereby improving the flow capacity and the charging and discharging reliability.

[0103] In some embodiments, along the thickness direction Z, the first portion 231 has a third surface 231 b facing away from the second portion 232 ; the second surface 30 b is flush with the third surface 231 b .

[0104] “The second surface 30b is flush with the third surface 231b” can be understood as the second surface 30b and the third surface 231b are substantially in the same horizontal plane with almost no height difference between the two. However, the height difference is not absolutely zero and can be allowed within the range of manufacturing error or assembly error.

[0105] The second surface 30b of the busbar component 30 is flush with the third surface 231b of the first part 231, so that the busbar component 30 and the electrode terminal 23 share a height, that is, the size of the side protruding from the first wall 211 away from the electrode assembly 22 along the thickness direction Z is roughly the same. The busbar component 30 does not occupy height space and can further improve the volume energy density of the battery device 100.

[0106] In some embodiments, the angle a formed between the first outer peripheral surface 231a of the first portion 231 and the stepped surface 232b is an obtuse angle. Angle a can be, for example, 95°, 100°, 120°, 130°, 140°, 150°, 160°, or 170°. This arrangement allows the first outer peripheral surface 231a of the first portion 231 to be inclined relative to the thickness direction Z. The inner peripheral surface of the through hole 31 of the conduit component 30 is configured to match the first outer peripheral surface 231a of the first portion 231.

[0107] The angle a formed by the first outer peripheral surface 231a of the first part 231 and the step surface 232b is an obtuse angle, and the inner peripheral surface of the through hole 31 of the conduit component 30 is set to a shape that is adapted to the first outer peripheral surface 231a of the first part 231, so that the conduit component 30 and the first part 231 are easier and more fitting to be connected, and the joint between the two is smaller, which is convenient for laser wire welding or brazing, and can improve the welding quality, reduce the risk of cold welding, and improve the connection reliability.

[0108] In some embodiments, the outer circumference of the first portion 231 is a conical surface, and the inner circumference of the through hole 31 of the confluence component 30 is in a shape that matches the conical surface.

[0109] Therefore, the conical surface facilitates the installation of the confluence component 30 and the first portion 231 , and is conducive to making the joint smaller and improving the welding quality.

[0110] In some embodiments, the first outer peripheral surface 231a of the first portion 231 includes a plurality of side surfaces connected end to end along the circumference of the first portion 231 (see Figure 11 The inner peripheral surface of the through hole 31 of the confluence component 30 includes a plurality of mating surfaces that mate with the plurality of side surfaces.

[0111] As an example, the first portion 231 is a square body, and the first outer peripheral surface 231 a of the first portion 231 includes four side surfaces.

[0112] Therefore, the first outer peripheral surface 231a of the first part 231 includes multiple side surfaces, and the multiple side surfaces are inclined surfaces, which can increase the connection area between the conduit component 30 and the first part 231, and is conducive to making the joint smaller and improving the welding quality.

[0113] In some embodiments, reference Figure 12 The conduit component 30 and the first portion 231 are welded to form a weld mark 40 , and the weld mark 40 is arranged around the outer circumference of the first portion 231 .

[0114] Laser wire welding or brazing can be used to connect the confluence component 30 and the first part 231 at the annular joint between the two, so that a weld mark 40 is formed at the annular joint on the outer circumference of the first part 231.

[0115] The weld mark 40 is arranged on the outer peripheral side of the first portion 231. Compared with laser penetration welding, the electrode terminal 23 can be made thinner due to the smaller welding energy, which can further reduce the height space occupied by the busbar component 30 and further improve the volume energy density of the battery device 100. At the same time, it can also solve the problem of cold welding and improve the connection reliability.

[0116] In some embodiments, reference Figure 9 Along the thickness direction Z, the first wall 211 has a fourth surface 211a facing away from the electrode assembly 22, and the first portion 231 has a third surface 231b facing away from the second portion 232. The distance h between the third surface 231b and the fourth surface 211a is in the range of 0.5 mm to 2.5 mm. For example, the distance h between the third surface 231b and the fourth surface 211a can be 0.5 mm, 0.8 mm, 1.5 mm, 1.9 mm, 2 mm, 2.3 mm, 2.4 mm, or 2.5 mm.

[0117] The distance h between the third surface 231b and the fourth surface 211a is in the range of 0.5mm~2.5mm, which can make the electrode terminal 23 and the busbar component 30 thinner, reduce the height space occupied, and improve the volume energy density of the battery device 100; and, the thickness of the electrode terminal 23 and the busbar component 30 is not too small, which can improve the current flow capacity and improve the charging and discharging performance.

[0118] In some embodiments, reference Figure 9The battery cell 20 further includes an insulating member 24 , which is disposed around the electrode terminal 23 to insulate and isolate the electrode terminal 23 from the first wall 211 ; along the thickness direction Z, a gap e is defined between the insulating member 24 and the busbar component 30 .

[0119] The insulating member 24 may include a bottom wall and a peripheral wall. The bottom wall is located between the second portion 232 and the first wall 211 . The peripheral wall surrounds the electrode terminal 23 . A gap e is formed between the side of the peripheral wall facing away from the first wall 211 and the current collecting component 30 .

[0120] The insulating member 24 may only include a peripheral wall, which surrounds the electrode terminal 23 and is located between the electrode terminal 23 and the first wall 211 . A gap e is formed between the side of the peripheral wall facing away from the first wall 211 and the current collecting component 30 .

[0121] There is a gap e between the insulating part 24 and the busbar part 30, and the insulating part 24 does not interfere with the busbar part 30, so that the busbar part 30 can be smoothly assembled on the electrode terminal 23 so that the busbar part 30 contacts the step surface 232b, and a safe distance can be maintained between the busbar part 30 and the first wall 211, eliminating the risk of short circuit.

[0122] In a second aspect, an embodiment of the present application provides an electrical device, comprising the above-mentioned battery device 100 .

[0123] Below, refer to Figures 2 to 12 , a specific example of this application is described.

[0124] In the related art, multiple battery cells are connected by a busbar component, which is installed on the upper surface of the electrode terminal, and the electrical connection between the two is achieved by laser penetration welding. The laser penetration welding has a large power, so the penetration depth is large, which means that the electrode terminal needs to meet a certain thickness to eliminate the risk of liquid leakage due to laser welding; at the same time, since the busbar component is flat on the upper surface of the electrode terminal, the thickness of the busbar component occupies the space dimension; thus, the thickness of the electrode terminal and the thickness of the busbar component both occupy the space dimension, resulting in low space utilization and low volume energy density. In addition, the way the busbar component and the electrode terminal are installed up and down has high requirements on the installation gap, which is prone to the problem of cold welding, resulting in poor reliability.

[0125] To this end, the embodiment of the present application designs the electrode terminal 23 as a step structure, and provides the busbar component 30 with a through hole 31 that matches the step structure, so that the busbar component 30 and the electrode terminal 23 share the same height, effectively reducing the height space occupied. Laser wire welding or brazing is used to weld the butt joint between the busbar component 30 and the electrode terminal 23. Compared with laser penetration welding, shallow penetration welding can be achieved, and the electrode terminal 23 can be made thinner, further reducing the height space occupied and improving the volume energy density of the battery device 100. The busbar component 30 and the electrode terminal 23 are designed to match with a wedge interface, which is easier to assemble, improves the welding effect, and improves the connection reliability.

[0126] In conventional designs, the electrode terminals 23 are typically around 3mm thick, while the busbar 30 is approximately 2mm thick, occupying a total space of over 5mm. In this design, the electrode terminals can be reduced to 1mm or less, sharing the same height as the busbar 30. The overall height can be controlled to under 2.5mm (e.g., 0.5mm-2.5mm), thereby increasing energy density by over 2%. The stepped structure can be either conical or square.

[0127] Although the present application has been described with reference to preferred embodiments, various modifications may be made thereto and components may be substituted with equivalents without departing from the scope of the present application. In particular, the various technical features described in the various embodiments may be combined in any manner as long as there are no structural conflicts. The present application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the present application.

Claims

1. A battery device, characterized in that: include: A plurality of battery cells, each comprising a housing, an electrode assembly, and an electrode terminal, wherein the electrode assembly is disposed within the housing, the housing comprises a first wall, and the electrode terminal is disposed on the first wall; a busbar component, through which the electrode terminals of two adjacent battery cells are connected; The electrode terminal includes a first portion and a second portion, the first portion and the second portion are arranged along the thickness direction of the first wall, the first portion is farther away from the electrode assembly than the second portion, the cross-sectional area of the first portion is smaller than the cross-sectional area of the second portion, and a first outer peripheral surface of the first portion and a second outer peripheral surface of the second portion are connected by a stepped surface; The confluence component is provided with a through hole, and the confluence component is sleeved on the first outer peripheral surface of the first part through the through hole.

2. The battery device according to claim 1, wherein: The current collecting member includes a first surface and a second surface facing each other in a thickness direction thereof. The through hole penetrates the first surface and the second surface. The first surface contacts the stepped surface.

3. The battery device according to claim 2, characterized in that Along the thickness direction, the first portion has a third surface facing away from the second portion; The second surface is flush with the third surface.

4. The battery device according to claim 1, wherein: An angle formed between the first outer peripheral surface and the step surface is an obtuse angle.

5. The battery device according to claim 4, characterized in that The first outer peripheral surface is a conical surface.

6. The battery device according to claim 4, characterized in that The first outer peripheral surface includes a plurality of side surfaces connected end to end along the circumference of the first portion, and the side surfaces are inclined surfaces.

7. The battery device according to any one of claims 1 to 6, characterized in that: The confluence component and the first portion are welded to form a weld mark, and the weld mark ring is provided on the outer circumference of the first portion.

8. The battery device according to any one of claims 1 to 6, characterized in that: Along the thickness direction, the first wall has a fourth surface facing away from the electrode assembly, the first portion has a third surface facing away from the second portion, and a distance between the third surface and the fourth surface is in the range of 0.5 mm to 2.5 mm.

9. The battery device according to any one of claims 1 to 6, characterized in that: The battery cell further includes an insulating member, which is disposed around the electrode terminal to insulate and isolate the electrode terminal from the first wall; A gap is formed between the insulating member and the current collecting component along the thickness direction.

10. An electrical device, characterized in that: include: A battery device according to any one of claims 1 to 9.

Images