Battery device and electric appliance

Abstract

This application provides a battery device and an electrical appliance. The battery device includes: a plurality of battery cell assemblies connected in series, wherein a first battery cell assembly comprises a plurality of battery cells connected in parallel; and a first busbar for connecting the first battery cell and a second battery cell in parallel, the first busbar including a first connection portion, a second connection portion, and a safety portion, wherein the first connection portion is used to connect to the first battery cell, the second connection portion is used to connect to the second battery cell, and the safety portion is located between the first connection portion and the second connection portion, and the safety portion includes a current limiting element. The battery device and electrical appliance of this application can improve the reliability of the battery device.

Description

[0001] This application claims priority to PCT patent application PCT / CN2024 / 129130 entitled "Battery Device and Electrical Equipment", filed on October 31, 2024, the entire contents of which are incorporated herein by reference. Technical Field

[0002] This application relates to the field of battery technology, and in particular to a battery device and an electrical appliance. Background Technology

[0003] Energy conservation and emission reduction are key to the sustainable development of the automotive industry. In this context, electric vehicles, due to their energy-saving and environmentally friendly advantages, have become an important component of the automotive industry's sustainable development. And for electric vehicles, battery technology is a crucial factor in their development.

[0004] To increase the capacity of a battery device, multiple battery cells can be electrically connected in a parallel configuration. However, if any one of these cells experiences thermal runaway, the short-circuit current will generate a large amount of heat, leading to heat dissipation between the parallel-connected cells and posing a safety hazard. Utility Model Content

[0005] This application provides a battery device and an electrical appliance that can improve the reliability of the battery device.

[0006] In a first aspect, a battery device is provided, comprising: a plurality of battery cell assemblies connected in series, wherein a first battery cell assembly comprises a plurality of battery cells connected in parallel; and a first busbar for connecting the first battery cell and a second battery cell in parallel, the first busbar comprising a first connection portion, a second connection portion, and a safety portion, wherein the first connection portion is for connecting to the first battery cell, the second connection portion is for connecting to the second battery cell, and the safety portion is located between the first connection portion and the second connection portion, and the safety portion comprises a current limiting element.

[0007] Therefore, in the case of thermal runaway of the first battery cell, even if the first battery cell itself is close to a short circuit, equivalent to a resistor with a very small resistance, the current in the circuit between the first battery cell and the second battery cell connected in parallel will not be too large due to the safety part including a current limiting element provided between them. This reduces the risk of short circuit, thereby reducing the risk of thermal diffusion and improving the reliability of the battery device.

[0008] In some embodiments, the battery device includes a third busbar and a fourth busbar. The third busbar connects the positive electrode of the first battery cell and the positive electrode of the second battery cell, and the fourth busbar connects the negative electrode of the first battery cell and the negative electrode of the second battery cell. At least one of the third and fourth busbars is a first busbar with a safety feature. When either the third or fourth busbar is a first busbar with a safety feature, the number of busbars with safety features within the battery device can be reduced, lowering the complexity of the internal structure of the battery device, facilitating its processing and assembly, and improving its processing efficiency. When both the third and fourth busbars are first busbars with safety features, the reliability of the battery device can be improved.

[0009] In some embodiments, the number of battery cells connected in parallel in the first battery cell assembly is less than or equal to 10. Including two or more battery cells in parallel in the first battery cell assembly can increase the capacity of the battery device; however, the parallel circuit is limited by factors such as the battery management system, charge / discharge control strategy, and safety considerations, and the number of parallel battery cells in each battery cell assembly should not be excessive.

[0010] In some embodiments, the sum of the resistance values ​​R0 of the current-limiting elements included in the third bus and the fourth bus satisfies: 0.46Ω≤R0≤24.36Ω.

[0011] The sum of the resistance values, R0, should not be too small. For example, it is usually set to R0 ≥ 0.46Ω. In the event of thermal runaway of the first battery cell, this reduces the short-circuit current in the circuit between the first and second battery cells, lowers the risk of thermal propagation in the battery device, and improves the reliability of the battery device. Conversely, the sum of the resistance values, R0, should not be too large either. For example, it is usually set to R0 ≤ 24.36Ω. When a voltage difference is caused by self-discharge in any battery cell in the parallel circuit between the first and second battery cells, the battery device can balance the voltage difference through self-balancing in a short time, meeting the design requirements.

[0012] In some embodiments, the sum of resistances R0 satisfies: 0.92Ω ≤ Rp ≤ 2.71Ω. Appropriately increasing the sum of resistances R0 can further reduce the short-circuit current in the circuit between the first and second battery cells in the event of thermal runaway in the first battery cell, thus reducing the risk of thermal diffusion in the battery device and improving its reliability. Furthermore, limiting the sum of resistances R0 to a minimum can shorten the time required for the battery device to self-balance the voltage difference caused by self-discharge in any battery cell in the parallel circuit between the first and second battery cells, thereby improving the battery device's performance.

[0013] In some embodiments, the first battery cell includes: a housing including a first wall; an electrode terminal disposed on the first wall and electrically insulated from the first wall; and an electrode assembly housed within the housing, the electrode terminal being electrically connected to a first tab of the electrode assembly. The structure is simple and easy to implement.

[0014] In some embodiments, the first connection portion is connected to the electrode terminal to electrically connect the first battery cell to the second battery cell.

[0015] In some embodiments, the second tab of the electrode assembly is electrically connected to the first wall, and the second tab has the opposite polarity to the first tab. The first connection portion is connected to the first wall. The first wall can serve as an electrode terminal and be used for electrical connection with other battery cells, which simplifies the structure of the battery cell and reduces the number of electrode terminals.

[0016] In some embodiments, the safety unit further includes a first connection structure and a second connection structure, the first connection structure being used to connect the first connection part and the current limiting element, and the second connection structure being used to connect the second connection part and the current limiting element, so as to connect the first battery cell and the second battery cell in parallel.

[0017] In some embodiments, the safety element includes a plurality of the first connection structures spaced apart to improve the connection strength between the first connection and the current-limiting element. And / or, the safety element includes a plurality of the second connection structures spaced apart to improve the connection strength between the second connection and the current-limiting element, thereby improving the stability of the safety element.

[0018] In some embodiments, the first busbar component further includes a protective component for protecting the connection between the first connecting portion and the safety portion, and / or protecting the connection between the second connecting portion and the safety portion. This protective component can improve the structural strength of the connection between the first connecting portion and the safety portion, and / or improve the structural strength of the connection between the second connecting portion and the safety portion, thereby reducing the risk of breakage between the safety portion and the first connecting portion and / or between the safety portion and the second connecting portion during the use or transportation of the battery device, such as in the event of a collision, thereby improving the reliability of the battery device.

[0019] In some embodiments, the protective member at least covers: the region of the first connector near the safety part and the region of the safety part near the first connector, to improve the structural strength of the connection between the first connector and the safety part. And / or, the region of the second connector near the safety part and the region of the safety part near the second connector, to improve the structural strength of the connection between the second connector and the safety part.

[0020] In some embodiments, the protective component covers the safety part, the area of ​​the first connecting part near the safety part, and the area of ​​the second connecting part near the safety part to protect the safety part.

[0021] In some embodiments, the protective component is fixed to at least one of the first connecting part, the second connecting part, and the safety part by hot melting and / or casting processes, which is simple to process and easy to implement.

[0022] In some embodiments, the protective component is made of at least one of the following materials: polypropylene, polyimide, and fusible polytetrafluoroethylene, to facilitate processing and improve structural reliability to meet design requirements.

[0023] In some embodiments, the current-limiting element includes at least one of the following: a capacitor, a bonding resistor, a resistance wire, and a diaphragm resistor, which are easy to implement.

[0024] In some embodiments, the safety part is fixed to the first connecting part by welding; and / or, the safety part is fixed to the second connecting part by welding to facilitate processing.

[0025] In some embodiments, the battery device further includes a second busbar for connecting the first battery cell and a third battery cell in series, the third battery cell and the first battery cell belonging to different battery cell assemblies. The second busbar can be used to achieve series connection between different battery cell assemblies.

[0026] In a second aspect, an electrical device is provided, comprising: a battery device as described in the first aspect and any implementation thereof, the battery device being used to supply power to the electrical device.

[0027] In some embodiments, the electrical equipment is a vehicle, a ship, or a spacecraft. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of the structure of a vehicle disclosed in one embodiment of this application;

[0029] Figure 2 This is an exploded structural diagram of a battery device disclosed in an embodiment of this application;

[0030] Figure 3 This is a top view schematic diagram of multiple battery cells electrically connected within a battery device disclosed in an embodiment of this application;

[0031] Figure 4 This is a schematic diagram of the structure of a first busbar component disclosed in an embodiment of this application;

[0032] Figure 5This is a schematic diagram of the connection relationship between individual battery cells in a battery device disclosed in an embodiment of this application;

[0033] Figure 6 This is a schematic diagram of a first battery cell assembly disclosed in an embodiment of this application;

[0034] Figure 7 This is a schematic diagram of the structure of another first busbar component disclosed in an embodiment of this application;

[0035] Figure 8 This is a schematic diagram of the structure of another first busbar component disclosed in an embodiment of this application;

[0036] Figure 9 This is a top view schematic diagram of another first busbar component disclosed in an embodiment of this application;

[0037] Figure 10 This is a schematic diagram of the structure of another first busbar component disclosed in an embodiment of this application;

[0038] Figure 11 This is a top view schematic diagram of another first busbar component disclosed in an embodiment of this application;

[0039] Figure 12 This is a schematic diagram of the structure of a battery cell disclosed in an embodiment of this application;

[0040] Figure 13 This is an exploded view of a partial structure of a battery cell disclosed in an embodiment of this application;

[0041] Figure 14 This is a partial cross-sectional schematic diagram of a battery cell disclosed in an embodiment of this application.

[0042] The accompanying drawings are not drawn to scale. Detailed Implementation

[0043] The technical solutions in the embodiments of this application will now be described with reference to the accompanying drawings.

[0044] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0045] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used in the description of this application is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms "comprising" and "having," and any variations thereof, in the description, claims, and accompanying drawings of this application are intended to cover non-exclusive inclusion. The terms "first," "second," etc., in the description, claims, or accompanying drawings of this application are used to distinguish different objects, not to describe a specific order or hierarchy.

[0046] In this application, the reference to "embodiment" means that a specific feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a mutually exclusive, independent, or alternative embodiment. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described in this application can be combined with other embodiments.

[0047] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "attachment" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0048] In this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Additionally, in this application, the character " / " generally indicates that the preceding and following related objects have an "or" relationship.

[0049] In the embodiments of this application, the same reference numerals denote the same components, and for the sake of brevity, detailed descriptions of the same components are omitted in different embodiments. It should be understood that the thickness, length, width, and other dimensions of various components in the embodiments of this application shown in the accompanying drawings, as well as the overall thickness, length, width, and other dimensions of the integrated device, are merely illustrative and should not constitute any limitation on this application.

[0050] In this application, "multiple" refers to two or more (including two), and similarly, "multiple groups" refers to two or more (including two), and "multiple pieces" refers to two or more (including two).

[0051] In this embodiment of the application, the battery cell can be a secondary battery, which refers to a battery cell that can be recharged to activate the active materials and continue to be used after the battery cell has been discharged.

[0052] The battery cell can be a lithium-ion battery, sodium-ion battery, sodium-lithium-ion battery, lithium metal battery, sodium metal battery, lithium-sulfur battery, magnesium-ion battery, nickel-metal hydride battery, nickel-cadmium battery, lead-acid battery, etc., and the embodiments of this application are not limited to this.

[0053] A single battery cell typically includes an electrode assembly. The electrode assembly includes a positive electrode, a negative electrode, and a separator, with the separator positioned between the positive and negative electrodes. During the charging and discharging process of a single battery cell, active ions (such as lithium ions) repeatedly insert and extract between the positive and negative electrodes. The separator, positioned between the positive and negative electrodes, prevents short circuits while allowing active ions to pass through.

[0054] In some embodiments, the battery cell may include a casing. The casing may be a steel casing, an aluminum casing, a plastic casing (such as a polypropylene casing), a composite metal casing (such as a copper-aluminum composite casing), or an aluminum-plastic film, etc. In some embodiments, the casing may be a sealed structure or a non-sealed structure. As an example, when the casing is a non-sealed structure, the casing serves to protect the electrode assembly, and a sealing bag is included between the casing and the electrode assembly to encapsulate the electrode assembly and electrolyte. Specifically, the sealing bag may be a bag-shaped insulating component or an aluminum-plastic film. When the casing is a sealed structure, it is used to encapsulate components such as the electrode assembly and electrolyte.

[0055] As an example, the battery cell can be a cylindrical battery cell, a prismatic battery cell, a pouch battery cell, or a battery cell of other shapes. Prismatic battery cells include prismatic battery cells, blade-shaped battery cells, and multi-prismatic batteries, such as hexagonal prismatic batteries. This application does not have any particular limitations.

[0056] In some embodiments, the housing includes an end cap and a housing, the housing having an opening, and the end cap covering the opening. The housing may have one or more openings. The end cap may also have one or more.

[0057] In some embodiments, at least one electrode terminal is provided on the housing, and the electrode terminal is electrically connected to the tab. The electrode terminal can be directly connected to the tab, or it can be indirectly connected to the tab through a current collector. The electrode terminal can be provided on the end cap or on the housing.

[0058] The battery apparatus mentioned in the embodiments of this application may include one or more battery cell assemblies for providing voltage and capacity. A battery cell assembly may include multiple battery cells, which are connected in series, parallel, or mixed connections via a busbar.

[0059] In some embodiments, a battery cell assembly is typically formed by arranging multiple battery cells.

[0060] As an example, a battery cell assembly can be a battery module, which is formed by arranging and fixing multiple battery cells together to form an independent module. As another example, a battery module can be formed by bundling multiple battery cells together with cable ties.

[0061] In some embodiments, the battery device may be a battery pack, which includes a housing and one or more individual battery cells housed within the housing.

[0062] As an example, the battery cell assembly can be a battery module, which can be housed in a housing by fixing the battery module in the housing.

[0063] As an example, battery cell assemblies can also be housed in a housing by directly fixing multiple battery cells to the housing.

[0064] As an example, the enclosure may include a first enclosure and a second enclosure. The first enclosure and the second enclosure are fastened together to form a closed space inside the enclosure to house the individual battery cells. Here, "closed" refers to covering or closing, and can be either sealed or unsealed. The first enclosure may be a top cover or a bottom plate.

[0065] As an example, the enclosure may include a top cover, a frame, and a bottom plate. The top cover and bottom plate are connected to the frame, creating an enclosed space inside the enclosure to house the individual battery cells.

[0066] In some embodiments, the housing may be part of the vehicle's chassis structure. For example, a portion of the housing may be at least a part of the vehicle's floor, or a portion of the housing may be at least a part of the vehicle's crossbeams and longitudinal beams.

[0067] The technical solutions described in the embodiments of this application are applicable to various electrical devices that use individual battery cells, such as mobile phones, portable devices, laptops, electric vehicles, electric toys, power tools, vehicles, ships, and spacecraft. For example, spacecraft include airplanes, rockets, space shuttles, and spacecraft.

[0068] The development of battery technology must consider multiple design factors simultaneously, such as energy density, cycle life, discharge capacity, and charge / discharge rate. To increase the capacity of a battery device, multiple battery cells can be electrically connected in parallel. However, in the event of thermal runaway in one of these cells, the runaway cell approximates a short circuit, effectively acting as a very small resistor. This results in a significant current flowing between the runaway cell and the cells connected in parallel. This large current generates substantial heat, leading to thermal diffusion among the parallel cells and posing a safety hazard.

[0069] Therefore, embodiments of this application provide a battery device and an electrical appliance that can solve the above-mentioned problems. The battery device of this application includes a plurality of battery cell assemblies connected in series, wherein the first battery cell assembly includes a plurality of battery cells connected in parallel, the plurality of battery cells including a first battery cell and a second battery cell. The battery device also includes a first busbar for connecting the first battery cell and the second battery cell in parallel. The first busbar includes a first connection portion, a second connection portion, and a safety portion. The first connection portion is used to connect to the first battery cell, the second connection portion is used to connect to the second battery cell, and the safety portion is located between the first connection portion and the second connection portion, and the safety portion includes a current-limiting element. In the event of thermal runaway of the first battery cell, even if the first battery cell itself is approximately short-circuited, equivalent to a resistor with a very small resistance, the current in the circuit between the first and second battery cells will not be excessive due to the safety portion including the current-limiting element between the parallel-connected first and second battery cells, reducing the risk of short circuit, thereby reducing the risk of thermal diffusion and improving the reliability of the battery device.

[0070] The technical solutions described in the embodiments of this application are applicable to various electrical devices that use battery devices.

[0071] Electrical equipment can include vehicles, mobile phones, portable devices, laptops, ships, spacecraft, electric toys, and power tools, etc. Vehicles can be gasoline-powered cars, natural gas-powered cars, or new energy vehicles; new energy vehicles can be pure electric vehicles, hybrid electric vehicles, or range-extended electric vehicles, etc. Spacecraft include airplanes, rockets, space shuttles, and spacecraft, etc. Electric toys include stationary or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys, etc. Power tools include metal cutting power tools, grinding power tools, assembly power tools, and railway power tools, such as electric drills, electric grinders, electric wrenches, electric screwdrivers, electric hammers, impact drills, concrete vibrators, and electric planers, etc. This application does not impose any special limitations on the above-mentioned electrical equipment.

[0072] For ease of explanation, the following embodiments use a vehicle as an example of electrical equipment.

[0073] For example, such as Figure 1 The diagram shown is a structural schematic of a vehicle 1 according to one embodiment of this application. Vehicle 1 can be a gasoline-powered vehicle, a natural gas-powered vehicle, or a new energy vehicle. New energy vehicles can be pure electric vehicles, hybrid electric vehicles, or range-extended electric vehicles, etc. A motor 40, a controller 30, and a battery device 10 can be installed inside vehicle 1. The controller 30 controls the battery device 10 to supply power to the motor 40. For example, the battery device 10 can be installed at the bottom, front, or rear of vehicle 1. The battery device 10 can be used to power vehicle 1. For example, the battery device 10 can serve as the operating power source for vehicle 1, for example, to meet the electrical system requirements of vehicle 1, such as for starting, navigation, and operation. In another embodiment of this application, the battery device 10 can not only serve as the operating power source for vehicle 1, but also as the driving power source for vehicle 1, replacing or partially replacing gasoline or natural gas to provide driving power for vehicle 1.

[0074] Figure 2 An exploded view of a portion of the structure of the battery device 10 according to an embodiment of this application is shown. Figure 2 As shown, the battery device 10 of this application embodiment may include a plurality of battery cells 20 to meet different power usage requirements. The shape of the battery cell 20 in this application embodiment can be set according to actual application. For example, the battery cell 20 can be as follows: Figure 2 The cylindrical shape shown, or it could be different. Figure 2 The embodiments shown may be cuboids or other shapes, but are not limited to these.

[0075] It should be understood that, such as Figure 2 As shown, the battery device 10 of this embodiment may further include a housing 11, which can be used to accommodate multiple battery cells 20. The housing 11 of this embodiment has a hollow interior, and the multiple battery cells 20 are accommodated within the housing 11. The housing 11 may include two parts, referred to herein as a first housing portion 111 and a second housing portion 112, which are fastened together. The shapes of the first housing portion 111 and the second housing portion 112 can be determined according to the shape of the components housed inside, for example, according to the shape of the combination of the multiple battery cells 20 housed inside. At least one of the first housing portion 111 and the second housing portion 112 has an opening. For example, as... Figure 2As shown, only one of the first housing portion 111 and the second housing portion 112 can be a hollow cuboid with an opening, while the other is plate-shaped to cover the opening. Taking the second housing portion 112 as a hollow cuboid with one opening, and the first housing portion 111 as a plate-shaped example, then the first housing portion 111 covers the opening of the second housing portion 112 to form a housing 11 with a closed chamber, which can be used to accommodate multiple battery cells 20. The multiple battery cells 20 are connected in parallel, series, or mixed and placed inside the housing 11 formed by the first housing portion 111 and the second housing portion 112 being fastened together.

[0076] For example, unlike Figure 2 As shown, the first box portion 111 and the second box portion 112 can both be hollow cuboids and each has one face as an opening. The openings of the first box portion 111 and the second box portion 112 are arranged opposite to each other, and the first box portion 111 and the second box portion 112 are interlocked to form a box 11 with a closed chamber, which can be used to accommodate multiple battery cells 20.

[0077] Figure 3 This illustration shows a top view of a plurality of battery cells 20 electrically connected within a battery device 10 according to an embodiment of this application. For example, the... Figure 3 It can be Figure 2 A top view of a partial structure of the battery device 10 shown. Figure 4 A schematic diagram of the structure of the first bus component 121 according to an embodiment of this application is shown. For example, the... Figure 4 The first bus component 121 shown can be Figure 3 An enlarged view of the first busbar component 121 included in the battery device 10 shown.

[0078] In this embodiment, the battery device 10 includes: a plurality of battery cell assemblies 200 connected in series, wherein a first battery cell assembly 210 of the plurality of battery cell assemblies includes a plurality of battery cells 20 connected in parallel; and a first busbar 121 for connecting the first battery cell 201 and a second battery cell 202 of the plurality of battery cells 20 in parallel, wherein the first busbar 121 includes a first connection portion 1211, a second connection portion 1212, and a safety portion 1213, wherein the first connection portion 1211 is used to connect to the first battery cell 201, the second connection portion 1212 is used to connect to the second battery cell 202, and the safety portion 1213 is located between the first connection portion 1211 and the second connection portion 1212, and the safety portion 1213 includes a current limiting element 12133.

[0079] It should be understood that the battery device 10 in this application embodiment may include a plurality of battery cell assemblies 200 connected in series, for example, Figure 3Each row in the table can represent a single battery cell assembly 200; each battery cell assembly 200 can include one or more battery cells 20, and the number of battery cells 20 included in different battery cell assemblies 200 can be the same or different. For example, as shown... Figure 3 As shown, for ease of explanation, this application embodiment takes the example where the number of battery cells 20 in the plurality of battery cell assemblies 200 included in the battery device 10 is the same, but this application embodiment is not limited to this.

[0080] The first battery cell assembly 210 in this application embodiment can be any one of the multiple battery cell assemblies 200 included in the battery device 10. Figure 5 This diagram illustrates the connection relationship between battery cells 20 within a battery device 10 according to an embodiment of this application. For example, Figure 5 It can be Figure 3 and Figure 4 A schematic diagram showing the connection relationship between multiple battery cells 20 in the battery device 10. Figure 6 A schematic diagram of the first battery cell assembly 210 according to an embodiment of this application is shown, for example, Figure 6 The first battery cell assembly 210 can be Figures 3 to 5 The battery device 10 shown includes any one of the battery cell assemblies 200. For example... Figure 6 As shown, the first battery cell assembly 210 may include multiple battery cells 20 connected in parallel, for example, Figure 6 Taking the first battery cell assembly 210, which includes five battery cells 20, as an example, the embodiments of this application are not limited to this.

[0081] like Figures 3 to 6 As shown, the plurality of battery cells 20 in the first battery cell assembly 210 includes a first battery cell 201 and a second battery cell 202. The first busbar 121 of the battery device 10 is used to connect the first battery cell 201 and the second battery cell 202 in parallel. The first battery cell 201 and the second battery cell 202 are any two battery cells in the first battery cell assembly 210 connected in parallel through the same first busbar 121. For example, Figure 6 Taking the middle battery cell 20 as the first battery cell 201 as an example, and the battery cell 20 on the right as the second battery cell 202 as an example.

[0082] Furthermore, the first busbar 121 can be used to connect the negative terminal of the first battery cell 201 and the negative terminal of the second battery cell 202, or it can be used to connect the positive terminal of the first battery cell 201 and the positive terminal of the second battery cell 202, so as to realize the parallel connection of the first battery cell 201 and the second battery cell 202. Specifically, for each pair of parallel battery cells 20 included in each battery cell assembly 200, the busbar for connecting the positive terminals of the two battery cells 20 can be the first busbar 121 of this application, and / or, the busbar for connecting the negative terminals of the two battery cells 20 can be the first busbar 121 of this application. In addition, in the battery device 10, all the busbars used to connect the positive terminals of the two parallel battery cells 20 can include one or more first busbars 121, and all the busbars used to connect the negative terminals of the two parallel battery cells 20 can also include one or more first busbars 121.

[0083] In some embodiments, for the same battery cell assembly 200, taking the first battery cell assembly 210 as an example, for the battery cells 20 connected in parallel within the first battery cell assembly 210, only the busbar for connecting the positive electrode can be set as the first busbar 121, or only the busbar for connecting the negative electrode can be set as the first busbar 121; or, all busbars for connecting the positive and negative electrodes can be set as the first busbar 121. The embodiments of this application are not limited to this.

[0084] Similarly, the configuration of the first busbar 121 can be the same or different for different battery cell assemblies 200. For example, if only the busbar for connecting the positive electrode is set as the first busbar 121 among the parallel battery cells 20 in the first battery cell assembly 210, then the configuration of the parallel battery cells 20 in other battery cell assemblies 200 can be the same as that of the first battery cell assembly 210, that is, only the busbar for connecting the positive electrode is set as the first busbar 121; or it can be different from the configuration of the first battery cell assembly 210, for example, only the busbar for connecting the negative electrode is set as the first busbar 121, or all the busbars for connecting the positive and negative electrodes are set as the first busbar 121. The embodiments of this application are not limited to this.

[0085] The first busbar component 121 of this application embodiment includes a first connecting part 1211, a second connecting part 1212 and a safety part 1213, wherein the first connecting part 1211 is used to connect with the first battery cell 201, and the second connecting part 1212 is used to connect with the second battery cell 202, so as to realize the parallel connection of the first battery cell 201 and the second battery cell 202.

[0086] In this embodiment, the safety unit 1213 is located between the first connecting part 1211 and the second connecting part 1212, and the safety unit 1213 includes a current limiting element 12133. Thus, as... Figure 6 As shown, in the event of thermal runaway of the first battery cell 201, even if the first battery cell 201 itself is approximately short-circuited, making it equivalent to a resistor with a very small resistance, the safety part 1213, which includes a current-limiting element 12133, is provided between the first battery cell 201 and the second battery cell 202 connected in parallel. This ensures that the current in the circuit between the first battery cell 201 and the second battery cell 202 will not be too large, reducing the risk of short circuit, thereby reducing the risk of thermal diffusion and improving the reliability of the battery device 10.

[0087] In this embodiment, the first busbar 121 with safety element 1213 can be used to achieve parallel connection between two battery cells 20. Specifically, the battery device 10 includes a third busbar 123 and a fourth busbar 124, wherein the third busbar 123 is used to connect the positive terminal of the first battery cell 201 and the positive terminal of the second battery cell 202, and the fourth busbar 124 is used to connect the negative terminal of the first battery cell 201 and the negative terminal of the second battery cell 202. At least one of the third busbar 123 and the fourth busbar 124 is the first busbar 121 with safety element 1213. Therefore, for any two battery cells 20 connected in parallel in the battery device 10 of this embodiment, any busbar used to achieve parallel connection can be provided with safety element 1213.

[0088] For example, Figure 3 Taking the third busbar 123 as an example, which is the first busbar 121 with a safety element 1213, while the fourth busbar 124 does not have a safety element 1213; for another example, different from Figure 3 As shown, the third bus component 123 may not have a safety part 1213, while the fourth bus component 124 is a first bus component 121 with a safety part 1213; for example, the third bus component 123 and the fourth bus component 124 may both be first bus components 121 with a safety part 1213, but the embodiments of this application are not limited to this.

[0089] It should be understood that when either the third busbar 123 or the fourth busbar 124 is a first busbar 121 with a safety element 1213, that is, when the safety element 1213 is provided in the third busbar 123 for connecting the positive electrode or in the fourth busbar 124 for connecting the negative electrode, the number of busbars with safety elements 1213 in the battery device 10 can be reduced, the complexity of the internal structure of the battery device 10 can be reduced, the processing and assembly of the battery device 10 can be facilitated, and the processing efficiency of the battery device 10 can be improved.

[0090] It should be understood that when both the third busbar 123 and the fourth busbar 124 are first busbar 121s with a safety element 1213, that is, when the safety element 1213 is provided in the third busbar 123 for connecting the positive electrode and the fourth busbar 124 for connecting the negative electrode, the reliability of the battery device 10 can be improved.

[0091] It should be understood that the safety part 1213 of the first busbar component 121 in this embodiment of the application is provided with a current limiting element 12133, and the resistance value of the current limiting element 12133 can be set according to the actual application. For example, the resistance value of the current limiting element 12133 can be set according to the number of parallel battery cells 20 included in the first battery cell assembly 210.

[0092] In some embodiments, the number of battery cells 20 connected in parallel in the first battery cell assembly 210 is less than or equal to 10. Setting the first battery cell assembly 210 to include two or more battery cells 20 connected in parallel can increase the capacity of the battery device 10. However, the parallel circuit is limited by the battery management system, charge / discharge control strategy, and safety factors, and the number of parallel battery cells 20 included in each battery cell assembly 200 should not be too large. Therefore, the number of parallel battery cells 20 can be set to be less than or equal to 10.

[0093] It should be understood that the resistance values ​​of the various current-limiting elements 12133 provided on the circuit formed by the first battery cell 201 and the second battery cell 202 in this application embodiment can be set according to actual applications. For example, in this application embodiment, at least one of the third busbar 123 and the fourth busbar 124 is a first busbar 121 provided with a safety part 1213.

[0094] In some embodiments, the resistance value of the current-limiting element 12133 included in the third busbar 123 and / or the fourth busbar 124 may be related to the position of the first battery cell 201 and the second battery cell 202 in the battery device 10. For example, as Figure 5As shown, taking the example that the number and resistance of the current-limiting elements 12133 among the parallel battery cells 20 in the same battery cell assembly 200 are the same, then for the first group of battery cell assemblies 200 connected to the positive output terminal of the battery device 10, the positive terminals of the multiple parallel battery cells 20 included in the first group of battery cell assemblies 200 can generally be connected as follows: Figure 5 The diagram shows that current limiting components 12133 are not provided, or are different from those shown. Figure 5 A low-resistance current-limiting element 12133 can also be placed between the positive terminals to reduce the impact on the positive output terminal of the battery device 10. Similarly, for the last group of battery cells 200 connected to the negative output terminal of the battery device 10, the negative terminals of the multiple parallel battery cells 20 included in the last group of battery cells 200 can generally be connected as follows: Figure 5 The diagram shows that current limiting components 12133 are not provided, or are different from those shown. Figure 5 A current-limiting element 12133 with low resistance can also be set between the negative terminals to reduce the impact on the negative output terminal of the battery device 10.

[0095] Specifically, such as Figure 5 As shown, if no current-limiting element 12133 is provided between the positive terminals of the multiple parallel battery cells 20 included in the first group of battery cell assembly 200, and similarly, no current-limiting element 12133 is provided between the negative terminals of the multiple parallel battery cells 20 included in the last group of battery cell assembly 200, then the resistance values ​​of the current-limiting elements 12133 provided between the negative terminals of the multiple parallel battery cells 20 included in the first group of battery cell assembly 200 and the current-limiting elements 12133 provided between the positive terminals of the multiple parallel battery cells 20 included in the last group of battery cell assembly 200 are relatively large, at least greater than the resistance values ​​of the current-limiting elements 12133 provided in the other battery cell assemblies 200, while the resistance values ​​of the current-limiting elements 12133 provided in the other battery cell assemblies 200 can be the same. Furthermore, according to... Figure 5 As shown in the connection relationship, for the second group of battery cells 200 which is adjacent to and connected in series with the first group of battery cells 200, the positive terminals of the multiple parallel battery cells 20 included therein can share the current limiting element 12133 with the negative terminals of the multiple parallel battery cells 20 included in the first group of battery cells 200; similarly, for the penultimate group of battery cells 200 which is adjacent to and connected in series with the last group of battery cells 200, the negative terminals of the multiple parallel battery cells 20 included therein can share the current limiting element 12133 with the positive terminals of the multiple parallel battery cells 20 included in the last group of battery cells 200.

[0096] Alternatively, if a current-limiting element 12133 is provided between the positive terminals of the multiple parallel battery cells 20 included in the first group of battery cell assembly 200, similarly, a current-limiting element 12133 can also be provided between the negative terminals of the multiple parallel battery cells 20 included in the last group of battery cell assembly 200. In this case, the resistance values ​​of the current-limiting elements 12133 provided between the positive terminals of the multiple parallel battery cells 20 included in the first group of battery cell assembly 200 and the current-limiting elements 12133 provided between the negative terminals of the multiple parallel battery cells 20 included in the last group of battery cell assembly 200 are relatively small, at least smaller than the resistance values ​​of the current-limiting elements 12133 provided in the other battery cell assemblies 200, while the resistance values ​​of the current-limiting elements 12133 provided in the other battery cell assemblies 200 can be the same.

[0097] In some embodiments, when at least one of the third busbar 123 and the fourth busbar 124 is a first busbar 121 equipped with a safety element 1213, the sum of the resistance values ​​R0 of the current-limiting elements 12133 included in the third busbar 123 and the fourth busbar 124 can be set according to the number of parallel battery cells 20 included in the first battery cell assembly 210. Specifically, if the third busbar 123 is a first busbar 121 with a safety element 1213, and the fourth busbar 124 is not equipped with a safety element 1213, then the sum of the resistance values ​​R0 in this embodiment represents the resistance value of the current-limiting element 12133 of the safety element 1213 of the third busbar 123; if the third busbar 123 is not equipped with a safety element 1213, and the fourth busbar 124 is a first busbar 121 with a safety element 1213, then the sum of the resistance values ​​R0 in this embodiment represents the resistance value of the first battery cell assembly 20. The resistance value of the current limiting element 12133 of the safety section 1213 of the four-bus component 124; if the third bus component 123 is a first bus component 121 with a safety section 1213, and the fourth bus component 124 is also a first bus component 121 with a safety section 1213, then the sum of resistance values ​​R0 in this embodiment represents the sum of the resistance value of the current limiting element 12133 of the safety section 1213 of the third bus component 123 and the resistance value of the current limiting element 12133 of the safety section 1213 of the fourth bus component 124.

[0098] In some embodiments, when the number of battery cells 20 connected in parallel in the first battery cell assembly 210 is in the range of [2, 10], the sum of resistance values ​​R0 in this embodiment satisfies: 0.46Ω ≤ R0 ≤ 24.36Ω. Limiting this sum of resistance values ​​R0 to be not too small, for example, typically setting the sum of resistance values ​​R0 ≥ 0.46Ω, then in the event of thermal runaway of the first battery cell 201, the short-circuit current in the circuit between the first battery cell 201 and the second battery cell 202 can be reduced, lowering the risk of thermal diffusion in the battery device 10 and improving the reliability of the battery device 10. Conversely, the sum of resistance values ​​R0 should not be too large either, for example, typically setting the sum of resistance values ​​R0 ≤ 24.36Ω, so that when any battery cell 20 in the circuit between the first battery cell 201 and the second battery cell 202 in parallel experiences self-discharge causing a voltage difference, the battery device 10 can balance the voltage difference through self-balancing in a short time, meeting the design requirements.

[0099] Furthermore, the sum of resistances R0 satisfies: 0.92Ω ≤ Rp ≤ 2.71Ω. Appropriately increasing this sum of resistances R0 can further reduce the short-circuit current in the circuit between the first battery cell 201 and the second battery cell 202 in the event of thermal runaway of the first battery cell 201, thus reducing the risk of thermal propagation in the battery device 10 and improving its reliability. Conversely, limiting the sum of resistances R0 to a less excessive amount can shorten the time required for the battery device 10 to self-balance the voltage difference caused by self-discharge in any of the parallel-connected battery cells 201 and 202, thereby improving the performance of the battery device 10.

[0100] It should be understood that the sum of the resistance values ​​R0 in the embodiments of this application can be any of the following values, or can be between any two of the following values: 0.46Ω, 0.48Ω, 0.5Ω, 0.55Ω, 0.6Ω, 0.65Ω, 0.7Ω, 0.75Ω, 0.8Ω, 0.85Ω, 0.9Ω, 0.92Ω, 0.95Ω, 0.98Ω, 1Ω, 1.2Ω, 1.4Ω, 1.6Ω, 1.8Ω, 2Ω, 2.3Ω, 2.5Ω, 2.71Ω, 3Ω, 5Ω, 7Ω, 9Ω, 10Ω, 13Ω, 15Ω, 18Ω, 20Ω, 21Ω, 22Ω, 23Ω, 24Ω, and 24.36Ω.

[0101] It should be understood that the resistance value of the current-limiting element 12133 of the safety section 1213 of the first busbar component 121 in this embodiment refers to the sum of the resistance values ​​of all current-limiting elements 12133 included in the safety section 1213. For ease of description, the following description will be based on the example of the safety section 1213 of the first busbar component 121 including one current-limiting element 12133.

[0102] In some embodiments, the current limiting element 12133 of this application includes at least one of the following: a capacitor, a bonded resistor, a resistance wire, and a diaphragm resistor, to facilitate fabrication. For example, the current limiting element 12133 is typically a bonded resistor.

[0103] It should be understood that the specific structure of the security unit 1213 in this application embodiment can be set according to actual application.

[0104] In some embodiments, the safety unit 1213 further includes a first connection structure 12131 and a second connection structure 12132. The first connection structure 12131 is used to connect the first connection portion 1211 and the current limiting element 12133, and the second connection structure 12132 is used to connect the second connection portion 1212 and the current limiting element 12133, so as to connect the first battery cell 201 and the second battery cell 202 in parallel. For example, as Figure 4 As shown, the first connection structure 12131 can be a connecting line; and / or, the second connection structure 12132 can be a connecting line to facilitate processing.

[0105] It should be understood that the number of first connecting structures 12131 in this embodiment can be set according to actual application, and the number of second connecting structures 12132 can also be set according to actual application. Furthermore, the number of first connecting structures 12131 can be the same as or different from the number of second connecting structures 12132. In addition, the number of both first connecting structures 12131 and second connecting structures 12132 should not be excessive to limit processing difficulty.

[0106] Figure 7 Another structural schematic diagram of the first bus component 121 according to an embodiment of this application is shown. For example, the... Figure 7 The first bus component 121 shown can be Figure 3 Another possible implementation of the first busbar component 121 included in the battery device 10 shown.

[0107] In some embodiments, the safety unit 1213 includes a plurality of first connection structures 12131 spaced apart; and / or, the safety unit 1213 includes a plurality of second connection structures 12132 spaced apart. By providing a plurality of first connection structures 12131, the connection strength between the first connection portion 1211 and the current limiting element 12133 can be improved; by providing a plurality of second connection structures 12132, the connection strength between the second connection portion 1212 and the current limiting element 12133 can be improved, thereby improving the stability of the safety unit 1213. For example, as... Figure 7 As shown, the safety unit 1213 may include three first connecting structures 12131 spaced apart and three second connecting structures 12132 spaced apart, which can improve the structural strength and stability and facilitate processing.

[0108] In some embodiments, the safety part 1213 is fixed to the first connecting part 1211 by welding; and / or, the safety part 1213 is fixed to the second connecting part 1212 by welding, to facilitate processing. For example, the first connecting part 1211 can be fixed to the first connecting structure 12131 by welding; as another example, the second connecting part 1212 can also be fixed to the second connecting structure 12132 by welding, which can both improve the connection strength and facilitate processing.

[0109] It should be understood that, since the size of the current-limiting element 12133 of the safety unit 1213 is usually smaller than the size of the first connecting part 1211 and the second connecting part 1212, for example, the thickness of the current-limiting element 12133 is usually smaller than the thickness of the first connecting part 1211 and the second connecting part 1212, the structural strength of the first connecting structure 12131 and the second connecting structure 12132 is limited. Therefore, during the use or transportation of the battery device 10, if a collision occurs, the safety unit 1213 may break between the first connecting part 1211 or between the safety unit 1213 and the second connecting part 1212, thereby reducing the reliability of the battery device 10 and causing a safety accident. Therefore, the first busbar component 121 of this embodiment may also be provided with a protective component 1214 to protect the safety unit 1213.

[0110] Figure 8 A schematic diagram of the structure of the first bus component 121 according to another embodiment of this application is shown; Figure 9 A top view of the first busbar component 121 according to another embodiment of this application is shown. Figure 9 It can be Figure 8 The diagram shows a top view of the first busbar component 121. Figure 8 and Figure 9 The first bus component 121 shown can be Figure 3 Another possible implementation of the first busbar component 121 included in the battery device 10 shown.

[0111] It should be understood that the first busbar component 121 in this embodiment further includes a protective component 1214, which protects the connection between the first connecting portion 1211 and the safety portion 1213, and / or the connection between the second connecting portion 1212 and the safety portion 1213. The protective component 1214 can improve the structural strength of the connection between the first connecting portion 1211 and the safety portion 1213, and also improve the structural strength of the connection between the second connecting portion 1212 and the safety portion 1213. This reduces the risk of breakage between the safety portion 1213 and the first connecting portion 1211 and / or between the safety portion 1213 and the second connecting portion 1212 during the use or transportation of the battery device 10, such as in the event of a collision, thereby improving the reliability of the battery device 10.

[0112] It should be understood that the specific location of the protective component 1214 in this application embodiment can be set according to actual application. In some embodiments, such as Figure 8 and Figure 9 As shown, the protective component 1214 at least covers the area of ​​the first connecting portion 1211 near the safety portion 1213 and the area of ​​the safety portion 1213 near the first connecting portion 1211. For example, the protective component 1214 can be used to cover the area of ​​the first connecting portion 1211 near the safety portion 1213 and the first connecting structure 12131 to improve the structural strength of the connection between the first connecting portion 1211 and the safety portion 1213.

[0113] In some embodiments, such as Figure 8 and Figure 9 As shown, the protective component 1214 at least covers the area of ​​the second connecting portion 1212 near the safety portion 1213 and the area of ​​the safety portion 1213 near the second connecting portion 1212. For example, the protective component 1214 can be used to cover the area of ​​the second connecting portion 1212 near the safety portion 1213 and the second connecting structure 12132 to improve the structural strength of the connection between the second connecting portion 1212 and the safety portion 1213.

[0114] Figure 10 A schematic diagram of the structure of the first busbar component 121 according to another embodiment of this application is shown; Figure 11 This paper shows a top view of the first busbar component 121 according to another embodiment of the present application. Figure 11 It can be Figure 10 The diagram shows a top view of the first busbar component 121. Figure 10 and Figure 11 The first bus component 121 shown can be Figure 3 Another possible implementation of the first busbar component 121 included in the battery device 10 shown.

[0115] In some embodiments, such as Figure 10 and Figure 11 As shown, the protective component 1214 covers the safety part 1213, the area of ​​the first connecting part 1211 near the safety part 1213, and the area of ​​the second connecting part 1212 near the safety part 1213. Unlike... Figure 8 and Figure 9 The first busbar component 121 shown, the protective component 1214 can also be used to cover the entire safety part 1213 to protect the safety part 1213.

[0116] It should be understood that the protective component 1214 covering the corresponding area in this embodiment of the application means that the protective component 1214 covers all or most of the surface of the corresponding area to improve the reliability of the structure.

[0117] In this embodiment, the protective component 1214 is fixed to at least one of the first connecting part 1211, the second connecting part 1212, and the safety part 1213 by hot melting and / or casting. That is, the protective component 1214 can be used by hot melting and / or casting to cover the corresponding area. The processing method is simple and easy to implement.

[0118] It should be understood that the material of the protective component 1214 in this application embodiment can be set according to the actual application. For example, the material of the protective component 1214 includes at least one of the following: polypropylene (PP), polyimide (PI), and meltable polytetrafluoroethylene (PFA), so as to facilitate processing and improve structural reliability and meet design requirements.

[0119] It should be understood that the first busbar component 121 in this application embodiment can be used to connect to the positive or negative terminal of the first battery cell 201, and the structure of the positive and negative terminals of the first battery cell 201 can be implemented in various ways. The structure of any battery cell 20 in this application embodiment will be described below with reference to the accompanying drawings.

[0120] Figure 12 A schematic diagram of the structure of a battery cell 20 according to an embodiment of this application is shown. For example, the battery cell 20 is shown. Figure 12 This can be a structural diagram of the battery cell 20 under normal use, and... Figure 12 The battery cell 20 shown can be any one of the battery cells 20 included in the battery device 10 of this application embodiment, such as the first battery cell 201 and the second battery cell 202. Figure 13 This paper shows a partial structural exploded view of the battery cell 20 according to an embodiment of the present application. For example, Figure 13 The battery cell 20 shown can be Figure 12 The diagram shows a partial structural exploded view of the battery cell 20. Figure 14 A partial cross-sectional schematic diagram of a battery cell 20 according to an embodiment of this application is shown. For example, the... Figure 14 The battery cell 20 shown can be Figure 12 and Figure 13 The battery cell 20 shown.

[0121] It should be understood that the battery cell 20 in this application embodiment can be a cylindrical battery cell, a prismatic battery cell, a pouch battery, or a battery cell of other shapes. Among them, the prismatic battery cell can include a prismatic battery cell, a blade-shaped battery cell, or other multi-prismatic battery cells, such as a hexagonal prismatic battery cell or an octagonal prismatic battery cell, and this application embodiment is not limited to these.

[0122] In this embodiment, the battery cell 20 includes a casing 21, which includes a first wall 2101. Specifically, the casing 21 can be a hollow polyhedral structure, and the casing 21 includes multiple walls, wherein the first wall 2101 can be any one of the walls of the casing 21. For example, as... Figures 12 to 14 As shown, taking a cylindrical battery cell 20 as an example, the outer casing 21 may include three walls. Here, the first wall 2101 is taken as the top wall of the cylinder, but the embodiments of this application are not limited to this.

[0123] In this embodiment, the outer casing 21 includes: a housing 211 with a hollow structure having an opening 2111; and a cover plate 212 for covering the opening 2111 to facilitate processing. Corresponding to different shapes of battery cells 20, the housing 211 of the battery cell 20 can have various shapes, such as a cylindrical or polygonal prism shape. The housing 211 can be a hollow structure with an opening 2111 at one or more ends. For example, if the housing 211 is a hollow structure with openings 2111 at opposite ends, two cover plates 212 can be provided, with each cover plate 212 covering the openings at both ends of the housing 211; Figures 12 to 14 As shown, if the housing 211 is a hollow structure with an opening 2111 at one end, the cover plate 212 can be set as one.

[0124] It should be understood that the cover plate 212 in this embodiment is used to cover the opening 2111 of the housing 211 to isolate the internal environment of the battery cell 20 from the external environment. The shape of the cover plate 212 can be adapted to the shape of the housing 211. For example, the housing 211 is a cuboid structure, and the cover plate 212 is a rectangular plate structure adapted to the housing 211; or, for example, ... Figures 12 to 14 As shown, the shell 211 is a cylindrical structure, and the cover plate 212 is a circular plate structure that is adapted to the shell 211.

[0125] The battery cell 20 also includes electrode terminals 214. In this embodiment, the electrode terminals 214 are used to electrically connect with the electrode assembly 22 inside the battery cell 20 to output the electrical energy of the battery cell 20. Furthermore, the battery cell 20 may include at least one electrode terminal 214, which includes at least one positive electrode terminal and / or at least one negative electrode terminal. If the battery cell 20 includes only at least one positive electrode terminal or only at least one negative electrode terminal, it can be electrically connected to the tabs 222 of the electrode assembly 22 through the housing 21, so that the housing 21 can output electrical energy in place of another electrode terminal with opposite polarity.

[0126] In this embodiment, taking the electrode terminal 214 disposed on the first wall 2101 as an example, the electrode terminal 214 is electrically insulated from the first wall 2101; wherein, the electrode terminal 214 can be a positive electrode terminal or a negative electrode terminal. The first wall 2101 can be any wall of the battery cell 20. In some embodiments, the cover plate 212 of this embodiment may include the first wall 2101 to facilitate processing.

[0127] Furthermore, the battery cell 20 may also include an insulating structure 24 disposed between the electrode terminal 214 and the first wall 2101. For example, taking the first battery cell 201 as an example, the insulating structure 24 of the first battery cell 201 is located between the electrode terminal 214 and the first wall 2101, so that the electrode terminal 214 and the first wall 2101 are electrically insulated. In addition, in the event of thermal runaway of the first battery cell 201, the insulating structure 24 of the first battery cell 201 can also be used to isolate the electrode terminal 214 and the first wall 2101, so that the electrode terminal 214 and the first wall 2101 are still electrically insulated, thereby reducing the risk of short circuit.

[0128] In some embodiments, the battery cell 20 further includes an electrode assembly 22, which is housed within the housing 21. Electrode terminals 214 are electrically connected to the first tab 2221 of the electrode assembly 22. In this battery cell 20, the electrode assembly 22 is the component where the electrochemical reaction occurs. Depending on actual usage requirements, the battery cell 20 may contain one or more electrode assemblies 22. The electrode assembly 22 can be cylindrical, cuboid, or similar. For example, if the electrode assembly 22 is cylindrical, the housing 211 can also be cylindrical; if the electrode assembly 22 is cuboid, the housing 211 can also be cuboid.

[0129] It should be understood that, such as Figures 12 to 14As shown, the electrode assembly 22 in this embodiment may include tabs 222 and an electrode body 221. The tabs 222 of the electrode assembly 22 may include a positive tab and a negative tab. The positive tab may be formed by stacking portions of a positive electrode sheet that are not coated with a positive active material, and the negative tab may be formed by stacking portions of a negative electrode sheet that are not coated with a negative active material. The electrode body 221 may be formed by stacking or winding positive and negative electrode sheets together.

[0130] The first tab 2221 of the electrode assembly 22 in this embodiment can be a positive tab or a negative tab. For example, if the first tab 2221 is a positive tab, then the electrode terminal electrically connected to the first tab 2221 is a positive electrode terminal. For example, the positive electrode terminal and the positive tab can be directly connected or indirectly connected. Conversely, if the first tab 2221 is a negative tab, then the electrode terminal electrically connected to the first tab 2221 is a negative electrode terminal. For example, the negative electrode terminal and the negative tab can be directly connected or indirectly connected. For example, the battery cell 20 further includes a connecting member 23 for electrically connecting the electrode terminal 214 and the first tab 2221 of the electrode assembly 22.

[0131] It should be understood that the aforementioned electrode terminal 214 can be any one of the electrode terminals 214 included in the battery cell 20. The battery cell 20 can also output electrical energy through the casing 21 instead of another electrode terminal with opposite polarity, or the battery cell 20 can also include another electrode terminal with opposite polarity.

[0132] In some embodiments, the second tab 2222 of the electrode assembly 22 is electrically connected to the first wall 2101, and the second tab 2222 has the opposite polarity to the first tab 2221. Specifically, as Figures 12 to 14 As shown, the battery cell 20 may include only one electrode terminal 214, and the first wall 2101 may serve as another electrode terminal with the opposite polarity to the electrode terminal 214, and be used for electrical connection with other battery cells 20. This simplifies the structure of the battery cell 20 and reduces the number of electrode terminals 214. For example, if the electrode terminal 214 is the positive electrode of the battery cell 20, then the first wall 2101 may be the negative electrode of the battery cell 20; or, if the electrode terminal 214 is the negative electrode of the battery cell 20, then the first wall 2101 may be the positive electrode of the battery cell 20.

[0133] In this embodiment of the application, the first connecting portion 1211 of the first busbar component 121 is used to connect to the first battery cell 201. Specifically, it can be used to connect to the positive or negative terminal of the first battery cell 201. For example, the first connecting portion 1211 is connected to the electrode terminal 214; or, the first connecting portion 1211 is connected to the first wall 2101.

[0134] Taking an example where the electrode terminals 214 of the first battery cell 201 and the second battery cell 202 are both positive, and the first wall 2101 of the first battery cell 201 and the first wall 2101 of the second battery cell 202 are both negative, the first busbar 121 can be used to connect the electrode terminals 214 of the first battery cell 201 and the second battery cell 202. That is, the first connecting part 1211 connects to the electrode terminals 214 of the first battery cell 201, and the second connecting part 1212 connects to the electrode terminals 214 of the second battery cell 202, so as to connect the first battery cell 201 and the second battery cell 202 in parallel. Alternatively, the first busbar component 121 can be used to connect the first wall 2101 of the first battery cell 201 and the first wall 2101 of the second battery cell 202, that is, the first connecting part 1211 connects to the first wall 2101 of the first battery cell 201 and the second connecting part 1212 connects to the first wall 2101 of the second battery cell 202, so as to connect the first battery cell 201 and the second battery cell 202 in parallel.

[0135] In some embodiments, with Figures 12 to 14 Unlike the battery cell 20 shown, the battery cell 20 may also have another electrode terminal with the opposite polarity to the electrode terminal 214 described above. In this embodiment, the first busbar component 121 can be connected to any one of the electrode terminals included in the battery cell 20. Furthermore, this other electrode terminal with the opposite polarity can be located on the first wall 2101 or another wall to achieve electrical connection between the battery cell 20 and other battery cells 20. Moreover, the structure of this other electrode terminal can be the same as that of the electrode terminal 214 in this embodiment for ease of manufacturing. For simplicity, further details are omitted here.

[0136] In some embodiments, the battery device 10 further includes a second busbar 122, which connects a first battery cell 201 and a third battery cell 203 in series, wherein the third battery cell 203 and the first battery cell 201 belong to different battery cell assemblies 200. The second busbar 122 can be used to achieve a series connection between different battery cell assemblies 200. For example, the second busbar 122 can be used to connect the positive terminal of the first battery cell 201 and the negative terminal of the third battery cell 203, or it can be used to connect the negative terminal of the first battery cell 201 and the positive terminal of the third battery cell 203.

[0137] It should be understood that for any battery cell 20, taking the first battery cell 201 as an example, the first battery cell 201 can be connected to a first busbar 121 to achieve parallel connection with the second battery cell 202; the first battery cell 201 can also be connected to a second busbar 122 to achieve series connection with the third battery cell 203. The first busbar 121 and the second busbar 122 can be separate structures or integrated structures, and the embodiments of this application are not limited thereto.

[0138] According to some embodiments of this application, this application also provides an electrical device including the battery device 10 described in any of the above embodiments, and the battery device 10 is used to provide electrical energy to the electrical device.

[0139] The electrical equipment can be any of the aforementioned devices or systems that utilize the battery device 10.

[0140] According to some embodiments of this application, see Figures 3 to 6 This application provides a battery device 10, including: a plurality of battery cell assemblies 200 connected in series, wherein a first battery cell assembly 210 of the plurality of battery cell assemblies includes a plurality of battery cells 20 connected in parallel; a first busbar 121 for connecting the first battery cell 201 and the second battery cell 202 of the plurality of battery cells 20 in parallel, the first busbar 121 including a first connection portion 1211, a second connection portion 1212 and a safety portion 1213, the first connection portion 1211 being connected to the first battery cell 201, the second connection portion 1212 being connected to the second battery cell 202, the safety portion 1213 being located between the first connection portion 1211 and the second connection portion 1212, and the safety portion 1213 including a current limiting element 12133.

[0141] The number of battery cells 20 connected in parallel in the first battery cell assembly 210 is less than or equal to 10. The battery device includes a third busbar 123 and a fourth busbar 124. The third busbar 123 is used to connect the positive terminal of the first battery cell 201 and the positive terminal of the second battery cell 202. The fourth busbar 124 is used to connect the negative terminal of the first battery cell 201 and the negative terminal of the second battery cell 202. At least one of the third busbar 123 and the fourth busbar 124 is a first busbar 121 provided with a safety element 1213. The sum of the resistances R0 of the current limiting elements 12133 included in the third busbar 123 and the fourth busbar 124 satisfies: 0.46Ω ≤ R0 ≤ 24.36Ω. Further, the sum of the resistances R0 satisfies: 0.92Ω ≤ Rp ≤ 2.71Ω.

[0142] The first battery cell 201 includes: a housing 21, which includes a first wall 2101; an electrode terminal 214 disposed on the first wall 2101 and electrically insulated from the first wall 2101; and an electrode assembly 22 housed within the housing 21. The electrode terminal 214 is electrically connected to a first tab 2221 of the electrode assembly 22. A second tab 2222 of the electrode assembly 22 is electrically connected to the first wall 2101, and the second tab 2222 has the opposite polarity to the first tab 2221. A first connecting portion 1211 is connected to the electrode terminal 214; or, the first connecting portion 1211 is connected to the first wall 2101.

[0143] The safety unit 1213 further includes a first connecting structure 12131 and a second connecting structure 12132. The first connecting structure 12131 is used to connect the first connecting part 1211 and the current limiting element 12133, and the second connecting structure 12132 is used to connect the second connecting part 1212 and the current limiting element 12133. The safety unit 1213 includes a plurality of first connecting structures 12131 spaced apart; and / or, the safety unit 1213 includes a plurality of second connecting structures 12132 spaced apart.

[0144] The first busbar component 121 further includes a protective component 1214, which protects the connection between the first connecting portion 1211 and the safety portion 1213, and / or protects the connection between the second connecting portion 1212 and the safety portion 1213. The protective component 1214 covers at least: the area of ​​the first connecting portion 1211 near the safety portion 1213 and the area of ​​the safety portion 1213 near the first connecting portion 1211, and / or, the area of ​​the second connecting portion 1212 near the safety portion 1213 and the area of ​​the safety portion 1213 near the second connecting portion 1212. The protective component 1214 covers the safety portion 1213, the area of ​​the first connecting portion 1211 near the safety portion 1213, and the area of ​​the second connecting portion 1212 near the safety portion 1213.

[0145] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and not to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. These modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application, and they should all be covered within the scope of the claims and specification of this application. In particular, as long as there is no structural conflict, the various technical features mentioned in the embodiments can be combined in any way. This application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A battery device, characterized by, include: A series of battery cell assemblies (200), wherein the first battery cell assembly (210) of the series of battery cell assemblies comprises a series of battery cells (20) connected in parallel; A first busbar (121) is used to connect a first battery cell (201) and a second battery cell (202) in parallel among the plurality of battery cells (20). The first busbar (121) includes a first connecting part (1211), a second connecting part (1212), and a safety part (1213). The first connecting part (1211) is used to connect to the first battery cell (201), the second connecting part (1212) is used to connect to the second battery cell (202), and the safety part (1213) is located between the first connecting part (1211) and the second connecting part (1212). The safety part (1213) includes a current limiting element (12133).

2. The battery device according to claim 1, characterized by The battery device includes a third busbar (123) and a fourth busbar (124). The third busbar (123) is used to connect the positive electrode of the first battery cell (201) and the positive electrode of the second battery cell (202). The fourth busbar (124) is used to connect the negative electrode of the first battery cell (201) and the negative electrode of the second battery cell (202). At least one of the third busbar (123) and the fourth busbar (124) is the first busbar (121) that is provided with the safety unit (1213).

3. The battery device of claim 2, wherein, The number of battery cells (20) connected in parallel in the first battery cell assembly (210) is less than or equal to 10.

4. The battery device of claim 3, wherein The sum of the resistance values ​​R0 of the current limiting element (12133) included in the third bus component (123) and the fourth bus component (124) satisfies: 0.46Ω≤R0≤24.36Ω.

5. The battery device of claim 4, wherein, The sum of the resistance values ​​R0 satisfies: 0.92Ω≤Rp≤2.71Ω.

6. The battery device of claim 1, wherein The first battery cell (201) includes: The outer casing (21) includes a first wall (2101); An electrode terminal (214) is disposed on the first wall (2101), and the electrode terminal (214) is electrically insulated from the first wall (2101); Electrode assembly (22), which is housed within the housing (21), wherein the electrode terminal (214) is electrically connected to the first tab (2221) of the electrode assembly (22).

7. The battery device of claim 6, wherein The first connecting part (1211) is connected to the electrode terminal (214).

8. The battery device of claim 6, wherein, The second tab (2222) of the electrode assembly (22) is electrically connected to the first wall (2101), and the second tab (2222) has the opposite polarity to the first tab (2221). The first connecting part (1211) is connected to the first wall (2101).

9. The battery device of claim 1, wherein, The safety unit (1213) further includes a first connection structure (12131) and a second connection structure (12132), wherein the first connection structure (12131) is used to connect the first connection part (1211) and the current limiting element (12133), and the second connection structure (12132) is used to connect the second connection part (1212) and the current limiting element (12133).

10. The battery device according to claim 9, characterized in that, The safety unit (1213) includes a plurality of the first connection structures (12131) spaced apart; and / or, The safety unit (1213) includes a plurality of second connection structures (12132) spaced apart.

11. The battery device of claim 1, wherein The first bus component (121) further includes: A protective component (1214) is provided to protect the connection between the first connecting part (1211) and the safety part (1213), and / or to protect the connection between the second connecting part (1212) and the safety part (1213).

12. The battery device of claim 11, wherein, The protective component (1214) covers at least: the region of the first connecting portion (1211) near the safety portion (1213) and the region of the safety portion (1213) near the first connecting portion (1211), and / or, the region of the second connecting portion (1212) near the safety portion (1213) and the region of the safety portion (1213) near the second connecting portion (1212).

13. The battery device of claim 11, wherein, The protective component (1214) covers the safety part (1213), the area of ​​the first connecting part (1211) near the safety part (1213), and the area of ​​the second connecting part (1212) near the safety part (1213).

14. The battery device of claim 11, wherein, The protective component (1214) is fixed to at least one of the first connecting part (1211), the second connecting part (1212), and the safety part (1213) by hot melting and / or casting processes.

15. The battery device of claim 11, wherein, The material of the protective component (1214) includes at least one of the following: polypropylene, polyimide and fusible polytetrafluoroethylene.

16. The battery device according to any one of claims 1 to 15, characterized by, The current limiting element (12133) includes at least one of the following: a capacitor, a bonding resistor, a resistance wire, and a diaphragm resistor.

17. The battery device of any one of claims 1 to 15, wherein, The safety part (1213) is fixed to the first connecting part (1211) by welding; and / or, The safety part (1213) and the second connecting part (1212) are fixed together by welding.

18. The battery device of any one of claims 1 to 15, wherein, The battery device also includes: The second busbar component (122) is used to connect the first battery cell (201) and the third battery cell (203) in series, wherein the third battery cell (203) and the first battery cell (201) belong to different battery cell assemblies (200).

19. An electrical device, comprising: include: A battery device, comprising the battery device as claimed in any one of claims 1 to 18, the battery device being used to provide electrical energy to the electrical equipment.

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