CN115036643B

CN115036643B - Battery monomer, battery and consumer

Info

Publication number: CN115036643B
Application number: CN202210965033.4A
Authority: CN
Inventors: 刘文忠; 白花蕾; 谢勇锋; 周文林; 李全坤
Original assignee: Contemporary Amperex Technology Co Ltd; Jiangsu Contemporary Amperex Technology Ltd
Current assignee: Contemporary Amperex Technology Co Ltd; Jiangsu Contemporary Amperex Technology Ltd
Priority date: 2022-08-12
Filing date: 2022-08-12
Publication date: 2022-12-02
Anticipated expiration: 2042-08-12
Also published as: CN115036643A; CN115832604A

Abstract

The application relates to a battery monomer, battery and consumer, battery monomer includes: a housing having a first wall; the pressure relief piece is arranged on the first wall; the insulating part comprises a connecting part and a protecting part which are arranged in a split mode, the connecting part is connected to the first wall, the protecting part is arranged on the connecting part or the first wall, and in the thickness direction of the first wall, the orthographic projection of the protecting part is at least partially overlapped with the orthographic projection of the pressure relief part; wherein the protection member is configured to be at least partially separated from the connector or the first wall when the pressure relief member is relieved. The connecting piece and the protection piece are designed in a split mode, so that the connecting piece can ensure that the insulating piece is stably connected with the first wall, and the situation that the pressure relief piece cannot be effectively protected due to the fact that the insulating piece is separated from the first wall is avoided; the protection piece can effectively protect the corresponding battery monomer, and avoid thermal runaway of other battery monomers around the battery monomer caused by thermal runaway of a certain battery monomer, thereby causing the problem of thermal diffusion.

Description

Battery monomer, battery and consumer

Technical Field

The application relates to the technical field of batteries, in particular to a battery monomer, a battery and electric equipment.

Background

As the application of battery technology in daily life becomes more and more extensive, the safety performance of the battery is also more and more emphasized. Generally, the safety problem of the battery is caused by thermal runaway, and during the use of the battery, various chemical reactions occur in each battery cell, and a large amount of gas is generated, so that the internal pressure of the battery cell is increased. Therefore, in order to prevent the explosion of the battery due to the excessively high internal pressure of the battery cell, a pressure relief member is generally provided at the top of the battery cell inside the battery.

However, although the pressure relief member can solve the problem of pressure relief inside the battery cell, when a certain battery cell or a part of the battery cells is thermally out of control, the ejected high-temperature substance easily affects other surrounding battery cells which normally operate, and causes thermal runaway of other battery cells, resulting in thermal diffusion, thereby affecting the overall safety performance of the battery.

Disclosure of Invention

In view of this, it is necessary to provide a battery cell, a battery, and an electric device, which are capable of solving the problem that the overall safety of the battery is affected by the thermal diffusion when the battery cell is thermally runaway.

In a first aspect, the present application provides a single battery cell, including a case, a pressure relief member, and an insulating member, where the case has a first wall, and the pressure relief member is disposed on the first wall; the insulating part comprises a connecting part and a protecting part which are arranged in a split mode, the connecting part is connected to the first wall, the protecting part is arranged on the connecting part or the first wall, and in the thickness direction of the first wall, the orthographic projection of the protecting part is at least partially overlapped with the orthographic projection of the pressure relief part; wherein the protection member is configured to be at least partially separated from the connector or the first wall when the pressure relief member is relieved.

Through above-mentioned structure, carry out the components of a whole that can function independently setting with connecting piece and protection piece, compare in the scheme of integrative setting, the components of a whole that can function independently setting can be convenient for adopt different materials or structure respectively to make connecting piece and protection piece, on the one hand, can practice thrift the cost, and on the other hand can realize the stable connection of connecting piece and first wall and the high-efficient protection of protection piece to the piece of leaking respectively through setting up different materials, both do not influence each other.

In some embodiments, the connecting member is provided with a through hole, the through hole is at least partially opposite to the pressure relief member in the thickness direction of the first wall, and the protection member is arranged on the connecting member and covers the through hole.

Therefore, the through holes can enable the high-pressure gas inside the single battery to be smoothly discharged out of the single battery when the pressure in the single battery is too high, smooth pressure relief of the single battery is ensured, and explosion of the single battery is avoided.

In some embodiments, the protection member is disposed on a side of the connecting member away from the first wall, a surface of the protection member facing the connecting member is disposed with an adhesive, and the protection member is disposed on the connecting member and covers the through hole through the adhesive.

The mode of connecting through the colloid can make the connection structure between protection piece and the connecting piece simpler to make protection piece and the quick and safe separation of connecting piece under the pressure effect in the battery monomer, ensure the smooth pressure release of battery monomer.

In some embodiments, the connecting member has a first gap and a second gap, the first gap and the second gap are spaced apart from each other along the first direction, and opposite ends of the protecting member respectively penetrate through the first gap and the second gap.

The protection piece can be stably connected with the connecting piece through the mode of penetrating through the first gap and the second gap.

In some embodiments, the connecting member is provided with a through hole, the first gap and the second gap are respectively located at two opposite ends of the through hole along the first direction, two opposite ends of the protecting member respectively penetrate through the first gap and the second gap, and the protecting member covers the through hole. Therefore, after the protection piece penetrates through the first gap and the second gap, the protection piece can stably cover the through hole, and the pressure relief piece is effectively protected.

In some embodiments, the protective member is over and covers the through-hole. Namely, the protection piece firstly penetrates through the first gap from bottom to top and covers the through hole, and then penetrates through the second gap from top to bottom, so that the protection piece is stably connected with the connecting piece. When the surrounding battery cells spray high-temperature substances, the protection member can better prevent the high-temperature substances from flowing into the battery cells through the through holes, so that the protection effect is improved.

In some embodiments, the first wall is provided with a pressure relief hole, and the protection member is connected to the first wall and covers the pressure relief hole. Therefore, the protection piece can protect the corresponding pressure relief piece more accurately, and the protection efficiency is improved.

In some embodiments, the first wall has a protrusion surrounding the pressure relief hole, and the protector is adhered to the protrusion and covers the pressure relief hole. The protrusion can prevent high-temperature substances or other external substances on the first wall from entering the pressure relief hole from the connecting gap between the protection member and the first wall, so that the pressure relief member can be further protected.

In some embodiments, the first wall is provided with a pressure relief hole, and the pressure relief element closes the pressure relief hole and is positioned on one side of the first wall far away from the insulating element; the battery monomer includes the protection paster, and the protection paster covers the pressure release hole and is located the pressure release piece top, and the protection piece pastes and locates on the protection paster. Realize the duplicate protection to the pressure release piece through protection piece and protection paster jointly, improve the security performance.

In some embodiments, the protection member is attached to a side surface of the connector facing the first wall. Therefore, on the basis of ensuring that the protective piece effectively protects the pressure relief piece, the connecting structure between the connecting piece and the protective piece can be simplified as much as possible, so that the whole structure is simpler and the operation is convenient.

In some embodiments, the protective member is adhered to the first wall by glue. The mode of connecting through the colloid can make the connection structure between protection piece and the first wall simpler to make protection piece and the quick and safe separation of first wall under the pressure effect in the battery monomer, ensure the smooth pressure release of battery monomer.

In some embodiments, a weakening is provided in the connector, the weakening being provided around at least part of the edge of the protector. The weak part can ensure that high-temperature substances generated by thermal runaway of the battery monomer can more easily break through the connecting piece, thereby smoothly realizing pressure relief.

In some embodiments, the material of the connecting member includes one of a polycarbonate substrate, a polypropylene substrate, and a polyethylene terephthalate substrate, which can be beneficial to improve the connection strength and connection stability between the connecting member and the first wall.

In some embodiments, the protection member is made of a high temperature resistant heat insulating material, so that the protection effect of the protection member on the pressure relief member can be improved, and the normal operation of the pressure relief member can be ensured.

In some embodiments, the material of the protection member includes one of glass fiber, mica, ceramic, and ceramic rubber.

In some embodiments, the first wall is an end cap that covers the opening of the housing.

In some embodiments, the battery cell includes an electrical core assembly housed within the housing.

In a second aspect, the present application provides a battery comprising a battery cell as described above.

In a third aspect, the present application provides an electric device, which includes an electric main body and the battery cell as described above.

The battery monomer, the battery and the electric equipment divide the insulating part into two parts, namely a connecting part and a protecting part, wherein the connecting part is used for being stably connected with the first wall, the protecting part is used for protecting the position of the pressure relief part on the first wall, namely the part of the insulating part used for protecting the pressure relief part and the part connected with the first wall are designed in a split mode, so that the connecting part and the protecting part can be made of different materials respectively, therefore, the connecting part can ensure that the insulating part is stably connected with the first wall, the situation that the pressure relief part cannot be effectively protected due to the separation of the insulating part and the first wall is avoided, in addition, the protecting part can effectively protect the pressure relief part on the battery monomer corresponding to the protecting part, and the problem that other battery monomers around generate thermal runaway and further cause thermal diffusion due to the thermal runaway of one battery monomer is avoided.

Drawings

FIG. 1 is a schematic structural diagram of a vehicle according to an embodiment of the present application;

fig. 2 is an exploded view of a battery according to an embodiment of the present disclosure;

fig. 3 is an exploded view of a battery cell according to an embodiment of the present disclosure;

fig. 4 is a schematic structural diagram of a battery cell according to an embodiment of the present application;

FIG. 5 is an exploded view of a first wall according to an embodiment of the present application;

FIG. 6 is a partial cross-sectional view of a first wall of an embodiment of the present application;

FIG. 7 is a schematic plan view of an insulator according to an embodiment of the present application;

FIG. 8 isbase:Sub>A cross-sectional view taken along line A-A of FIG. 7;

FIG. 9 is an enlarged view of a portion of FIG. 8 at B;

fig. 10 is a schematic structural diagram of a battery cell according to another embodiment of the present application;

FIG. 11 is a schematic view of an insulator according to another embodiment of the present application;

FIG. 12 is a bottom view of an insulator according to another embodiment of the present application;

FIG. 13 is a cross-sectional view taken along line C-C of FIG. 12;

FIG. 14 is an enlarged view of a portion of FIG. 13 at D;

FIG. 15 is a partial cross-sectional view of a first wall of an embodiment of the present application;

FIG. 16 is an exploded view of a first wall of another embodiment of the present application;

FIG. 17 is a partial cross-sectional view of a first wall of another embodiment of the present application;

FIG. 18 is an exploded view of an insulator according to an embodiment of the present application;

in the figure: 1000. a vehicle; 100. a battery; 200. a controller; 300. a motor; 10. a box body; 20. a battery cell; 30. a colloid; 11. a first portion; 12. a second portion; 21. a first wall; 22. a housing; 23. a battery cell assembly; 24. releasing the pressure; 25. an insulating member; 26. a protective patch; 211. a pressure relief vent; 212. a protrusion; 251. a connecting member; 252. a protective member; 2511. a through hole; 2512. a first slit; 2513. a second slit; 2514. a weakened portion; 21a, electrode terminals; a. a first direction.

Detailed Description

In order to make the aforementioned objects, features and advantages of the present application more comprehensible, embodiments accompanying figures are described in detail below. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present application. This application is capable of embodiment in many different forms than those described herein and those skilled in the art will be able to make similar modifications without departing from the spirit of the application and therefore the application is not limited to the specific embodiments disclosed below.

In the description of the present application, it is to be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," "circumferential," and the like are used in the orientations and positional relationships indicated in the drawings for convenience in describing the present application and for simplicity in description, and are not intended to indicate or imply that the referenced devices or elements must have a particular orientation, be constructed and operated in a particular orientation, and are therefore not to be considered limiting of the present application.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the feature. In the description of the present application, "plurality" means at least two, e.g., two, three, etc., unless specifically limited otherwise.

In this application, unless expressly stated or limited otherwise, the terms "mounted," "connected," "secured," and the like are to be construed broadly and can include, for example, fixed connections, removable connections, or integral parts; can be mechanically or electrically connected; they may be directly connected or indirectly connected through intervening media, or they may be connected internally or in any other suitable relationship, unless expressly stated otherwise. The specific meaning of the above terms in the present application can be understood by those of ordinary skill in the art as appropriate.

In this application, unless expressly stated or limited otherwise, the first feature "on" or "under" the second feature may be directly contacting the first and second features or indirectly contacting the first and second features through intervening media. Also, a first feature "on," "over," and "above" a second feature may be directly or diagonally above the second feature, or may simply indicate that the first feature is at a higher level than the second feature. A first feature "under," "beneath," and "under" a second feature may be directly under or obliquely under the second feature, or may simply mean that the first feature is at a lesser elevation than the second feature.

It will be understood that when an element is referred to as being "secured to" or "disposed on" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and the like as used herein are for illustrative purposes only and do not denote a unique embodiment.

At present, the application of power batteries is more and more extensive from the development of market conditions. The power battery is not only applied to energy storage power supply systems such as hydraulic power, firepower, wind power and solar power stations, but also widely applied to electric vehicles such as electric bicycles, electric motorcycles and electric automobiles, and a plurality of fields such as military equipment and aerospace. With the continuous expansion of the application field of the power battery, the market demand is also continuously expanded.

The power battery can be formed by arranging a plurality of battery monomers, the internal temperature of each battery monomer is continuously increased in the using process, and various chemical reactions occur in each battery monomer, so that a large amount of gas is generated, and the internal pressure of each battery monomer is increased.

In order to prevent the explosion of the battery due to the excessive internal pressure of the battery cell, a pressure relief member is generally provided at the top of the battery cell, and when the internal pressure of the battery cell increases to a certain degree, high-temperature gas inside the battery cell is discharged by being pushed out of the pressure relief member.

Since the battery is composed of a plurality of battery cells, when any one of the battery cells pushes the pressure relief member under the action of the internal pressure, the high-temperature substance in the battery cell is ejected together with the gas. Therefore, the high-temperature substances affect other surrounding battery cells which normally operate, for example, the high-temperature substances may fuse the pressure relief parts on the other surrounding battery cells, so that the structures of the other battery cells are damaged and the other battery cells cannot normally operate. Therefore, a corresponding heat insulation structure needs to be arranged for each battery cell, and high-temperature substances sprayed out of other battery cells are blocked through the heat insulation structure, so that the battery cells which normally work are effectively protected.

However, the present inventors have noted that the following problems exist with the current thermal insulation structure: on the basis of guaranteeing that thermal-insulated structure can effectively block high temperature material, because thermal-insulated structure self material restriction, can't compromise simultaneously effectively to high temperature material block and with the stable connection of the free end cover of battery, easy external factor influences down with the end cover separation to can't effectively protect battery monomer. On the contrary, if the close connection between the heat insulation structure and the end cover is ensured, the heat insulation effect is poor due to the limitation of the material of the heat insulation structure, so that the battery cell is easily affected by high-temperature substances from other battery cells around to fail, and the battery cell cannot be effectively protected.

Based on the above consideration, for effectively protecting the battery monomer, the inventor is through deep research, a battery monomer has been designed, through setting up connecting piece and protection piece components of a whole that can function independently, so that adopt different materials or structure to make respectively connecting piece and protection piece, realize the stable connection of connecting piece and end cover respectively, effectively protect the battery monomer that corresponds through protection piece simultaneously, make the battery monomer that corresponds can not receive the influence and the destruction that come from the free high temperature material of other batteries, ensure that the battery monomer that corresponds can normally work, thereby improve the whole security of battery.

The battery cell disclosed in the embodiment of the application can be used in electric devices such as vehicles, ships or aircrafts, and the electric device using the battery as a power supply can be but not limited to a mobile phone, a tablet, a notebook computer, an electric toy, an electric tool, a battery car, an electric automobile, a ship, a spacecraft and the like. The electric toy may include a stationary or mobile electric toy, such as a game machine, an electric car toy, an electric ship toy, an electric airplane toy, and the like, and the spacecraft may include an airplane, a rocket, a space shuttle, a spacecraft, and the like.

For convenience of description, the following embodiments take an electric device of an embodiment of the present application as an example of a vehicle 1000.

Referring to fig. 1, fig. 1 is a schematic structural diagram of a vehicle 1000 according to some embodiments of the present disclosure. The vehicle 1000 may be a fuel automobile, a gas automobile, or a new energy automobile, and the new energy automobile may be a pure electric automobile, a hybrid electric automobile, or an extended range automobile, etc. The battery 100 is provided inside the vehicle 1000, and the battery 100 may be provided at the bottom or the head or the tail of the vehicle 1000. The battery 100 may be used for power supply of the vehicle 1000, for example, the battery 100 may serve as an operation power source of the vehicle 1000. The vehicle 1000 may further include a controller 200 and a motor 300, the controller 200 being configured to control the battery 100 to supply power to the motor 300, for example, for starting, navigation, and operational power requirements while the vehicle 1000 is traveling.

In some embodiments of the present application, the battery 100 may be used not only as an operating power source of the vehicle 1000, but also as a driving power source of the vehicle 1000, instead of or in part of fuel or natural gas, to provide driving power for the vehicle 1000.

Referring to fig. 2, fig. 2 is an exploded view of a battery 100 according to some embodiments of the present disclosure. The battery 100 includes a case 10 and a battery cell 20, and the battery cell 20 is accommodated in the case 10. The case 10 is used to provide a receiving space for the battery cell 20, and the case 10 may have various structures. In some embodiments, the case 10 may include a first portion 11 and a second portion 12, the first portion 11 and the second portion 12 cover each other, and the first portion 11 and the second portion 12 together define a receiving space for receiving the battery cell 20. The second part 12 may be a hollow structure with an open end, the first part 11 may be a plate-shaped structure, and the first part 11 covers the open side of the second part 12, so that the first part 11 and the second part 12 jointly define a containing space; the first portion 11 and the second portion 12 may be both hollow structures with one side open, and the open side of the first portion 11 may cover the open side of the second portion 12. Of course, the case 10 formed by the first and

second portions

11 and 12 may have various shapes, such as a cylinder, a rectangular parallelepiped, and the like.

In the battery 100, the number of the battery cells 20 may be multiple, and the multiple battery cells 20 may be connected in series or in parallel or in series-parallel, where in series-parallel refers to both series connection and parallel connection among the multiple battery cells 20. The plurality of battery cells 20 can be directly connected in series or in parallel or in series-parallel, and the whole formed by the plurality of battery cells 20 is accommodated in the box body 10; of course, the battery 100 may also be formed by connecting a plurality of battery cells 20 in series, in parallel, or in series-parallel to form a battery module, and then connecting a plurality of battery modules in series, in parallel, or in series-parallel to form a whole, and the whole is accommodated in the box 10. The battery 100 may further include other structures, for example, the battery 100 may further include a bus member for achieving electrical connection between the plurality of battery cells 20.

Wherein each battery cell 20 may be a secondary battery or a primary battery; but is not limited to, a lithium sulfur battery, a sodium ion battery, or a magnesium ion battery. The battery cell 20 may be cylindrical, flat, rectangular parallelepiped, or other shapes.

Referring to fig. 3, fig. 3 is an exploded structural schematic diagram of a battery cell 20 according to some embodiments of the present disclosure. The battery cell 20 refers to the smallest unit constituting the battery. Referring to fig. 3, the battery cell 20 includes an end cap, a housing 22, a battery cell assembly 23, and other functional components.

The end cap refers to a member that covers an opening of the case 22 to insulate the internal environment of the battery cell 20 from the external environment. Without limitation, the shape of the end cap may be adapted to the shape of the housing 22 to fit the housing 22. Alternatively, the end cap may be made of a material (e.g., an aluminum alloy) having a certain hardness and strength, so that the end cap is not easily deformed when being extruded and collided, and thus the single battery 20 may have a higher structural strength and the safety performance may be improved. The end cap may be provided with functional components such as electrode terminals. The electrode terminals may be used to be electrically connected with the electric core assembly 23 for outputting or inputting electric power of the battery cell 20. In some embodiments, a pressure relief mechanism for relieving the internal pressure of the battery cell 20 when the internal pressure or temperature reaches a threshold value may also be provided on the end cap. The end cap may be made of various materials, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., which is not limited in this embodiment. In some embodiments, insulation may also be provided on the inside of the end caps, which may be used to isolate the electrical connection components within the housing 22 from the end caps to reduce the risk of shorting. Illustratively, the insulator may be plastic, rubber, or the like.

The housing 22 is an assembly for mating with end caps to form an internal environment for the cell 20, wherein the formed internal environment may be used to house the cell assembly 23, electrolyte, and other components. The housing 22 and the end caps may be separate components, and an opening may be provided in the housing 22, and the opening may be covered by the end cap to form the internal environment of the battery cell 20. Without limitation, the end cap and the housing 22 may be integrated, and specifically, the end cap and the housing 22 may form a common connecting surface before other components are inserted into the housing, and when it is necessary to enclose the inside of the housing 22, the end cap covers the housing 22. The housing 22 may be a variety of shapes and sizes, such as rectangular parallelepiped, cylindrical, hexagonal prism, etc. Specifically, the shape of the housing 22 may be determined according to the specific shape and size of the electric core assembly 23. The material of the housing 22 may be various materials, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., which is not limited in the embodiments of the present invention.

The cell assembly 23 is a component in which electrochemical reactions occur in the battery cell 20. One or more electrical core assemblies 23 may be contained within the housing 22. The core assembly 23 is mainly formed by winding or stacking a positive electrode sheet and a negative electrode sheet, and a separator is generally provided between the positive electrode sheet and the negative electrode sheet. The parts of the positive plate and the negative plate with the active substances form the main body part of the electric core assembly, and the parts of the positive plate and the negative plate without the active substances form the tabs respectively. The positive electrode tab and the negative electrode tab may be located at one end of the main body portion together or at both ends of the main body portion, respectively. During the charging and discharging process of the battery, the positive active material and the negative active material react with the electrolyte, and the tabs are connected with the electrode terminals to form a current loop.

Referring to fig. 4, 5 and 6, fig. 4 is a schematic structural view of a battery cell according to some embodiments of the present disclosure, fig. 5 is an exploded schematic view of a first wall according to some embodiments of the present disclosure, and fig. 6 is a partial sectional view of the first wall according to some embodiments of the present disclosure. An embodiment of the present application provides a battery cell 20 including a case 22, a pressure relief member 24, and an insulating member 25. Wherein the housing 22 has a first wall 21. A relief 24 is provided on the first wall 21. The insulation member 25 includes a connecting member 251 and a protection member 252, wherein the connecting member 251 is connected to the first wall 21, and the protection member 252 is disposed on the connecting member 251 or the first wall 21. In the thickness direction of the first wall 21, the orthogonal projection of the protector 252 at least partially overlaps the orthogonal projection of the pressure relief piece 24. Furthermore, the protector 252 is configured to be able to be at least partially separated from the connector 251 or the first wall 21 when the pressure relief member 24 is relieved.

It should be noted that, as a specific example, the first wall 21 may be configured as an end cap covering the opening of the housing 22. For convenience of explanation, the first wall 21 will be described below by taking an end cap as an example.

The connecting member 251 is configured as a plate-like structure having an outer contour identical to an outer contour of the first wall 21, and the protecting member 252 is configured as a plate-like structure provided on the connecting member 251 or the first wall 21. Further, the thickness direction of the first wall 21 refers to a distance between a surface of the first wall 21 facing the inside of the case 22 and a surface facing away from the case 22 when the first wall 21 is sealingly attached to the case 22 of the battery cell 20.

The connecting member 251 is disposed over the first wall 21 so as to be connected to the first wall 21. Specifically, the connecting member 251 may be adhered to the first wall 21 by gluing, a glue 30 is disposed on a side surface of the connecting member 251 facing the first wall 21, and the connecting member 251 is adhered to the first wall 21 by the glue 30.

It can be understood that the connecting member 251 may also be connected to the first wall 21 in other manners, for example, the connecting member 251 is fixed on the first wall 21 in a clamping manner to achieve stable connection therebetween, which is not described herein again.

Further, the pressure relief element 24 may be an explosion-proof valve disposed on the first wall 21, or may be disposed in another pressure relief structure, as long as the pressure relief inside the battery cell 20 can be achieved, which is not described herein.

The orthogonal projection of the protector 252 in the thickness direction of the first wall 21 at least partially overlaps the orthogonal projection of the pressure relief piece 24, and specifically, the protector 252 may be disposed to face the pressure relief piece 24, that is, the orthogonal projection of the protector 252 in the thickness direction of the first wall 21 just overlaps the orthogonal projection of the pressure relief piece 24. Of course, the protector 252 may also be provided so as to cover the bleeder 24, i.e., an orthographic projection of the protector 252 in the thickness direction of the first wall 21 covers an orthographic projection of the bleeder 24.

Thus, when the internal pressure of the battery cell 20 rises to a certain degree, the pressure can be released by the pressure release member 24. At this time, the protection member 252 and the pressure relief member 24 are separated from the connection member 251 or the first wall 21, respectively, by the impact of the gas inside the battery cell 20, so that the gas inside the battery cell 20 can be smoothly discharged.

With the above structure, the connecting member 251 and the protecting member 252 are separately provided, which facilitates manufacturing the connecting member 251 and the protecting member 252 with different materials or structures, respectively, compared to the case of integrally providing them. On the one hand, costs can be saved. On the other hand, the stable connection between the connecting member 251 and the first wall 21 and the efficient protection of the protecting member 252 on the pressure relief member 24 can be achieved by providing different materials, which do not affect each other. Specifically, when the high-temperature substance inside one battery cell 20 breaks through the pressure relief member 24 and is discharged, the pressure relief members 24 of other battery cells 20 around are not affected by the high-temperature substance under the blocking effect of the protective member 252, so that the other battery cells 20 around are effectively protected, and the safety performance of the overall structure of the battery 100 is improved.

Referring to fig. 7, 8 and 9 together, fig. 7 isbase:Sub>A plan view of an insulating member according to some embodiments of the present application, fig. 8 isbase:Sub>A sectional view taken alongbase:Sub>A-base:Sub>A direction in fig. 7, and fig. 9 isbase:Sub>A partial enlarged view taken at B in fig. 8. In some embodiments, the connecting member 251 has a through hole 2511, the through hole 2511 is at least partially disposed opposite to the pressure relief member 24 in the thickness direction of the first wall 21, and the protection member 252 is disposed on the connecting member 251 and covers the through hole 2511.

A through hole 2511 is provided in the connecting member 251, and the through hole 2511 is provided at least partially opposite to the pressure release member 24 in the thickness direction of the first wall 21. When the internal pressure of the battery cell 20 is too high and the internal gas breaks through the pressure relief piece 24, the arrangement of the through hole 2511 can enable the pressure relief piece 24 to be separated from the first wall 21 more smoothly, so that the battery cell 20 is ensured to be relieved smoothly, and explosion of the battery cell 20 is avoided.

The protection member 252 covers the through hole 2511, and on one hand, when the corresponding battery cell 20 of the protection member 252 normally operates, the protection member 252 can protect the battery cell 20 and the pressure relief member 24 thereon from being contaminated by high-temperature substances from the surrounding battery cells 20. On the other hand, when the internal pressure of the battery cell 20 corresponding to the protector 252 is too high and breaks the pressure relief member 24, the protector 252 is smoothly separated from the connector 251 to expose the through hole 2511, so that the high-pressure gas inside the battery cell 20 can be smoothly discharged through the through hole 2511.

In some embodiments of the present application, the protection element 252 is disposed on a side of the connecting element 251 away from the first wall 21, a surface of the protection element 252 facing the connecting element 251 is provided with the glue 30, and the protection element 252 is disposed on the connecting element 251 through the glue 30 and covers the through hole 2511.

Specifically, an orthographic projection of the protector 252 in the thickness direction of the first wall 21 covers the through hole 2511, that is, the area of the protector 252 is larger than the area of the through hole 2511. The adhesive 30 is provided at a position where the protector 252 overlaps the connector 251, and the protector 252 is adhered to the connector 251 through the adhesive 30 so as to cover the through hole 2511.

When the internal pressure of the battery cell 20 corresponding to the protection member 252 is too high, the high-temperature substance inside the battery cell 20 breaks through the pressure relief member 24 and the protection member 252 and is discharged from the through hole 2511, so that the pressure inside the battery cell 20 is smoothly relieved. Therefore, the protection member 252 is connected with the connecting member 251 in a manner of providing the colloid 30, so that the protection member 252 can be quickly and safely separated from the connecting member 251, and the single battery 20 can be smoothly decompressed.

Referring to fig. 10 together, fig. 10 is a schematic structural diagram of a battery cell according to some embodiments of the present disclosure. In some embodiments, the connecting member 251 has a first slit 2512 and a second slit 2513, and the first slit 2512 and the second slit 2513 are spaced apart from each other along the first direction a. Opposite ends of the protection member 252 are respectively inserted into the first gap 2512 and the second gap 2513.

The first direction a may be a length direction of the connecting member 251, or a width direction of the connecting member 251, and may be set correspondingly according to a penetrating direction of the protecting member 252.

Specifically, the protection member 252 and the connection member 251 can be connected by not only providing the colloid but also stably connecting the protection member 252 and the connection member by inserting the protection member 252 into the first gap 2512 and the second gap 2513.

When the protecting member 252 has a certain flexibility, the protecting member 252 may sequentially pass through the first gap 2512 and the second gap 2513 from inside to outside or from outside to inside, so that the protecting member 252 is fixedly connected to the connecting member 251, and the protecting member 252 covers the through hole 2511.

As shown in fig. 10, one end of the protecting member 252 firstly passes through the first gap 2512 from bottom to top, and then passes through the second gap 2513 from top to bottom, that is, two ends of the protecting member 252 are respectively located below the through hole 2511, and the middle portion of the protecting member 252 is located above the through hole 2511, and covers the through hole 2511 from above. When high-temperature substances generated by thermal runaway of the battery cell 20 are flushed out, the two ends of the protection member 252 can be separated from the first gap 2512 and the second gap 2513, so that the protection member 252 is separated from the connecting member 251, and the pressure of the battery cell 20 is relieved.

Referring to fig. 11 to 14, fig. 11 is a schematic structural view of an insulating member according to another embodiment of the present application, fig. 12 is a schematic plan view of the insulating member according to some embodiments of the present application, fig. 13 is a sectional view taken along the direction C-C in fig. 12, and fig. 14 is a partially enlarged view of the insulating member at the position D in fig. 13.

One end of the protection member 252 firstly passes through the first gap 2512 from top to bottom and then passes through the second gap 2513 from bottom to top, that is, two ends of the protection member 252 are respectively located above the through hole 2511, and the middle part of the protection member 252 is located below the through hole 2511 and covers the through hole 2511 from below.

It is understood that the protection member 252 may be fixedly connected to the connecting member 251 and cover the through hole 2511 by other methods, such as riveting, clamping, etc., which are not described herein.

In some embodiments of the present application, the first and

second slits

2512 and 2513 are located at opposite ends of the through-hole 2511 along the first direction a, respectively. Opposite ends of the protection member 252 are respectively inserted into the first gap 2512 and the second gap 2513, and the protection member 252 covers the through hole 2511. Therefore, after the protection member 252 penetrates through the first gap 2512 and the second gap 2513, the protection member can stably cover the through hole 2511, and the pressure relief member 24 can be effectively protected.

In some embodiments of the present application, when the opposite ends of the protection member 252 are respectively disposed through the first gap 2512 and the second gap 2513, the protection member 252 is disposed above the through hole 2511 and covers the through hole 2511. That is, the protection member 252 is first inserted through the first gap 2512 from bottom to top and covers the through hole 2511, and then inserted through the second gap 2513 from top to bottom, so as to achieve stable connection with the connecting member 251. Compared with the scheme that the protection member 252 is positioned below the through hole 2511, when the surrounding battery cells 20 spray high-temperature substances, the protection member 252 can better prevent the high-temperature substances from flowing into the battery cells 20 through the through holes, thereby improving the protection effect.

Referring to fig. 5 and 15 together, fig. 15 is a partial cross-sectional view of a first wall according to some embodiments of the present application. In some embodiments, the first wall 21 defines a pressure relief hole 211, and the protection member 252 is connected to the first wall 21 and covers the pressure relief hole 211.

When the connecting member 251 is disposed on the first wall 21, the protecting member 252 can be disposed on the first wall 21 at the same time. Specifically, the pressure relief member 24 is disposed in the pressure relief hole 211, and connects the protector 252 to the first wall 21 and covers the pressure relief hole 211.

Therefore, when the internal pressure of the battery cell 20 corresponding to the protector 252 is too high, the internal air pressure can burst the pressure relief member 24 and the protector 252 and be discharged from the pressure relief hole 211. In addition, when the corresponding battery cell 20 of the protection member 252 normally operates, the protection member 252 can also block high temperature substances from other battery cells 20, so as to prevent the high temperature substances from contaminating the pressure relief member 24 and entering the inside of the battery cell 20 through the pressure relief hole 211.

In some embodiments of the present disclosure, the first wall 21 has a protrusion 212, the protrusion 212 is disposed around the pressure relief hole 211, and the protection member 252 is adhered to the protrusion 212 and covers the pressure relief hole 211. The protrusion 212 can prevent high temperature substances or other foreign substances on the first wall 21 from entering into the pressure relief hole 211 from the connection gap between the protector 252 and the first wall 21, thereby further protecting the pressure relief member 24.

Referring to fig. 16 and 17 together, fig. 16 is an exploded view of a first wall according to some embodiments of the present disclosure, and fig. 17 is a partial cross-sectional view of the first wall according to some embodiments of the present disclosure. In some embodiments, the first wall 21 defines a pressure relief hole 211, and the pressure relief element 24 closes the pressure relief hole 211 and is located on a side of the first wall 21 away from the insulator 25. The battery cell 20 includes a protection patch 26, the protection patch 26 covers the pressure relief hole 211 and is located above the pressure relief member 24, and the protection member 252 is attached to the protection patch 26.

Specifically, the protective patch 26 may be provided as a transparent PET (Polyethylene terephthalate substrate) patch or a PP (Polypropylene) patch or the like. In some embodiments, when the protection patch 26 is covered over the pressure relief member 24, the protection member 252 may be attached to the protection patch 26, thereby providing dual protection for the pressure relief member 24 and the battery cell 20 together with the protection patch 26.

Referring to fig. 18, fig. 18 is an exploded view of an insulator according to some embodiments of the present application. In some embodiments, the protection member 252 is attached to a side surface of the connecting member 251 facing the first wall 21. Specifically, since the high-temperature substance inside the battery cell 20 is pushed out of the pressure relief hole 211 by the internal pressure and sufficiently melts the connector 251, the protector 252 can be directly attached to the surface of the connector 251 facing the first wall 21. When the high-temperature substance is flushed out from the inside of the battery cell 20, the connection member 251 is melted, and thus the protection member 252 is separated from the connection member 251, so that the high-temperature substance is smoothly discharged out of the battery cell 20.

In some embodiments of the present application, the protection member 252 is adhered to the first wall 21 by the glue 30. The connection structure between the protection member 252 and the first wall 21 is simpler by the connection of the colloid 30, and the protection member 252 is quickly and safely separated from the first wall 21 under the action of the internal pressure of the battery cell 20, so that the smooth pressure relief of the battery cell 20 is ensured.

Further, a weakened portion 2514 is provided on the connector 251, the weakened portion 2514 providing the protector 252 around at least part of the edge of the protector. Specifically, the weak portion 2514 may be configured as a discontinuous hole opened on the connector 251 around at least a portion of the edge of the protector 252, and the high-pressure gas inside the battery cell 20 can break the connector 251 along the weak portion 2514, thereby smoothly discharging the high-pressure gas. Accordingly, the weak portion 2514 can ensure that the high-temperature substance generated by thermal runaway of the battery cell 20 can more easily break through the connector 251, thereby smoothly achieving pressure relief.

In addition, the weakened portion 2514 may also be provided as a recessed portion on the connector 251, i.e., the weakened portion 2514 is formed by at least a portion of the edge of the connector 251 that is recessed inwardly around the protector 252. Since the thickness of the weak portion 2514 is smaller than the thickness of the other portions, the weak portion 2514 is more easily broken by the high-pressure gas inside the battery cell 20, and the high-pressure gas is smoothly discharged. Of course, the weak portion 2514 may be provided with other structures, such as a slit structure, so that the connecting element 251 is disconnected from the position under the action of the high-pressure gas, and the high-pressure gas can be smoothly discharged, which will not be described herein.

In some embodiments, the material of the connecting member 251 includes one of a polycarbonate substrate, a polypropylene substrate, and a polyethylene terephthalate substrate.

The polycarbonate substrate, the polypropylene substrate, and the polyethylene terephthalate substrate can make the connecting member 251 stably connected with the first wall 21 more smoothly, and when the protection member 252 is disposed on the connecting member 251 and fixed on the first wall 21 through the connecting member 251, the connecting member 251 can be prevented from being separated from the first wall 21 by an external force due to the tight connection between the connecting member 251 and the first wall 21, so that the protection member 252 thereon can effectively protect the pressure relief member 24 and the battery cell 20.

It is understood that, in some other embodiments, the connection member 251 may be made of other materials besides the above materials, which is only required to ensure that the connection member 251 is stably connected to the first wall 21, and the description thereof is omitted here.

Since the connection member 251 and the protection member 252 do not function the same, the connection member 251 serves to achieve stable connection with the first wall 21, and the protection member 252 serves to protect the pressure relief member 24 and the battery cell 20. Therefore, the material of the protection member 252 is different from that of the connection member 251.

In some embodiments, the protection member 252 is made of a high temperature resistant insulating material.

The high-temperature-resistant heat insulating material is a material that can withstand a temperature of 800 ℃. Therefore, the protection member 252 can prevent the high-temperature substance from damaging the structure of the battery cell, and ensure that the battery cell can normally operate.

In some embodiments, the material of the protection member 252 includes one of glass fiber, mica, and ceramic rubber. For example, the protection member 252 may be provided as a mica sheet made of mica, and cover the through hole 2511 or the pressure relief hole 211. It is understood that the material of the protection member 252 may be other high temperature resistant and fireproof materials, which are not described in detail herein.

In some embodiments, the battery cell 20 further includes a battery core assembly 23 housed within the housing 22.

Based on the same concept as the battery cell 20 described above, the present application also provides a battery including the battery cell 20 as described above.

Based on the same concept as the battery cell 20, the present application also provides an electric device, which includes an electric main body and the battery cell 20.

When the battery cell 20 is applied to the electric main body, if the internal pressure of any one of the battery cells 20 is too high, the high-pressure gas inside the battery cell breaks through the pressure relief member 24 on the first wall 21 and the protector 252 covering the pressure relief member 24 together with the high-temperature substance, and is discharged from the pressure relief hole 211 or the through hole 2511 on the connector 251.

At this time, the protection member 252 covering the pressure relief member 24 of the other battery cells 20 around can block the high-temperature substances, and prevent the battery cells 20 from being polluted by the high-temperature substances, so that the corresponding battery cells 20 can normally work, the overall safety performance of the battery 100 is improved, and the overall safety performance of the electric equipment is improved.

When the battery pack is used specifically, the connecting member 251 is attached to the first wall 21 of the corresponding battery cell 20, so that the connecting member is stably connected to the first wall 21. Further, the protector 252 is disposed on the connector 251 and covers the through hole 2511, or the protector 252 is sealed in the pressure relief hole 211 of the first wall 21.

When the internal pressure of one of the battery cells 20 is too high, the high-pressure gas inside the cell breaks through the pressure relief member 24 on the first wall 21 and the protector 252 covering the pressure relief member 24 together with the high-temperature substance, and is discharged from the pressure relief hole 211 or the through hole 2511 in the connecting member 251.

At this time, the protection member 252 covering the pressure relief member 24 of the other battery cells 20 around can block the high temperature substances, and prevent the corresponding battery cell 20 from being polluted by the high temperature substances, thereby ensuring that the corresponding battery cell 20 can normally work and improving the overall safety performance of the battery 100.

The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.

The above-mentioned embodiments only express several embodiments of the present application, and the description thereof is more specific and detailed, but not construed as limiting the claims. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the concept of the present application, and these are all within the scope of protection of the present application. Therefore, the protection scope of the present patent shall be subject to the appended claims.

Claims

1. A battery cell, comprising:

the pressure relief device comprises a shell, a pressure relief valve and a pressure relief valve, wherein the shell is provided with a first wall, and the first wall is provided with a pressure relief hole;

the pressure relief piece is arranged on the first wall and closes the pressure relief hole;

the protective patch covers the pressure relief hole and is positioned above the pressure relief piece; and

the insulating piece comprises a connecting piece and a protecting piece which are arranged in a split mode, the connecting piece is connected to the first wall, the protecting piece is arranged on the connecting piece or the first wall, and in the thickness direction of the first wall, the orthographic projection of the protecting piece is at least partially overlapped with the orthographic projection of the pressure relief piece;

wherein the protector is configured to be at least partially separated from the connector or the first wall when the pressure relief member is depressurized.

2. The battery cell as recited in claim 1, wherein the connecting member has a through hole formed therein, the through hole being at least partially disposed opposite to the pressure relief member in a thickness direction of the first wall, and the protector member is disposed on the connecting member and covers the through hole.

3. The battery cell as recited in claim 2, wherein the protection member is disposed on a side of the connecting member away from the first wall, a surface of the protection member facing the connecting member is provided with a sealant, and the protection member is disposed on the connecting member through the sealant and covers the through hole.

4. The battery cell as recited in claim 1, wherein the connecting member defines a first gap and a second gap, the first gap and the second gap are spaced apart from each other along a first direction, and opposite ends of the protection member respectively penetrate through the first gap and the second gap.

5. The battery cell as recited in claim 4, wherein the connecting member has a through hole, the first slit and the second slit are respectively located at two opposite ends of the through hole along the first direction, two opposite ends of the protection member respectively penetrate through the first slit and the second slit, and the protection member covers the through hole.

6. The battery cell as recited in claim 5 wherein the protective member is over and covers the through-hole.

7. The battery cell as claimed in claim 1, wherein the first wall has a pressure relief hole, and the protector is connected to the first wall and covers the pressure relief hole.

8. The battery cell as recited in claim 7, wherein the first wall has a protrusion, the protrusion surrounds the pressure relief hole, and the protector is adhered to the protrusion and covers the pressure relief hole.

9. The battery cell as recited in claim 1 wherein the pressure relief member is located on a side of the first wall remote from the insulating member, and the protective member is attached to the protective tab.

10. The battery cell as recited in claim 1, wherein the protection member is attached to a side surface of the connector facing the first wall.

11. The battery cell as recited in claim 10, wherein the protective member is adhered to the first wall by a gel.

12. The battery cell as recited in claim 10 wherein a weakened portion is provided on the connector, the weakened portion being provided around at least a portion of an edge of the protector.

13. The battery cell as recited in claim 1, wherein the connector comprises a polycarbonate substrate, a polypropylene substrate, or a polyethylene terephthalate substrate.

14. The battery cell as recited in claim 1, wherein the protective member is made of a high temperature resistant and heat insulating material.

15. The battery cell as recited in claim 14 wherein the protective member comprises one of glass fiber, mica, ceramic, and ceramic rubber.

16. The battery cell of claim 1, wherein the first wall is an end cap that covers the opening of the housing.

17. The cell defined in claim 1, wherein the cell includes an electrical core assembly housed within the housing.

18. A battery comprising a cell according to any one of claims 1 to 17.

19. An electric device comprising an electric main body and the battery cell according to any one of claims 1 to 17.