CN217788569U - Battery cell, battery and power consumption device - Google Patents

Abstract

The application provides a battery monomer, battery and power consumption device, battery monomer includes: the electrode assembly comprises an electrode main body and a lug extending from the end face of the electrode main body, wherein the electrode main body comprises a pole piece and a diaphragm which are arranged in a laminated manner; the infiltration film comprises a first end and a second end which are oppositely arranged in the length direction of the infiltration film, the second end is connected with the diaphragm, and the first end extends out of the end face. In the technical scheme of this application embodiment, the electrolyte that flows out the electrode main part can flow back to in the electrode main part once more through soaking the membrane for at least part electrolyte that flows out the electrode main part can be utilized once more, and then improves the utilization ratio of electrolyte.

Description

Battery cell, battery and power consumption device

Technical Field

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

Background

Energy conservation and emission reduction are the key points of sustainable development of the automobile industry, and electric vehicles become important components of the sustainable development of the automobile industry due to the advantages of energy conservation and environmental protection. For electric vehicles, battery technology is an important factor in its development.

In the process of transporting or using the conventional battery, the electrolyte in the battery may overflow from the inside of the electrode assembly into the shell of the battery cell, so that the electrolyte cannot be fully utilized.

Disclosure of Invention

In view of the above problems, the present application provides a battery cell, a battery, and an electric device, which can improve the utilization rate of an electrolyte.

In a first aspect, the present application provides a battery cell, comprising: the electrode assembly comprises an electrode main body, wherein the electrode main body comprises a pole piece and a diaphragm which are arranged in a stacked mode; an end cap disposed at one side of the electrode assembly; and the infiltration film comprises a first end and a second end which are oppositely arranged in the length direction of the infiltration film, the second end is connected with the diaphragm, and the first end extends towards the end cover and extends out of the electrode main body.

In the technical scheme of the embodiment of the application, the battery monomer comprises an electrode assembly, an end cover and a soaking film, the electrode assembly comprises an electrode main body, the electrode main body comprises a pole piece and a diaphragm, and electrolyte is soaked in the diaphragm. The first end of the infiltration film is connected with the diaphragm, and the second end of the infiltration film extends towards the end cover and extends out of the electrode main body. When the battery cell is inverted or laid during transportation or use, the electrolyte may flow out from the electrode main body. The second end of the infiltration film extends out of the electrode main body and can absorb part of electrolyte, and the first end of the infiltration film is connected with the diaphragm, so that the electrolyte on the infiltration film can flow to the diaphragm. Therefore, the electrolyte flowing out of the electrode main body can flow back into the electrode main body again through the wetting film, so that at least part of the electrolyte flowing out of the electrode main body can be reused, and the utilization rate of the electrolyte is further improved.

In some embodiments, the electrode assembly further comprises a tab extending from the end face of the electrode body toward the end cap, and the wetting film is attached to the surface of the tab. The wetting film is attached to the lug instead of being suspended in the shell of the single battery, so that on one hand, the stability of the position of the wetting film can be improved, and the use effect of the wetting film is improved due to the fact that the wetting film is broken caused by shaking in the single battery. On the other hand, the infiltration film can also provide protection for the tabs, and the service life of the tabs is prolonged.

In some embodiments, the tab comprises a first surface and a second surface which are oppositely arranged along the thickness direction of the tab, and the at least part of the wetting film is attached to the first surface and/or the second surface. Such that the wetting film can provide protection to the first surface and/or the second surface.

In some embodiments, the tab comprises a gathering section and a connecting section connected to one side of the gathering section, which is away from the electrode main body, and the wetting film is attached to at least part of the gathering section. So that the impregnating film is able to protect at least the gathered sections. The gathering section protrudes out of the electrode main body, and the infiltration film is attached to the gathering section and can absorb electrolyte on the peripheral side of the gathering section.

In some embodiments, the first end is connected to the gathering section, or the first end is connected to the connecting section, and the infiltration film is attached to the gathering section and the connecting section. The wetting film can be always attached to the gathering section and can extend out of the electrode main body to absorb electrolyte flowing out of the electrode main body.

In some embodiments, the connecting section further comprises an interposer connected to the first surface of the connecting section, at least a part of the wetting film is attached to the first surface, and the second end is connected to a surface of the interposer facing away from the connecting section.

In the embodiments, when the single battery is inverted, the surface of the adapter sheet departing from the connecting section is at the lowest position, and the second end of the wetting film is located on the surface of the adapter sheet departing from the connecting section, so that the wetting film can absorb the electrolyte at the lowest position through the second end, and the wetting film can transfer more electrolyte to the diaphragm, thereby improving the use effect of the wetting film. In addition, the second end of the infiltration film is positioned on the surface of the adapter sheet departing from the connecting section, so that at least part of the infiltration film can cover the surface of the adapter sheet departing from the connecting section, and the protection can be provided for the adapter sheet.

In some embodiments, the interposer includes a first section, a second section and a third section sequentially distributed along the length direction of the interposer, the second section is connected with the connecting section, the wetting film is connected with the first section, or the wetting film extends from the first section to the second section, or the wetting film extends from the first section to the third section.

In these embodiments, interconnecting the wetting film to the first section can provide protection to the first section. The wetting film is connected with the second sub-part, so that protection can be provided for the second sub-part, and when the second sub-part and the connecting section of the lug are welded with each other, short circuit connection caused by the fact that particles generated in welding cannot fall into the shell of the battery cell can be improved. The wet film is attached to each of the first, second and third sections to provide sufficient protection to the interposer.

In some embodiments, at least a portion of the wetting film is attached to the second surface, and the second end extends to a side of the connecting section facing away from the gathering section. The wetting film can be completely attached to the connecting section, and can improve short-circuit connection caused by particles generated in welding not falling into the shell of the single battery, so that the safety performance of the single battery is improved. In addition, the distribution area of the infiltration film can be increased, and the use effect of the infiltration film can be improved.

In some embodiments, the apparatus further comprises an insulating film, and the wetting film is stacked with the first end and the second end both extending beyond the insulating film. Through setting up the isolation membrane, can provide the protection to soaking the membrane, can also make in addition soak the membrane and adhere to the electrode main part through isolation membrane better. The first end and the second end of the infiltration membrane extend out of the isolation membrane, so that the second end is not affected to infiltrate and adsorb the electrolyte, and the flow of the electrolyte between the first end and the diaphragm is not affected.

In some embodiments, the number of the isolation films is more than two, and the wetting film is located between two adjacent isolation films. The two sides of the soaking film are provided with the isolation films, so that the protection effect of the isolation films can be improved, and the service life of the soaking film is prolonged.

In some embodiments, the first end and/or the second end extends beyond the insulating membrane by a dimension in the length direction of 1mm to 5mm. When the size of the first end and/or the second end extending out of the isolation membrane is within the range, the problem that the soaking membrane absorbs or releases electrolyte due to the fact that the size of the first end and/or the second end extending out of the isolation membrane is too short can be solved, and the problem that the protection force of the isolation membrane is insufficient due to the fact that the size of the first end and/or the second end extending out of the isolation membrane is too long can be solved.

In some embodiments, the width of the wetting film is greater than or equal to the width of the insulating film along the width direction of the wetting film, the width direction being perpendicular to the length direction. The side end face of the wetting film or the wetting film can be exposed out of the isolation film, and the using effect of the wetting film is improved.

In some embodiments, the width of the wetting film is greater than the width of the isolation film, and the wetting film extends beyond the isolation film in the width direction. The side face of the infiltration film in the width direction can absorb electrolyte, and the using effect of the infiltration film can be improved.

In some embodiments, the size of the wetting film that protrudes beyond the insulating film in the width direction is 1mm to 5mm. When the size of the wetting film extending out of the isolation film is within the range, the problem that the wetting film absorbs or releases electrolyte due to the fact that the size of the wetting film extending out of the isolation film is too small can be solved, and the problem that the protection strength of the isolation film is insufficient due to the fact that the size of the wetting film extending out of the isolation film is too long can be solved.

In some embodiments, the material of the barrier film comprises polyethylene terephthalate. The insulating film has good structural strength and sealing performance, and the protective performance of the insulating film can be improved.

In some embodiments, the electrode body includes an end face for attachment of a tab, the second end being attached to the end face, the second end being attachable to the separator exposed at the end face.

In some embodiments, the electrode body includes an end surface for connecting the tab, the electrode body further includes a side surface connected to the periphery of the end surface and extending in a direction away from the tab, and the second end is connected to the side surface. The second end can be connected with the diaphragm exposed from the side face, the contact area of the second end and the diaphragm can be increased, and electrolyte can better flow to the diaphragm from the wetting film.

In some embodiments, the electrode body includes an end surface for attachment of the tab, the electrode body further including a bottom surface disposed opposite the end surface, the second end being attached to the bottom surface. The second end is capable of attaching the septum exposed by the bottom surface.

In some embodiments, the material of the wetting film comprises at least one of polypropylene, polyethylene. The infiltration film has good infiltration capacity and can better absorb electrolyte.

In some embodiments, the wetting film has a film thickness of 5 μm to 60 μm. When the thickness of the wetting film is within the range, the influence of too small thickness of the wetting film on the wetting capability of the wetting film can be improved, and the influence of too large thickness of the wetting film on the energy density of the single battery can also be improved.

In a second aspect, an embodiment of the present application further provides a battery, including any one of the battery cells of the first aspect.

In a third aspect, an embodiment of the present application further provides an electric device, including any one of the batteries in the second aspect, where the battery is used to provide electric energy.

The foregoing description is only an overview of the technical solutions of the present application, and the present application can be implemented according to the content of the description in order to make the technical means of the present application more clearly understood, and the following detailed description of the present application is given in order to make the above and other objects, features, and advantages of the present application more clearly understandable.

Drawings

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

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

fig. 2 is a schematic structural diagram of a battery pack according to an embodiment of the present application;

fig. 3 is a schematic structural diagram of a battery module according to an embodiment of the present disclosure;

fig. 4 is an exploded view of a battery cell according to an embodiment of the present disclosure;

fig. 5 is a schematic cross-sectional view of an electrode assembly in the battery cell of fig. 4;

fig. 6 is a schematic diagram of a partial enlarged structure of a battery cell according to an embodiment of the present disclosure;

fig. 7 is a diagram illustrating a positional relationship between a wetting film and an isolation film of a single battery according to an embodiment of the present disclosure.

The reference numbers in the detailed description are as follows:

1 vehicle, 10 battery, 11 controller, 12 motor;

20 a battery module;

30 boxes, 301 first box parts; 302 a second tank portion;

100 battery cells, 110 end caps, 111 electrode terminals, 120 casings, 130 electrode assemblies, 131 electrode bodies, 131a end faces, 131b side faces, 131c bottom faces, 132 tabs, 132a first surfaces, 132b second surfaces, 132c converging sections, 132d transition sections, 132e connecting sections, HS welding areas, 133 pole pieces, 133a positive pole pieces, 133b negative pole pieces, 134 separators, 140 wetting films, 141 first ends, 142 second ends, 150 adapter pieces, 151 first subsections, 152 second subsections, 153 third subsections, 160 isolation films.

Detailed Description

Embodiments of the present invention will be described in detail below with reference to the accompanying drawings. The following examples are only used to illustrate the technical solutions of the present application more clearly, and therefore are only used as examples, and the protection scope of the present application is not limited thereby.

It should be noted that technical terms or scientific terms used in the embodiments of the present application should be understood as having a common meaning as understood by those skilled in the art to which the embodiments of the present application belong, unless otherwise specified.

In the description of the embodiments of the present application, 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 indicate orientations or positional relationships that are based on the orientations or positional relationships shown in the drawings, merely for convenience of description and simplified description, and do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore should not be construed as limiting the embodiments of the present application.

Furthermore, the technical terms "first", "second", etc. 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. In the description of the embodiments of the present application, "a plurality" means two or more unless specifically defined otherwise.

In the description of the embodiments of the present application, unless otherwise explicitly specified or limited, the terms "mounted," "connected," "fixed," and the like are to be construed broadly, e.g., as meaning fixedly connected, detachably connected, or integrally formed; mechanical connection or electrical connection is also possible; they may be directly connected or indirectly connected through intervening media, or may be connected through the use of two elements or the interaction of two elements. The specific meanings of the above terms in the embodiments of the present application can be understood by those of ordinary skill in the art according to specific situations.

In the description of the embodiments of the present application, unless otherwise explicitly specified or limited, a first feature "on" or "under" a second feature may be directly contacting the first and second features, or the first and second features may be indirectly contacting each other 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.

At present, the application of the power battery is more and more extensive from the development of market situation. 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, electric automobiles and the like, 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 expanding.

In this application, the battery cell may include a lithium ion secondary battery cell, a lithium ion primary battery cell, a lithium sulfur battery cell, a sodium lithium ion battery cell, a sodium ion battery cell, or a magnesium ion battery cell, and the embodiment of the present application is not limited thereto. The battery cell may be a cylinder, a flat body, a rectangular parallelepiped, or other shapes, which is not limited in the embodiments of the present application.

Reference to a battery in embodiments of the present application refers to a single physical module that includes one or more battery cells to provide higher voltage and capacity. For example, the battery referred to in the present application may include a battery module or a battery pack, etc. Batteries generally include a case for enclosing one or more battery cells. The box can avoid liquid or other foreign matters to influence the charge or discharge of battery cells.

The battery cell comprises an electrode assembly and electrolyte, wherein the electrode assembly comprises a positive pole piece, a negative pole piece and a separator. The battery cell mainly depends on metal ions to move between the positive pole piece and the negative pole piece to work. The positive pole piece comprises a positive current collector and a positive active substance layer, and the positive active substance layer is coated on the surface of the positive current collector; the positive electrode current collector comprises a positive electrode current collecting part and a positive electrode lug connected to the positive electrode current collecting part, wherein the positive electrode current collecting part is coated with a positive electrode active substance layer, and the positive electrode lug is not coated with the positive electrode active substance layer. Taking a lithium ion battery as an example, the material of the positive electrode current collector may be aluminum, the positive electrode active material layer includes a positive electrode active material, and the positive electrode active material may be lithium cobaltate, lithium iron phosphate, ternary lithium, lithium manganate, or the like. The negative pole piece comprises a negative pole current collector and a negative pole active substance layer, and the negative pole active substance layer is coated on the surface of the negative pole current collector; the negative current collector comprises a negative current collecting part and a negative electrode lug connected to the negative current collecting part, wherein the negative current collecting part is coated with a negative active material layer, and the negative electrode lug is not coated with the negative active material layer. The material of the negative electrode current collector may be copper, the negative electrode active material layer includes a negative electrode active material, and the negative electrode active material may be carbon, silicon, or the like. The material of the spacer may be PP (polypropylene) or PE (polyethylene).

The present inventors have noted that the battery cell includes an electrode main body and a tab extending from the electrode main body. The electrolyte is typically impregnated within the body of the electrode. During the transportation or use process of the battery monomer, the battery monomer can be inverted, namely, the tab of the battery monomer is positioned below the electrode main body; or the battery cells may be in a lateral arrangement, i.e., the tabs of the battery cells are located on one side of the electrode body in the horizontal direction. This may cause the electrolyte to flow out of the electrode main body, and a part of the electrolyte flowing out of the electrode main body may not be sufficiently used.

In order to alleviate the problem of insufficient utilization rate of the electrolyte, the applicant researches and discovers that when the battery cell is inverted in the battery box body, a component capable of absorbing the electrolyte can be arranged in the battery cell, the component extends out of the electrode main body and points to the bottom of the battery box body, so that the component can absorb the electrolyte outside the electrode main body and transfer the absorbed electrolyte into the electrode main body again.

Based on the above consideration, the inventors have conducted intensive studies to design a battery cell, a battery, and an electric device in order to solve the problem of insufficient utilization of an electrolyte.

In such a battery cell, the battery cell includes an electrode assembly including an electrode main body including a pole piece and a separator, and a tab extending from the electrode main body, and a wetting film. One end of the infiltration film extends out of the electrode main body and is used for absorbing electrolyte outside the electrode main body, and the other end of the infiltration film is connected with the diaphragm and is used for transferring the electrolyte into the electrode main body.

The technical scheme described in the embodiment of the application is suitable for the battery and the electric device using the battery.

The electric device can be a vehicle, a mobile phone, a portable device, a notebook computer, a ship, a spacecraft, an electric toy, an electric tool and the like. The vehicle can be a fuel oil vehicle, a gas vehicle or a new energy vehicle, and the new energy vehicle can be a pure electric vehicle, a hybrid electric vehicle or a range extending vehicle and the like; spacecraft include aircraft, rockets, space shuttles, spacecraft, and the like; the electric toys include stationary or mobile electric toys, such as game machines, electric car toys, electric ship toys, electric airplane toys, and the like; the electric power tools include metal cutting electric power tools, grinding electric power tools, assembly electric power tools, and electric power tools for railways, such as electric drills, electric grinders, electric wrenches, electric screwdrivers, electric hammers, electric impact drills, concrete vibrators, and electric planers. The embodiment of the present application does not specifically limit the above power utilization device.

It should be understood that the technical solutions described in the embodiments of the present application are not limited to be applied to the above described batteries and electric devices, but may be applied to all batteries including a box and electric devices using batteries.

Referring to fig. 1, fig. 1 is a schematic structural diagram of a vehicle 1 according to some embodiments of the present disclosure. The vehicle 1 can be a fuel automobile, a gas automobile or a new energy automobile, and the new energy automobile can be a pure electric automobile, a hybrid electric automobile or a range-extended automobile and the like. The interior of the vehicle 1 is provided with a battery 10, and the battery 10 may be provided at the bottom or at the head or tail of the vehicle 1. The battery 10 may be used for power supply of the vehicle 1, and for example, the battery 10 may serve as an operation power source of the vehicle 1. The vehicle 1 may further include a controller 11 and a motor 12, the controller 11 being configured to control the battery 10 to power the motor 12, for example, for start-up, navigation, and operational power requirements while the vehicle 1 is traveling.

In some embodiments of the present application, the battery 10 may be used not only as an operating power source of the vehicle 1, but also as a driving power source of the vehicle 1, instead of or in part of fuel or natural gas, to provide driving power for the vehicle 1.

In order to meet different power requirements, the battery 10 may include a plurality of battery cells, which are the smallest units constituting a battery module or a battery pack. A plurality of battery cells may be connected in series and/or in parallel via electrode terminals to be applied to various applications. The battery referred to in this application includes a battery module or a battery pack. The plurality of battery cells can be connected in series or in parallel or in series-parallel, and the series-parallel refers to the mixture of series connection and parallel connection. In the embodiment of the application, a plurality of battery cells may directly form a battery pack, or may first form the battery module 20, and then the battery module 20 forms the battery pack.

Fig. 2 shows a schematic structural diagram of the battery 10 according to an embodiment of the present application.

As shown in fig. 2, the battery includes a case 30 and a battery cell (not shown) accommodated in the case.

The box body 30 may be a single cuboid, a cylinder, a sphere, or other simple three-dimensional structure, or may be a complex three-dimensional structure formed by combining cuboid, cylinder, or sphere, which is not limited in the embodiment of the present application. The material of the box 30 may be an alloy material such as an aluminum alloy and an iron alloy, a polymer material such as polycarbonate and polyisocyanurate foam, or a composite material such as glass fiber and epoxy resin, which is not limited in the embodiment of the present application.

The case body is used to accommodate the battery cells, and the case body 30 may have various structures. In some embodiments, the case may include a first case portion 301 and a second case portion 302, the first case portion 301 and the second case portion 302 cover each other, and the first case portion 301 and the second case portion 302 together define a receiving space for receiving the battery cell. The second casing portion 302 may be a hollow structure with one open end, the first casing portion 301 is a plate-shaped structure, and the first casing portion 301 covers the open end of the second casing portion 302 to form a casing with an accommodating space. The first tank portion 301 and the second tank portion 302 may be hollow structures with one side open, and the open side of the first tank portion 301 covers the open side of the second tank portion 302 to form the tank 30 with the accommodating space. Of course, the first tank portion 301 and the second tank portion 302 may be various shapes, such as a cylinder, a rectangular parallelepiped, and the like.

In order to improve the sealing property after the first tank portion 301 and the second tank portion 302 are connected, a sealing member, such as a sealant or a gasket, may be provided between the first tank portion 301 and the second tank portion 302.

Assuming that the first box portion 301 covers the top of the second box portion 302, the first box portion 301 may also be referred to as an upper box cover, and the second box portion 302 may also be referred to as a lower box body.

In the battery, there may be one or more battery cells. If the number of the battery monomers is multiple, the multiple battery monomers can be connected in series or in parallel or in series-parallel, and the series-parallel refers to that the multiple battery monomers are connected in series or in parallel. The plurality of battery monomers can be directly connected in series or in parallel or in series-parallel, and the whole formed by the plurality of battery monomers is accommodated in the box body 30; of course, a plurality of battery cells may be connected in series, in parallel, or in series-parallel to form the battery module 20, and a plurality of battery modules 20 may be connected in series, in parallel, or in series-parallel to form a whole and be accommodated in the box 30.

Fig. 3 shows a schematic structural diagram of the battery module 20 according to an embodiment of the present application.

In some embodiments, as shown in fig. 3, the battery unit 100 is a plurality of battery units 100, and the plurality of battery units 100 are connected in series or in parallel or in series-parallel to form the battery module 20. The plurality of battery modules 20 are connected in series or in parallel or in series-parallel to form a whole, and are accommodated in the case.

The plurality of battery cells 100 in the battery module 20 may be electrically connected to each other by a bus member, so as to connect the plurality of battery cells in the battery module 20 in parallel, in series, or in series-parallel.

In this application, the battery cell 100 may include a lithium ion battery cell, a sodium ion battery cell, a magnesium ion battery cell, or the like, which is not limited in this application. The battery cell 100 may be a cylinder, a flat body, a rectangular parallelepiped, or other shapes, which is not limited in the embodiments of the present application. The battery cells 100 are generally divided into three types in a packaging manner: the cylindrical battery monomer, the square battery monomer and the soft package battery monomer are not limited in the embodiment of the application. However, for the sake of simplicity, the following embodiments are all described by taking a square battery cell as an example.

Fig. 4 is an exploded schematic view of a battery cell 100 according to some embodiments of the present disclosure. Fig. 5 is a schematic cross-sectional view of the electrode assembly of fig. 4. Fig. 6 is a partially enlarged schematic structural diagram of the battery cell 100 according to some embodiments of the present disclosure. The battery cell 21 refers to the smallest unit constituting the battery.

As shown in fig. 4 to 6, the battery cell 100 includes an electrode assembly 130, an end cap 110, and a wetting film 140. The electrode assembly 130 includes an electrode body 131, the electrode body 131 including a pole piece 133 and a separator 134 which are stacked; the end cap 110 is disposed at one side of the electrode assembly 130; the wetting film 140 includes a first end 141 and a second end 142 opposite to each other in a length direction thereof, the second end 142 is connected to the separator 134, and the first end 141 extends toward the end cap 110 and protrudes from the electrode main body 131.

The electrode assembly 130 is a component of the battery cell 100 in which electrochemical reactions occur. The electrode assembly 130 includes an electrode body 131 and tabs 132 provided at end surfaces 131a of the electrode body 131. The tab 133 includes a positive tab 133a and a negative tab 133b, the tab 132 includes a positive tab 132 and a negative tab 132, the electrode assembly 130 is mainly formed by winding or stacking the positive tab 133a and the negative tab 133b, and a separator 134 is generally disposed between the positive tab 133a and the negative tab 133 b. The separator 134 is used to ensure the mutual insulation of the positive electrode sheet 133a and the negative electrode sheet 133b, and the separator 134 is used to soak the electrolyte. The portions of the positive and negative electrode tabs 133a and 133b having the active material constitute the electrode body 131 of the electrode assembly 130, and the portions of the positive and negative electrode tabs 133a and 133b having no active material each constitute the tab 132. The positive and negative electrode tabs 132 and 132 may be co-located at one end of the electrode body 131 or separately located at both ends of the electrode body 131. During the charge and discharge of the battery, the positive and negative active materials react with the electrolyte, and the tab 132 is connected to the electrode terminal 111 to form a current loop.

The battery cell 100 further includes a case 120, and the end cap 110 refers to a member covering an opening of the case 120 to isolate the internal environment of the battery cell 100 from the external environment. Without limitation, the shape of the end cap 110 may be adapted to the shape of the housing 120 to fit the housing 120. Alternatively, the end cap 110 may be made of a material (e.g., an aluminum alloy) having a certain hardness and strength, so that the end cap 110 is not easily deformed when being extruded and collided, and the battery cell 100 may have a higher structural strength and improved safety performance. The end cap 110 may be provided with functional components such as electrode terminals 111. The electrode terminal 111 may be used to be electrically connected with the electrode assembly 130 for outputting or inputting electric energy of the battery cell 100. In some embodiments, a pressure relief mechanism for relieving the internal pressure when the internal pressure or temperature of the battery cell 100 reaches a threshold value may be further disposed on the end cap 110. The material of the end cap 110 may be various materials, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., and the embodiment of the present invention is not limited thereto. In some embodiments, insulation may also be provided on the inside of the end cap 110, which may be used to isolate the electrical connection components within the housing 120 from the end cap 110 to reduce the risk of short circuits. Illustratively, the insulator may be plastic, rubber, or the like.

The wetting film 140 is capable of wetting at least a portion of the electrolyte, i.e., the electrolyte is capable of being absorbed by the wetting film 140. The first end 141 of the wetting film 140 extends out of the end face 131a, and the second end 142 is connected to the diaphragm 134, so that the wetting film 140 can transfer the electrode solution outside the electrode body 131 to the diaphragm 134.

In the technical solution of the embodiment of the present application, the battery cell 100 includes an electrode assembly 130, an end cap 110 and a separator, the electrode assembly 130 includes an electrode main body 131, the electrode main body 131 includes a pole piece 133 and a separator 134, and the separator 134 is impregnated with an electrolyte. The first end 141 of the wetting film 140 is connected to the diaphragm 134, and the second end 142 of the wetting film 140 extends toward the end cap 110 and out of the electrode body 131. When the battery cell 100 is inverted or laid during transportation or use, the electrolyte may flow out of the electrode main body 131. The second end 142 of the wetting film 140 extends out of the electrode body 131 to absorb a part of the electrolyte, and the first end 141 of the wetting film 140 is connected to the diaphragm 134, so that the electrolyte on the wetting film 140 can flow to the diaphragm 134. Therefore, the electrolyte flowing out of the electrode body 131 can flow back into the electrode body 131 through the wetting film 140, so that at least part of the electrolyte flowing out of the electrode body 131 can be reused, thereby improving the utilization rate of the electrolyte.

Alternatively, as shown in fig. 5 and 6, the separator 134 may be located on the side surface 131b of the electrode main body 131, or the separator 134 may be exposed from the end surface 131a and the bottom surface 131c of the electrode main body 131. There are a variety of ways in which the second end 142 is attached to the diaphragm 134, and the second end 142 can be interconnected with the diaphragm 134 in at least one of the end face 131a, the side face 131b, and the bottom face.

Optionally, with continued reference to fig. 4, the battery cell 100 further includes a housing 120.

The case 120 is an assembly for fitting the end cap 110 to form an internal environment of the battery cell 100, wherein the formed internal environment may be used to house the electrode assembly 130, an electrolyte (not shown in the drawings), and other components. The housing 120 and the end cap 110 may be separate components, and an opening may be formed in the housing 120, and the opening may be covered by the end cap 110 to form the internal environment of the battery cell 100. Without limitation, the end cap 110 and the housing 120 may be integrated, and specifically, the end cap 110 and the housing 120 may form a common connecting surface before other components are inserted into the housing, and when it is required to enclose the inside of the housing 120, the end cap 110 covers the housing 120. The housing 120 may be various shapes and various sizes, such as a rectangular parallelepiped, a cylindrical shape, a hexagonal prism shape, and the like. Specifically, the shape of the case 120 may be determined according to the specific shape and size of the electrode assembly 130. The material of the housing 120 may be various, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., and the embodiment of the present invention is not limited thereto.

According to some embodiments of the present application, as shown in fig. 6, the electrode assembly 130 further includes a tab 132 extending from the electrode body 131 toward the end cap 110, and the wetting film 140 is attached to the surface of the tab 132. Alternatively, the wetting film 140 may be bonded to the surface of the tab 132 by using an adhesive or a bonding layer.

In these optional embodiments, the wetting film 140 is attached to the tab 132 instead of being suspended in the housing of the battery cell 100, which can improve the position stability of the wetting film 140 on the one hand, and improve the effect of the wetting film 140 on the use due to the breakage of the wetting film 140 caused by shaking in the battery cell 100. On the other hand, the wetting film 140 can also provide protection for the tab 132, and improve the service life of the tab 132.

In some embodiments, as shown in fig. 6, the tab 132 includes a first surface 132a and a second surface 132b oppositely disposed along the thickness direction thereof, and at least a portion of the wetting film 140 is attached to the first surface 132a and/or the second surface 132b. Such that the wetting film 140 can provide protection to the first surface 132a and/or the second surface 132b. For example, when the tab 132 includes a plurality of lamination sheets arranged in a stack, the thickness direction is the stacking direction of the lamination sheets.

Generally, when the tab 132 and the interposer 150 are connected to each other, the tab 132 is bent to form a dog-ear. One of the first surface 132a and the second surface 132b is an outer surface of the tab 132 facing away from the break angle, and the other is an inner surface forming the break angle. The embodiment of the present application is illustrated with the first surface 132a as the outer surface and the second surface 132b as the inner surface.

When at least part of the wetting film 140 is attached to the first surface 132a, the wetting film 140 can provide protection for the tab 132, and the risk that the tab 132 is deformed by external parts is improved. When at least part of the wetting film 140 is attached to the second surface 132b, for example, when the wetting film 140 is attached to the bending position, the wetting film 140 can improve the tab 132 insertion caused by the tab 132 bending, and can improve the service life of the tab 132.

In some embodiments, as shown in fig. 6, the tab 132 includes a gathered section 132c and a connecting section 132e connected to a side of the gathered section 132c facing away from the electrode body 131, and the wetting film 140 is attached to at least a portion of the gathered section 132c.

Optionally, the tab 132 further includes a transition section 132d connected between the gathering section 132c and the connection section 132e, the tab fragments gather together in the gathering section 132c, and are bent in the transition section 132, and the connection section 132e is used for connecting the adaptor fragment.

In these embodiments, the tab 132 is bent at the transition section 132d to form a bevel, and the tab 132 is welded to the interposer 150 at the connection section 132 e. When the wetting film 140 is attached to at least a portion of the gathered section 132c, the wetting film 140 can at least protect the gathered section 132c. The gathering section 132c protrudes from the electrode main body 131, and the wetting film 140 is attached to the gathering section 132c and can absorb the electrolyte around the gathering section 132c.

Optionally, the first end 141 is attached to the gathered segment 132c such that the saturating film 140 can cover at least a portion of the gathered segment 132c.

Or, the first end 141 is connected to the transition section 132d, and the wetting film 140 can be attached to the converging section 132c and at least part of the transition section 132d, so that the wetting film 140 can provide protection for the converging section 132c and the transition section 132d at the same time, and in addition, the distribution area of the wetting film 140 outside the electrode main body 131 can be increased, and the use effect of the wetting film 140 can be improved.

Optionally, the first end 141 is connected to the connecting section 132e, and the infiltration film 140 may also be attached to the gathering section 132c, the transition section 132d, and at least a portion of the connecting section 132e, so as to further improve the protection effect and the use effect of the infiltration film 140. The effect of the wetting film 140 is the effect of the wetting film 140 transferring the electrolyte to the separator 134.

Optional connecting section 132e is flush with end face 131a to facilitate welding of interposer 150 and connecting section 132e to one another.

In some embodiments, as shown in fig. 6, the battery cell 100 further includes an interposer 150 connected to the first surface 132a of the connection segment 132e, at least a portion of the wetting film 140 is attached to the first surface 132a, and the second end 142 is connected to a surface of the interposer 150 facing away from the connection segment 132 e. The gray filled area in fig. 6 is the area where the interposer 150 and the connection section 132e are welded to each other.

In these embodiments, when the battery cell 100 is inverted, the surface of the interposer 150 facing away from the connection segment 132e is located at the lowest position, and the second end 142 of the wetting film 140 is located at the surface of the interposer 150 facing away from the connection segment 132e, so that the wetting film 140 can absorb the electrolyte at the lowest position through the second end 142, and the wetting film 140 can transfer more electrolyte to the diaphragm 134, thereby improving the use effect of the wetting film 140. In addition, the second end 142 of the wetting film 140 is located on the surface of the interposer 150 facing away from the connection section 132e, so that at least part of the wetting film 140 can cover the surface of the interposer 150 facing away from the connection section 132e, and can provide protection for the interposer 150.

In some embodiments, as shown in fig. 6, the interposer 150 includes a first sub-portion 151, a second sub-portion 152, and a third sub-portion 153 sequentially distributed in a length direction thereof, the second sub-portion 152 is connected to the connection section 132e, the wetting film 140 is connected to the first sub-portion 151, or the wetting film 140 extends from the first sub-portion 151 to the second sub-portion 152, or the wetting film 140 extends from the first sub-portion 151 to the third sub-portion 153. The second subsection 152 in fig. 6 is the part of the interposer 150 covered by the grey area, i.e. the part of the interposer 150 welded to the connection section 132 e.

In the direction from the transition section 132d to the connection section 132e, the first subsection 151 refers to the part of the transition section 132d of the tab 132 on the interposer 150, and the third subsection 153 refers to the part of the transition section 132d of the tab 150 remote from the tab 132.

In these embodiments, the interconnecting of the wetting membrane 140 and the first subsection 151 can provide protection to the first subsection 151. The wetting film 140 is connected to the second sub-portion 152 to protect the second sub-portion 152, and when the second sub-portion 152 and the connection section 132e of the tab 132 are welded to each other, short-circuit connection caused by particles generated during welding not falling into the case of the battery cell 100 can be improved. The wetting film 140 in conjunction with the first, second and third sections 151, 152, 153 provides sufficient protection to the interposer 150.

In some embodiments, as shown in fig. 6, at least a portion of the wetting film 140 is attached to the second surface 132b, and the second end 142 extends to a side of the connecting section 132e facing away from the gathering section 132c. For example, the tab 132 is provided with a welding area HS, and the second end 142 extends to a side of the welding area HS facing away from the gathering section 132c. In fig. 6, the portion of the connecting section 132e covered by the gray filling area is a welding area HS, that is, the area of the connecting section 132e where the interposer 150 is welded to each other is a welding area HS.

In these embodiments, the wetting film 140 can be completely attached to the bonding area, and the wetting film 140 can improve the short circuit connection caused by particles generated during welding that do not fall into the case of the battery cell 100, thereby improving the safety performance of the battery cell 100. In addition, the distribution area of the wetting film 140 can be increased, and the use effect of the wetting film 140 can be improved.

In some embodiments, as shown in fig. 6 and 7, the battery cell further includes an isolation film 160, the isolation film 160 and the wetting film 140 are stacked, and the first end 141 and the second end 142 both extend out of the isolation film 160. The insulating film 160 is an insulating film.

In these embodiments, by providing the isolation film 160, protection can be provided to the wetting film 140, and in addition, the wetting film 140 can be better attached to the electrode main body 131 through the isolation film 160. The first end 141 and the second end 142 of the wetting film 140 extend out of the isolation film 160, so that the wetting and the absorption of the electrolyte at the second end 142 are not affected, and the flow of the electrolyte between the first end 141 and the diaphragm 134 is not affected.

In some embodiments, the number of the isolation films 160 is two or more, and the wetting film 140 is located between two adjacent isolation films 160. By arranging the isolation films 160 on both sides of the wetting film 140, the protection effect of the isolation films 160 can be improved, and the service life of the wetting film 140 can be prolonged.

In some embodiments, as shown in fig. 6 and 7, first end 141 and/or second end 142 extend from insulating film 160 by a dimension of 1mm to 5mm in the length direction. The lengthwise direction may be the Z direction in fig. 7.

When the dimension of the first end 141 extending out of the isolation film 160 is within the above range, it is possible to improve the influence of the too short dimension of the first end 141 extending out of the isolation film 160 on the transfer speed of the electrolyte between the wetting film 140 and the diaphragm 134, and also improve the insufficient protection strength of the isolation film 160 caused by the too long dimension of the first end 141 extending out of the isolation film 160.

When the size of the second end 142 extending out of the isolation membrane 160 is within the above range, it is possible to improve the effect of the short size of the second end 142 extending out of the isolation membrane 160 on the speed of the wetting membrane 140 absorbing the electrolyte, and also improve the insufficient protection force of the isolation membrane 160 caused by the long size of the second end 142 extending out of the isolation membrane 160.

In some embodiments, as shown in fig. 6 and 7, the width of the wetting film 140 is greater than or equal to the width of the insulating film 160 in the width direction of the wetting film 140, which is perpendicular to the length direction. The width direction may be the Y direction in fig. 7.

In these embodiments, the width of the wetting film 140 is greater than or equal to the width of the isolation film 160, so that the wetting film 140 or the side end surfaces 131a of the wetting film 140 can be exposed from the isolation film 160, and further the side end surfaces 131a of the wetting film 140 can absorb or transfer the electrolyte, thereby improving the use effect of the wetting film 140.

In some embodiments, as shown in fig. 7, the width of the wetting film 140 is larger than the width of the isolation film 160, and the wetting film 140 is disposed to protrude from the isolation film 160 in the width direction. The side surface 131b of the wetting film 140 in the width direction can absorb the electrolyte, and the use effect of the wetting film 140 can be improved.

In some embodiments, as shown in fig. 7, the size of the wetting film 140 protruding from the insulating film 160 in the width direction is 1mm to 5mm.

In these embodiments, when the size of the wetting film 140 extending out of the isolation film 160 is within the above range, it is possible to improve the speed of the wetting film 140 absorbing or releasing the electrolyte, which is affected by the too small size of the wetting film 140 extending out of the isolation film 160, and also improve the insufficient protection strength of the isolation film 160, which is caused by the too long size of the wetting film 140 extending out of the isolation film 160.

In some embodiments, the material of the insulation film 160 includes polyethylene terephthalate. The insulating film 160 has good structural strength and sealing performance, and the protective performance of the insulating film 160 can be improved.

In some embodiments, the second end 142 is connected to the end face 131a, and the second end 142 can be connected to the diaphragm 134 exposed by the end face 131 a.

In some embodiments, as shown in fig. 6, the electrode body 131 further includes a side surface 131b connected to the end surface 131a on the periphery and extending in a direction away from the tab 132, and the second end 142 is connected to the side surface 131b. The second end 142 can be connected to the diaphragm 134 exposed from the side 131b, and the contact area between the second end 142 and the diaphragm 134 can be increased, so that the electrolyte can better flow from the wetting film 140 to the diaphragm 134.

In some embodiments, the electrode body 131 further includes a bottom surface 131c disposed opposite the end surface 131a, and the second end 142 is connected to the bottom surface 131c. The second end 142 can be connected to the diaphragm 134 exposed by the bottom surface 131c.

In some embodiments, the material of the wetting film 140 includes at least one of polypropylene, polyethylene. The wetting film 140 has good wetting ability and can absorb the electrolyte better.

In some embodiments, the thickness of the wetting film 140 is 5 μm to 60 μm. When the thickness of the wetting film 140 is within the above range, the influence of too small thickness of the wetting film 140 on the wetting capability of the wetting film 140 and the influence of too large thickness of the wetting film 140 on the energy density of the battery cell 100 can be improved.

According to some embodiments of the present application, there is also provided a battery including the battery cell according to any one of the above aspects.

According to some embodiments of the present application, there is also provided an electric device, including the battery according to any of the above aspects, and the battery is used for supplying electric energy to the electric device.

The powered device may be any of the aforementioned battery-powered devices or systems.

Referring to fig. 4 to 7, in an embodiment of the present invention, a battery cell 100 is provided, where the battery cell 100 includes: an electrode assembly 130 including an electrode main body 131 and a tab 132 extending from an end face 131a of the electrode main body 131, the electrode main body 131 including a pole piece 133 and a separator 134 arranged in a stacked manner; the wetting film 140 includes a first end 141 and a second end 142 opposite to each other in the length direction, the second end 142 is connected to the diaphragm 134, the first end 141 extends out of the end face 131a, and the wetting film 140 is attached to the surface of the tab 132. The single battery 100 further includes insulation films 160 stacked with the wetting film 140, the wetting film 140 is located between the two insulation films 160, the first end 141 and the second end 142 of the wetting film 140 extend out of the insulation films 160, and the wetting film 140 is attached to the surfaces of the electrode main body 131 and the tab 132 through the insulation films 160. The tab 132 includes a first surface 132a and a second surface 132b opposite to each other in the thickness direction thereof, and at least a portion of the wetting film 140 and the isolation film 160 are attached to the first surface 132a and the second surface 132b. The battery cell 100 further includes an interposer 150, the interposer 150 is connected to the first surface 132a of the connection section 132e of the tab 132, the interposer 150 includes a first sub-portion 151, a second sub-portion 152 and a third sub-portion 153 sequentially distributed in a length direction thereof, and the wetting film 140 extends from the first sub-portion 151 to the third sub-portion 153. At least a portion of the wetting film 140 is attached to the second surface 132b, and the second end 142 extends to a side of the connecting section 132e away from the transition section 132 d. The first end 141 and/or the second end 142 may extend from the insulating film 160 by a size of 1mm to 5mm. The width of the wetting film 140 is larger than the width of the isolation film 160, and the wetting film 140 is disposed to extend beyond the isolation film 160 in the width direction. The size of the wetting film 140 extending from the insulating film 160 in the width direction is 1mm to 5mm. The material of the insulation film 160 includes polyethylene terephthalate. The material of the wetting film 140 includes at least one of polypropylene and polyethylene. The thickness of the wetting film 140 is 5 μm to 60 μm.

Finally, it should be noted that: the above embodiments are only used for illustrating the technical solutions of the present application, and not for limiting the same; although the present application has been described in detail with reference to the foregoing embodiments, it should be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; these modifications and substitutions do not depart from the spirit of the embodiments of the present application, and they should be construed as being included in the scope of the claims and description of the present application. In particular, the technical features mentioned in the embodiments can be combined in any way as long as there is no structural conflict. The present application is not intended to be limited to the particular embodiments disclosed herein but is to cover all embodiments that may fall within the scope of the appended claims.

Claims (21)

1. A battery cell, comprising:

an electrode assembly including an electrode main body including a pole piece and a separator which are stacked;

an end cap disposed at one side of the electrode assembly;

and the infiltration film comprises a first end and a second end which are oppositely arranged in the length direction of the infiltration film, the second end is connected with the diaphragm, and the first end extends towards the end cover and extends out of the electrode main body.

2. The battery cell as recited in claim 1, wherein the electrode assembly further comprises a tab extending from the end face of the electrode body toward the end cap, and the wetting film is attached to a surface of the tab.

3. The battery cell as recited in claim 2, wherein the tab includes a first surface and a second surface opposite to each other in a thickness direction of the tab, and at least a portion of the wetting film is attached to the first surface and/or the second surface.

4. The battery cell as claimed in claim 3, wherein the tab comprises a gathering section and a connecting section connected to a side of the gathering section away from the electrode main body, the connecting section is used for connecting an interposer, and the wetting film is attached to at least part of the gathering section.

5. The battery cell as recited in claim 4, wherein the first end is connected to the gathered section, or the first end is connected to the connecting section, and the wetting film is attached to the gathered section and the connecting section.

6. The battery cell of claim 4, further comprising an interposer coupled to the first surface of the connection segment, wherein at least a portion of the wetting film is attached to the first surface, and wherein the second end is coupled to a surface of the interposer facing away from the connection segment.

7. The battery cell as recited in claim 6 wherein the interposer includes a first segment, a second segment and a third segment sequentially distributed along a length of the interposer, the second segment interconnecting the connecting segment, the wetting film interconnecting the first segment, or the wetting film extending from the first segment to the second segment, or the wetting film extending from the first segment to the third segment.

8. The battery cell as recited in claim 5, wherein at least a portion of the wetting film is attached to the second surface, and the second end extends to a side of the connecting segment facing away from the gathering segment.

9. The battery cell as recited in claim 1, further comprising an insulating film, wherein the wetting film and the insulating film are stacked, and wherein the first end and the second end both extend beyond the insulating film.

10. The battery cell according to claim 9, wherein the number of the insulating films is two or more, and the wetting film is located between two adjacent insulating films.

11. The battery cell according to claim 9, wherein the first end and/or the second end protrudes beyond the insulating film by a dimension of 1mm to 5mm in the length direction.

12. The battery cell as recited in claim 9, wherein the wetting film has a width greater than or equal to a width of the insulating film along a width direction of the wetting film, the width direction being perpendicular to the length direction.

13. The battery cell of claim 12, wherein the wetting film has a width greater than a width of the insulating film, and the wetting film extends beyond the insulating film in the width direction.

14. The battery cell as recited in claim 13, wherein the size of the wetting film protruding from the insulating film in the width direction is 1mm to 5mm.

15. The battery cell as recited in claim 9 wherein the material of the insulating film comprises polyethylene terephthalate.

16. The battery cell as recited in claim 1, wherein the electrode body includes end faces for attachment of tabs,

wherein the second end is connected to the end face;

or, the electrode body further comprises a side surface connected to the peripheral side of the end surface, and the second end is connected to the side surface;

or, the electrode main body further comprises a bottom surface arranged opposite to the end surface, and the second end is connected to the bottom surface.

17. The battery cell of claim 1, wherein the material of the wetting film comprises at least one of polypropylene and polyethylene.

18. The battery cell according to claim 1, wherein the wetting film has a film thickness of 5 μm to 60 μm.

19. A battery comprising a case and a battery cell according to any one of claims 1 to 18 accommodated in the case.

20. The battery of claim 19, wherein the case includes a bottom wall, and the battery cell includes an end cap disposed on a side of the battery cell adjacent to the bottom wall.

21. An electrical device comprising the battery of claim 20, wherein the battery is configured to provide electrical energy.

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