CN216903145U - Battery monomer, battery and consumer - Google Patents

Abstract

The application relates to a single battery, a battery and electric equipment, and belongs to the technical field of battery manufacturing. The battery cell includes: a housing having an opening; the end cover is arranged at the opening, and the peripheral part of the end cover is welded with the inner wall of the shell; and a bent part is formed at the end part of the shell close to the opening, and the bent part covers the welding part of the end cover and the shell. The battery monomer has high safety.

Description

Battery cells, batteries and electrical equipment

technical field

The present application relates to the technical field of battery manufacturing, and in particular, to a battery cell, a battery and an electrical device.

Background technique

Energy saving and emission reduction is the key to the sustainable development of the automobile industry. Electric vehicles have become an important part of the sustainable development of the automobile industry due to their advantages of energy saving and environmental protection. For electric vehicles, battery technology is an important factor in its development.

In the development of battery technology, in addition to improving the energy density of the battery, the safety of the battery is a problem that cannot be ignored. Therefore, how to improve the safety of the battery is a technical problem that needs to be solved urgently in the battery technology.

Utility model content

The purpose of this application is to provide a battery cell, a battery and an electrical device. The battery cell has high safety.

This application is achieved through the following technical solutions:

In a first aspect, the present application provides a battery cell, including:

a housing, having an opening;

an end cover, disposed at the opening, and the outer periphery of the end cover is welded with the inner wall of the casing;

Wherein, a bent portion is formed on the end portion of the casing close to the opening, and the bent portion covers the welding portion of the end cover and the casing.

According to the battery cell of the embodiment of the present application, the end of the case close to the opening is bent to form a bent portion, and the bent portion covers the welding part of the end cover and the case, so that the bent portion can be used for the connection between the end cover and the case. The welding part is shielded to reduce the probability of rusting of the welding part between the end cover and the shell, and improve the safety and service life of the battery cell.

According to some embodiments of the present application, the bent portion is in sealing engagement with the end cap.

In the above solution, a blocking area can be formed between the bent portion and the end cap through the sealing cooperation of the bent portion and the end cap, so as to isolate the welding portion and the outside of the end cap and the shell, and avoid the end cap and the shell. The welding part is exposed, which can effectively prevent the welding part of the end cover and the shell from rusting, reduce the probability of rusting of the welding part of the end cover and the shell, and further improve the safety and service life of the battery cell.

According to some embodiments of the present application, the battery cell further includes: an electrode assembly disposed in the casing, and a first tab is formed at one end of the electrode assembly close to the end cap; a current collecting member disposed on Between the electrode assembly and the end cap, the current collecting member is used for connecting the first tab and the end cap.

In the above solution, the first tab and the end cap are connected through the current collecting member, so that the end cap can conduct the electrical energy of the electrode assembly.

According to some embodiments of the present application, the end cap and the current collecting member are welded, and the bent portion covers the welding portion of the end cap and the current collecting member.

In the above solution, the welding part of the end cap and the current collecting member is covered by the bending part, so that the welding part of the end cap and the current collecting member is shielded, and the probability of rusting of the welding part of the end cap and the current collecting member is reduced, and further Extend battery life.

According to some embodiments of the present application, a surface of the end cap facing away from the current collecting member is provided with a concave portion, and the concave portion is used for accommodating the bent portion.

In the above solution, the end cap is provided with a concave portion, and the bent portion is accommodated in the concave portion, which can realize the storage of the bent portion, protect the bent portion, and the appearance of the battery cell is beautiful.

According to some embodiments of the present application, the bent portion is parallel to the end cap.

In the above solution, the bent portion is arranged in parallel with the end cap, so that the bent portion occupies less space and can reduce the overall size of the battery cell.

According to some embodiments of the present application, the bent portion does not extend beyond the surface of the end cap facing away from the current collecting member.

In the above solution, the bent portion does not exceed the surface of the end cap that faces away from the current collecting member, so that the bent portion is completely accommodated in the concave portion. Under the condition of ensuring the strength of the end cap, the storage of the bent portion is realized, and the battery cells are stored. of compact structure.

According to some embodiments of the present application, a boss is formed on a side of the end cap away from the current collecting member, and an end of the bent portion is hooked on the boss.

In the above solution, the bending part is hooked on the boss, that is, the bending part is fastened to the boss, so as to ensure the mechanical properties of the bending part and increase the connection strength between the end cover and the shell.

According to some embodiments of the present application, the casing is provided with a notch for bending an end of the casing close to the opening along the notch to form the bent portion.

In the above solution, the arrangement of the notch facilitates the bending of the end of the casing near the opening along the notch, which reduces the difficulty of bending the casing and reduces the impact of casing bending on the welding part of the casing and the end cover. At the same time, the notch can ensure that the bending position is fixed, and the length of the bending part is fixed, so as to ensure the consistency of the battery cell assembly process.

In a second aspect, the present application provides a battery including the battery cell according to any one of the above solutions.

In a third aspect, the present application provides an electrical device comprising the battery according to any one of the above solutions, the battery is used to provide electrical energy.

The above description is only an overview of the technical solution of the present application. In order to be able to understand the technical means of the present application more clearly, it can be implemented according to the content of the description, and in order to make the above-mentioned and other purposes, features and advantages of the present application more obvious and easy to understand , and the specific embodiments of the present application are listed below.

Description of drawings

In order to illustrate the technical solutions of the embodiments of the present application more clearly, the following drawings will briefly introduce the drawings that need to be used in the embodiments. It should be understood that the following drawings only show some embodiments of the present application, and therefore do not It should be regarded as a limitation of the scope, and for those of ordinary skill in the art, other related drawings can also be obtained according to these drawings without any creative effort.

1 is a schematic structural diagram of a vehicle provided according to some embodiments of the present application;

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

3 is a cross-sectional view of a battery cell provided according to some embodiments of the present application;

FIG. 4 is a partial schematic diagram of a battery cell provided according to some embodiments of the present application;

FIG. 5 is a partial enlarged view of the assembled state of the housing and the end cover provided according to some embodiments of the present application;

FIG. 6 is a partial enlarged view of the assembled state of the housing and the end cover provided according to other embodiments of the present application;

FIG. 7 is a partial schematic diagram of the assembled state of the housing and the end cover provided according to further embodiments of the present application;

FIG. 8 is a partial schematic diagram of a battery cell provided according to other embodiments of the present application;

FIG. 9 is a partial schematic diagram of the assembled state of the bending portion and the boss of the end cap provided according to some embodiments of the present application;

10 is a schematic diagram of a dent of an end cap provided according to some embodiments of the present application;

Fig. 11 is a partial schematic diagram of the assembled state of the bending portion and the boss of the end cap provided according to other embodiments of the present application;

FIG. 12 is a partial schematic diagram of a battery cell provided according to further embodiments of the present application.

Icon: 100-battery; 101-case; 1011-first part; 1012-second part; 10-battery cell; 11-end cap; 111-accommodating cavity; 115-dent; 116-sink; 12-shell; 121-opening; 122-bending; 123-scoring; 13-electrode assembly; 14-current collecting member; 15-sealing layer; 16-sealing ring; 17-electrode terminal; 200-controller; 300-motor; 1000-vehicle.

Detailed ways

The embodiments of the present application will be described in further detail below with reference to the accompanying drawings and examples. The following detailed description of the embodiments and the accompanying drawings are used to illustrate the principles of the present application by way of example, but should not be used to limit the scope of the present application, that is, the present application is not limited to the described embodiments.

Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the technical field of this application; the terms used herein are for the purpose of describing specific embodiments only, and are not intended to be Limiting this application; the terms "comprising" and "having" and any variations thereof in the specification 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 the present application, the technical terms "first", "second", etc. are only used to distinguish different objects, and should not be understood as indicating or implying relative importance or implying the number, specificity and quantity of indicated technical features. Sequential or primary and secondary relationships. In the description of the embodiments of the present application, "plurality" means two or more, unless otherwise expressly and specifically defined.

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 the phrase in various places in the specification are not necessarily all referring to the same embodiment, nor a separate or alternative embodiment that is mutually exclusive of other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

In the description of the embodiments of the present application, the term "and/or" is only an association relationship for describing associated objects, indicating that there may be three relationships, such as A and/or B, which may indicate that A exists alone, and A exists at the same time and B, there are three cases of B alone. In addition, the character "/" in this document generally indicates that the related objects are an "or" relationship.

In the description of the embodiments of the present application, the term "plurality" refers to two or more (including two), similarly, "multiple groups" refers to more than two groups (including two groups), and "multiple sheets" refers to is more than two pieces (including two pieces).

In the description of the embodiments of the present application, the technical terms "center", "longitudinal", "horizontal", "length", "width", "thickness", "top", "bottom", "front", "rear", "left", "right", "vertical" "Horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. indicate the orientation or positional relationship 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, rather than indicating or implying that the indicated device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as implementing the present application. example limitations.

In the description of the embodiments of the present application, unless otherwise expressly specified and limited, the technical terms "installation", "connection", "connection", "fixed" and other terms should be understood in a broad sense, for example, it may be a fixed connection or a fixed connection. The connection can be disassembled 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, and it can be the internal communication between the two elements or the interaction relationship between the two elements. Those of ordinary skill in the art can understand the specific meanings of the above terms in the embodiments of the present application according to specific situations.

In this application, reference to a battery refers to a single physical module comprising one or more battery cells to provide higher voltage and capacity. For example, the batteries mentioned in this application may include battery modules or battery packs, and the like.

The battery cell includes an electrode assembly and an electrolyte, and the electrode assembly is composed of a positive pole piece, a negative pole piece and a separator. The battery cell mainly relies on the movement of metal ions between the positive pole piece and the negative pole piece to work. The positive electrode sheet includes a positive electrode current collector and a positive electrode active material layer, the positive electrode active material layer is coated on the surface of the positive electrode current collector, and the positive electrode current collector without the positive electrode active material layer protrudes from the positive electrode collector coated with the positive electrode active material layer. The fluid, the positive electrode current collector without the positive electrode active material layer was used as the positive electrode tab. Taking a lithium-ion battery as an example, the material of the positive electrode current collector can be aluminum, and the positive electrode active material can be lithium cobalt oxide, lithium iron phosphate, ternary lithium, or lithium manganate. The negative electrode pole piece includes a negative electrode current collector and a negative electrode active material layer, the negative electrode active material layer is coated on the surface of the negative electrode current collector, and the negative electrode current collector without the negative electrode active material layer is protruded from the negative electrode collector that has been coated with the negative electrode active material layer. Fluid, the negative electrode current collector without the negative electrode active material layer is used as the negative electrode tab. The material of the negative electrode current collector can be copper, and the negative electrode active material can be carbon or silicon. In order to ensure that a large current is passed without fusing, the number of positive tabs is multiple and stacked together, and the number of negative tabs is multiple and stacked together. The material of the separator can be PP (polypropylene, polypropylene) or PE (polyethylene, polyethylene), and the like.

The battery cell includes a casing and an end cover. The casing has an opening so that the electrode assembly can be placed inside the casing. The end cover is arranged at the opening of the casing and is connected with the casing to form a closed space. The end cover and the inner wall of the shell can be connected by welding.

The development of battery technology needs to consider many design factors at the same time, such as performance parameters such as discharge capacity, charge-discharge rate, and energy density. In addition, safety needs to be considered.

For battery cells, there are many factors that affect the safety, such as excessive charging current, ambient temperature, corrosion of connection parts, etc. The inventors have found that the welding part between the end cap and the inner wall of the casing is prone to rust. The reason for the corrosion of the welding part is that the casing and the end cap are both metal parts. During the assembly process of the battery cell, due to the welding operation The protective coating (such as nickel coating) of the shell is damaged, which makes the rust prevention effect of the welding part poor. Because the welding part between the end cover and the inner wall of the shell is exposed, during use, when a large current is input/output, a large amount of The moisture generated by the heat and subsequent air cooling adheres to the surface of the welding part, which in turn causes the welding part to oxidize and rust, increase the contact resistance, cause poor electrical contact, and even cause the electrolyte inside the battery cell to leak, affecting the battery. security.

In view of this, in order to solve the problem of corrosion of the welding part between the end cap and the inner wall of the case during the use of the battery cell, the inventor has designed a battery cell through in-depth research, by folding the end of the case close to the opening Bend to form a bending part, cover the welding part of the end cover and the shell, so that the bending part can block the welding part of the end cover and the shell, and reduce the probability of rusting of the welding part of the end cover and the shell .

In such a battery cell, since the bent part covers the welding part of the end cap and the casing, the welding part of the end cap and the casing is protected from being polluted by the outside world, and the welding part is prevented from oxidizing and rusting, which can effectively Reduce the probability of rusting of the welded part.

With the use of the battery cell, the shielding effect formed by the bending part effectively reduces the probability of corrosion of the welding part between the end cap and the shell, and improves the safety and service life of the battery cell.

The battery cells disclosed in the embodiments of the present application may be used, but not limited to, in electrical equipment such as vehicles, ships, or aircraft. A power supply system including the battery cells and batteries disclosed in the present application can be used to form the electrical equipment, which is beneficial to improve the safety and service life of the battery cells.

In the present application, the battery cells may include lithium-ion secondary batteries, lithium-ion primary batteries, lithium-sulfur batteries, sodium-lithium-ion batteries, sodium-ion batteries, or magnesium-ion batteries, etc., which are not limited in the embodiments of the present application.

The embodiment of the present application provides an electrical device using a battery as a power source. The electrical device can be, but is not limited to, a mobile phone, a tablet computer, a notebook computer, an electric toy, an electric tool, an electric bicycle, an electric motorcycle, an electric vehicle, a ship, spacecraft, etc. The electric toys may include stationary or mobile electric toys, such as game consoles, electric car toys, electric ship toys, electric airplane toys, etc., and spacecraft may include airplanes, rockets, space shuttles, and spaceships.

In the following embodiments, for the convenience of description, a vehicle according to an embodiment of the present application is used as an example for description.

Please refer to FIG. 1 , which is a schematic structural diagram of a vehicle 1000 according to some embodiments of the present application. The vehicle 1000 may be a fuel vehicle, a gas vehicle, or a new energy vehicle, and the new energy vehicle may be a pure electric vehicle, a hybrid vehicle, or an extended-range vehicle. The interior of the vehicle 1000 is provided with the battery 100 , and the battery 100 may be provided at the bottom or the head or the rear of the vehicle 1000 . The battery 100 can be used for power supply of the vehicle 1000 , for example, the battery 100 can be used as the operating power source of the vehicle 1000 , for the circuit system of the vehicle 1000 , such as for starting, navigating and running of the vehicle 1000 .

The vehicle 1000 may also include a controller 200 and a motor 300 for controlling the battery 100 to supply power to the motor 300 , eg, for starting, navigating, and running the vehicle 1000 for work power requirements.

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

Please refer to FIG. 2 , which is a schematic diagram of an exploded structure of a battery 100 provided according to some embodiments of the present application. The battery 100 includes a case 101 and a battery cell 10 , and the battery cell 10 is accommodated in the case 101 . Among them, the box body 101 is used to provide accommodation space for the battery cells 10 , and the box body 101 can adopt various structures. In some embodiments, the case 101 may include a first part 1011 and a second part 1012 , the first part 1011 and the second part 1012 are covered with each other, and the first part 1011 and the second part 1012 together define a space for accommodating the battery cells 10 accommodating space. The second part 1012 can be a hollow structure with one end open, the first part 1011 can be a plate-like structure, and the first part 1011 is covered with the open side of the second part 1012, so that the first part 1011 and the second part 1012 together define an accommodating space The first part 1011 and the second part 1012 can also be hollow structures with one side open, and the opening side of the first part 1011 is covered with the opening side of the second part 1012 . Of course, the box body 101 formed by the first part 1011 and the second part 1012 may have various shapes, such as a cylinder, a rectangular parallelepiped, and the like.

In the battery 100 , there may be a plurality of battery cells 10 , and the plurality of battery cells 10 may be connected in series or in parallel or in a mixed connection. A mixed connection means that the plurality of battery cells 10 are both connected in series and in parallel. The plurality of battery cells 10 can be directly connected in series or in parallel or mixed together, and then the whole composed of the plurality of battery cells 10 is accommodated in the box 101 ; of course, the battery 100 can also be a plurality of battery cells 10 The battery 100 modules are first connected in series or in parallel or mixed to form a battery 100 module, and multiple battery 100 modules are then connected in series or in parallel or mixed to form a whole, and are accommodated in the box 101 . The battery 100 may further include other structures, for example, the battery 100 may further include a bus component for realizing electrical connection between the plurality of battery cells 10 .

Wherein, each battery cell 10 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.

Please refer to FIGS. 3 and 4 , FIG. 3 is a cross-sectional view of a battery cell 10 provided according to some embodiments of the present application, FIG. 4 is a partial schematic diagram of the battery cell 10 provided according to some embodiments of the present application, and FIG. 4 is a diagram of Enlarged view of point A of 3. The battery cell 10 refers to the smallest unit constituting the battery 100 . As shown in FIGS. 3 and 4 , the battery cell 10 includes an end cap 11 , a case 12 , an electrode assembly 13 and a current collecting member 14 .

The end cap 11 refers to a component that covers the opening 121 of the casing 12 to isolate the internal environment of the battery cell 10 from the external environment. Without limitation, the shape of the end cap 11 may be adapted to the shape of the housing 12 to fit the housing 12 . In some embodiments, the end cap 11 can be made of a material with certain hardness and strength (such as steel), so that the end cap 11 is not easily deformed when it is squeezed and collided, so that the battery cell 10 can have higher The structural strength and safety performance can also be improved. The end cap 11 may be provided with a pressure relief mechanism for releasing the internal pressure when the internal pressure or temperature of the battery cell 10 reaches a threshold value. In some embodiments, the material of the end cap 11 may be a metal piece, such as steel, copper, iron, aluminum, and the like. Optionally, the material of the end cap 11 may be steel.

The housing 12 is an assembly used to cooperate with the end cap 11 to form an internal environment of the battery cell 10, wherein the formed internal environment can be used to accommodate the electrode assembly 13, the electrolyte, and other components. The casing 12 and the end cap 11 can be independent parts, and an opening 121 can be provided on the casing 12 , and the end cap 11 can cover the opening 121 at the opening 121 to form the internal environment of the battery cell 10 . The shape of the casing 12 can be determined according to the specific shape and size of the electrode assembly 13 . The housing 12 can be made of various materials, such as copper, iron, aluminum, steel, aluminum alloy, plastic, and the like. Optionally, in the embodiment of the present application, the material of the casing 12 is steel as an example for introduction.

The electrode assembly 13 is a part in which an electrochemical reaction occurs in the battery cell 10 . One or more electrode assemblies 13 may be contained within the housing 12 . The electrode assembly 13 is mainly formed by winding or stacking a positive electrode and a negative electrode, and a separator is usually provided between the positive electrode and the negative electrode. The body of the electrode assembly 13 includes a part of the positive electrode and the negative electrode with active material and a separator, and the positive electrode and the part of the negative electrode without an active material respectively constitute tabs. The positive electrode tab and the negative electrode tab can be located at one end of the body together or at two ends of the body respectively.

Please refer to FIG. 5 , which is further combined with FIG. 3 and FIG. 4 , FIG. 5 is a partial enlarged view of the housing 12 and the end cap 11 in an assembled state according to some embodiments of the present application, and FIG. 5 is the position B of FIG. 4 . Enlarge the image. According to some embodiments of the present application, the present application provides a battery cell 10 , as shown in FIGS. 3 to 5 , the battery cell 10 includes a casing 12 and an end cap 11 . The housing 12 has an opening 121 . The end cover 11 is disposed at the opening 121 , and the outer peripheral portion of the end cover 11 is welded to the inner wall of the housing 12 . A bent portion 122 is formed at the end of the casing 12 close to the opening 121 , and the bent portion 122 covers the welding portion of the end cover 11 and the casing 12 .

The case 12 in the embodiment of the present application is cylindrical, and the battery cell 10 is a cylindrical battery cell 10 .

The opening 121 of the casing 12 is used for the electrode assembly 13 to be placed inside the casing 12 ; the end cap 11 is disposed at the opening 121 , and the outer periphery of the end cap 11 is welded with the inner wall of the casing 12 to close the opening 121 .

The end cap 11 has two opposite surfaces along its thickness direction, and the outer peripheral portion of the end cap 11 is the part connecting the two opposite surfaces in the thickness direction of the end cap 11 , that is, the circumference of the end cap 11 around its central axis. noodle. The outer peripheral portion of the end cover 11 and the inner wall of the casing 12 have a large contact area, and the outer peripheral portion of the end cover 11 is welded with the inner wall of the casing 12 to seal the opening 121 of the casing 12 .

The bent part 122 is a part formed by bending the end of the casing 12 close to the opening 121 , and the bent part 122 is bent toward the central axis of the casing 12 ; the bent part 122 covers the welding between the end cover 11 and the casing 12 In other words, in a plane perpendicular to the central axis of the casing 12 , the projection of the bent portion 122 covers the welding position of the end cap 11 and the casing 12 .

Taking the material of the casing 12 as steel as an example, the casing 12 includes a steel layer and a coating applied to the surface of the steel layer. When the casing 12 and the end cover 11 are welded, the coating of the casing 12 is easily damaged and the steel layer is exposed. . When the welding part of the end cover 11 and the casing 12 is exposed, the welding part is in contact with moisture, and is easily oxidized and rusted, and further rust occurs at the welding part.

According to the battery cell 10 of the embodiment of the present application, the bent portion 122 is formed by bending the end portion of the case 12 close to the opening 121 , and the bent portion 122 covers the welding portion of the end cap 11 and the case 12 , so that the bent portion 122 can shield the welding part of the end cap 11 and the shell 12 from being polluted by the outside world, prevent the welding part from oxidizing and rusting, effectively reduce the probability of rusting of the welding part, and improve the safety and use of the battery cell 10 life.

According to some embodiments of the present application, optionally, the bent portion 122 is in sealing engagement with the end cap 11 .

Please refer to FIG. 5 and FIG. 6 , FIG. 6 is a partial enlarged view of the assembled state of the housing 12 and the end cover 11 provided according to other embodiments of the present application, and FIG. 6 is an enlarged view of part B of FIG. 4 . There are many ways for the bending portion 122 to be sealed with the end cap 11 . For example, as shown in FIG. 5 , a sealant is applied between the bending portion 122 and the end cap 11 , or, as shown in FIG. 6 , the bending portion 122 A sealing ring 16 is arranged between the end cap 11 .

In the embodiment in which the sealant is applied between the bent portion 122 and the end cap 11, as shown in FIG. A ring of sealing layer 15 is formed to fill the gap between the bent portion 122 and the end cover 11 , and to isolate the welding part of the end cover 11 and the shell 12 from the outside. Optionally, the sealant is a conductive adhesive to realize the electrical connection between the end cap 11 and the housing 12 .

In the embodiment in which the sealing ring 16 is provided between the bent portion 122 and the end cover 11, as shown in FIG. Press against the sealing ring 16 , so as to realize the sealing cooperation between the bent portion 122 and the end cover 11 . The sealing ring 16 has a certain elasticity. In the initial state, the sealing ring 16 protrudes out of the accommodating cavity 111 . When the bending part 122 presses against the sealing ring 16 , the sealing ring 16 is deformed under pressure, and the sealing ring 16 and the bending part 122 are pressed and deformed. The contact area between them increases, so that the gap between the bent portion 122 and the end cover 11 is sealed by the sealing ring 16 , which isolates the welding part of the end cover 11 and the housing 12 from the outside.

Through the sealing cooperation between the bent portion 122 and the end cap 11, a blocking area can be formed between the bent portion 122 and the end cap 11, so as to isolate the welding part of the end cap 11 and the shell 12 from the outside and avoid the end cap 11 and the shell. The welding part of the body 12 is exposed, which effectively prevents the welding part of the end cover 11 and the shell 12 from rusting, reduces the probability of rusting of the welding part of the end cover 11 and the shell 12, and further improves the safety and service life of the battery cell 10. .

According to some embodiments of the present application, optionally, as shown in FIGS. 3 and 4 , the battery cell 10 further includes an electrode assembly 13 and a current collecting member 14 . The electrode assembly 13 is disposed in the casing 12 , and a first tab is formed at one end of the electrode assembly 13 close to the end cap 11 . The current collecting member 14 is disposed between the electrode assembly 13 and the end cap 11 , and the current collecting member 14 is used for connecting the first tab and the end cap 11 .

The electrode assembly 13 is a part in which an electrochemical reaction occurs in the battery cell 10 . The first tab is the electrical energy lead-out area of the electrode assembly 13 . The electrode assembly 13 further includes second tabs, which may be located at opposite ends of the electrode assembly 13 from the first tabs, and are used for electrical connection with the electrode terminals 17 of the battery cells 10 .

The first tab can be a negative tab, the second tab can be a positive tab, the electrode terminal 17 is insulated from the casing 12 , the casing 12 is negatively charged, and the electrode terminal 17 is positively charged.

The current collecting member 14 is a component that realizes the electrical connection between the electrode assembly 13 and the end cap 11 , the first tab is connected to the current collecting member 14 , and conducts electrical energy to the end cap 11 through the current collecting member 14 .

The first tab and the end cap 11 are connected through the current collecting member 14 , so that the end cap 11 can conduct the electric energy of the electrode assembly 13 out.

The current collecting member 14 is located between the electrode assembly 13 and the end cap 11 , and the first tab can be welded with the current collecting member 14 to ensure the connection strength between the first tab and the current collecting member 14 .

According to some embodiments of the present application, optionally, the end cap 11 and the current collecting member 14 are welded, and the bent portion 122 covers the welding portion of the end cap 11 and the current collecting member 14 .

The end cap 11 and the current collecting member 14 are welded to ensure the connection strength between the end cap 11 and the current collecting member 14 and prevent the current collecting member 14 from moving relative to the end cap 11 .

The welding method of the end cap 11 and the current collecting member 14 is that the end cap 11 and the current collecting member 14 are welded together along the thickness direction of the end cap 11 , so the welding marks of the end cap 11 and the current collecting member 14 appear on the end cap 11 . The side facing away from the current collecting member 14 . When the welding part of the end cap 11 and the current collecting member 14 is exposed, the welding part of the end cap 11 and the current collecting member 14 is easily oxidized and rusted, and then rust occurs. The fact that the bent portion 122 covers the welding portion of the end cap 11 and the current collecting member 14 means that in a plane perpendicular to the central axis of the housing 12 , the projection of the bent portion 122 covers the welding portion of the end cap 11 and the current collecting member 14 . projection.

It should be noted that the extending direction of the central axis of the housing 12 is parallel to the thickness direction of the end cover 11 .

In the embodiment in which the bent portion 122 is sealed with the end cap 11, the sealing portion of the bent portion 122 and the end cap 11 is close to the end of the bent portion 122, and the welding portion and the end of the end cap 11 and the housing 12 are closed. Both the welding portion of the cover 11 and the current collecting member 14 are isolated from the outside. For example, in the embodiment in which the sealing ring 16 is provided between the bent portion 122 and the end cover 11, as shown in FIG. The welding part with the current collecting member 14 is arranged in the accommodating cavity 111 of the end cover 11 for accommodating the sealing ring 16 . When the welding part of the end cover 11 and the current collecting member 14 is arranged in the accommodating cavity 111 , the thickness of the end cover 11 in the region of the accommodating cavity 111 is small, which facilitates the welding operation of the end cover 11 and the current collecting member 14 . Alternatively, in the embodiment in which sealant is applied between the bent portion 122 and the end cap 11, as shown in FIG. 5, the sealant connects the bent portion 122 and the end cap 11, and the sealing layer 15 may cover the end cap 11 and the end cap 11. Welding site of the flow member 14 .

By covering the welding part of the end cap 11 and the current collecting member 14 by the bending part 122, the welding part of the end cap 11 and the current collecting member 14 can be shielded, so as not to be polluted by the outside world, preventing oxidation and rusting, and reducing the connection between the end cap 11 and the collecting member 14. The probability of rusting at the welded part of the flow member 14 further prolongs the service life of the battery cell 10 .

Please refer to FIG. 7 , FIG. 7 is a partial schematic view of the assembled state of the housing 12 and the end cap 11 according to further embodiments of the present application, and FIG. 7 is an enlarged view of FIG. 4 . According to some embodiments of the present application, optionally, as shown in FIG. 7 , a surface of the end cap 11 facing away from the current collecting member 14 is provided with a concave portion 112 , and the concave portion 112 is used to accommodate the bent portion 122 .

The surface of the end cap 11 facing away from the current collecting member 14 refers to the surface of the end cap 11 facing away from the current collecting member 14 in the thickness direction, that is, the surface of the end cap 11 away from the current collecting member 14 . This surface and the surface of the end cap 11 for connection with the current collecting member 14 are disposed opposite to each other in the thickness direction of the end cap 11 . The current collecting member 14 and the bent portion 122 are located on both sides in the thickness direction of the end cover 11 .

The concave portion 112 is provided on the surface of the end cap 11 away from the current collecting member 14 and is concave toward the current collecting member 14, thereby forming a concave space on the side of the end cap 11 away from the current collecting member 14, and the concave portion 112 is used for accommodating The bent portion 122 , after the end of the casing 12 close to the opening 121 is bent to form the bent portion 122 , the bent portion 122 is accommodated in the recessed portion 112 .

The bending portion 122 may be entirely accommodated in the concave portion 112 , or may be partially accommodated in the concave portion 112 , and the other portion may protrude from the concave portion 112 .

The end cap 11 is provided with a recessed portion 112, and the bent portion 122 is accommodated in the recessed portion 112, so that the bent portion 122 can be accommodated, the bent portion 122 can be protected, and the battery cell 10 has a beautiful appearance.

According to some embodiments of the present application, optionally, the bent portion 122 is parallel to the end cap 11 .

The bent portion 122 is formed after the casing 12 is bent, and the bent portion 122 is parallel to the end cap 11 means that the surface of the bent portion 122 facing away from the current collecting member 14 is parallel to the end cap 11 .

The bent portion 122 is disposed in parallel with the end cap 11 , so that the bent portion 122 occupies less space and can reduce the overall size of the battery cell 10 .

According to some embodiments of the present application, optionally, the bent portion 122 does not extend beyond the surface of the end cap 11 facing away from the current collecting member 14 .

The fact that the bent portion 122 does not exceed the surface of the end cap 11 that faces away from the current collecting member 14 means that, along the thickness direction of the end cap 11 , the bent portion 122 does not exceed the surface of the end cap 11 that faces away from the current collecting member 14 , that is, the bent portion 122 does not exceed the surface of the end cap 11 that faces away from the current collecting member 14 . The bent portion 122 is integrally located in the recessed portion 112, and the surface of the bent portion 122 facing away from the current collecting member 14 is flush with the surface of the end cap 11 facing away from the current collecting member 14, or, the surface of the bent portion 122 facing away from the current collecting member 14 is flush. The surface is proximate to the current collecting member 14 relative to the surface of the end cap 11 that faces away from the current collecting member 14 .

The bent portion 122 does not extend beyond the surface of the end cap 11 away from the current collecting member 14, so that the bent portion 122 is completely accommodated in the recessed portion 112, and under the condition of ensuring the strength of the end cap 11, the storage of the bent portion 122 is realized, The structure of the battery cell 10 is compact.

Please refer to FIGS. 8 and 9 , FIG. 8 is a partial schematic diagram of a battery cell 10 provided according to some embodiments of the present application, and FIG. 8 is an enlarged view of part A of FIG. 3 , and FIG. 9 is a schematic diagram of a battery cell 10 provided according to some embodiments of the present application. A partial schematic view of the bent portion 122 of the assembling state with the boss 113 of the end cap 11 , and FIG. 9 is an enlarged view of C in FIG. 8 . According to some embodiments of the present application, optionally, as shown in FIGS. 8 and 9 , a boss 113 is formed on the side of the end cover 11 away from the current collecting member 14 , and the end of the bent portion 122 is hooked to the boss 113 . Desk 113.

The boss 113 is arranged around the central axis of the end cover 11 , the central axis of the end cover 11 is collinear with the central axis of the housing 12 , and the boss 113 is an annular structure.

The end of the bent portion 122 is hooked to the boss 113 , and the bent portion 122 is bent at the boss 113 so that the end of the bent portion 122 is fastened to the side surface of the boss 113 . On the side of the end cap 11 facing away from the current collecting member 14, the surface of the end cap 11 facing away from the current collecting member 14 is concave toward the current collecting member 14 to form a concave area 114, and the unconcave portion forms the boss 113, in other words, The area enclosed by the boss 113 is the concave area 114 of the end cap 11 . The bent portion 122 covers the surface of the boss 113 away from the current collecting member 14 , and the end of the bent portion 122 extends into the recessed area 114 and is fastened to the boss 113 .

The bent portion 122 is hooked on the boss 113 , that is, the bent portion 122 is fastened to the boss 113 , so as to ensure the mechanical properties of the bent portion 122 and increase the connection strength between the end cap 11 and the housing 12 .

The end cap 11 is provided with a pressure relief mechanism at a position corresponding to the above-mentioned recessed area 114 , so that when the internal pressure or temperature of the battery cell 10 reaches a threshold value, the pressure relief mechanism releases the pressure. Please refer to FIG. 10 . FIG. 10 is a schematic diagram of the dent 115 of the end cap 11 provided according to some embodiments of the present application, and FIG. 10 is an enlarged view of D in FIG. 8 . Indentations 115 on the surface of the cover 11 . For example, the dents 115 may be carved on the surface of the end cap 11 facing the current collecting member 14 to avoid exposure of the dents 115 to the air and reduce the leakage of electrolyte caused by the corrosion of the end cap 11 .

Please refer to FIG. 11 . FIG. 11 is a partial schematic view of the assembled state of the bending portion 122 and the boss 113 of the end cap 11 according to other embodiments of the present application, and FIG. 11 is an enlarged view of C in FIG. 8 . In order to facilitate the welding of the end cap 11 and the current collecting member 14 , as shown in FIG. 11 , the area of the boss 113 close to the outer periphery of the end cap 11 sinks toward the current collecting member 14 to form a sinking area 116 where the end cap 11 is located. The thickness of the sunken area 116 is relatively small, and the sunken area 116 is the welding area of the end cap 11 and the current collecting member 14 , in other words, the welding part of the end cap 11 and the current collecting member 14 is located in the sunken area 116 . A sealing ring 16 may be provided in the sinking area 116, the bending part 122 is pressed against the sealing ring 16, and the sealing ring 16 forms a support for the bending part 122 to prevent the bending part 122 from sinking to the sinking area 116; at the same time, the sealing ring 16 can protect the welding part of the end cover 11 and the current collecting member 14 .

Please refer to FIG. 12 . FIG. 12 is a partial schematic view of a battery cell 10 provided according to further embodiments of the present application, and FIG. 12 shows a notch 123 of the case 12 . According to some embodiments of the present application, optionally, the casing 12 is provided with a notch 123 for bending an end of the casing 12 close to the opening 121 along the notch 123 to form a bent portion 122 .

The notch 123 is a trace engraved on the casing 12 , that is, an area formed by a depression on the surface of the casing 12 , and the thickness of the casing 12 at the notch 123 is thinner than that of other areas, so that the casing 12 is The difficulty of bending at the notch 123 is reduced, which facilitates the bending of the casing 12 .

In order to ensure the strength of the casing 12 , the depth of the notch 123 should not be too large. If the depth of the notch 123 is too large, it is easy to cause the casing 12 to break at the notch 123 when the casing 12 is bent; the depth of the notch 123 should not be too small. , the depth of the notch 123 is too small, making it difficult to bend the casing 12 .

Optionally, the depth of the notch 123 may be 1/3˜2/3 of the wall thickness of the housing 12 .

When the shell 12 is bent, the force on the bending place of the shell 12 will cause the shell 12 to deform, and the shell 12 deforms to transmit the stress. When the stress is transmitted to the welding part of the end cover 11 and the shell 12, The connection strength between the end cap 11 and the housing 12 will be affected. The setting of the notch 123 facilitates the bending of the end of the casing 12 near the opening 121 along the notch 123, which reduces the difficulty of bending the casing 12 and reduces the impact of the casing 12 on the casing 12 and the end cover 11. At the same time, the notch 123 can ensure that the bending position is fixed, and the length L of the bending portion 122 is fixed, so as to ensure the consistency of the assembly process of the battery cell 10 . In the figure, the dimension shown by the letter L is the length of the bent portion 122 .

It should be pointed out that the length L of the bent portion 122 refers to the distance from the end of the bent portion 122 to the notch 123 , that is, before the shell 12 is bent, along the direction of the central axis of the shell 12 , the shell The distance from the end of 12 near the opening 121 to the notch 123.

According to some embodiments of the present application, the present application provides a battery 100 . The battery 100 includes the battery cell 10 as described in any of the above aspects.

According to some embodiments of the present application, the present application provides an electrical device. The electrical equipment includes the battery 100 described in any of the above solutions, and the battery 100 is used to provide electrical energy for the electrical equipment.

According to some embodiments of the present application, as shown in FIGS. 3 and 5 , the present application provides a cylindrical battery cell 10 , including a casing 12 , an end cap 11 , an electrode assembly 13 and a current collecting member 14 . The housing 12 has an opening 121 . The electrode assembly 13 is provided inside the case 12 . The current collecting member 14 is disposed inside the housing 12 , and the current collecting member 14 is connected to the first tab of the electrode assembly 13 and the end cap 11 to realize electrical connection between the first tab and the end cap 11 . The end cap 11 is disposed at the opening 121 , and the outer peripheral portion of the end cap 11 is welded with the inner wall of the housing 12 to close the opening 121 . A bent portion 122 is formed at the end of the casing 12 near the opening 121 .

By covering the welding part of the end cap 11 and the casing 12 and the welding part of the end cap 11 and the current collecting member 14 by the bending part 122, the welding part of the end cap 11 and the casing 12 and the welding part of the end cap 11 and the current collecting member 14 are realized. The shielding of the welding part can avoid external pollution, prevent oxidation and rust, effectively reduce the probability of rusting of the welding part, and improve the safety and service life of the battery cell 10.

Although the application has been described with reference to the preferred embodiments, various modifications may be made and equivalents may be substituted for parts thereof without departing from the scope of the application. In particular, as long as there is no structural conflict, each technical feature mentioned in each embodiment can be combined in any manner. The present application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims (11)

1. A battery cell, characterized in that, comprising: a housing, having an opening; an end cover, disposed at the opening, and the outer periphery of the end cover is welded with the inner wall of the casing; Wherein, a bent portion is formed on the end portion of the housing close to the opening, and the bent portion covers the welding portion of the end cover and the housing. 2 . The battery cell according to claim 1 , wherein the bent portion is in sealing fit with the end cap. 3 . 3. The battery cell according to claim 1, wherein the battery cell further comprises: an electrode assembly, disposed in the casing, and a first tab is formed at one end of the electrode assembly close to the end cover; A current collecting member is disposed between the electrode assembly and the end cap, and the current collecting member is used for connecting the first tab and the end cap. 4 . The battery cell according to claim 3 , wherein the end cap and the current collecting member are welded, and the bent portion covers the welding portion of the end cap and the current collecting member. 5 . 5 . The battery cell according to claim 3 , wherein a surface of the end cap facing away from the current collecting member is provided with a concave portion, and the concave portion is used for accommodating the bent portion. 6 . 6 . The battery cell according to claim 5 , wherein the bent portion is parallel to the end cap. 7 . 7 . The battery cell according to claim 6 , wherein the bent portion does not extend beyond a surface of the end cap facing away from the current collecting member. 8 . 8 . The battery cell according to claim 3 , wherein a boss is formed on a side of the end cap away from the current collecting member, and an end of the bent portion is hooked on the boss. 9 . . 9 . The battery cell according to claim 1 , wherein the casing is provided with a notch, so that an end of the casing close to the opening is bent along the notch to form a notch. 10 . the bending part. 10. A battery, characterized by comprising the battery cell according to any one of claims 1-9. 11. An electrical device, characterized by comprising the battery according to claim 10, which is used to provide electrical energy.

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