WO2023245842A1

WO2023245842A1 - Pressure relief mechanism, battery cell, battery and electric device

Info

Publication number: WO2023245842A1
Application number: PCT/CN2022/112990
Authority: WO
Inventors: 杨飘飘; 李耀; 陈小波; 顾明光; 钱欧
Original assignee: 宁德时代新能源科技股份有限公司
Priority date: 2022-06-21
Filing date: 2022-08-17
Publication date: 2023-12-28
Also published as: CN217468689U

Abstract

The present application relates to a pressure relief mechanism, a battery cell, a battery and an electric device. During designing, at least one of the parameters, i.e., a length L in a first direction and a width W in a second direction, is associated with the thickness δ of a pressure relief portion, and the ratio thereof is rationally controlled, such that the pressure relief mechanism maintains rational and effective dimension parameters. In this way, while controlling the pressure relief performance, the present application can effectively prevent the case where it is not possible for the pressure relief portion to rupture due to the pressure relief portion having an excessively large thickness and a pressure relief body having a very small length or width. In addition, the present application can also effectively avoid excessively high machining precision requirements and increased manufacturing difficulties caused by the pressure relief portion having an excessively small thickness and the pressure relief body having an excessively large length or width. Thus, the guidance on pressure relief mechanism manufacturing is improved.

Description

Pressure relief mechanism, battery cells, batteries and electrical devices

cross reference

This application cites Chinese patent application No. 202221557104.9 titled "Pressure Relief Mechanism, Battery Cell, Battery and Electrical Device" submitted on June 21, 2022, which is fully incorporated into this application by reference.

Technical field

This application relates to the field of battery technology, and in particular to a pressure relief mechanism, battery cells, batteries and electrical devices.

Background technique

Whether it is a battery cell or a power supply component such as a battery, a certain amount of air pressure will be generated inside after a period of operation. If the air pressure cannot be discharged in time, it will easily explode and pose a safety hazard. For this reason, a pressure relief mechanism is usually provided on the battery cell or battery to discharge the internal gas and reduce the air pressure. However, due to the structural design flaws of the existing pressure relief mechanism, it is difficult for the pressure relief mechanism to explode and effective pressure relief cannot be achieved; or, the processing accuracy is increased and the manufacturing difficulty is increased.

Contents of the invention

Based on this, it is necessary to provide a pressure relief mechanism, battery cells, batteries and electrical devices that can not only ensure effective explosion, but also reduce the difficulty of production and provide guidance for the production of pressure relief mechanisms.

In a first aspect, this application provides a pressure relief mechanism, including: a pressure relief body, the length of the pressure relief body along the first direction is marked as L, and the width of the pressure relief body along the second direction is marked as W; It has a pressure relief part, and the thickness of the pressure relief part along the thickness direction of the pressure relief body is recorded as δ, and the first direction, the second direction and the thickness direction of the pressure relief body intersect each other; where, 0.0001≤δ/L≤1; and/ Or, 0.0001≤δ/W≤1.

When designing the above-mentioned pressure relief mechanism, at least one parameter of the length L along the first direction and the width W along the second direction is associated with the thickness δ of the pressure relief portion, and the ratio between the two is reasonably controlled such that The pressure relief mechanism maintains reasonable and effective dimensional parameters. In this way, when controlling the pressure relief performance, it can effectively avoid that the thickness of the pressure relief part is too large, but the length or width of the pressure relief body is very small, making it difficult for the pressure relief part to explode; at the same time, it can also effectively avoid that the thickness of the pressure relief part is too small. , and the length or width of the pressure relief body is too large, which leads to high processing accuracy requirements and increases the difficulty of production. This provides guidance for the production of pressure relief mechanisms.

In some embodiments, 0.0001≤δ/L≤0.1. Such a design further optimizes the ratio of the thickness of the pressure relief part to the length of the pressure relief body, which can not only ensure that the pressure relief part is stably exploded, but also reduce the manufacturing difficulty and cost.

In some embodiments, 0.0001≤δ/W≤0.1. Such a design further optimizes the ratio of the thickness of the pressure relief part to the width of the pressure relief body, which can not only ensure that the pressure relief part is stably exploded, but also reduce the manufacturing difficulty and cost.

In some embodiments, the first direction and the second direction are arranged perpendicularly. In this way, the first direction and the second direction are designed to be vertical, which facilitates accurate acquisition of length and width data and improves the pressure relief performance of the pressure relief mechanism.

In a second aspect, the present application provides a battery cell, which includes: a casing with an accommodating cavity inside, and a pressure relief hole connected to the accommodating cavity; an electrode assembly accommodated in the accommodating cavity; as above For any pressure relief mechanism, the pressure relief body seals the pressure relief hole.

The above-mentioned battery cells use the above pressure relief mechanism to reasonably control the ratio between the two, so that the pressure relief mechanism maintains reasonable and effective size parameters. In this way, when controlling the pressure relief performance, it can effectively avoid that the thickness of the pressure relief part is too large, but the length or width of the pressure relief body is very small, making it difficult for the pressure relief part to explode; at the same time, it can also effectively avoid that the thickness of the pressure relief part is too small. , and the length or width of the pressure relief body is too large, which leads to high processing accuracy requirements and increases the difficulty of production. This provides guidance for the production of pressure relief mechanisms.

In a third aspect, the present application provides a battery, including: a box; battery cells such as the above are contained in the box; a support member is provided on the box and supports the battery cells, and is provided with a leakage connection The exhaust holes are arranged opposite to the pressure mechanism.

The above-mentioned battery uses the above pressure relief mechanism to reasonably control the ratio between the two, so that the pressure relief mechanism maintains reasonable and effective dimensional parameters. In this way, when controlling the pressure relief performance, it can effectively avoid that the thickness of the pressure relief part is too large, but the length or width of the pressure relief body is very small, making it difficult for the pressure relief part to explode; at the same time, it can also effectively avoid that the thickness of the pressure relief part is too small. , and the length or width of the pressure relief body is too large, which leads to high processing accuracy requirements and increases the difficulty of production. This provides guidance for the production of pressure relief mechanisms.

In some embodiments, the projected area of the pressure relief body in the plane formed by the first direction and the second direction is marked as S, and the opening area of the exhaust hole is marked as D; where, 0.005≤D/S≤10000. In this way, the ratio of the opening area D of the exhaust hole and the projected area S of the pressure relief body can be reasonably controlled to ensure smooth exhaust after pressure relief; at the same time, it can also ensure that the battery cells are stably supported and improve the overall structural mechanical properties of the battery. .

In some embodiments, 0.1≤D/S≤3000. In this way, further optimizing the ratio of the opening area D of the exhaust hole to the projected area S of the pressure relief body can not only ensure smooth exhaust, but also ensure sufficient support from the supporting members and improve the mechanical properties of the battery.

In some embodiments, the support component is a water-cooling component, and a water-cooling flow channel is provided in the water-cooling component. In this way, the support member is designed as a water-cooling member, which can not only support the battery cells, but also provide a water-cooling effect on the battery cells to ensure stable battery operation.

In some embodiments, the water-cooling component includes a first water-cooling component and a second water-cooling component. The first water-cooling component and the second water-cooling component are bonded together, and a water-cooling flow channel is formed between them. The battery cell is supported on the first water-cooling component. On the component, the pressure relief mechanism is provided on a side of the battery cell facing the first water-cooling component, and the exhaust hole penetrates the first water-cooling component and the second water-cooling component. In this way, the water-cooling component is designed into two parts: the first water-cooling part and the second water-cooling part, making the production of the water-cooling flow channel more convenient.

In some embodiments, the support member further includes an insulating layer, and the insulating layer closes the vent hole. In this way, the exhaust hole is sealed by the insulating layer to prevent liquid or air leakage from the exhaust hole.

In a fourth aspect, the present application provides an electrical device, including any of the above batteries, and the battery is used to provide electrical energy.

The above-mentioned electrical device adopts the above pressure relief mechanism and reasonably controls the ratio between the two, so that the pressure relief mechanism maintains reasonable and effective dimensional parameters. In this way, when controlling the pressure relief performance, it can effectively avoid that the thickness of the pressure relief part is too large, but the length or width of the pressure relief body is very small, making it difficult for the pressure relief part to explode; at the same time, it can also effectively avoid that the thickness of the pressure relief part is too small. , and the length or width of the pressure relief body is too large, which leads to high processing accuracy requirements and increases the difficulty of production. This provides guidance for the production of pressure relief mechanisms.

Description of the drawings

Various other advantages and benefits will become apparent to those of ordinary skill in the art upon reading the following detailed description of the preferred embodiments. The drawings are for the purpose of illustrating preferred embodiments only and are not to be construed as limiting the application. Also, the same parts are represented by the same reference numerals throughout the drawings. In the attached picture:

Figure 1 is a schematic structural diagram of a vehicle provided by some embodiments of the present application;

Figure 2 is an exploded schematic diagram of the structure of a battery provided by some embodiments of the present application;

Figure 3 is a schematic diagram of the exploded structure of a battery cell provided by some embodiments of the present application;

Figure 4 is a top view of a battery provided by some embodiments of the present application;

Figure 5 is a cross-sectional view of the battery in Figure 4 along the A-A direction;

Figure 6 is an enlarged schematic diagram of the structure at circle B in Figure 5.

10000, vehicle; 1000, battery; 2000, controller; 3000, motor; 100, battery cell; 10, pressure relief mechanism; 11, pressure relief body; 12, pressure relief part; 20, casing; 21, accommodation cavity ; 22. Opening; 23. Pressure relief hole; 30. Adapter; 40. Electrode assembly; 50. End cover; 200. Box; 300. Cover; 400. Supporting member; 410. Water cooling member; 411. Chapter One water-cooling component; 412, the second water-cooling component; 413, water-cooling flow channel; 414, exhaust hole; 415, insulation layer.

Detailed ways

The embodiments of the technical solution of the present application will be described in detail below with reference to the accompanying drawings. The following examples are only used to illustrate the technical solution of the present application more clearly, and are therefore only used as examples and cannot be used to limit the protection scope of the present application.

Unless otherwise defined, all technical and scientific terms used herein have the same meanings as commonly understood by those skilled in the technical field belonging to this application; the terms used herein are for the purpose of describing specific embodiments only and are not intended to be used in Limitation of this application; the terms "including" and "having" and any variations thereof in the description and claims of this application and the above description of the drawings are intended to cover non-exclusive inclusion.

In the description of the embodiments of this application, the technical terms "first", "second", etc. are only used to distinguish different objects, and cannot be understood as indicating or implying the relative importance or implicitly indicating the quantity or specificity of the indicated technical features. Sequence or priority relationship. In the description of the embodiments of this application, "plurality" means two or more, unless otherwise explicitly and specifically limited.

Reference herein to "an embodiment" means that a particular feature, structure or characteristic described in connection with the embodiment can be included in at least one embodiment of the present application. The appearances of this phrase in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. Those skilled in the art understand, both explicitly and implicitly, that the embodiments described herein may be combined with other embodiments.

In the description of the embodiments of this application, the term "and/or" is only an association relationship describing associated objects, indicating that there can be three relationships, such as A and/or B, which can mean: A exists alone, and A exists simultaneously and B, there are three cases of B alone. In addition, the character "/" in this article generally indicates that the related objects are an "or" relationship.

In the description of the embodiments of this application, the term "multiple" refers to more than two (including two). Similarly, "multiple groups" refers to two or more groups (including two groups), and "multiple pieces" refers to It is more than two pieces (including two pieces).

In the description of the embodiments of this application, the technical terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "back", "left", "right" and "vertical" The orientation or positional relationships indicated by "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. are based on those shown in the accompanying drawings. The orientation or positional relationship is only for the convenience of describing the embodiments of the present application and simplifying the description. It does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the implementation of the present application. Example limitations.

In the description of the embodiments of this application, unless otherwise clearly stated and limited, technical terms such as "installation", "connection", "connection" and "fixing" should be understood in a broad sense. For example, it can be a fixed connection or a removable connection. It can be disassembled and connected, or integrated; it can also be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be an internal connection between two elements or an interaction between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the embodiments of this application can be understood according to specific circumstances.

At present, judging from the development of the market situation, the application of power batteries is becoming more and more extensive. Power batteries are not only used in energy storage power systems such as hydropower, thermal power, wind power and solar power stations, but are also widely used in electric vehicles such as electric bicycles, electric motorcycles and electric cars, as well as in many fields such as military equipment and aerospace. . As the application fields of power batteries continue to expand, their market demand is also constantly expanding.

The applicant has noticed that during the structural design of the pressure relief mechanism, if the size relationship design is unreasonable, it will directly affect the pressure relief performance, as well as the difficulty and cost of manufacturing the pressure relief mechanism. For example: if the pressure relief mechanism is designed to be too thick, it will be difficult for the pressure relief part to explode, and effective pressure relief cannot be achieved; if the pressure relief mechanism is designed to be too thin, higher processing accuracy is required. In actual production, the thickness control accuracy tends to deteriorate. If the length of the pressure relief mechanism is too long, this trend will be aggravated.

Based on this, in order to solve the problems of poor pressure relief performance, difficulty in manufacturing or high cost caused by the design of the pressure relief mechanism, the applicant has designed a pressure relief mechanism after in-depth research. The length L along the first direction is At least one parameter of the width W along the second direction is related to the thickness δ of the pressure relief portion, and the ratio between them is controlled to be: 0.0001≤δ/L≤1; and/or, 0.0001≤δ/W≤1 .

During design, at least one parameter of the length L along the first direction and the width W along the second direction is associated with the thickness δ of the pressure relief portion, and the ratio between the two is reasonably controlled so that the pressure relief mechanism remains reasonable and Valid size parameters. In this way, when controlling the pressure relief performance, it can effectively avoid that the thickness of the pressure relief part is too large, but the length or width of the pressure relief body is very small, making it difficult for the pressure relief part to explode; at the same time, it can also effectively avoid that the thickness of the pressure relief part is too small. , and the length or width of the pressure relief body is too large, which leads to high processing accuracy requirements and increases the difficulty of production. This provides guidance for the production of pressure relief mechanisms.

The battery cells disclosed in the embodiments of the present application can be used in, but are not limited to, electrical devices such as vehicles, ships, or aircrafts. The power supply system of the electrical device can be composed of battery cells and batteries disclosed in this application, which can not only ensure effective explosion, but also reduce the difficulty of production and provide guidance for the production of pressure relief mechanisms.

Embodiments of the present application provide an electrical device that uses a battery as a power source. The electrical device may be, but is not limited to, a mobile phone, a tablet, a laptop, an electric toy, an electric tool, a battery car, an electric vehicle, a ship, a spacecraft, etc. Among them, electric toys can include fixed or mobile electric toys, such as game consoles, electric car toys, electric ship toys, electric airplane toys, etc., and spacecraft can include airplanes, rockets, space shuttles, spaceships, etc.

For the convenience of explanation in the following embodiments, an electrical device in an embodiment of the present application is a vehicle 10000 as an example.

Please refer to Figure 1, which is a schematic structural diagram of a vehicle 10000 provided by some embodiments of the present application. The vehicle 10000 can be a fuel vehicle, a gas vehicle or a new energy vehicle, and the new energy vehicle can be a pure electric vehicle, a hybrid vehicle or an extended-range vehicle, etc. The battery 1000 is disposed inside the vehicle 10000, and the battery 1000 may be disposed at the bottom, head, or tail of the vehicle 10000. The battery 1000 may be used to power the vehicle 10000 , for example, the battery 1000 may be used as an operating power source for the vehicle 10000 . The vehicle 10000 may also include a controller 2000 and a motor 3000. The controller 2000 is used to control the battery 1000 to provide power to the motor 3000, for example, to meet the power requirements for starting, navigation and driving of the vehicle 10000.

In some embodiments of the present application, the battery 1000 can not only be used as an operating power source for the vehicle 10000, but also can be used as a driving power source for the vehicle 10000, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 10000.

Please refer to FIG. 2 , which is an exploded view of the battery 1000 provided by some embodiments of the present application. The battery 1000 includes a case 200, a cover 300 and a battery cell 100. The battery cell 100 is accommodated in the case 200. The cover 300 and the box 200 cover each other, and the cover 300 and the box 200 jointly define an accommodation space for accommodating the battery cells 100 . The box 200 can be a hollow structure with one end open, and the cover 300 can be a plate-like structure. The cover 300 covers the open side of the box 200, so that the cover 300 and the box 200 jointly define an accommodation space; the cover 300 can be a hollow structure with one end open. 300 and the box body 200 can also be hollow structures with one side open, and the open side of the cover 300 is closed with the open side of the box body 200 . Of course, the box 200 formed by the cover 300 and the box 200 can be in various shapes, such as a cylinder, a rectangular parallelepiped, etc.

In the battery 1000, there may be multiple battery cells 100, and the multiple battery cells 100 may be connected in series, in parallel, or in mixed connection. Mixed connection means that the multiple battery cells 100 are connected in series and in parallel. Multiple battery cells 100 can be directly connected in series or in parallel or mixed together, and then the whole composed of multiple battery cells 100 can be accommodated in the box 200 ; of course, the battery 1000 can also be multiple battery cells 100 First, the battery 1000 modules are connected in series, parallel, or mixed to form a battery 1000 module. Then, multiple battery 1000 modules are connected in series, parallel, or mixed to form a whole, and are accommodated in the box 200 . The battery 1000 may also include other structures. For example, the battery 1000 may further include a bus component for realizing electrical connections between multiple battery cells 100 .

Each battery cell 100 may be a secondary battery or a primary battery; it may also be a lithium-sulfur battery, a sodium-ion battery or a magnesium-ion battery, but is not limited thereto. The battery cell 100 may be in the shape of a cylinder, a flat body, a rectangular parallelepiped or other shapes.

Please refer to FIG. 3 , which is an exploded structural diagram of a battery cell 100 provided in some embodiments of the present application. The battery cell 100 refers to the smallest unit that constitutes the battery 1000. As shown in FIG. 3 , the battery cell 100 includes an end cap 50 , a case 20 , an electrode assembly 40 and other functional components.

The end cap 50 refers to a component that covers the opening 22 of the case 20 to isolate the internal environment of the battery cell 100 from the external environment. Without limitation, the shape of the end cap 50 may be adapted to the shape of the housing 20 to fit the housing 20 . The end cap 50 can be made of a material with a certain hardness and strength (such as aluminum alloy). In this way, the end cap 50 is less likely to deform when subjected to extrusion and collision, so that the battery cell 100 can have higher structural strength and safety. Performance could also be improved. The end cap 50 may be provided with functional components such as electrode terminals. The electrode terminals may be used to electrically connect with the electrode assembly 40 for outputting or inputting electrical energy of the battery cell 100 . In some embodiments, the end cap 50 may also be provided with a pressure relief mechanism 10 for releasing the internal pressure when the internal pressure or temperature of the battery cell 100 reaches a threshold. The end cap 50 can also be made of various materials, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., which are not particularly limited in the embodiment of the present application. In some embodiments, an insulating member may be provided inside the end cover 50 , and the insulating member may be used to isolate the electrical connection components in the housing 20 from the end cover 50 to reduce the risk of short circuit. For example, the insulating member may be plastic, rubber, etc.

The case 20 is a component used to cooperate with the end cover 50 to form an internal environment of the battery cell 100 , wherein the formed internal environment can be used to accommodate the electrode assembly 40 , the electrolyte, and other components. The housing 20 and the end cover 50 may be independent components, and an opening 22 may be provided on the housing 20. The end cover 50 covers the opening 22 at the opening 22 to form the internal environment of the battery cell 100. Without limitation, the end cover 50 and the housing 20 can also be integrated. Specifically, the end cover 50 and the housing 20 can form a common connection surface before other components are put into the housing. When it is necessary to encapsulate the inside of the housing 20 When, the end cover 50 is closed with the housing 20 again. The housing 20 can be of various shapes and sizes, such as rectangular parallelepiped, cylinder, hexagonal prism, etc. Specifically, the shape of the housing 20 can be determined according to the specific shape and size of the electrode assembly 40 . The housing 20 may be made of a variety of materials, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., which are not particularly limited in the embodiments of the present application.

The electrode assembly 40 is a component in the battery cell 100 where electrochemical reactions occur. One or more electrode assemblies 40 may be contained within housing 20 . The electrode assembly 40 is mainly formed by winding or stacking positive electrode sheets and negative electrode sheets, and a separator is usually provided between the positive electrode sheets and the negative electrode sheets. The portions of the positive electrode sheet and the negative electrode sheet that contain active material constitute the main body of the electrode assembly 40 , and the portions of the positive electrode sheet and the negative electrode sheet that do not contain active material each constitute tabs. The positive electrode tab and the negative electrode tab can be located together at one end of the main body or respectively located at both ends of the main body. During the charging and discharging process of the battery 1000, the positive active material and the negative active material react with the electrolyte, and the tabs are connected to the electrode terminals to form a current loop.

According to some embodiments of the present application, please refer to FIG. 3 . The present application provides a pressure relief mechanism 10 . The pressure relief mechanism 10 includes: a pressure relief body 11 . The pressure relief body 11 extends along the first direction and the second direction respectively. The length of the pressure relief body 11 along the first direction is marked as L, and the width of the pressure relief body 11 along the second direction is marked as W. The pressure relief body 11 is provided with a pressure relief portion 12 . The thickness of the pressure relief portion 12 along the thickness direction of the pressure relief body 11 is denoted as δ, please refer to Figures 4 to 6 . The first direction, the second direction and the thickness direction of the pressure relief body 11 intersect each other; where, 0.0001≤δ/L≤1; and/or, 0.0001≤δ/W≤1.

For ease of understanding, taking Figure 3 as an example, the first direction is the direction pointed by the X arrow in Figure 3; the second direction is the direction pointed by the Y arrow in Figure 3; the thickness direction of the pressure relief body 11 is the direction Z in Figure 3 The direction the arrow points. The pressure relief main body 11 extends along the first direction and the second direction, and the first direction and the second direction intersect with the thickness direction of the pressure relief main body 11 respectively. Therefore, the pressure relief main body 11 extends in the first direction and the second direction. Extension design. Specifically, in some embodiments, the first direction is parallel to the length direction of the battery cell 100, and the second direction is parallel to the width direction of the battery cell 100.

The pressure relief body 11 refers to a component that brakes and relieves pressure after the internal air pressure or temperature of the battery cell 100 or battery 1000 reaches a certain threshold. It can be applied to the casing 20 of the battery cell 100 or directly applied to the battery. 1000 on the box 200. There are many shapes of the pressure relief body 11. For example, the shape of the pressure relief body 11 may be but not limited to rectangle, square, circle, oval or other linear designs. When the pressure relief body 11 is circular, its length and width can both be the diameter of the circle. When the pressure relief body 11 is elliptical, the length of the pressure relief body 11 can be the long axis of the ellipse, and the width of the pressure relief body 11 can be the short axis of the ellipse.

The pressure relief part 12 refers to a weak component on the pressure relief body 11; or a weak location component or a weak processing structural component. When the internal air pressure or temperature of the battery cell 100 or battery 1000 reaches a threshold, this structure will explode. When the pressure relief part 12 is a weak position component or a weak processing structural component, its thickness should be smaller than the thickness of the pressure relief body 11 except for the pressure relief part 12 . The pressure relief part 12 is a part of the pressure relief body 11 , so the obtained length or width of the pressure relief body 11 should include the length or width of the pressure relief part 12 .

The position distribution of the pressure relief portion 12 on the pressure relief body 11 can have various designs. For example, the pressure relief portion 12 can be located in the middle of the pressure relief body 11 or at the edge of the pressure relief body 11 . In some embodiments, the connection method of the pressure relief part 12 on the pressure relief body 11 may be, but is not limited to, welding or integral molding. Among them, integrated molding includes injection molding, die-casting, stamping, extrusion, etc.

During the design process, the length L of the pressure relief body 11 is usually 5 mm to 200 mm; the width W of the pressure relief body 11 is usually 5 mm to 200 mm. Of course, the above length L and width W are only to facilitate the specific implementation of the plan, but cannot This serves as a limitation on the scope of this proposal. The ratio between δ and L can be any value between 0.0001 and 1. For example: δ/L can be but not limited to 0.0001, 0.0005, 0.001, 0.0015, 0.002, 0.01, 0.03, 0.05, 0.07, 0.08, 0.1, 0.3, 0.5, 0.7, 0.9, 1, etc. Similarly, the ratio between δ and W can be any value between 0.0001 and 1. For example, δ/W can be but not limited to 0.0001, 0.0005, 0.001, 0.0015, 0.002, 0.01, 0.03, 0.05, 0.07, 0.08, 0.1, 0.3, 0.5, 0.7, 0.9, 1, etc.

Correlate at least one parameter of the length L along the first direction and the width W along the second direction with the thickness δ of the pressure relief portion 12 , and reasonably control the ratio between the two, so that the pressure relief mechanism 10 maintains a reasonable and effective Size parameters. In this way, when controlling the pressure relief performance, it can effectively avoid that the pressure relief part 12 is too thick, but the length or width of the pressure relief body 11 is very small, which makes the pressure relief part 12 difficult to explode; at the same time, it can also effectively avoid that the pressure relief part 12 is too thick. The thickness of 12 is too small, and the length or width of the pressure relief body 11 is too large, which results in excessive processing accuracy and increases manufacturing difficulty. This provides guidance for the production of the pressure relief mechanism 10 .

According to some embodiments of the present application, 0.0001≤δ/L≤0.1.

The ratio of the thickness δ of the pressure relief part 12 to the length L of the pressure relief body 11 is controlled to be between 0.0001 and 0.1. For example, δ/L can be but not limited to 0.0001, 0.0005, 0.001, 0.0015, 0.002, 0.01, 0.03, 0.05 ,0.07,0.08,0.1.

When δ/L>0.1, the thickness of the pressure relief part 12 is relatively large, but the length of the pressure relief body 11 is small, making it difficult to explode the pressure relief part 12; when δ/L<0.0001, the thickness of the pressure relief part 12 is thicker. The smaller the thickness, the higher the machining accuracy requirements, and the thickness control accuracy tends to become worse. If the length of the pressure relief body 11 is too long, this deterioration trend will be exacerbated.

For the convenience of explanation, pressure relief mechanisms 10 with different δ/L ratios were used for testing, and the obtained pressure relief effects are shown in Table 1.

Table 1

It can be seen from Table 1 that when the δ/L ratio is 2, the pressure relief part 12 cannot be flushed open, and effective pressure relief cannot be achieved.

Further optimizing the ratio of the thickness of the pressure relief part 12 to the length of the pressure relief body 11 can not only ensure that the pressure relief part 12 is exploded stably, but also reduce the manufacturing difficulty and cost.

According to some embodiments of the present application, 0.0001≤δ/W≤0.1.

The ratio of the thickness δ of the pressure relief part 12 to the width W of the pressure relief body 11 is controlled to be any value between 0.0001 and 0.1. For example, δ/W can be but not limited to 0.0001, 0.0005, 0.001, 0.0015, 0.002, 0.01, 0.03, 0.05, 0.07, 0.08, 0.1.

When δ/W>0.1, the thickness of the pressure relief part 12 is large, but the width of the pressure relief body 11 is small, making it difficult to explode the pressure relief part 12; when δ/W<0.0001, the thickness of the pressure relief part 12 is thicker The smaller the thickness, the higher the machining accuracy requirements, and the thickness control accuracy tends to become worse. If the width of the pressure relief body 11 is too large, this deterioration trend will be exacerbated.

For the convenience of explanation, pressure relief mechanisms 10 with different δ/W ratios were used for testing, and the obtained pressure relief effects are shown in Table 2.

Table 2

It can be seen from Table 2 that when the δ/W ratio is 2, the pressure relief part 12 cannot be flushed open, and effective pressure relief cannot be achieved.

Further optimizing the ratio of the thickness of the pressure relief part 12 to the width of the pressure relief body 11 can not only ensure that the pressure relief part 12 is exploded stably, but also reduce the manufacturing difficulty and cost.

According to some embodiments of the present application, the first direction and the second direction are arranged perpendicularly.

The first direction and the second direction are arranged perpendicularly, that is, the length L and width W of the pressure relief body 11 obtained are also vertically designed, which facilitates the acquisition of more accurate data and improves the pressure relief effect. For example: the pressure relief body 11 can be square or rectangular, etc. Specifically, in some embodiments, the first direction, the second direction and the thickness direction of the pressure relief body 11 are designed to be perpendicular to each other.

The first direction and the second direction are designed to be perpendicular to facilitate accurate acquisition of length and width data and improve the pressure relief performance of the pressure relief mechanism 10 .

According to some embodiments of the present application, please refer to FIG. 3 . The present application provides a battery cell 100 . The battery cell 100 includes a case 20, an electrode assembly 40, and a pressure relief mechanism 10 as in any of the above solutions. The housing 20 has an accommodating cavity 21 inside, and the housing 20 is provided with a pressure relief hole 23 communicating with the accommodating cavity 21 . The electrode assembly 40 is received in the containing cavity 21 . The pressure relief body 11 seals the pressure relief hole 23 .

The accommodating cavity 21 may have an opening 22 structure, that is, the end cover 50 covers the opening 22 of the accommodating cavity 21 to form a closed environment.

The position of the pressure relief hole 23 on the housing 20 can have various designs, for example: the pressure relief hole 23 is provided on the circumferential side of the housing 20; or is provided on the bottom of the housing 20, etc.

The sealing of the pressure relief hole 23 by the pressure relief body 11 should be understood as: before pressure relief occurs, the pressure relief hole 23 is in a closed state, and gas or liquid cannot be discharged out of the housing 20 through the pressure relief hole 23 . The installation method of the pressure relief body 11 in the pressure relief hole 23 may be, but is not limited to, bonding, welding, integrated molding, etc.

The above-mentioned battery cell 100 adopts the above pressure relief mechanism 10 and reasonably controls the ratio between the two, so that the pressure relief mechanism 10 maintains reasonable and effective size parameters. In this way, when controlling the pressure relief performance, it can effectively avoid that the pressure relief part 12 is too thick, but the length or width of the pressure relief body 11 is very small, which makes the pressure relief part 12 difficult to explode; at the same time, it can also effectively avoid that the pressure relief part 12 is too thick. The thickness of 12 is too small, and the length or width of the pressure relief body 11 is too large, which results in excessive processing accuracy and increases manufacturing difficulty. This provides guidance for the production of the pressure relief mechanism 10 .

According to some embodiments of the present application, please refer to Figure 4. This application provides a battery 1000. The battery 1000 includes a box 200, a battery cell 100 as in the above solution, and a support member 400. The battery cells 100 are accommodated in the box 200 . The support member 400 is disposed on the box 200 to support the battery cells 100 , and is provided with an exhaust hole 414 opposite to the pressure relief mechanism 10 .

The support member 400 is capable of supporting the battery cell 100 in the accommodation cavity 21 to ensure the structural stability of the battery 1000. The support member 400 may be a bottom plate structure of the battery 1000, or may be a water-cooling structure, or the like. When the support member 400 has a water-cooling structure, it can not only support the battery cell 100 but also provide a water-cooling effect on the battery cell 100 to ensure stable operation of the battery 1000.

The vent hole 414 refers to a structure that allows the gas inside the battery cell 100 to be discharged out of the battery 1000 through the pressure relief hole 23 and the vent hole 414 when the pressure relief part 12 is ruptured. The fact that the exhaust hole 414 is arranged opposite to the pressure relief mechanism 10 should be understood as: the exhaust hole 414 allows the gas discharged from the pressure relief mechanism 10 to flow out of the battery 1000 .

In order to facilitate the explosion or rupture of the pressure relief mechanism 10, a certain height should be reserved between the exhaust hole 414 and the pressure relief mechanism 10. For example, there should be a pressure relief space between the exhaust hole 414 and the pressure relief mechanism 10 to facilitate the leakage. The pressure part 12 deforms toward the exhaust hole 414 side to ensure that there is enough space below the pressure relief part 12 to achieve effective pressure relief.

The above-mentioned battery 1000 adopts the above pressure relief mechanism 10 and reasonably controls the ratio between the two, so that the pressure relief mechanism 10 maintains reasonable and effective size parameters. In this way, when controlling the pressure relief performance, it can effectively avoid that the pressure relief part 12 is too thick, but the length or width of the pressure relief body 11 is very small, which makes the pressure relief part 12 difficult to explode; at the same time, it can also effectively avoid that the pressure relief part 12 is too thick. The thickness of 12 is too small, and the length or width of the pressure relief body 11 is too large, which results in excessive processing accuracy and increases manufacturing difficulty. This provides guidance for the production of the pressure relief mechanism 10 .

According to some embodiments of the present application, please refer to Figures 2 and 3. The projected area of the pressure relief body 11 in the plane formed by the first direction and the second direction is marked as S. The opening area of the exhaust hole 414 is recorded as D; where, 0.005≤D/S≤10000.

Limiting the opening area of the exhaust hole 414 can allow the gas after pressure relief to flow into the exhaust hole 414, which is beneficial to improving the pressure relief effect of the pressure relief mechanism 10.

During the design process, the opening area D of the exhaust hole 414 is usually greater than 1 mm ² ; the projected area S of the pressure relief body 11 is usually 5 mm ² to 300 mm ² . The ratio between D/S can be any value between 0.005 and 10000. For example, D/S can be but not limited to 0.005, 0.1, 1, 10, 100, 1000, 10000, etc.

Reasonably control the ratio of the opening area D of the exhaust hole 414 to the projected area S of the pressure relief body 11 to ensure smooth exhaust after pressure relief; at the same time, it can also ensure that the battery cell 100 is stably supported and improve the overall structure of the battery 1000 mechanical properties.

According to some embodiments of the present application, 0.1≤D/S≤3000.

The ratio of the opening area D of the exhaust hole 414 to the projected area S of the pressure relief body 11 is controlled to be any value between 0.1 and 3000. For example, D/S can be but is not limited to 0.1, 1, 10, 100, 1000. , 2000, 3000, etc.

When D/S < 0.1, the reserved area of the support member 400 is small, and the exhaust is not smooth, and it is easy to block and cause the gas to release pressure from other locations; when D/S > 3000, the reserved area of the support member 400 is too large. The contact (bonding) area between the bottom of the battery cell 100 and the support member 400 is small, resulting in insufficient mechanical properties of the battery 1000 .

For the convenience of explanation, pressure relief mechanisms 10 with different D/S ratios were used for testing, and the obtained pressure relief effects are shown in Table 3.

table 3

编号serial number	电池1000泄压机构10的排气面积S(mm2)Exhaust area S (mm2) of the battery 1000 pressure relief mechanism 10	支撑构件400排气面积D(mm ²) Support member 400 exhaust area D (mm ² )	DSDS	达成的效果Achieved results
11	500500	500500	11	可正常泄压Can release pressure normally
22	100100	10001000	1010	可正常泄压Can release pressure normally
33	55	50005000	10001000	可正常泄压Can release pressure normally
44	55	0.10.1	0.020.02	泄压部12冲不开 Pressure relief part 12 cannot be opened

It can be seen from Table 3 that when the D/S ratio is 0.02, the pressure relief part 12 cannot be flushed open, and effective pressure relief cannot be achieved.

Further optimizing the ratio of the opening area D of the exhaust hole 414 to the projected area S of the pressure relief body 11 can not only ensure smooth exhaust, but also ensure sufficient support of the support member 400 and improve the mechanical properties of the battery 1000.

According to some embodiments of the present application, please refer to FIGS. 4 and 5 , the support member 400 is a water-cooling member 410 . The water-cooling component 410 is provided with a water-cooling flow channel 413.

The water-cooling component 410 can provide cooling water to circulate, so as to effectively transfer the heat on the battery cell 100 and discharge it out of the battery 1000 to achieve cooling. The structure of the water-cooling component 410 may be, but is not limited to, a harmonica-type structure, a water pipe, and other structures.

The support member 400 is designed as a water-cooling member 410, which can not only support the battery cell 100, but also provide a water-cooling effect on the battery cell 100 to ensure stable operation of the battery 1000.

According to some embodiments of the present application, please refer to FIG. 6 , the water cooling component 410 includes a first water cooling component 411 and a second water cooling component 412 . The first water-cooling component 411 and the second water-cooling component 412 are bonded together, and a water-cooling channel 413 is formed between them. The battery cell 100 is supported on the first water cooling component 411 . The pressure relief mechanism 10 is provided on a side of the battery cell 100 facing the first water-cooling component 411 , and the exhaust hole 414 penetrates the first water-cooling component 411 and the second water-cooling component 412 .

The connection method between the first water-cooling component 411 and the second water-cooling component 412 may be, but is not limited to, bolted connection, pin connection, bonding, welding, riveting, one-piece molding, etc.

The water-cooling component 410 is designed into two parts: a first water-cooling part 411 and a second water-cooling part 412, which makes the production of the water-cooling flow channel 413 more convenient.

According to some embodiments of the present application, please refer to FIG. 6 , the support member 400 further includes an insulating layer 415 . The insulating layer 415 is provided to close the exhaust hole 414.

The insulating layer 415 may be located on the side of the supporting member 400 facing the battery cell 100 , or may be located on the side of the supporting member 400 facing away from the battery cell 100 .

There are many ways to implement the insulating layer 415 to seal the vent hole 414. For example, the insulating layer 415 is sealed on the vent hole 414 by welding or bonding.

The exhaust hole 414 is closed by the insulating layer 415 to prevent liquid or air leakage from the exhaust hole 414 .

According to some embodiments of the present application, the present application provides an electrical device, including the battery 1000 in any of the above solutions. The battery 1000 is used to provide electrical energy.

According to some embodiments of the present application, please refer to Figures 2 to 6. This application provides a relationship between the thickness design of the weak part of the battery 1000 and the length of the pressure relief mechanism 10. The length of the pressure relief mechanism 10 of the battery 1000 (parallel to the battery 1000 length direction) is L, the width of the pressure relief mechanism 10 of the battery 1000 (parallel to the width direction of the battery 1000) is W, and the thickness of the weak portion of the pressure relief mechanism 10 is δ. Among them, 0.0001≤δ/L≤1; 0.0001≤δ/W≤1; preferably, 0.0001≤δ/L≤0.1; 0.0001≤δ/W≤0.1.

In order to allow the pressure relief mechanism 10 to release pressure normally when the battery 1000 is out of control, the bottom support member 400 generally considers reserving a turning height and an exhaust height for triggering the battery 1000 . There is a certain relationship between the reserved exhaust area of the support member 400 and the exhaust area of the pressure relief mechanism 10 of the battery 1000. The area of the pressure relief mechanism 10 of the battery 1000 is S, and the exhaust area of the support member 400 is D. Among them, 0.005≤D/S≤10000; preferably, 0.1≤D/S≤3000.

Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present application, but not to limit it; 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: The technical solutions described in the foregoing embodiments can still be modified, or some or all of the technical features can be equivalently replaced; and these modifications or substitutions do not deviate from the essence of the corresponding technical solutions from the technical solutions of the embodiments of the present application. The scope shall be covered by the claims and description of this application. In particular, as long as there is no structural conflict, the technical features mentioned in the various embodiments can be combined in any way. The application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

A pressure relief mechanism including:

A pressure relief body, the length of the pressure relief body along the first direction is marked as L, and the width of the pressure relief body along the second direction is marked as W; the pressure relief body has a pressure relief portion, and the pressure relief portion The thickness along the thickness direction of the pressure relief body is recorded as δ, and the first direction, the second direction and the thickness direction of the pressure relief body intersect each other;

Among them, 0.0001≤δ/L≤1; and/or, 0.0001≤δ/W≤1.
The pressure relief mechanism according to claim 1, wherein 0.0001≤δ/L≤0.1.
The pressure relief mechanism according to claim 1, wherein 0.0001≤δ/W≤0.1.
The pressure relief mechanism according to any one of claims 1-3, wherein the first direction and the second direction are arranged perpendicularly.
A battery cell, including:

A housing with an accommodating cavity inside, and the housing is provided with a pressure relief hole connected to the accommodating cavity;

An electrode assembly is received in the containing cavity;

The pressure relief mechanism according to any one of claims 1 to 4, wherein the pressure relief body seals the pressure relief hole.
A battery, including:

box;

The battery cell according to claim 5, housed in the box;

A support member is provided on the box and supports the battery cell, and is provided with an exhaust hole opposite to the pressure relief mechanism.
The battery according to claim 6, wherein the projected area of the pressure relief body in the plane formed by the first direction and the second direction is denoted as S, and the opening area of the exhaust hole is denoted as D;

Among them, 0.005≤D/S≤10000.
The battery according to claim 7, wherein 0.1≤D/S≤3000.
The battery according to any one of claims 6 to 8, wherein the support member is a water-cooling member, and a water-cooling flow channel is provided in the water-cooling member.
The battery according to claim 9, wherein the water-cooling component includes a first water-cooling component and a second water-cooling component, the first water-cooling component and the second water-cooling component are in contact with each other, and there is a gap formed between them. The water-cooling flow channel, the battery cell is supported on the first water-cooling component, the pressure relief mechanism is provided on a side of the battery cell facing the first water-cooling component, and the exhaust hole penetrates the The first water-cooling component and the second water-cooling component.
The battery according to any one of claims 6 to 10, wherein the support member further includes an insulating layer, the insulating layer closing the vent hole.
An electrical device, which includes the battery according to any one of claims 6 to 11, and the battery is used to provide electrical energy.