Battery unit, battery module, battery and electric device

Abstract

The embodiment of the utility model provides a battery unit, a battery module, a battery and a power utilization device, the battery unit is used in the battery module, the battery module comprises a plurality of electrically connected battery units, each battery unit comprises a shell, a plurality of soft package battery monomers and a top cover, the shell is provided with an accommodating cavity, and the shell is also provided with an opening communicated with the accommodating cavity; the plurality of soft package battery monomers are positioned in the accommodating cavity; the top cover comprises a body part, the body part covers the opening of the shell and is provided with a pressure relief hole penetrating through the body part in the first direction, and the first direction is parallel to the arrangement direction from the soft package battery monomers to the top cover. The reliability of the battery can be improved.

Description

Technical Field

[0001] The present application relates to the field of battery technology, and more specifically, to a battery cell, a battery module, a battery, and an electrical device. Background Art

[0002] Battery monomers are widely used in electronic devices, such as mobile phones, laptop computers, electric vehicles, electric cars, electric airplanes, electric ships, electric toy cars, electric toy ships, electric toy airplanes and electric tools, etc.

[0003] In the development of battery technology, how to improve battery reliability is a research direction in battery technology. Utility Model Content

[0004] The present application provides a battery cell, a battery module, a battery and an electrical device, which can improve the reliability of the battery.

[0005] An embodiment of the present application provides a battery cell, which is used in a battery module. The battery module includes a plurality of electrically connected battery cells, the battery cell including a shell, a plurality of soft-pack battery cells and a top cover, the shell having a accommodating cavity, the shell also having an opening connected to the accommodating cavity; the plurality of soft-pack battery cells are located in the accommodating cavity; the top cover includes a main body, the main body covers the opening of the shell, and has a pressure relief hole passing through the main body along a first direction, and the first direction is parallel to the arrangement direction of the soft-pack battery cells to the top cover.

[0006] In the above technical solution, the battery module is split into multiple battery cells, and the battery cells are configured to include a shell and a top cover, and a pressure relief hole is provided on the top cover. In this way, when the soft-pack battery cell in the shell undergoes thermal runaway, the high-temperature gas will be directed from the pressure relief hole of the top cover, and will not be randomly ejected, thereby reducing the impact on the soft-pack battery cells in other battery cells and improving the reliability of the battery. Moreover, by reasonably setting the first direction in the battery module, the high-temperature gas can further reduce the impact on the soft-pack battery cells of other battery cells, further improving the reliability of the battery. In addition, since the shell and the top cover form a relatively closed space, they protect themselves and further reduce the risk of thermal runaway in other battery cells.

[0007] In some embodiments, there are multiple pressure relief holes, and the multiple pressure relief holes are arranged at intervals.

[0008] In the above technical solution, a plurality of pressure relief holes are arranged at intervals, which can improve the structural strength of the pressure relief holes, thereby improving the reliability of the battery unit.

[0009] In some embodiments, the top cover further includes a weak structure, which is connected to a side of the main body away from the accommodating cavity and covers the pressure relief hole, and the weak structure is configured to be opened by high-temperature gas when thermal runaway occurs in the soft-pack battery cell.

[0010] In the above technical solution, a weak structure is provided. Under normal working temperature, the weak structure covers the pressure relief hole, providing a relatively stable working environment for the soft-pack battery cell and reducing the entry of dust, particles, etc. into the accommodation cavity. When thermal runaway occurs, the high-temperature gas can break through the weak structure to relieve pressure.

[0011] In some embodiments, the weak structure is an insulating member.

[0012] In the above technical solution, the weak structure is set as an insulating part, which reduces the risk of short circuiting other battery cells when being opened by high-temperature gas, thereby improving the reliability of the battery cells.

[0013] In some embodiments, the end of the shell surrounds the outer peripheral side of the main body, and the battery unit also includes a fastener, which is arranged around one end of the shell close to the main body and fixes the shell to the main body.

[0014] In the above technical solution, fasteners are used for connection, which is convenient for operation and has high production efficiency.

[0015] In some embodiments, a step structure is formed on at least a portion of the outer peripheral side of the main body, and the step structure includes a first step surface, a second step surface, and a third step surface connected in sequence, the second step surface intersects with the first direction, the first step surface is located on the side of the third step surface close to the soft-pack battery cell, the shell abuts against the first step surface, and the shell and the fastener are limited to the second step surface.

[0016] In the above technical solution, a step structure is formed on at least part of the outer peripheral side of the main body, so that the second step surface can form a limiting effect on the fastener, reducing the risk of the fastener falling off the shell, and at the same time, it is also convenient to position the shell and facilitate assembly.

[0017] In some embodiments, the shell includes a shell body and a bottom cover, and the shell body has a first state before molding and a second state after molding. In the first state, the shell body includes a first end and a second end opposite to each other in a surrounding direction, and the first end and the second end can be separated from each other to form an opening for the soft-pack battery cell to enter the shell body; in the second state, the shell body surrounds the soft-pack battery cell, the first end and the second end are connected, the top cover covers one end of the shell body in the first direction, and the bottom cover covers the other end of the shell body in the first direction.

[0018] In the above technical solution, the shell is configured to include a shell body and a bottom cover, and the shell body can form an opening in the first state. In this way, when the soft-pack battery cell is assembled into the shell, the opening is opened to a suitable size and the soft-pack battery cell is placed in the shell body. The operation is convenient and the assembly efficiency is high.

[0019] In some embodiments, the shell body is an integrally formed piece.

[0020] In the above technical solution, the shell body is set as an integrally formed part, which can reduce the connection process and improve production efficiency. In addition, when the shell body is subjected to force to form an opening, the integrally formed shell body can have good toughness and strength, reducing the possibility of damage due to force.

[0021] In some embodiments, the bottom cover is an insulating member.

[0022] In the above technical solution, the bottom cover is set as an insulating member, which can reduce material costs and can be connected by convenient connection methods such as bonding.

[0023] In some embodiments, a plurality of soft-pack battery cells include a first battery cell and a second battery cell arranged along a second direction, the first battery cell includes a first positive terminal and a first negative terminal arranged along a third direction, the second battery cell includes a second positive terminal and a second negative terminal arranged along the third direction, the top cover also includes a busbar, the busbar is arranged on a side of the main body facing the accommodating cavity, the first positive terminal and the second negative terminal are respectively fitted and connected to opposite sides of the busbar along the second direction and are electrically connected through the busbar, and the second direction and the third direction intersect with the first direction in pairs.

[0024] In the above technical solution, a busbar is provided, and the first positive terminal and the second negative terminal are directly attached to the busbar, so that the first positive terminal and the second negative terminal do not need to be electrically connected by bending and welding, that is, the electrical connection between the soft-pack battery cells is achieved in a relatively straight state, thereby improving the problem of bending causing the ear glue of the soft-pack battery cell to be damaged and then causing leakage of the soft-pack battery cell, and reducing the defective rate of the battery unit.

[0025] In some embodiments, the top cover also includes a first output electrode and a second output electrode arranged along the second direction, the first output electrode and the second output electrode are embedded in the main body at intervals, and extend from a side of the main body facing the accommodating cavity to a side of the main body facing away from the accommodating cavity, a portion of the first output electrode close to the accommodating cavity is conductively connected to the first negative terminal, and a portion of the second output electrode close to the accommodating cavity is conductively connected to the second positive terminal.

[0026] In the above technical solution, the first output electrode and the second output electrode are arranged through the main body, which can save the setting of the adapter component, facilitate the connection with the first negative terminal and the second positive terminal, and save the connection process.

[0027] In some embodiments, the body portion is an insulating member.

[0028] In the above technical solution, the main body is set as an insulating part, which can reduce the risk of short circuit between the first output electrode, the second output electrode, the bus bar and the top cover, improve the reliability of the battery unit, and also omit the insulation process between the first output electrode, the second output electrode, the bus bar and the top cover.

[0029] In some embodiments, the top cover also includes an insulating component, which is arranged on a side of the main body facing the accommodating cavity, and the first output electrode and the second output electrode are respectively arranged on opposite sides of the insulating component along the second direction. The insulating component extends toward the accommodating cavity and electrically isolates the first negative terminal and the second positive terminal.

[0030] In the above technical solution, an insulating component is provided to insulate the first negative terminal and the second positive terminal, thereby reducing the probability of contact between the two, reducing the risk of short circuit, and improving the reliability of the battery unit.

[0031] In a second aspect, an embodiment of the present application further provides a battery module, comprising the above-mentioned battery unit.

[0032] In some embodiments, the plurality of battery cells are sequentially arranged along a second direction, and the second direction intersects with the first direction.

[0033] In the above technical solution, multiple battery cells are arranged in sequence along the second direction. When a battery cell has thermal runaway, the pressure relief hole erupts in the first direction, which has little impact on other battery cells arranged in sequence along the second direction, thereby improving the reliability of the battery.

[0034] In a third aspect, an embodiment of the present application further provides a battery, comprising the above-mentioned battery module.

[0035] In a fourth aspect, an embodiment of the present application further provides an electrical device, comprising the above-mentioned battery, and the battery is used to provide electrical energy. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments of the present application will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on the drawings without paying creative work.

[0037] Figure 1A schematic diagram of the structure of a vehicle provided in some embodiments of the present application;

[0038] Figure 2 A schematic diagram of the structure of a battery provided in some embodiments of the present application;

[0039] Figure 3 A schematic diagram of the structure of a battery module provided in some embodiments of the present application;

[0040] Figure 4 A schematic diagram of the structure of a battery unit provided in some embodiments of the present application;

[0041] Figure 5 A schematic diagram of the structure of a battery unit housing provided in some embodiments of the present application;

[0042] Figure 6 A schematic diagram of the structure of a top cover of a battery unit and a soft-pack battery cell provided in some embodiments of the present application;

[0043] Figure 7 Another structural schematic diagram of a top cover of a battery unit provided in some embodiments of the present application;

[0044] Figure 8 for Figure 4 A schematic diagram of the structure of the top cover in the battery unit shown;

[0045] Fig. 9 for Figure 6 Schematic diagram of the structure of the top cover shown.

[0046] The reference numerals of the specific embodiments are as follows:

[0047] 1. Vehicle; 2. Battery; 3. Controller; 4. Motor; 5. Battery module; 6. Box; 61. First part; 62. Second part; 7. Battery unit;

[0048] 71, housing; 711, accommodating chamber; 712, housing body; 713, bottom cover; 714, first end; 715, second end;

[0049] 72, soft pack battery cell; 721, first battery cell; 722, second battery cell; 723, first positive terminal; 724, first negative terminal; 725, second positive terminal; 726, second negative terminal;

[0050] 73, top cover; 731, main body; 732, pressure relief hole; 733, weak structure; 734, step structure; 7341, first step surface; 7342, second step surface; 7343, third step surface; 735, busbar; 736, first output electrode; 737, second output electrode; 738, insulating component;

[0051] 74. Fasteners;

[0052] X, first direction; Y, second direction; Z, third direction. DETAILED DESCRIPTION

[0053] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0054] Unless otherwise defined, all technical and scientific terms used in this application have the same meanings as those commonly understood by technicians in the technical field of this application; the terms used in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" in the specification and claims of this application and the above-mentioned drawings and any variations thereof are intended to cover non-exclusive inclusions. The terms "first", "second", etc. in the specification and claims of this application or the above-mentioned drawings are used to distinguish different objects, rather than to describe a specific order or a primary and secondary relationship.

[0055] Reference to "embodiment" in this application means that a particular feature, structure, or characteristic described in conjunction with the embodiment may be included in at least one embodiment of the present application. The appearance of the phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments.

[0056] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", and "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 a direct connection, or an indirect connection through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0057] The term "and / or" in this application is only a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this application generally indicates that the associated objects before and after are in an "or" relationship.

[0058] In the embodiments of the present application, the same reference numerals represent 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 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.

[0059] The term "plurality" used in the present application refers to two or more (including two).

[0060] 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 or a magnesium-ion battery cell, etc., and the embodiments of the present application do not limit this. The battery cell may be cylindrical, flat, rectangular or other shapes, etc., and the embodiments of the present application do not limit this.

[0061] The battery mentioned in the embodiments of the present application refers to a single physical module including one or more battery cells to provide higher voltage and capacity. For example, the battery mentioned in the present application may include a battery module or a battery pack. The battery generally includes a box for encapsulating one or more battery cells. The box can prevent liquid or other foreign matter from affecting the charging or discharging of the battery cells.

[0062] A battery cell includes an electrode assembly and an electrolyte. The electrode assembly includes a positive electrode sheet, a negative electrode sheet and a separator. A battery cell mainly relies on the movement of metal ions between the positive electrode sheet and the negative electrode sheet to work. The positive electrode sheet includes a positive current collector and a positive active material layer. The positive active material layer is coated on the surface of the positive current collector. The positive current collector includes a positive coating area and a positive electrode ear connected to the positive coating area. The positive coating area is coated with a positive active material layer, and the positive electrode ear is not coated with a positive active material layer. Taking a lithium-ion battery cell as an example, the material of the positive current collector can be aluminum, and the positive active material layer includes a positive active material. The positive active material can be lithium cobalt oxide, lithium iron phosphate, ternary lithium or lithium manganese oxide, etc. The negative electrode sheet includes a negative electrode current collector and a negative electrode active material layer, and the negative electrode active material layer is coated on the surface of the negative electrode current collector; the negative electrode current collector includes a negative electrode coating area and a negative electrode tab connected to the negative electrode coating area, and the negative electrode coating area is coated with a negative electrode active material layer, and the negative electrode tab is not coated with a negative electrode active material layer. The material of the negative electrode current collector can be copper, and the negative electrode active material layer includes a negative electrode active material, and the negative electrode active material can be carbon or silicon, etc. The material of the separator can be PP (polypropylene, polypropylene) or PE (polyethylene, polyethylene), etc.

[0063] A soft-pack battery module usually includes a plurality of electrically connected soft-pack battery cells, and each soft-pack battery cell usually uses a rectangular bracket to fix a certain number of soft-pack battery cells, such as fixing two soft-pack battery cells. The rectangular bracket is only arranged around the package of the soft-pack battery cell. When a soft-pack battery cell has thermal runaway, high-temperature gas will be ejected from the package in a disorderly manner, which is very likely to affect other soft-pack battery cells of the battery module, thereby causing a more serious thermal runaway of the battery and causing an explosion.

[0064] In view of this, the present application provides a battery cell, which includes a shell and a top cover, and a pressure relief hole is arranged on the top cover. In this way, when the soft-pack battery cell in the shell undergoes thermal runaway, the high-temperature gas will be ejected from the pressure relief hole of the top cover in a direction instead of in a disorderly manner, thereby reducing the impact on the soft-pack battery cells in other battery cells, improving the reliability of the battery, and reducing the risk of explosion.

[0065] The battery unit described in the embodiments of the present application is suitable for a battery module, a battery, and an electrical device using the battery.

[0066] The electrical device may be a vehicle, a mobile phone, a portable device, a laptop computer, a ship, a spacecraft, an electric toy, an electric tool, and the like. The vehicle may be a fuel vehicle, a gas vehicle, or a new energy vehicle, and the new energy vehicle may be a pure electric vehicle, a hybrid vehicle, or an extended-range vehicle, and the like; the spacecraft may include an airplane, a rocket, a space shuttle, and a spacecraft, and the like; the electric toy may include a fixed or mobile electric toy, such as a game console, an electric car toy, an electric ship toy, and an electric airplane toy, and the like; the electric tool may include a metal cutting electric tool, a grinding electric tool, an assembly electric tool, and an electric tool for railways, such as an electric drill, an electric grinder, an electric wrench, an electric screwdriver, an electric hammer, an impact drill, a concrete vibrator, and an electric planer, and the like. The embodiments of the present application do not impose any special restrictions on the above-mentioned electrical devices.

[0067] For the convenience of description, the following embodiments are described by taking the electric device as a vehicle as an example.

[0068] Figure 1 A schematic diagram of the structure of a vehicle provided for some embodiments of the present application.

[0069] like Figure 1 As shown, a battery 2 is disposed inside the vehicle 1, and the battery 2 may be disposed at the bottom, head, or tail of the vehicle 1. The battery 2 may be used to power the vehicle 1, for example, the battery 2 may be used as an operating power source for the vehicle 1.

[0070] The vehicle 1 may further include a controller 3 and a motor 4 , wherein the controller 3 is used to control the battery 2 to supply power to the motor 4 , for example, to meet the power requirements of starting, navigating, and driving the vehicle 1 .

[0071] In some embodiments of the present application, the battery 2 can not only serve as an operating power source for the vehicle 1, but also serve as a driving power source for the vehicle 1, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1.

[0072] Figure 2 A schematic diagram of the structure of a battery provided in some embodiments of the present application;

[0073] like Figure 2 As shown, the battery 2 includes a box body 6 and at least one battery module 5. The box body 6 has a receiving space, and the battery module 5 is arranged in the receiving space.

[0074] In the battery 2, there can be one or more battery modules 5. If there are multiple battery modules 5, the multiple battery modules 5 can be connected in series, in parallel, or in mixed connection. Mixed connection means that the multiple battery modules 5 are connected in series and in parallel.

[0075] Exemplarily, the box body 6 may include a first part 61 and a second part 62, the first part 61 and the second part 62 cover each other, and the first part 61 and the second part 62 jointly define a storage space for accommodating the battery module 5. The second part 62 may be a hollow structure with one end open, and the first part 61 may be a plate-like structure, and the first part 61 covers the open side of the second part 62, so that the first part 61 and the second part 62 jointly define a storage space; the first part 61 and the second part 62 may also be hollow structures with one side open, and the open side of the first part 61 covers the open side of the second part 62. Of course, the box body 6 formed by the first part 61 and the second part 62 may be in various shapes, such as a cylinder, a cuboid, etc.

[0076] Figure 3 A schematic diagram of the structure of a battery module provided in some embodiments of the present application.

[0077] like Figure 3 As shown, the present application provides a battery module 5 including a plurality of battery cells 7 .

[0078] The multiple battery cells 7 in the embodiment of the present application can be connected in series, in parallel, or in mixed connection. Mixed connection means that the multiple battery cells 7 are connected in series and in parallel.

[0079] The multiple battery cells 7 in the embodiment of the present application are arranged in rows. Exemplarily, the battery module 5 includes a row of battery cells 7 .

[0080] The battery module 5 of the embodiment of the present application further includes a plurality of tabs, which are used to electrically connect the output electrodes of two adjacent battery cells 7 .

[0081] Figure 4 A schematic diagram of the structure of a battery unit provided in some embodiments of the present application; Figure 5A schematic diagram of the structure of a battery unit housing provided in some embodiments of the present application; Figure 6 A schematic diagram of the structure of a top cover of a battery unit and a soft-pack battery cell provided in some embodiments of the present application; Figure 7 Another schematic diagram of the structure of the top cover of the battery cell provided in some embodiments of the present application.

[0082] See also Figure 4-Figure 7 The present application provides a battery cell 7, which is used in a battery module 5. The battery module 5 includes multiple battery cells 7, and the battery cell 7 includes a shell 71, multiple soft-pack battery cells 72 and a top cover 73. The shell 71 has a accommodating cavity 711, and the shell 71 is also provided with an opening connected to the accommodating cavity; the multiple soft-pack battery cells 72 are located in the accommodating cavity 711; the top cover 73 includes a main body 731, the main body 731 covers the opening of the shell 71, and has a pressure relief hole 732 that penetrates itself along a first direction X, and the first direction X is parallel to the arrangement direction of the soft-pack battery cells 72 to the top cover 73.

[0083] The battery unit 7 of the embodiment of the present application includes at least two soft-pack battery cells 72. Exemplarily, the battery unit 7 includes four soft-pack battery cells 72. Optionally, the number of soft-pack battery cells 72 is between 2 and 5. The multiple soft-pack battery cells 72 of the embodiment of the present application can be connected in series, in parallel, or in mixed connection. Mixed connection means that the multiple soft-pack battery cells 72 are both connected in series and in parallel.

[0084] The main body 731 and the shell 71 of the embodiment of the present application can be connected by welding, riveting, etc. Exemplarily, the shell 71 has only one opening, and the main body 731 covers the opening of the shell 71. Further, the top cover 73 covers the shell 71 to form a closed space.

[0085] The main body 731 of the embodiment of the present application may be a plate-like structure, or a hollow structure with one side open, and the open side of the main body 731 covers the open side of the shell 71 .

[0086] The housing 71 of the embodiment of the present application can be an integrally formed component, directly forming the accommodating cavity 711, without the need for a connection assembly process. Exemplarily, the housing 71 includes a side portion and a bottom portion, the bottom portion is arranged opposite to the top cover 73, and the side portion is arranged around the whole formed by multiple soft-pack battery cells 72. Of course, the side portion and the bottom portion of the housing 71 can also be two separate components, which are connected by a connection process to form the housing 71.

[0087] The number of the pressure relief hole 732 in the embodiment of the present application may be one or more, and the shape of the pressure relief hole 732 may be rectangular, circular or irregular.

[0088] The first direction X in the embodiment of the present application is parallel to the arrangement direction of the soft-pack battery cells 72 to the top cover 73 , and can be regarded as the thickness direction of the top cover 73 .

[0089] The battery module 5 is split into a plurality of battery cells 7, and the battery cells 7 are configured to include a shell 71 and a top cover 73, and a pressure relief hole 732 is provided on the top cover 73. In this way, when the soft-pack battery cell 72 in the shell 71 undergoes thermal runaway, the high-temperature gas will be directedly ejected from the pressure relief hole 732 of the top cover 73, and will not be ejected in a disorderly manner, thereby reducing the impact on the soft-pack battery cells 72 in other battery cells 7 and improving the reliability of the battery 2. Moreover, by reasonably setting the first direction X in the battery module 5, the high-temperature gas can further reduce the impact on the soft-pack battery cells 72 of other battery cells 7, and further improve the reliability of the battery 2. In addition, since the shell 71 and the top cover 73 form a relatively closed space, they form a protective effect on themselves, further reducing the risk of thermal runaway in other battery cells 7.

[0090] In some embodiments, there are multiple pressure relief holes 732 , and the multiple pressure relief holes 732 are arranged at intervals.

[0091] The shapes of the multiple pressure relief holes 732 in the embodiment of the present application may all be the same, or only a part of the pressure relief holes 732 may have the same shape, or the shapes of the multiple pressure relief holes 732 may be different.

[0092] The multiple pressure relief holes 732 of the embodiment of the present application may be arranged in an array or in a random arrangement.

[0093] Providing a plurality of pressure relief holes 732 arranged at intervals can improve the structural strength of the locations where the pressure relief holes 732 are located, thereby improving the reliability of the battery unit 7 in use.

[0094] Figure 8 for Figure 4 Schematic diagram of the structure of the top cover in the battery unit shown.

[0095] See also Figure 8 In some embodiments, the top cover 73 further includes a weak structure 733, which is connected to the side of the main body 731 away from the accommodating cavity 711 and covers the pressure relief hole 732, and the weak structure 733 is configured to be opened by high-temperature gas when thermal runaway occurs in the soft-pack battery cell 72.

[0096] The weak structure 733 of the embodiment of the present application can be a metal sheet; it can also be a plastic part, such as PP, PET, PC and other common plastic materials, and its thickness can be selected to be 0.3mm-1mm. The thickness of the weak structure 733 of the embodiment of the present application can be determined according to the material of the weak structure 733 combined with the type and safety requirements of the soft-pack battery cell 72.

[0097] The weak structure 733 of the embodiment of the present application can be connected to the main body 731 by bonding or welding.

[0098] Exemplarily, the weak structure 733 completely covers the pressure relief hole 732 .

[0099] A weak structure 733 is provided. Under normal operating temperature, the weak structure 733 covers the pressure relief hole 732, providing a relatively stable working environment for the soft-pack battery cell 72 and reducing dust, particles, etc. from entering the accommodating cavity 711. When thermal runaway occurs, high-temperature gas can break through the weak structure 733 to relieve pressure.

[0100] In some embodiments, the weak structure 733 is an insulating member.

[0101] Exemplarily, the weak structure 733 is mica paper.

[0102] By configuring the weak structure 733 as an insulating part, the risk of short circuiting other battery cells 7 when being blown open by high-temperature gas is reduced, thereby improving the reliability of the battery cells 7.

[0103] Please continue reading Figure 4 In some embodiments, the end of the shell 71 surrounds the outer peripheral side of the main body 731, and the battery cell 7 also includes a fastener 74, which is arranged around one end of the shell 71 close to the main body 731 and fixes the shell 71 to the main body 731.

[0104] The fastener 74 of the embodiment of the present application can be a steel strip or a plastic material, such as PET. The fastener 74 of the embodiment of the present application uses tension to fix the shell 71 to the main body 731 , and continuously surrounds the shell 71 .

[0105] Exemplarily, when the fastener 74 is a steel belt, during assembly, the strip steel belt is firstly wrapped around the outer circumference of the main body 731 , and then the two ends of the strip steel belt are welded to form an annular steel belt to fix the shell 71 to the main body 731 .

[0106] Exemplarily, when the fastener 74 is a plastic belt, during assembly, the strip plastic belt is first wrapped around the outer circumference of the main body 731, and then the two ends of the strip plastic belt are fused and connected at high temperature to form an annular plastic belt to fix the shell 71 to the main body 731.

[0107] The connection is carried out using the fastener 74, which is convenient to operate and has high production efficiency.

[0108] Fig. 9 for Figure 6 Schematic diagram of the structure of the top cover shown.

[0109] See also Fig. 9In some embodiments, a step structure 734 is formed on at least part of the outer peripheral side of the main body 731, and the step structure 734 includes a first step surface 7341, a second step surface 7342, and a third step surface 7343 connected in sequence, the second step surface 7342 intersects with the first direction X, the first step surface 7341 is located on the side of the third step surface 7343 close to the soft-pack battery cell 72, the shell 71 abuts against the first step surface 7341, and the shell 71 and the fastener 74 are limited to the second step surface 7342.

[0110] The first step surface 7341 , the second step surface 7342 and the third step surface 7343 of the embodiment of the present application are arranged in sequence in the walking extension direction of the step structure 734 .

[0111] The plane where the first step surface 7341 of the embodiment of the application is located and the plane where the second step surface 7342 is located can form an acute angle, an obtuse angle or a right angle, and the plane where the second step surface 7342 is located and the plane where the third step surface 7343 is located can form an acute angle, an obtuse angle or a right angle.

[0112] Optionally, the first step surface 7341 and the second step surface 7342 form a right angle, and the second step surface 7342 and the third step surface 7343 form a right angle.

[0113] Optionally, the second step surface 7342 is perpendicular to the first direction X.

[0114] Optionally, the entire outer circumference of the main body 731 is formed with a step structure 734 .

[0115] The shell 71 and the fastener 74 of the embodiment of the present application are limited to the second step surface 7342, and the shell 71 or the fastener 74 and the second step surface 7342 may be against each other or there may be a gap.

[0116] A step structure 734 is formed on at least part of the outer peripheral side of the main body 731, so that the second step surface 7342 can form a limiting effect on the fastener 74, reducing the risk of the fastener 74 falling off the shell 71, and at the same time, it is also convenient to position the shell 71 and facilitate assembly.

[0117] Please continue reading Figure 5In some embodiments, the shell 71 includes a shell body 712 and a bottom cover 713, and the shell body 712 has a first state before molding and a second state after molding. In the first state, the shell body 712 includes a first end 714 and a second end 715 opposite to each other in the surrounding direction, and the first end 714 and the second end 715 can be separated from each other to form an opening for the soft-pack battery cell 72 to enter the shell body 712; in the second state, the shell body 712 surrounds the soft-pack battery cell 72, the first end 714 and the second end 715 are connected, the top cover 73 covers one end of the shell body 712 in the first direction X, and the bottom cover 713 covers the other end of the shell body 712 in the first direction X.

[0118] The first end 714 and the second end 715 of the embodiment of the present application can form an opening into the shell body 712 in the first state. The two can be spaced apart or offset when no force is applied. The shell body 712 of the embodiment of the present application deforms after being subjected to force, so that the distance between the first end 714 and the second end 715 gradually increases, forming a suitable opening for the soft-pack battery cell 72 to enter. Of course, the distance between the first end 714 and the second end 715 decreases after the force is removed.

[0119] In the second state, the circumferential direction of the shell body 712 is perpendicular to the first direction X.

[0120] In the second state, the first end 714 and the second end 715 may be connected by welding or bonding.

[0121] For example, the shell body 712 and the top cover 73 may be connected by bundling or welding. The shell body 712 and the bottom cover 713 may be connected by welding or bonding.

[0122] Optionally, the cross section of the shell body 712 in the first direction X is rectangular, and the first end 714 and the second end 715 are located on a side of the shell body 712 with a smaller area.

[0123] The shell body 712 of the embodiment of the present application may be formed by connecting several parts, or may be an integrally formed structure.

[0124] The bottom cover 713 of the embodiment of the present application may be a metal member or an insulating member.

[0125] The shell 71 is configured to include a shell body 712 and a bottom cover 713, and the shell body 712 can form an opening in the first state. In this way, when the soft-pack battery cell 72 is assembled into the shell 71, the opening is opened to a suitable size, and the soft-pack battery cell 72 is placed into the shell body 712, which is convenient to operate and has a high assembly efficiency. In addition, compared with the solution of putting the soft-pack battery cell 72 into the shell 71 from one end of the first direction X, the interference between the soft-pack battery cell 72 and the edge of the non-deformable shell 71 can be reduced, the possibility of damage to the soft-pack battery cell 72 is reduced, and the yield rate is improved.

[0126] In some embodiments, the shell body 712 is an integrally formed piece.

[0127] The shell body 712 is configured as an integrally formed part, which can reduce the connection process and improve production efficiency. In addition, when the shell body 712 is subjected to force to form an opening, the integrally formed shell body 712 can have good toughness and strength, reducing the possibility of damage due to force.

[0128] In some embodiments, the bottom cover 713 is an insulating member.

[0129] The bottom cover 713 of the embodiment of the present application may be made of plastic or mica paper.

[0130] Optionally, the bottom cover 713 is bonded to the shell body 712 .

[0131] The bottom cover 713 of the embodiment of the present application may be a plate-shaped member, or a hollow structure with one end open, and the open side of the bottom cover 713 is covered with the shell body 712 .

[0132] The bottom cover 713 is set as an insulating member, which can reduce material costs and can be connected by convenient connection methods such as bonding.

[0133] See also Figure 6-Figure 9 In some embodiments, the plurality of soft-pack battery cells 72 include a first battery cell 721 and a second battery cell 722 arranged along a second direction Y, the first battery cell 721 includes a first positive terminal 723 and a first negative terminal 724 arranged along a third direction Z, the second battery cell 722 includes a second positive terminal 725 and a second negative terminal 726 arranged along the third direction Z, the top cover 73 also includes a busbar 735, the busbar 735 is disposed on a side of the body 731 facing the accommodating cavity 711, the first positive terminal 723 and the second negative terminal 726 are respectively attached and connected to opposite sides of the busbar 735 along the second direction Y and are electrically connected through the busbar 735, and the second direction Y, the third direction Z and the first direction X intersect each other.

[0134] The busbar 735 of the embodiment of the present application may be U-shaped, plate-shaped, or in other shapes.

[0135] The busbar 735 of the embodiment of the present application may be threadedly connected or riveted to the main body 731 .

[0136] The first positive terminal 723 and the second negative terminal 726 of the embodiment of the present application are respectively attached to the opposite sides of the busbar 735 along the second direction Y, and can be conductively connected by welding or conductive adhesive bonding. The first positive terminal 723 and the second negative terminal 726 of the embodiment of the present application are not bent and are directly attached to the busbar 735.

[0137] Optionally, the second direction Y and the third direction Z are perpendicular to the first direction X in pairs.

[0138] Exemplarily, when the number of soft-pack battery cells 72 is four, the number of busbars 735 is two, two soft-pack battery cells 72 are electrically connected through one busbar 735, and the other two soft-pack battery cells 72 are electrically connected through the other busbar 735. Optionally, the two busbars 735 are spaced apart along the second direction Y.

[0139] A busbar 735 is provided, and the first positive terminal 723 and the second negative terminal 726 are directly attached to the busbar 735. In this way, the first positive terminal 723 and the second negative terminal 726 do not need to be bent or welded to achieve electrical connection, that is, the electrical connection between the soft-pack battery cells 72 is achieved in a relatively straight state, thereby improving the problem of bending causing the ear glue of the soft-pack battery cell 72 to be damaged and then causing the soft-pack battery cell 72 to leak, and reducing the defective rate of the battery unit 7.

[0140] In some embodiments, the top cover 73 also includes a first output electrode 736 and a second output electrode 737 arranged along the second direction Y. The first output electrode 736 and the second output electrode 737 are embedded in the main body 731 at intervals and extend from a side of the main body 731 facing the accommodating cavity 711 to a side of the main body 731 away from the accommodating cavity 711. A portion of the first output electrode 736 close to the accommodating cavity 711 is conductively connected to the first negative terminal 724, and a portion of the second output electrode 737 close to the accommodating cavity 711 is conductively connected to the second positive terminal 725.

[0141] When the top cover 73 is made of metal, the first output electrode 736 and the second output electrode 737 are respectively insulated from the top cover 73 .

[0142] The first output electrode 736 of the embodiment of the present application can be electrically connected to the first negative terminal 724 by welding or bonding, and the second output electrode 737 can be electrically connected to the second positive terminal 725 by welding or bonding, and the first negative terminal 724 can be electrically connected to the first output electrode 736 by welding or bonding, and the second positive terminal 725 can be electrically connected to the second output electrode 737 by welding or bonding, and the second positive terminal 725 can be electrically connected to the first negative terminal 724 by welding or bonding, and the second output electrode 736 can be electrically connected to the first negative terminal 724 by welding or bonding, and the second output electrode 737 can be electrically connected to the first negative terminal 724 by welding or bonding, and the second output electrode 736 can be electrically connected to the first negative terminal 724 by welding or bonding, and the second output electrode 736 can be electrically connected to the first negative terminal 724 by welding or bonding, and the second output electrode 736 can be electrically connected to the first negative terminal 724 by welding or bonding, and the second output electrode 736 can be electrically connected to the first negative terminal 725 by welding or bonding, and the second output electrode 736 can be electrically connected to the first negative terminal 724 by welding or bonding, and the second output electrode 737 can be electrically connected to the first positive ...7 can be electrically connected to the first negative terminal 725 by welding or bonding, and the second output electrode 736 can be electrically connected to the first negative terminal

[0143] When the number of soft-pack battery cells 72 is four, the top cover 73 includes two pairs of output electrodes, each pair of output electrodes includes a first output electrode 736 and a second output electrode 737, and a pair of output electrodes connects two soft-pack battery cells 72. Optionally, the two pairs of output electrodes are arranged at intervals along the second direction Y. When forming the battery module 5, one pair of first output electrodes 736 and another pair of second output electrodes 737 are arranged adjacent to each other and electrically connected by a bar sheet, and the remaining second output electrode 737 and the first output electrode 736 are electrically connected to other battery cells 7 by a bar sheet.

[0144] The first output electrode 736 and the second output electrode 737 are disposed through the main body 731 , which can save the need for setting up adapter components and facilitate the connection with the first negative terminal 724 and the second positive terminal 725 .

[0145] In some embodiments, the body portion 731 is an insulating member.

[0146] Optionally, the main body 731 may be made of plastic or plastic material.

[0147] Setting the main body 731 as an insulating member can reduce the risk of short circuit between the first output electrode 736, the second output electrode 737, the bus 735 and the top cover 73, improve the reliability of the battery cell 7, and also omit the insulation process between the first output electrode 736, the second output electrode 737, the bus 735 and the top cover 73.

[0148] In some embodiments, the top cover 73 also includes an insulating component 738, which is disposed on a side of the main body 731 facing the accommodating cavity 711, and the first output electrode 736 and the second output electrode 737 are respectively disposed on opposite sides of the insulating component 738 along the second direction Y. The insulating component 738 extends toward the accommodating cavity 711 and electrically isolates the first negative terminal 724 and the second positive terminal 725.

[0149] The insulating component 738 of the embodiment of the present application can be made of plastic or other materials.

[0150] The insulating component 738 of the embodiment of the present application can be a plate-shaped member, which has two side surfaces opposite to each other along the second direction Y, and the first output electrode 736 and the second output electrode 737 are respectively attached to the two side surfaces; it can also be formed by two parts with a thick upper part and a thin lower part, and the first output electrode 736 and the second output electrode 737 are attached to the two side surfaces of the upper part.

[0151] The insulating component 738 is provided to insulate the first negative terminal 724 and the second positive terminal 725 , thereby reducing the probability of contact between the two, reducing the risk of short circuit, and improving the reliability of the battery unit 7 .

[0152] The embodiment of the present application further provides a battery module 5, comprising the above-mentioned battery unit 7.

[0153] In some embodiments, the plurality of battery cells 7 are sequentially arranged along a second direction Y, and the second direction Y intersects with the first direction X.

[0154] Optionally, the first direction X is perpendicular to the second direction Y.

[0155] The plurality of battery cells 7 are sequentially arranged along the second direction Y. When the battery cell 7 has thermal runaway, the pressure relief hole 732 is ejected along the first direction X, which has little impact on other battery cells 7 sequentially arranged along the second direction Y, thereby improving the reliability of the battery 2.

[0156] The present application also provides a battery 2, comprising the above-mentioned battery module 5,

[0157] The embodiment of the present application further provides an electrical device, comprising the above-mentioned battery 2, and the battery 2 is used to provide electrical energy.

[0158] See also Figure 3-Figure 8The embodiment of the present application provides a battery cell 7, which is used in a battery module 5. The battery module 5 includes a plurality of battery cells 7, and the battery cell 7 includes a shell 71, a plurality of soft-pack battery cells 72 and a top cover 73. The shell 71 has a receiving cavity 711, and the shell 71 is also provided with an opening connected to the receiving cavity 711; the plurality of soft-pack battery cells 72 are located in the receiving cavity 711; the top cover 73 includes a body 731, the body 731 covers the opening of the shell 71 and has a pressure relief hole 732 that penetrates itself along a first direction X, and the first direction X is parallel to the arrangement direction of the soft-pack battery cells 72 to the top cover 73. There are a plurality of pressure relief holes 732, and the plurality of pressure relief holes 732 are arranged at intervals. The top cover 73 also includes a weak structure 733, which is connected to the side of the body 731 away from the receiving cavity 711 and covers the pressure relief hole 732, and the weak structure 733 is configured to be opened by high-temperature gas when the soft-pack battery cells 72 have thermal runaway. The weak structure 733 is an insulating member. The end of the shell 71 surrounds the outer peripheral side of the main body 731. The battery unit 7 also includes a fastener 74, which is arranged around one end of the shell 71 close to the main body 731 and fixes the shell 71 to the main body 731. A step structure 734 is formed on at least part of the outer peripheral side of the main body 731. The step structure 734 includes a first step surface 7341, a second step surface 7342 and a third step surface 7343 connected in sequence. The second step surface 7342 intersects with the first direction X. The first step surface 7341 is located on the side of the third step surface 7343 close to the soft-pack battery cell 72. The shell 71 abuts against the first step surface 7341, and the shell 71 and the fastener 74 are limited to the second step surface 7342. The shell 71 includes a shell body 712 and a bottom cover 713. The shell body 712 has a first state before molding and a second state after molding. In the first state, the shell body 712 includes a first end 714 and a second end 715 opposite to each other in the circumferential direction. The first end 714 and the second end 715 can be separated from each other to form an opening for the soft-pack battery cell 72 to enter the shell body 712. In the second state, the shell body 712 surrounds the soft-pack battery cell 72, the first end 714 and the second end 715 are connected, the top cover 73 covers one end of the shell body 712 in the first direction X, and the bottom cover 713 covers the other end of the shell body 712 in the first direction X. The shell body 712 is an integrally molded part. The bottom cover 713 is an insulating part.

[0159] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application may be combined with each other.

[0160] 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 it. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein, but these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A battery cell, the battery cell being used in a battery module, the battery module comprising a plurality of electrically connected battery cells, characterized in that: The battery unit comprises: A shell having a receiving cavity, wherein the shell is further provided with an opening communicating with the receiving cavity; A plurality of soft-pack battery cells are located in the accommodation cavity; The top cover comprises a main body, which covers the opening of the shell and has a pressure relief hole penetrating the main body along a first direction, wherein the first direction is parallel to the arrangement direction of the soft-pack battery cells to the top cover.

2. The battery cell according to claim 1, characterized in that: There are multiple pressure relief holes, and the multiple pressure relief holes are arranged at intervals.

3. The battery cell according to claim 1, characterized in that The top cover also includes a weak structure, which is connected to a side of the main body away from the accommodating cavity and covers the pressure relief hole, and the weak structure is configured to be opened by high-temperature gas when thermal runaway occurs in the soft-pack battery cell.

4. The battery cell according to claim 3, characterized in that: The weak structure is an insulating member.

5. The battery cell according to claim 1, characterized in that: The end of the shell surrounds the outer peripheral side of the main body. The battery unit further includes a fastener, which is disposed around one end of the shell body close to the main body and fixes the shell body to the main body.

6. The battery cell according to claim 5, characterized in that: A step structure is formed on at least part of the outer circumference of the main body, and the step structure includes a first step surface, a second step surface and a third step surface connected in sequence, the second step surface intersects with the first direction, the first step surface is located on the side of the third step surface close to the soft-pack battery cell, the shell abuts against the first step surface, and the shell and the fastener are limited to the second step surface.

7. The battery cell according to any one of claims 1 to 6, characterized in that: The housing comprises a housing body and a bottom cover, wherein the housing body has a first state before molding and a second state after molding. In the first state, the shell body includes a first end and a second end opposite to each other in a surrounding direction, and the first end and the second end can be separated from each other to form an opening for the soft-pack battery cell to enter the shell body; in the second state, the shell body surrounds the soft-pack battery cell, the first end and the second end are connected, the top cover covers one end of the shell body in the first direction, and the bottom cover covers the other end of the shell body in the first direction.

8. The battery cell according to claim 7, characterized in that: The shell body is an integrally formed part.

9. The battery cell according to claim 7, characterized in that: The bottom cover is an insulating member.

10. The battery cell according to claim 1, characterized in that: The plurality of soft-pack battery cells include a first battery cell and a second battery cell arranged along a second direction, the first battery cell includes a first positive terminal and a first negative terminal arranged along a third direction, the second battery cell includes a second positive terminal and a second negative terminal arranged along the third direction, The top cover also includes a busbar, which is arranged on a side of the main body facing the accommodating cavity, the first positive terminal and the second negative terminal are respectively attached to opposite sides of the busbar along the second direction and are electrically connected through the busbar, and the second direction and the third direction intersect with the first direction in pairs.

11. The battery cell according to claim 10, characterized in that: The top cover also includes a first output electrode and a second output electrode arranged along the second direction, the first output electrode and the second output electrode are embedded in the main body at an interval, and extend from a side of the main body facing the accommodating cavity to a side of the main body away from the accommodating cavity, a portion of the first output electrode close to the accommodating cavity is conductively connected to the first negative terminal, and a portion of the second output electrode close to the accommodating cavity is conductively connected to the second positive terminal.

12. The battery cell according to claim 10, characterized in that The main body is an insulating member.

13. The battery cell according to claim 11, characterized in that The top cover also includes an insulating component, which is arranged on a side of the main body facing the accommodating cavity, and the first output electrode and the second output electrode are respectively arranged on opposite sides of the insulating component along the second direction. The insulating component extends toward the accommodating cavity and electrically isolates the first negative terminal and the second positive terminal.

14. A battery module, characterized in that: The invention comprises a plurality of battery cells according to any one of claims 1 to 13.

15. The battery module according to claim 14, characterized in that: The plurality of battery cells are arranged in sequence along a second direction, and the second direction intersects with the first direction.

16. A battery, characterized in that: Comprising the battery module as claimed in claim 14 or 15.

17. An electrical device, characterized in that: Comprising a battery as claimed in claim 16, the battery is used to provide electrical energy.

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