Battery and electrical equipment

Abstract

The present application provides a battery and an electrical device. The battery includes: a plurality of cylindrical battery cells, each battery cell including a housing, an electrode assembly, and an electrode terminal. The housing is used to accommodate the electrode assembly, and the housing includes a cylinder and a cover body connected to the cylinder. The electrode assembly has a first tab and a second tab. The first tab is electrically connected to the electrode terminal, and the second tab is electrically connected to the cover body; a current collecting member for electrically connecting at least two battery cells. The current collecting member has a first connecting portion, and the first connecting portion is welded to the cover body of one of the plurality of battery cells to form a welding area. The maximum bridging angle θ of the welding area in the circumferential direction of the battery cell, the diameter D of the battery cell, and the height H of the battery cell in its own axial direction should satisfy: 50×D / H ≤ θ ≤ 270. The present application can ensure the electrical connection requirements between battery cells and improve the safety performance of the battery.

Description

Technical Field

[0001] The present application relates to the field of batteries, and particularly to a battery and an electrical device using the same. Background Art

[0002] Energy conservation and emission reduction are the keys to the sustainable development of the automotive industry. Electric vehicles have become an important part of the sustainable development of the automotive industry due to their advantages of energy conservation and environmental protection. For electric vehicles, battery technology is an important factor related to their development.

[0003] In existing batteries, a plurality of battery cells need to be electrically connected. How to reliably meet the electrical connection requirements between the battery cells is a technical problem to be solved urgently. Summary of the Invention

[0004] In view of the above problems, the present application provides a battery and an electrical device using the same, in which the electrical connection performance between the battery cells is reliable and the safety performance of the battery is high.

[0005] In a first aspect, the present application provides a battery, comprising: a plurality of cylindrical battery cells, each battery cell including a housing, an electrode assembly, and an electrode terminal, the housing being used to accommodate the electrode assembly, the housing including a cylindrical body and a cover body connected to the cylindrical body, the electrode assembly having a first tab and a second tab, the first tab being electrically connected to the electrode terminal, and the second tab being electrically connected to the cover body; a current collecting member for electrically connecting at least two battery cells, the current collecting member having a first connection portion and a second connection portion, the first connection portion being welded to the cover body of one of the plurality of battery cells to form a welding area, and the second connection portion being electrically connected to another one of the plurality of battery cells.

[0006] The battery provided by the embodiment of the present application includes a plurality of cylindrical battery cells and a current collecting member. Each battery cell includes a housing, an electrode assembly, and an electrode terminal. The first tab of the electrode assembly is electrically connected to the electrode terminal and the second tab is electrically connected to the cover body of the housing. The current collecting member has a first connection portion and a second connection portion, and can be welded to one of the plurality of battery cells through the first connection portion to form a welding area, and be electrically connected to another one of the plurality of battery cells through the second connection portion, so as to realize the series or parallel connection between the battery cells, meet the electrical connection requirements, and improve the connection performance and the safety performance of the battery through the connection methods of the first connection portion and the second connection portion respectively.

[0007] In some embodiments, the maximum bridging angle θ of the welding area in the circumferential direction of the battery cell, the diameter D of the battery cell, and the height H of the battery cell in its own axial direction should satisfy: 50°×D / H ≤ θ ≤ 270°.

[0008] By ensuring that the maximum span angle θ of the welding zone in the circumferential direction of the battery cell, the diameter D of the battery cell, and the height H of the battery cell in its own axial direction meet 50°×D / H≤θ≤270°, the span angle of the welding zone in the battery cell can be moderate, which can not only meet the overcurrent requirements, but also avoid excessive overcurrent temperature, thereby improving the overall safety performance of the battery.

[0009] In some embodiments, the maximum cross-over angle θ, the diameter D of the battery cell, and the height H of the battery cell body in its own axial direction should satisfy: 80°×D / H≤θ≤180°.

[0010] When θ ≥ 180°, the busbar assembly is prone to short circuits during assembly and loading during battery grouping. By ensuring that the maximum cross-connection angle θ, the diameter D of the battery cell, and the axial height H of the battery cell body satisfy 80° × D / H ≤ θ ≤ 180°, while meeting the electrical connection requirements between battery cells, the busbar assembly can be effectively prevented from short circuiting due to the large maximum cross-connection angle during battery grouping, thereby improving the overall safety of the battery.

[0011] In some embodiments, the actual overcurrent resistance R of the housing and the full-rated overcurrent resistance R1 satisfy R / R1≤1.1, wherein the full-rated overcurrent resistance R1 is the overcurrent resistance value of the housing when the maximum cross-angle of the welding area in the circumferential direction of the battery cell is 360°.

[0012] Through the above arrangement, the outer shell of the battery cell can meet the overcurrent resistance requirement, avoid high temperature rise, and improve the safety performance of the battery.

[0013] In some embodiments, the first connecting portion has two opposite free ends, and a minimum distance M between the two free ends is greater than a diameter d of the electrode terminal.

[0014] With the above arrangement, when the maximum cross-connection angle θ of the welding zone in the circumferential direction of the battery cell is greater than 180° and less than 270°, the probability of short circuit of the busbar component during assembly can be reduced, thereby improving the safety performance of the battery.

[0015] In some embodiments, the effective welding area S between the first connecting portion and the cover, the diameter D of the battery cell, and the height H of the battery cell in its own axial direction should satisfy: S ≥ 3 × 10 -5 ×mm -1 ×H×D 2 .

[0016] Through the above arrangement, the effective welding area size can be guaranteed, thereby avoiding insufficient flow area due to insufficient effective welding area between the first connecting portion and the cover body, reducing the flow temperature rise, and improving the safety performance of the battery.

[0017] In some embodiments, the effective welding area S, the diameter D of the battery cell, and the height H of the battery cell in its own axial direction should satisfy: S≥6×10 -5 ×mm -1 ×H×D 2 。

[0018] Through the above settings, on the basis of satisfying the maximum circumferential bridging angle θ of the welding area on the battery cell, the effective welding area S can be further increased, the over-current capacity can be improved, and the over-current temperature can be reduced.

[0019] In some embodiments, the busbar component is provided with a fusing part, which is used to fuse when the current flowing through the busbar component exceeds a preset threshold. The fusing part is provided with a notch, and the maximum distance r between the center of the battery cell connected to the first connecting part of the side wall enclosing the notch should satisfy: r < D / 2 + g, where: g is the minimum distance between the two battery cells connected by the first connecting part and the second connecting part.

[0020] Through the above settings, the position of the fusing part is close to the welding area, where the heat is concentrated. When the battery is overloaded, the fusing part can quickly fuse and cut off the current, and at the same time, no secondary lap short circuit will be caused after fusing.

[0021] In some embodiments, the notch is in a closed hole shape or a U-shaped groove shape.

[0022] By making the notch in a closed hole shape or a U-shaped groove shape, it is beneficial to the formation of the notch, and at the same time, the performance requirements of the fusing part can be guaranteed.

[0023] In some embodiments, the notch is located between the first connecting part and the second connecting part; or, the notch is formed by a depression from the surface of the first connecting part away from the second connecting part to the side where the second connecting part is located.

[0024] Through the above settings, the diversification of the notch can be realized, which is suitable for different structural forms of busbar components.

[0025] In some embodiments, the first connecting part is an axisymmetric structure as a whole.

[0026] Through the above settings, it is beneficial to the connection between the first connecting part and the cover body. At the same time, it can make the current flowing through the first connecting part keep the same path when flowing to the two free ends in its circumference, and retain the uniformity of current transmission.

[0027] In some embodiments, the first connecting part is in the shape of an arc-shaped plate structure, and a continuous linear welding is performed between the first connecting part and the cover body.

[0028] By making the first connecting part in the form of an arc-shaped plate structure, the welding requirements between the connecting part and the cover of the corresponding battery cell can be ensured, which is conducive to avoiding the electrode terminals of the battery cell connected thereto, ensuring the electrical connection requirements for the battery cell, and at the same time reducing the short-circuit risk.

[0029] In some embodiments, the first connecting part includes at least two wiring blocks, and each wiring block is welded to the cover respectively.

[0030] Through the above arrangement, it is conducive to the forming of the busbar component and the connection requirements with the battery cell, and further meets the electrical connection requirements with the battery cell.

[0031] In some embodiments, the cylindrical body has an opening at one end facing away from the cover, the battery cell further includes a cover for closing the opening, the first tab and the second tab are respectively arranged at two ends of the electrode assembly along its own axial direction, an electrode lead-out hole is provided on the cover, the electrode terminal is arranged in the electrode lead-out hole and is electrically connected to the first tab, and the second tab is electrically connected.

[0032] Through the above arrangement, the cover of the battery cell and the electrode terminal are on the same side and carry charges with different polarities, which is conducive to the busbar component to electrically connect each battery cell.

[0033] In a second aspect, the present application provides an electrical device, and the electrical device includes the above-mentioned battery, and the battery is used to provide electrical energy.

[0034] The above description is only an overview of the technical solution of the present application. In order to be able to understand the technical means of the present application more clearly, it can be implemented according to the content of the specification. And in order to make the above and other purposes, features and advantages of the present application more obvious and understandable, the specific embodiments of the present application are given below. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] To make the objectives, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly described below with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are some, but not all, of the embodiments of the present application. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present application without creative efforts shall fall within the protection scope of the present application.

[0036] Figure 1 A schematic structural diagram of a vehicle provided for some embodiments of the present application;

[0037] Figure 2 An exploded view of a battery provided for some embodiments of the present application;

[0038] Figure 3 For Figure 2Schematic diagram of the partial structure of the battery shown;

[0039] Figure 4 Cross-sectional view of a battery cell provided by some embodiments of the present application;

[0040] Figure 5 Schematic diagram of the cooperation between a battery cell and a busbar component provided by some embodiments of the present application;

[0041] Figure 6 For Figure 5 Top view of the structure shown;

[0042] Figure 7 Schematic diagram of the structure of a busbar component provided by some embodiments of the present application;

[0043] Figure 8 Schematic diagram of the structure of a busbar component provided by other embodiments of the present application;

[0044] Figure 9 Top view of two battery cells connected by a busbar component;

[0045] Figure 10 Schematic diagram of the structure of a busbar component provided by still other embodiments of the present application;

[0046] Figure 11 Schematic diagram of the structure of a busbar component provided by yet other embodiments of the present application.

[0047] Figure 12 Schematic diagram of the structure of the cooperation between a battery cell and a busbar component provided by some embodiments of the present application;

[0048] The reference numerals in the specific embodiments are as follows:

[0049] 1 - Vehicle; 2 - Battery; 3 - Controller; 4 - Motor; 5 - Box; 51 - First box part; 52 - Second box part; 53 - Accommodating space; 6 - Battery module;

[0050] 7 - Battery cell;

[0051] 10 - Electrode assembly; 11 - Main body part; 12 - First tab; 13 - Second tab;

[0052] 20 - Outer shell; 21 - Cylinder; 22 - Cover body;

[0053] 30 - Electrode terminal;

[0054] 40 - Sealing cover;

[0055] 8 - Busbar component; 81 - First connection part; 811 - Wiring block; 81a - Free end; 82 - Second connection part; 83 - Fusing part; 831 - Notch; 84 - Welding area;

[0056] X - axial direction; Y - circumferential direction. Detailed implementation manners

[0057] To make the objectives, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly described below with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are some, but not all, of the embodiments of the present application. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present application without making creative efforts shall fall within the scope of protection of the present application.

[0058] Unless otherwise defined, all technical and scientific terms used in the present application have the same meaning as commonly understood by those skilled in the technical field to which the present application belongs; the terms used in the description of the present application in the specification are only for the purpose of describing specific embodiments and are not intended to limit the present application; the terms "including" and "having" and any variations thereof in the specification and claims of the present application and the above drawings are intended to cover non - exclusive inclusion. The terms "first", "second", etc. in the specification and claims of the present application or the above drawings are used to distinguish different objects and are not used to describe a specific order or primary - secondary relationship.

[0059] Referring to "embodiments" in the present application means that specific features, structures or characteristics described in connection with the embodiments can be included in at least one embodiment of the present application. The appearance of this phrase in various positions in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment mutually exclusive with other embodiments.

[0060] In the description of the present application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", "coupled", "attached" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected, or indirectly connected through an intermediate medium, and can be the communication inside two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to specific situations.

[0061] The term "and / or" in the present application is only a description of the association relationship of associated objects, indicating that three relationships can 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 the present application generally represents an "or" relationship between the associated objects before and after.

[0062] In the embodiments of the present application, the same reference numerals denote the same components, and for the sake of brevity, in different embodiments, the detailed description of the same components is omitted. It should be understood that the thickness, length, width and other dimensions of various components in the embodiments of the present application shown in the drawings, as well as the overall thickness, length, width and other dimensions of the integrated device are only exemplary descriptions and should not constitute any limitation to the present application.

[0063] The term "a plurality of" as used in the present application means two or more (including two).

[0064] In the present application, the battery cell may include a lithium-ion secondary battery cell, a lithium-ion primary battery cell, a lithium-sulfur battery cell, a sodium-lithium-ion battery cell, a sodium-ion battery cell, a magnesium-ion battery cell, etc., and the embodiments of the present application are not limited thereto.

[0065] The present application provides a single physical module with higher voltage and capacity. For example, the battery mentioned in the present application may include a battery module, a battery pack, etc. A battery generally includes a box body for encapsulating one or more battery cells. The box body can prevent liquids or other foreign objects from affecting the charging or discharging of the battery cells.

[0066] The inventors have noticed that the voltage and capacity of a single battery cell are limited. If multiple battery cells included in a battery are independently arranged, there are multiple connection terminals, which is not conducive to the use of electric energy. If multiple battery cells are electrically connected, integration can be achieved to form a battery module with higher voltage and capacity, ensuring the use demand of electric energy. Then, how to reliably electrically connect multiple battery cells is a technical problem to be solved urgently.

[0067] In view of this, the embodiments of the present application provide a battery, including a plurality of cylindrical battery cells and a current collecting component. Each battery cell includes a housing, an electrode assembly, and an electrode terminal. The housing is used to accommodate the electrode assembly. The housing includes a cylinder body and a cover body connected to the cylinder body. The electrode assembly has a first tab and a second tab. The first tab is electrically connected to the electrode terminal, and the second tab is electrically connected to the cover body. The current collecting component is used to electrically connect at least two battery cells. The current collecting component has a first connection portion and a second connection portion. The first connection portion is welded to the cover body of one of the plurality of battery cells to form a welding area, and the second connection portion is electrically connected to another one of the plurality of battery cells. By providing the current collecting component and making the current collecting component have a first connection portion and a second connection portion, the first connection portion can be welded to one of the plurality of battery cells to form a welding area, and the second connection portion can be electrically connected to another one of the plurality of battery cells, so as to realize the series or parallel connection between the battery cells, meet the electrical connection requirements, and through the connection methods of the first connection portion and the second connection portion respectively, the connection performance is reliable, and the safety performance of the battery is improved.

[0068] The technical solutions described in the embodiments of the present application are applicable to electrical devices using batteries.

[0069] The electrical device can be a vehicle, a mobile phone, a portable device, a laptop, a ship, a spacecraft, an electric toy, an electric tool, etc. The vehicle can be a fuel vehicle, a gas vehicle or a new energy vehicle. The new energy vehicle can be a pure electric vehicle, a hybrid vehicle or an extended-range electric vehicle, etc.; the spacecraft includes an airplane, a rocket, a space shuttle, a spaceship, etc.; the electric toy includes a fixed or mobile electric toy, for example, a game console, an electric vehicle toy, an electric ship toy, an electric airplane toy, etc.; the electric tool includes a metal cutting electric tool, a grinding electric tool, an assembly electric tool and a railway electric tool, for example, an electric drill, an electric grinding wheel, an electric wrench, an electric screwdriver, a hammer drill, an impact drill, a concrete vibrator, a planer, etc. The embodiments of the present application do not impose special restrictions on the above electrical devices.

[0070] For the convenience of description, the following embodiments will take the electrical device as a vehicle as an example for illustration.

[0071] Figure 1 It is a schematic structural diagram of a vehicle provided by some embodiments of the present application. As Figure 1 shown, a battery 2 is disposed inside the vehicle 1. The battery 2 can be disposed at the bottom, head or tail of the vehicle 1. The battery 2 can be used for power supply of the vehicle 1. For example, the battery 2 can be used as the operating power source of the vehicle 1.

[0072] The vehicle 1 may further include a controller 3 and a motor 4. The controller 3 is used to control the battery 2 to supply power to the motor 4. For example, it is used for the working power requirements during the start, navigation and driving of the vehicle 1.

[0073] In some embodiments of the present application, the battery 2 can not only be used as the operating power source of the vehicle 1, but also be used as the driving power source of the vehicle 1, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1.

[0074] Figure 2 It is an explosion schematic diagram of a battery provided by some embodiments of the present application, Figure 3 is Figure 2 a partial structural schematic diagram of the battery shown, Figure 4 is a cross-sectional view of a battery cell, Figure 5 It is a schematic diagram of the cooperation between a battery cell and a busbar component provided by some embodiments of the present application, Figure 6 is Figure 5 a top view of the structure shown, Figure 7 It is a schematic structural diagram of a busbar component provided by some embodiments of the present application.

[0075] As Figures 2 to 7As shown, the battery 2 may include a box body 5, cylindrical battery cells 7, and a current collecting component 8. Each battery cell 7 includes a housing 20, an electrode assembly 10, and an electrode terminal 30. The housing 20 is used to accommodate the electrode assembly 10. The housing 20 includes a cylindrical body 21 and a cover body 22 connected to the cylindrical body 21. The electrode assembly 10 has a first tab 12 and a second tab 13. The first tab 12 is electrically connected to the electrode terminal 30, and the second tab 13 is electrically connected to the cover body 22. The current collecting component 8 is used to electrically connect at least two battery cells 7. The current collecting component 8 has a first connection portion 81 and a second connection portion 82. The first connection portion 81 is welded to the cover body 22 of one of the multiple battery cells 7 to form a welding area 84, and the second connection portion 82 is electrically connected to another one of the multiple battery cells 7.

[0076] Optionally, the box body 5 is used to accommodate the battery cells 7, and the box body 5 can have various structures. In some embodiments, the box body 5 may include a first box body portion 51 and a second box body portion 52. The first box body portion 51 and the second box body portion 52 cover each other, and the first box body portion 51 and the second box body portion 52 jointly define an accommodation space 53 for accommodating the battery cells 7. The second box body portion 52 can be a hollow structure with one end open, and the first box body portion 51 is a plate-like structure. The first box body portion 51 covers the open side of the second box body portion 52 to form the box body 5 with the accommodation space 53; both the first box body portion 51 and the second box body portion 52 can also be hollow structures with one side open, and the open side of the first box body portion 51 covers the open side of the second box body portion 52 to form the box body 5 with the accommodation space 53. Of course, the first box body portion 51 and the second box body portion 52 can have various shapes, such as a cylinder, a cuboid, etc.

[0077] To improve the sealing performance after the connection between the first box body portion 51 and the second box body portion 52, a sealing member, such as sealant, sealing ring, etc., can also be provided between the first box body portion 51 and the second box body portion 52.

[0078] Assuming that the first box body portion 51 covers the top of the second box body portion 52, the first box body portion 51 can also be called the upper box cover, and the second box body portion 52 can also be called the lower box body.

[0079] Optionally, in the battery 2, there can be multiple battery cells 7. If there are multiple battery cells 7, the multiple battery cells 7 can be connected in series, parallel, or in a hybrid connection. A hybrid connection means that there are both series and parallel connections among the multiple battery cells 7. The multiple battery cells 7 can be directly connected in series, parallel, or in a hybrid connection together. Of course, it is also possible that multiple battery cells 7 are first connected in series, parallel, or in a hybrid connection to form a battery module 6, and then multiple battery modules 6 are connected in series, parallel, or in a hybrid connection to form a whole and are accommodated in the box body 5.

[0080] In some embodiments, such as Figure 2 、 Figure 3As shown, there are multiple battery cells 7, which are first connected in series, in parallel, or in series to form a battery module 6. The multiple battery modules 6 are then connected in series, in parallel, or in series to form a whole.

[0081] Multiple battery cells 7 in the battery module 6 can be electrically connected via a busbar 8 to achieve parallel, series, or mixed connection of multiple battery cells 7 in the battery module 6. There can be one or more busbars 8, each of which is used to electrically connect at least two battery cells 7.

[0082] Optionally, the electrode assembly 10 of the battery cell 7 may include a first electrode sheet, a second electrode sheet, and a separator, wherein the separator is used to separate the first electrode sheet from the second electrode sheet. The first electrode sheet and the second electrode sheet have opposite polarities. In other words, one of the first electrode sheet and the second electrode sheet is a positive electrode sheet, and the other of the first electrode sheet and the second electrode sheet is a negative electrode sheet.

[0083] The first pole piece, the second pole piece and the separator are all strip-shaped structures, and the first pole piece, the second pole piece and the separator are wound together around the central axis A to form a wound structure. The wound structure can be a cylindrical structure.

[0084] like Figure 4 As shown, from the appearance of the electrode assembly 10, the electrode assembly 10 includes a main body 11, a first electrode tab 12, and a second electrode tab 13. The first electrode tab 12 and the second electrode tab 13 protrude from the main body 11. The first electrode tab 12 is the portion of the first electrode sheet not coated with the active material layer, and the second electrode tab 13 is the portion of the second electrode sheet not coated with the active material layer.

[0085] The first electrode tab 12 and the second electrode tab 13 may extend from the same side of the main body 11 or from opposite sides. For example, the first electrode tab 12 and the second electrode tab 13 are respectively disposed on either side of the main body 11 along the axial direction X of the battery cell 7. In other words, the first electrode tab 12 and the second electrode tab 13 are respectively disposed at both ends of the electrode assembly 10 along the axial direction X. The first electrode tab 12 is located at the end of the electrode assembly 10 facing the cover 22, and the second electrode tab 13 is located at the end of the electrode assembly 10 facing away from the cover 22.

[0086] Optionally, the outer shell 20 is a hollow structure, forming a space within it for accommodating the electrode assembly 10. The shape of the outer shell 20 can be determined based on the specific shape of the electrode assembly 10. For example, if the electrode assembly 10 is cylindrical, a cylindrical outer shell 20 can be used. Alternatively, both the electrode assembly 10 and the outer shell 20 can be cylindrical; accordingly, the barrel 21 is a cylinder, and the cover 22 is a circular plate-like structure.

[0087] The cover body 22 and the cylinder body 21 can be integrally formed structures, that is, the outer shell 20 is an integrally formed component. Of course, the cover body 22 and the cylinder body 21 can also be two separately provided components, and then connected together by means such as welding, riveting, and bonding.

[0088] Optionally, an electrode lead-out hole 221 can be provided on the cover body 22. The electrode lead-out hole 221 penetrates through the cover body 22 to facilitate the extraction of electrical energy in the electrode assembly 10 to the outside of the outer shell 20. Exemplarily, the electrode lead-out hole 221 penetrates through the cover body 22 along the axial direction X.

[0089] Optionally, the electrode terminal 30 is used to cooperate with the electrode lead-out hole 221 to cover the electrode lead-out hole 221. The electrode terminal 30 can extend into the electrode lead-out hole 221 or not. The electrode terminal 30 is fixed to the cover body 22. The electrode terminal 30 can be integrally fixed on the outside of the cover body 22 or extend into the interior of the outer shell 20 through the electrode lead-out hole 221.

[0090] Optionally, the outer shell 20 can be positively charged or negatively charged.

[0091] Optionally, the busbar component 8 can be used to electrically connect two battery cells 7 or more than two battery cells 7.

[0092] Optionally, the busbar component 8 can connect at least two battery cells 7 in series, in parallel, or in a series-parallel hybrid connection.

[0093] Optionally, the welding area 84 can be understood as the area where the busbar component 8 is connected to the cover body 22 through solder.

[0094] Optionally, the first connecting portion 81 can be arc-shaped or can be set in a two-point or multi-point form.

[0095] Optionally, the second connecting portion 82 and the first connecting portion 81 can be of an integral structure form. Of course, a split structure can also be adopted and connected by means such as welding.

[0096] Optionally, the structural form of the second connecting portion 82 can be the same as that of the first connecting portion 81. At this time, the second connecting portion 82 can be used to electrically connect to the cover body 22 of another one of the multiple battery cells 7 to achieve parallel connection between the battery cells 7. Of course, in some embodiments, the shape of the second connecting portion 82 can also be made to match that of the electrode terminal 30 to electrically connect it to the electrode terminal 30 of another one of the multiple battery cells 7 to achieve series connection between the battery cells 7.

[0097] The battery 2 provided by the embodiment of the present application has a busbar component 8 with a first connection part 81 and a second connection part 82. The first connection part 81 can be welded to one of the plurality of battery cells to form a welding area 84, and the second connection part 82 can be electrically connected to another one of the plurality of battery cells 7, so as to realize the series or parallel connection between the battery cells 7, meet the electrical connection requirements, and through the connection methods of the first connection part 81 and the second connection part 82 respectively, the connection performance is reliable, and the safety performance of the battery is improved.

[0098] Optionally, the inventor also noticed that when the busbar component 8 is electrically connected to the cover 22 of the battery cell 7, if the span of the welding area 84 along the circumferential direction Y of the battery cell 7 is too small, it will cause the resistance of the current flowing into the outer shell 20 in the welding area 84 to be too large, and the corresponding overcurrent temperature rise will be too large, affecting the safety of the battery 2. If the span of the welding area 84 along the circumferential direction Y of the battery cell 7 is too large, it will make the busbar component 8 prone to short circuit during assembly and feeding, affecting the safety of the battery 2. Therefore, how to set the maximum bridging angle of the welding area 84 between the busbar component 8 and the cover 22 of the battery cell 7 is also one of the problems to be solved urgently in the battery field.

[0099] In order to solve the above technical problems, in some embodiments, the maximum bridging angle θ of the welding area 84 along the circumferential direction Y of the battery cell 7, the diameter D of the battery cell 7, and the height H of the battery cell 7 in its own axial direction X should satisfy: 50°×D / H≤θ≤270°.

[0100] Optionally, the maximum bridging angle θ of the welding area 84 along the circumferential direction Y of the battery cell 7 can be understood as that the positive projection profile of the area where the busbar component 8 is connected to the cover 22 through solder along the axial direction X of the battery cell 7 has two edge positions along the circumferential direction Y, and the included angle between the connection line between one edge position and the center of the battery cell 7 connected by the first connection part 81 and the connection line between the other edge position and the center of the battery cell 7.

[0101] Optionally, the diameter D of the battery cell 7 can be understood as the radial dimension of the annular outer wall surface of the cylinder body 21 of the battery cell 7.

[0102] Optionally, the height H of the battery cell 7 in its own axial direction X can be understood as the vertical distance between the surface of the cover 22 of the battery cell 7 facing away from the electrode assembly 10 and the bottom surface of the battery cell 7.

[0103] Optionally, the first connection part 81 has a predetermined span along the circumferential direction Y of the battery cell 7, and the welding area 84 can be continuously arranged or intermittently arranged along the circumferential direction Y of the battery cell 7.

[0104] The battery 2 provided by the embodiment of the present application can make the spanning angle of the welding area 84 on the battery cell 7 moderate by limiting that the maximum spanning angle θ of the welding area 84 in the circumferential direction Y of the battery cell 7, the diameter D of the battery cell 7, and the height H of the battery cell 7 in its own axial direction X satisfy 50°×D / H≤θ≤270°. It can not only meet the overcurrent requirement, but also avoid too high overcurrent temperature, and improve the overall safety performance of the battery.

[0105] In some embodiments, the maximum spanning angle θ, the diameter D of the battery cell 7, and the height H of the main body of the battery cell 7 in its own axial direction X should satisfy: 80°×D / H≤θ≤180°.

[0106] When θ≥180℃, during the grouping process of the battery 2, the busbar component 8 is prone to short - circuit during assembly and feeding. By making the maximum spanning angle θ, the diameter D of the battery cell 7, and the height H of the battery cell 7 in its own axial direction X satisfy 80°×D / H≤θ≤180°, on the basis of meeting the electrical connection requirements between the battery cells 7, it can effectively avoid the short - circuit phenomenon of the busbar component 8 caused by the large maximum spanning angle θ during the grouping process of the battery 2, and improve the overall safety performance of the battery.

[0107] In some embodiments, the cylinder body 21 has an opening at one end facing away from the cover body 22. The battery cell 7 further includes a cover 40 for closing the opening. The first ear 12 and the second ear 13 are respectively arranged at both ends of the electrode assembly 10 along its own axial direction X. An electrode lead - out hole 221 is provided on the cover body 22, and the electrode terminal 30 is arranged in the electrode lead - out hole 221 and is electrically connected to the first ear 12. The second ear 13 is electrically connected to the outer shell 20 through the cover 40.

[0108] The cover 40 can be located inside the cylinder body 21 and is connected to the cylinder body 21 by welding. At this time, the height H of the battery cell 7 in its own axial direction X can be understood as the height dimension of the outer shell 20 in the axial direction X.

[0109] Certainly, the cover 40 can at least partially protrude from the cylinder body 21 in the axial direction X and is connected to the cylinder body 21 by welding. At this time, the height H of the battery cell 7 in its own axial direction X can be understood as the vertical distance between the surface of the cover 40 facing away from the cover body 22 and the surface of the cover body 22 facing away from the cover 40.

[0110] The second ear 13 can be in contact with and electrically connected to the cover 40. Since the cover 40 is connected to the cylinder body 21 of the outer shell 20, the electrical connection between the second ear 13 and the outer shell 20 can be realized, making the cover 40 of the outer shell 20 charged.

[0111] The battery 2 provided by the embodiment of the present application, through the above settings, enables the cover 22 of the battery cell 7 and the electrode terminal 30 to be on the same side and carry charges with different polarities, which is beneficial for the busbar component 8 to electrically connect each battery cell 7.

[0112] In some embodiments, the actual overcurrent resistance R of the housing 20 and the full-load overcurrent resistance R1 satisfy R / R1 ≤ 1.1, where the full-load overcurrent resistance R1 is the overcurrent resistance value of the housing 20 when the maximum bridging angle of the welding area 84 in the circumferential direction Y of the battery cell 7 is 360°.

[0113] Optionally, the full-load overcurrent resistance R1 is the overcurrent resistance value of the housing 20 when the maximum bridging angle of the welding area 84 in the circumferential direction Y of the battery cell 7 is 360°, which can be understood as the overcurrent resistance value of the housing 20 when the welding area 84 is a complete ring.

[0114] Optionally, the ratio of the actual overcurrent resistance R of the housing 20 to the full-load overcurrent resistance R1 can be any value less than 1.1, including the end value of 1.1. Optionally, the ratio of the actual overcurrent resistance R of the housing 20 to the full-load overcurrent resistance R1 can be less than or equal to 1.05.

[0115] The battery provided by the embodiment of the present application, by making the actual overcurrent resistance R of the housing 20 and the full-load overcurrent resistance R1 satisfy R / R1 ≤ 1.1, through the above settings, can ensure the overcurrent resistance requirement at the connection between the housing 20 of the battery cell 7 and the busbar component 8, avoid a relatively high temperature rise, and improve the safety performance of the battery.

[0116] Referring to Table 1 below, it can be seen from Table 1 that in Embodiment 1, Embodiment 2, and Embodiment 5, 50°×D / H ≤ θ, and the ratio of the actual overcurrent resistance R of their housing 20 to the full-load overcurrent resistance R1 can be less than or equal to 1.05, while in Embodiment 3 and Embodiment 4, 50°×D / H ≥ θ, and the ratio of the actual overcurrent resistance R of their housing 20 to the full-load overcurrent resistance R1 is greater than 1.1, resulting in an increased overcurrent resistance at the connection between the housing 20 and the busbar component 8, posing a safety hazard.

[0117] Therefore, when 50°×D / H ≤ θ, it can make R / R1 ≤ 1.05, which is beneficial to improving the safety performance of the battery.

[0118] Table 1:

[0119]

[0120] As Figures 5 to 7 shown, in some embodiments, for the battery provided by the embodiment of the present application, the first connecting portion 81 is an axisymmetric structure as a whole.

[0121] It can be understood that when the orthographic projection of the first connecting portion 81 on the cover body 22 is folded along a straight line, the parts on both sides of the straight line can coincide with each other.

[0122] Through the above arrangement, it is beneficial to the connection between the first connecting portion 81 and the cover body 22. At the same time, it can make the paths of the current flowing through the first connecting portion 81 on both sides in its circumferential direction Y remain the same, ensuring the uniformity of current transmission.

[0123] Figure 8 It is a schematic structural diagram of the busbar component 8 according to other embodiments of the present application.

[0124] Such as Figure 7 、 Figure 8 As shown, in some embodiments, the first connecting portion 81 may further include at least two wiring blocks 811, and each wiring block 811 is respectively welded to the cover body 22.

[0125] Optionally, as Figure 7 shown, the first connecting portion 81 may include two wiring blocks 811. Of course, as Figure 8 shown, the first connecting portion 81 may also include three or even more wiring blocks 811.

[0126] Optionally, the wiring block 811 of the first connecting portion 81 may be polygonal, and exemplarily, it may be rectangular. The shapes of the wiring blocks 811 may be the same or different.

[0127] Optionally, when the first connecting portion 81 includes at least two wiring blocks 811, the included angle formed by the welding positions of the two outermost wiring blocks 811 and the cover body 22 at the ends far from each other and the center connection line of the battery cell 7 is the maximum bridging angle θ of the welding area 84 in the circumferential direction Y of the battery cell 7.

[0128] By including at least two wiring blocks 811 in the first connecting portion 81, and each wiring block 811 is respectively welded to the cover body 22, it is beneficial to the forming of the busbar component 8 and the connection requirements with the battery cell 7, and further meets the electrical connection requirements with the battery cell 7.

[0129] Figure 9 It is a top view of two battery cells connected by the busbar component.

[0130] Such as Figures 5 to 9As shown, in some embodiments, the busbar component 8 is provided with a fusing portion 83. The fusing portion 83 is configured to fuse when the current flowing through the busbar component 8 exceeds a preset threshold. The fusing portion 83 is provided with a notch 831. The maximum distance r between the center of the battery cell 7 connected to the first connection portion 81 of the busbar component 8 and the side wall enclosing the notch 831 should satisfy: r < D / 2 + g, where: g is the minimum distance between the two battery cells 7 connected to the first connection portion 81 and the second connection portion 82.

[0131] Optionally, the notch 831 of the fusing portion 83 can be a grooved shape with an opening, and of course, it can also be a closed ring shape.

[0132] Optionally, the minimum distance between the two battery cells 7 connected to the first connection portion 81 and the second connection portion 82 can be understood as the minimum distance between the outer wall surfaces of the cylinders 21 of the two battery cells 7 connected to the first connection portion 81 and the second connection portion 82.

[0133] Referring to Table 2 below, by limiting r < D / 2 + g, the position of the fusing portion 83 is close to the welding area 84, where the heat is concentrated. When the battery is overloaded with current, the fusing portion 83 can quickly fuse to cut off the current, and at the same time, no secondary lap short circuit will be caused after fusing.

[0134] Table 2:

[0135]

[0136] As an optional embodiment, the notch 831 is in a closed hole shape or a U-shaped groove shape.

[0137] Optionally, the notch 831 can also be in a closed hole shape. When it is in a closed hole shape, the notch 831 can be a circular, elliptical or polygonal hole shape.

[0138] Optionally, when the notch 831 is in a closed hole shape, the notch 831 can be located between the first connection portion 81 and the second connection portion 82.

[0139] Optionally, the notch 831 can be in a U-shaped groove shape. When the notch 831 is in a U-shaped groove shape, the notch 831 can be connected and recessed in the width direction of the busbar component 8. Of course, the notch 831 can also be recessed in the length direction of the busbar component 8, such as the arrangement direction of the first connection portion 81 and the second connection portion 82.

[0140] By making the notch 831 in a closed hole shape or a U-shaped groove shape, it is beneficial to the formation of the notch 831 during processing, and at the same time, the performance requirements of the fusing portion 83 can be ensured.

[0141] In some embodiments, the notch 831 is located between the first connection portion 81 and the second connection portion 82.

[0142] It can be understood that in each of the above embodiments, the first connecting portion 81 includes at least two wiring blocks 811, and each wiring block 811 is welded to the cover body 22 respectively. This is an optional embodiment.

[0143] Figure 10 Schematic diagram of the busbar component 8 of some other embodiments of the present application.

[0144] As Figure 10 shown, in some embodiments, the first connecting portion 81 is in the form of an arc-shaped plate structure, and continuous linear welding is performed between the first connecting portion 81 and the cover body 22.

[0145] The first connecting portion 81 extends along the circumferential direction Y of the battery cell 7, and the extension dimension of the first connecting portion 81 extending in the circumferential direction Y can be set according to the value range of the maximum bridging angle θ of the welding area 84 in the circumferential direction Y of the battery cell 7.

[0146] By making the first connecting portion 81 in the form of an arc-shaped plate structure, the welding requirements between the first connecting portion 81 and the cover body 22 of the corresponding battery cell 7 can be ensured, which is beneficial to avoiding the electrode terminal 30 of the battery cell 7 connected thereto, ensuring the electrical connection requirements of the battery cell 7, and at the same time reducing the short-circuit risk.

[0147] Figure 11 Schematic diagram of the busbar component 8 of still some other embodiments of the present application.

[0148] As Figure 11 shown, the notch 831 can also be formed by recessing from the surface of the first connecting portion 81 facing away from the second connecting portion 82 toward the side where the second connecting portion 82 is located.

[0149] Through the above settings, the diversification of the notch 831 can be realized, which is applicable to different structural forms of the busbar component 8.

[0150] As Figures 6 to 11 shown, in some embodiments, the first connecting portion 81 has two opposite free ends 81a, and the minimum distance M between the two free ends 81a is greater than the diameter d of the electrode terminal 30.

[0151] Optionally, the two free ends 81a can be understood as two end positions in the circumferential direction Y, and the vertical distance between the surfaces of the two free ends 81a facing each other can be understood as the minimum distance M.

[0152] When the electrode terminal 30 is cylindrical, the diameter d can be understood as the diameter of the annular outer peripheral surface. When the electrode terminal 30 is polygonal, its diameter d can be understood as the diameter of the circumscribed circle or the inscribed circle of the polygonal contour.

[0153] The battery provided in the embodiment of the present application reduces the probability of short circuit of the busbar component 8 during assembly, thereby improving the safety performance of the battery, by ensuring that the minimum distance M between the two free ends 81a of the first connecting portion 81 is greater than the diameter d of the electrode terminal 30. This allows the maximum cross-connection angle θ of the welding area 84 in the circumferential direction Y of the battery cell 7 to be greater than 180° and less than 270°.

[0154] Figure 12 This is a schematic structural diagram of the cooperation between battery cells and busbar components in some embodiments of the present application.

[0155] like Figures 6 to 12 As shown, in some embodiments, the effective welding area S between the first connecting portion 81 and the cover 22, the diameter D of the battery cell 7, and the height H of the battery cell 7 in its own axial direction X should satisfy: S ≥ 3 × 10 -5 ×mm -1 ×H×D 2 .

[0156] Optionally, the first connecting portion 81 is an arc-shaped plate-shaped structure, and the effective welding area S between the first connecting portion 81 and the cover body 22 can be understood as the product of the effective weld width w and the weld length.

[0157] Optionally, when the first connecting portion 81 includes a structural form of at least two wiring blocks 811, the effective welding area S between the first connecting portion 81 and the cover body 22 can be understood as the sum of the effective welding areas between all wiring blocks 811 and the cover body 22, and the effective welding area between each wiring block 811 and the cover body 22 is the product of the effective weld width w and the weld length.

[0158] Through the above arrangement, the effective welding area size can be guaranteed, thereby avoiding insufficient flow area due to insufficient effective welding area between the first connecting portion 81 and the cover body 22, reducing the flow temperature rise, and improving the safety performance of the battery.

[0159] In some embodiments, the effective welding area S, the diameter D of the battery cell 7, and the height H of the battery cell 7 in its own axial direction X should satisfy: S ≥ 6 × 10 -5 ×mm -1 ×H×D 2 .

[0160] As shown in Table 3 below, when the effective weld area S is small, the temperature at the weld mark increases, affecting battery safety. Therefore, the above configuration further increases the effective weld area S, while meeting the maximum crossover angle θ of the weld zone 84 in the circumferential direction Y of the battery cell 7, thereby increasing the flow rate and reducing the flow temperature.

[0161] Table 3:

[0162]

[0163] According to some embodiments of the present application, the present application further provides an electrical device, including the battery described in any of the above solutions, and the battery is used to provide electrical energy for the electrical device.

[0164] The electrical device may be any of the aforementioned devices or systems that apply the battery.

[0165] Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements on some or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application, and they should all be covered by the scope of the claims and the specification of the present application. In particular, as long as there is no structural conflict, the technical features mentioned in each embodiment can be combined in any way. The present application is not limited to the specific embodiments disclosed in the text, but includes all technical solutions falling within the scope of the claims.

Claims

1. A battery, characterized in that, Comprising: A plurality of cylindrical battery cells, each of the battery cells including a housing, an electrode assembly, and an electrode terminal, the housing for accommodating the electrode assembly, the housing including a cylindrical body and a cover body connected to the cylindrical body, the electrode assembly having a first tab and a second tab, the first tab being electrically connected to the electrode terminal, and the second tab being electrically connected to the cover body; A current collecting member for electrically connecting at least two of the battery cells, the current collecting member having a first connection portion and a second connection portion, the first connection portion being welded to the cover body of one of the plurality of battery cells to form a welding area, and the second connection portion being electrically connected to the housing or the electrode terminal of another one of the plurality of battery cells; The maximum bridging angle of the welding area in the circumferential direction of the battery cell and the diameter D of the battery cell and the height H of the battery cell in its own axial direction should satisfy: 50°×D / H ≤ ≤ 270°. The orthographic projection profile of the welding area in the axial direction of the battery cell has two edge positions along the circumference, and the maximum bridging angle is the angle between the connection line between the center of the battery cell connected to the first connection part and one of the edge positions and the connection line between the center of the battery cell and the other edge position; The current collecting member is provided with a fusing portion for fusing when the current flowing through the current collecting member exceeds a preset threshold, and the fusing portion is provided with a notch.

2. The battery according to claim 1, wherein The maximum bridging angle and the diameter D of the battery cell and the height H of the battery cell body in its own axial direction should satisfy: 80°×D / H ≤ ≤ 180°.

3. The battery according to claim 1, characterized in that, The first connection portion has two opposite free ends, and the minimum distance M between the two free ends is greater than the diameter d of the electrode terminal.

4. The battery according to any one of claims 1 to 3, characterized in that The maximum distance r between the side wall enclosing the notch and the center of the battery cell connected to the first connection portion of the current collecting member should satisfy: r < D / 2 + g, where: g is the minimum distance between the two battery cells connected by the first connection portion and the second connection portion.

5. The battery according to claim 4, characterized in that, The notch is in a closed hole shape or a U-shaped groove shape.

6. The battery according to claim 4, characterized in that, The notch is located between the first connection portion and the second connection portion; Alternatively, the notch is formed by a depression from the surface of the first connection portion facing away from the second connection portion towards the side where the second connection portion is located.

7. The battery according to any one of claims 1 to 3, characterized in that, The first connection portion is an axially symmetric structure as a whole.

8. The battery according to claim 7, characterized in that, The first connection portion is in the shape of an arc-shaped plate structure, and the second connection portion is continuously linearly welded to the cover body; Alternatively, the first connection portion includes at least two connection blocks, and each of the connection blocks is welded to the cover body.

9. The battery according to any one of claims 1 to 3, characterized in that, The cylindrical body has an opening at one end facing away from the cover body, the battery cell further includes a sealing cover for closing the opening, the first tab and the second tab are respectively disposed at both ends of the electrode assembly along its own axial direction, the cover body is provided with an electrode lead-out hole, the electrode terminal is disposed in the electrode lead-out hole and is electrically connected to the first tab, and the second tab is electrically connected to the housing through the sealing cover.

10. An electrical device, characterized in that, The electrical device includes the battery according to any one of claims 1 to 9, and the battery is used to provide electrical energy.

Images