CN221201208U - Pole piece, battery monomer, battery, electric equipment and roller piece - Google Patents

Abstract

The embodiment of the application provides a pole piece, a battery cell, a battery, electric equipment and a roller, wherein the pole piece comprises a current collector, an active layer and an interlayer, the current collector is configured to collect electrons to form an electron flow, the active layer is configured to embed or release ions, the interlayer is arranged between the active layer and the current collector, the interlayer is configured to guide electrolyte to infiltrate the active layer, the interlayer comprises a plurality of interlayer bodies, and the plurality of interlayer bodies are arranged at intervals along a preset direction. According to the application, through arranging the interlayers, the infiltration of the electrolyte can be quickened, the problem of uneven infiltration of the inner side and the outer side of the pole piece is solved, the problem of poor local infiltration of the pole piece is relieved, and the multiple interlayer bodies are arranged at intervals, so that the cost can be effectively saved.

Description

Pole piece, battery monomer, battery, electric equipment and roller piece

Technical Field

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

Background

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

In the use process of charging and discharging, the problems of black spots, lithium precipitation and the like can occur in the battery, and the safety and the service life of the battery are affected.

The statements made above merely serve to provide background information related to the present disclosure and may not necessarily constitute prior art.

Disclosure of Invention

The application provides a pole piece, a battery monomer, a battery, electric equipment and a roller piece, which can relieve the problems of black spots, lithium precipitation and the like in the battery, and improve the safety and the service life of the battery.

In a first aspect, the application provides a pole piece comprising a current collector configured to collect electrons to form an electron stream, an active layer configured to intercalate or deintercalate ions, and an interlayer disposed between the active layer and the current collector, the interlayer configured to direct an electrolyte to infiltrate the active layer.

Through the interlayer, the electrolyte can be guided to infiltrate the active layer, so that the electrolyte can infiltrate into the active layer at the outer side of the active layer far away from the current collector and the inner side of the active layer near the current collector, the infiltration is faster and more sufficient, and the time required by the infiltration is effectively shortened; due to the addition of the interlayer, the two sides of the active layer can be infiltrated simultaneously, so that the infiltration effect of the inner side of the active layer is improved, the problem of uneven infiltration of the two sides of the inner side and the outer side of the pole piece is solved, and the overall uniformity of infiltration of the pole piece is improved; even if the electrolyte is affected by gravity, under the guiding action of the interlayer, the climbing rate of the electrolyte can be improved, so that the problem of poor infiltration of the upper region in the pole piece is solved, the problems of black spots, lithium precipitation and the like of the battery in the use process are reduced, and the use safety and the service life of the battery are improved.

In some embodiments, the interlayer includes a plurality of interlayer bodies arranged at intervals along the preset direction.

Compared with the scheme of arranging the whole interlayer between the current collector and the active layer, the embodiment of the application can reduce the total area of the interlayer and save the material of the interlayer by arranging the plurality of interlayer bodies which are arranged at intervals, thereby reducing the cost of the pole piece.

In some embodiments, the plurality of sandwich bodies are spaced apart along the winding direction of the pole piece.

The electrode assembly is generally vertically arranged, the plurality of interlayer bodies are arranged at intervals along the winding direction of the pole piece, and the interlayer bodies can extend along the vertical direction, so that electrolyte is guided to climb upwards along the vertical direction, the infiltration speed of the electrolyte is increased, and the infiltration effect is improved.

In some embodiments, the sandwich body extends in a vertical direction and the width of the sandwich body decreases in a bottom-up direction.

Through setting the width of intermediate layer body to reduce along the direction from bottom to top, the width of intermediate layer body bottom is great promptly, can guide more electrolyte upwards to climb, increases the distance that the electrolyte upwards climbs, alleviates the problem that upper portion region infiltration is bad in the pole piece, reduces appear black spot, lithium analysis scheduling problem in follow-up battery use, promotes the safety in utilization of battery, prolongs the life of battery.

In some embodiments, the width of the sandwich body tapers in a bottom-up direction.

The width of the interlayer body is gradually reduced along the direction from bottom to top, and a trend of uniform reduction can be formed along the direction from bottom to top, so that the climbing speed of the electrolyte is more uniform.

In some embodiments, the edges of the sandwich body extending in the vertical direction are straight or curved.

The edge of the interlayer body extending along the vertical direction is straight, so that the edge of the interlayer body is regular, and the attractive appearance and the uniformity are good.

The edge of the interlayer body extending along the vertical direction is bent, so that the flatness requirement of the edge of the interlayer body can be reduced, and the manufacturing difficulty is reduced.

In some embodiments, the sandwich body is trapezoidal, stepped, or rectangular in shape.

The shape of the interlayer body is set to be trapezoid, the width of the lower part of the interlayer body is larger, more electrolyte can be absorbed through the lower part of the interlayer body, and the requirement of climbing upwards is met; meanwhile, the width of the upper part is narrower, so that the area of the upper part of the interlayer body can be reduced, materials are saved, and the cost is saved.

The shape of the interlayer body is set to be in a step shape, so that the interlayer body is in a sectional design, and different sizes can be set according to requirements.

The shape of the interlayer body is rectangular, so that the overall shape is regular, and the attractive appearance and the uniformity are good.

In some embodiments, the active layer is arranged in a vertical direction, with the sandwich body extending from the bottom to the top of the active layer.

The interlayer body is arranged to extend from the bottom of the active layer to the top, so that the interlayer body can guide electrolyte to climb upwards from the bottom of the active layer, and the interlayer body can still be contacted with the electrolyte after the electrolyte stock is reduced.

In some embodiments, the active layers are arranged in a vertical direction, with the sandwich body extending from the bottom of the active layers to the top and to the top of the active layers.

The interlayer body is arranged to extend from the bottom of the active layer to the top and extends to the top of the active layer, so that the interlayer body can be fully distributed with the whole height of the active layer in the vertical direction, the electrolyte is guided in the whole height direction, and the infiltration effect of the active layer on the whole height is improved.

In some embodiments, the gap between adjacent two sandwich bodies is less than the maximum width of the sandwich bodies.

The gap between two adjacent interlayer bodies is set to be smaller than the maximum width of the interlayer bodies, so that the infiltration effect of the area between the two adjacent interlayer bodies can be effectively ensured, and the probability that the area in the gap cannot be infiltrated into electrolyte due to too large gap between the two adjacent interlayer bodies is reduced.

In some embodiments, the material of the interlayer is a porous material, a multichannel tubular nanomaterial, or a polymeric material having an electrolyte-philic group.

The porous material is a material with a network structure formed by mutually communicated or closed holes, such as activated carbon, silicon dioxide or aluminum oxide and the like. The material can absorb and contain more electrolyte due to the holes, and the flowing speed of the electrolyte in the material is higher.

The multichannel tubular nanomaterial is a tubular material made of nanomaterial having a plurality of channels. The material has multiple channels, can absorb and contain more electrolyte, and has higher flow speed of the electrolyte.

The polymer material with the electrolyte-philic group comprises polysulfone (Polysulfone, PSF for short) or polyethylene glycol (Polyethylene Glycol, PEG for short) and the like. The material has electrolyte-philic groups, so that the electrolyte can be attracted to be close, more electrolyte is accumulated, and the diffusion speed of the electrolyte is increased.

In some embodiments, the pole piece includes a plurality of interlayers arranged in a superimposed manner along the direction of the active layer toward the current collector.

Through the overlapping arrangement of a plurality of interlayers along the direction of the active layer pointing to the current collector, the method is equivalent to arranging a plurality of layers of interlayers between the current collector and the active layer, the total thickness and the total area of the interlayers are increased, the guiding effect of the interlayers on electrolyte is further enhanced, and the infiltration effect of the electrolyte is improved.

In a second aspect, the present application provides a battery cell, including a case and the above-mentioned electrode assembly, the electrode assembly is accommodated in the case, the electrode assembly includes a positive electrode sheet, a negative electrode sheet, and a separator disposed between the positive electrode sheet and the negative electrode sheet, and the positive electrode sheet and/or the negative electrode sheet are the above-mentioned sheets.

In a third aspect, the present application provides a battery, including the above battery cell.

In a fourth aspect, the present application provides an electric device, including the battery, where the battery is used to supply electric energy to the electric device.

In a fifth aspect, the present application provides a roller for manufacturing the pole piece, comprising a roller shaft, wherein an interlayer is coated on the peripheral surface of the roller shaft, and the roller shaft is configured to roll relative to a current collector to coat the interlayer on the current collector, so as to form the pole piece.

The roll members are the components used to manufacture the pole pieces described above. When manufacturing the pole piece, the interlayer material is coated on the peripheral surface of the roller shaft, then the roller shaft rotates relative to the current collector, the interlayer material is coated on the current collector in the rotating process of the roller shaft, thus forming the current collector with the interlayer, and finally the active material is coated on the current collector with the interlayer, thus forming the pole piece.

In some embodiments, the roller further includes a plurality of protrusions disposed on the outer circumferential surface of the roller shaft and spaced apart along the circumferential direction, and the interlayer is applied to the protrusions.

By providing a plurality of protrusions, the sandwich applied to the current collector may be made to include a plurality of sandwich bodies arranged at intervals.

The foregoing description is only an overview of the present application, and is intended to be implemented in accordance with the teachings of the present application in order that the same may be more clearly understood and to make the same and other objects, features and advantages of the present application more readily apparent.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings that are needed in the embodiments of the present application will be briefly described below, and it is obvious that the drawings described below are only some embodiments of the present application, and other drawings may be obtained according to the drawings without inventive effort for a person skilled in the art.

Fig. 1 is a schematic structural diagram of some embodiments of a powered device according to the present application.

Fig. 2 is a schematic view of the structure of some embodiments of the battery provided by the application.

Fig. 3 is a schematic structural diagram of some embodiments of a battery cell provided by the present application.

Fig. 4a is a schematic structural view of a pole piece in the related art.

Fig. 4b is a schematic diagram of a pole piece in the related art at the time of electrolyte infiltration.

Fig. 5a is a schematic structural view of some embodiments of pole pieces provided by the present application.

Fig. 5b is a schematic diagram of some embodiments of pole pieces provided by the present application when immersed in an electrolyte.

Fig. 6 is a schematic structural diagram of an interlayer in the first embodiment of the pole piece provided by the application.

Fig. 7 is a schematic structural diagram of an interlayer in a second embodiment of a pole piece according to the present application.

Fig. 8 is a schematic structural diagram of an interlayer in a third embodiment of a pole piece according to the present application.

Fig. 9 is a schematic structural view of an interlayer in a fourth embodiment of a pole piece according to the present application.

Fig. 10 is a schematic structural diagram of an interlayer in a fifth embodiment of a pole piece according to the present application.

Fig. 11 is a transverse cut of some embodiments of pole pieces provided by the present application.

Fig. 12 is a schematic illustration of the infiltration of the interlayer in the first embodiment of the pole piece provided by the present application.

Fig. 13 is a schematic illustration of the infiltration of an interlayer in a third embodiment of a pole piece according to the present application.

Fig. 14 is a schematic view of some embodiments of a roller provided by the present application.

In the drawings, the drawings are not drawn to scale.

Marking: 1000. a vehicle; 100. a battery; 200. a controller; 300. a motor; 10. a case; 101. a first cover; 102. a second cover; 20. a battery cell; 21. an electrode assembly; 22. a housing; 23. an end cap; 1. a current collector; 2. an active layer; 3. an interlayer; 31. an interlayer body; 4. a first tab; 5. a second lug; 6. a roller member; 61. a roll shaft; 62. a convex part.

Detailed Description

Embodiments of the technical scheme of the present application will be described in detail below with reference to the accompanying drawings. The following examples are only for more clearly illustrating the technical aspects of the present application, and thus are merely examples, and are not intended to limit the scope of the present application.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application; the terms "comprising" and "having" and any variations thereof in the description of the application and the claims and the description of the drawings above are intended to cover a non-exclusive inclusion.

In the description of embodiments of the present application, the technical terms "first," "second," and the like are used merely to distinguish between different objects and are not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated, a particular order or a primary or secondary relationship. Furthermore, the term "vertical" is not strictly vertical but is within the allowable error range. "parallel" is not strictly parallel but is within the tolerance of the error.

Reference herein to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment may be included in at least one embodiment of the application. The appearances of such phrases in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. Those of skill in the art will explicitly and implicitly appreciate 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 merely an association relationship describing an association object, and indicates that three relationships may exist, for example, a and/or B may indicate: a exists alone, A and B exist together, and B exists alone. In addition, the character "/" herein generally indicates that the front and rear associated objects are an "or" relationship.

In the description of embodiments of the present application, the term "plurality" refers to two or more, unless specifically defined otherwise. Similarly, "multiple sets" refers to two or more sets and "multiple sheets" refers to two or more sheets unless specifically defined otherwise.

In the description of the embodiments of the present application, the orientation or positional relationship indicated by the technical terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. are based on the orientation or positional relationship shown in the drawings, and are merely for convenience of description and simplification of the description, and do not indicate or imply that the apparatus or element referred to must have a specific orientation, be configured and operated in a specific orientation, and therefore should not be construed as limiting the embodiments of the present application.

In the description of the embodiments of the present application, unless explicitly specified and limited otherwise, the terms "mounted," "connected," "secured" and the like should be construed broadly and may be, for example, fixedly connected, detachably connected, or integrally connected; or may be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communicated with the inside of two elements or the interaction relationship of the two elements. The specific meaning of the above terms in the embodiments of the present application will be understood by those of ordinary skill in the art according to specific circumstances.

Currently, the application of power batteries is more widespread 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 various fields such as aerospace and the like. With the continuous expansion of the application field of the power battery, the market demand of the power battery is also continuously expanding.

With the continuous expansion of the demand of the power battery, the use safety and the service life of the power battery are increasingly required.

The battery needs to be impregnated with an electrolyte solution into the interior of the electrode assembly before use. The electrode assembly is manufactured by winding or laminating the electrode plates, the total amount of electrolyte is sufficient in the initial stage of infiltration, and the electrolyte can submerge the whole height of the electrode plates and gradually infiltrate into the electrode assembly; however, as the electrolysis process is continuously carried out, the electrolyte is continuously consumed, the liquid level of free electrolyte is reduced, the electrolyte mainly enters the electrode assembly from the lower part of the electrode assembly through capillary action, and the electrolyte has limited climbing capacity, so that the infiltration speed and infiltration effect are poor, infiltration on the whole pole piece is difficult to finish, and the problem of poor infiltration exists at the middle upper part of the pole piece.

Specifically, in the electrolyte infiltration process, the infiltration rate can be gradually slowed down along with the increase of the height due to the influence of gravity, so that the problem of poor infiltration easily occurs in the upper middle region of the electrode assembly, and further serious consequences such as black spots, lithium precipitation and the like are caused in the battery use process, and the use safety and the service life of the battery are influenced. In addition, the outer side of the pole piece is fully contacted with the electrolyte, and the inner side of the pole piece cannot be directly contacted with the electrolyte, so that the problems of uneven infiltration, poor local infiltration and the like of the electrolyte at the inner layer and the outer layer of the surface of the pole piece can occur.

In order to alleviate the problems of black spots, lithium precipitation and the like, the application provides a pole piece with an improved structure, which comprises a current collector, an active layer and an interlayer, wherein the interlayer is arranged between the current collector and the active layer and can guide electrolyte to infiltrate the active layer, so that the electrolyte can infiltrate at the outer side of the active layer far from the current collector and the inner side close to the current collector at the same time, the infiltration of the electrolyte is accelerated, the infiltration speed is improved, and the time required by infiltration is shortened; due to the addition of the interlayer, the two sides inside and outside the active layer can be infiltrated simultaneously, so that the problem of uneven infiltration of the two sides inside and outside the pole piece is solved, and the overall uniformity of infiltration of the pole piece is improved; even if the electrolyte is affected by gravity, under the guiding action of the interlayer, the climbing rate of the electrolyte can be improved, so that the problem of poor infiltration of the upper region in the pole piece is solved, the problems of black spots, lithium precipitation and the like of the battery in the use process are reduced, and the use safety and the service life of the battery are improved.

The pole piece disclosed by the embodiment of the application can be used for preparing an electrode assembly, a battery monomer and a battery, and the battery monomer and the battery can be used in electric equipment such as vehicles, ships or aircrafts, but are not limited to the electric equipment. The power supply system of the electric equipment is composed of the battery monomer, the battery and the like, so that the problems of black spots, lithium precipitation and the like in the use process of the battery can be effectively relieved, and the use safety and the service life of the battery are improved.

The embodiment of the application provides electric equipment using a battery as a power supply, wherein the battery is configured to provide electric energy for the electric equipment. The powered device may be, but is not limited to, a cell phone, a portable device, a notebook computer, a battery car, an electric car, a ship, a spacecraft, an electric toy, and an electric tool, etc., for example, a spacecraft including an airplane, a rocket, a space plane, and a spacecraft, etc., an electric toy including a stationary or mobile electric toy, for example, a game console, an electric car toy, an electric ship toy, and an electric airplane toy, etc., an electric tool including a metal cutting electric tool, a grinding electric tool, a fitting electric tool, and a railway electric tool, for example, an electric drill, an electric grinder, an electric wrench, an electric screwdriver, an electric hammer, an impact electric drill, a concrete vibrator, and an electric planer.

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

Referring to fig. 1, fig. 1 is a schematic structural diagram of a vehicle 1000 according to some embodiments of the application. The vehicle 1000 may be a fuel oil vehicle, a gas vehicle or a new energy vehicle, and the new energy vehicle may be a pure electric vehicle, a hybrid vehicle or a range-extended vehicle. The battery 100 is provided in the interior of the vehicle 1000, and the battery 100 may be provided at the bottom or the head or the tail of the vehicle 1000. The battery 100 may be used for power supply of the vehicle 1000, for example, the battery 100 may be used as an operating power source of the vehicle 1000. The vehicle 1000 may also include a controller 200 and a motor 300, with the battery 100 being used to provide electrical power for operation of the motor 300 and other components in the vehicle, and the controller 200 being used to control operation of the motor 300, e.g., for operating power requirements during start-up, navigation, and travel of the vehicle 1000.

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

Referring to fig. 2, fig. 2 is an exploded view of a battery 100 according to some embodiments of the present application. The battery 100 includes a case 10 and a battery cell 20, and the battery cell 20 is accommodated in the case 10. The case 10 is used to provide an accommodating space for the battery cell 20, and the case 10 may have various structures. In some embodiments, the case 10 may include a first cover 101 and a second cover 102, where the first cover 101 and the second cover 102 are covered with each other, and the first cover 101 and the second cover 102 together define an accommodating space for accommodating the battery cell 20. The second cover 102 may have a hollow structure with an opening at one end, the first cover 101 may have a plate-shaped structure, and the first cover 101 is covered on the opening side of the second cover 102, so that the first cover 101 and the second cover 102 together define an accommodating space; the first cover 101 and the second cover 102 may each have a hollow structure with one side open, and the open side of the first cover 101 may be closed to the open side of the second cover 102. Of course, the case 10 formed by the first cover 101 and the second cover 102 may be of various shapes, such as a cylinder, a rectangular parallelepiped, or the like.

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

The battery cell 20 includes a lithium ion secondary battery, a lithium ion primary battery, a lithium sulfur battery, a sodium lithium ion battery, a sodium ion battery, a magnesium ion battery, or the like, which is not limited by the embodiment of the present disclosure. The battery cells may be cylindrical, flat, rectangular, or otherwise shaped, as well as embodiments of the present disclosure are not limited in this regard. The battery cells are generally classified into three types according to the packaging method: cylindrical battery cells, square battery cells, and pouch battery cells, nor are embodiments of the disclosure limited thereto.

Referring to fig. 3, fig. 3 is an exploded view of a battery cell 20 according to some embodiments of the present application. The battery cell 20 refers to the smallest unit constituting the battery 100. As shown in fig. 3, the battery cell 20 includes an electrode assembly 21, a case 22, and other functional components of an end cap 23.

The end cap 23 refers to a member that is covered at the opening of the case 22 to isolate the internal environment of the battery cell 20 from the external environment. Without limitation, the shape of the end cap 23 may be adapted to the shape of the housing 22 to fit the housing 22. Alternatively, the end cover 23 may be made of a material having a certain hardness and strength (such as an aluminum alloy), so that the end cover 23 is not easy to deform when being extruded and collided, so that the battery cell 20 can have a higher structural strength, and the safety performance can be improved. The end cap 23 may be provided with functional parts such as electrode terminals. The electrode terminals may be used to be electrically connected with the electrode assembly 21 for outputting or inputting electric power of the battery cell 20.

In some embodiments, the end cap 23 may also be provided with a pressure relief mechanism for relieving the internal pressure when the internal pressure or temperature of the battery cell 20 reaches a threshold.

In some embodiments, the end cap 23 may further be provided with a filling hole for filling the inside of the battery cell 20 with an electrolyte.

The material of the end cap 23 may be various, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., which is not particularly limited in the embodiment of the present application.

In some embodiments, insulation may also be provided on the inside of the end cap 23, which may be used to isolate electrical connection components within the housing 22 from the end cap 23 to reduce the risk of short circuits. By way of example, the insulation may be plastic, rubber, or the like.

The case 22 is an assembly for cooperating with the end cap 23 to form an internal environment of the battery cell 20, wherein the formed internal environment may be used to accommodate the electrode assembly 21, the electrolyte, and other components. The case 22 and the end cap 23 may be separate components, and an opening may be provided in the case 22, and the interior of the battery cell 20 may be formed by covering the opening with the end cap 23 at the opening. It is also possible to integrate the end cap 23 and the housing 22, but specifically, the end cap 23 and the housing 22 may form a common connection surface before other components are put into the housing, and when it is necessary to encapsulate the inside of the housing 22, the end cap 23 is then put into place on the housing 22. The housing 22 may be of various shapes and sizes, such as rectangular parallelepiped, cylindrical, hexagonal prism, etc. Specifically, the shape of the case 22 may be determined according to the specific shape and size of the electrode assembly 21. The material of the housing 22 may be various, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., which is not particularly limited in the embodiment of the present application.

The electrode assembly 21 is a component in which electrochemical reactions occur in the battery cells 20. One or more electrode assemblies 21 may be contained within the case 22. The electrode assembly 21 is mainly formed by winding or stacking a positive electrode sheet and a negative electrode sheet, and a separator is generally provided between the positive electrode sheet and the negative electrode sheet. The portions of the positive and negative electrode sheets having the active material constitute the main body portion of the electrode assembly 21, and the portions of the positive and negative electrode sheets having no active material constitute the tabs, respectively. The positive electrode tab and the negative electrode tab may be located at one end of the main body portion together or located at two ends of the main body portion respectively. During charge and discharge of the battery 100, the positive and negative electrode active materials react with the electrolyte, and the tab is connected to the electrode terminal to form a current loop. The separator serves to separate the positive electrode sheet and the negative electrode sheet, and to prevent electrons in the battery cell 20 from freely passing therethrough, so that ions in the electrolyte freely flow between the positive electrode sheet and the negative electrode sheet. The separator may be a film member made of PE (polyethylene), PP (polypropylene), or the like.

Fig. 4a is a schematic structural diagram of a pole piece in the related art. In this scheme, the pole piece includes current collector 1 and active layer 2, and active layer 2 is provided on the surface of current collector 1.

As shown in fig. 4b, when the electrolyte is infiltrated, the outer side of the active layer 2 away from the current collector 1 may directly contact the electrolyte, and the inner side of the active layer 2 cannot directly contact the electrolyte due to the close proximity to the current collector 1, so that the electrolyte can only infiltrate from the outer side of the active layer 2 away from the current collector 1 to the inner side close to the current collector 1, and the infiltration speed is slow. Moreover, the inner side close to the current collector 1 cannot be directly contacted with the electrolyte, and only the electrolyte at the outer side can be used for inwards diffusing, so that the infiltration effect is poor, and the problem of uneven infiltration at the two sides can occur; in addition, as the electrolyte is consumed, the height of the electrolyte is reduced, the bottom electrolyte needs to climb upwards to infiltrate the upper part of the active layer 2, but under the action of gravity, the capacity of climbing upwards of the bottom electrolyte is limited, the problem of poor infiltration of the active layer 2 can occur locally, and serious consequences such as black spots, lithium precipitation and the like can be caused in the use process of the battery, so that the use safety and the service life of the battery are affected.

As shown in fig. 5a, a schematic structural diagram of some embodiments of the pole piece provided by the present application is shown. In the pole piece embodiment provided by the application, the pole piece comprises a current collector 1, an active layer 2 and an interlayer 3, wherein the current collector 1 is configured to collect electrons to form an electron flow, the active layer 2 is configured to insert or extract ions, the interlayer 3 is arranged between the active layer 2 and the current collector 1, and the interlayer 3 is configured to guide electrolyte to infiltrate the active layer 2.

The current collector 1 collects the current generated by the battery active material so as to form a large current to be outputted to the outside. The active layer 2 is made of an active material, and can store and release electric charges during charge and discharge, thereby realizing electrochemical energy storage and conversion functions of the battery.

Taking a lithium ion battery as an example, the material of the current collector 1 in the positive electrode plate can be aluminum, and the material of the active layer 2 can be lithium cobaltate, lithium iron phosphate, ternary lithium or lithium manganate and the like. The material of the current collector 1 in the negative electrode sheet can be copper, and the material of the active layer 2 can be carbon or silicon.

The interlayer 3 is a substance provided between the active layer 2 and the current collector 1. The interlayer 3 may be a coating material coated on the surface of the current collector 1 or the active layer 2. The interlayer 3 may be a separately molded member and may be provided on the surface of the current collector 1 or the active layer 2 by adhesion or the like. The material used for the interlayer 3 can absorb and guide the electrolyte diffusion.

As shown in fig. 5b, by arranging the interlayer 3, the electrolyte can be led to infiltrate the active layer 2, so that the electrolyte can infiltrate into the active layer 2 at the outer side of the active layer 2 far from the current collector 1 and the inner side close to the current collector 1, the infiltration is faster and more sufficient, and the time required for infiltration is effectively shortened; due to the addition of the interlayer 3, the inner side and the outer side of the active layer 2 can be infiltrated simultaneously, so that the infiltration effect of the inner side of the active layer 2 is improved, the problem of uneven infiltration of the inner side and the outer side of the pole piece is solved, and the overall uniformity of infiltration of the pole piece is improved; even if the electrolyte is affected by gravity, the climbing rate of the electrolyte can be improved under the guiding action of the interlayer 3, so that the problem of poor infiltration of the upper region in the pole piece is solved, the problems of black spots, lithium precipitation and the like of the battery in the use process are reduced, and the use safety and the service life of the battery are improved.

Referring to fig. 6 to 10, in some embodiments, the interlayer 3 includes a plurality of interlayer bodies 31, and the plurality of interlayer bodies 31 are arranged at intervals along a preset direction.

The interlayer body 31 is an integral part of the interlayer 3, and a plurality of interlayer bodies 31 arranged at intervals form the interlayer 3. The shape and size of the plurality of sandwich bodies 31 may be the same or different.

Compared with the scheme of arranging the whole interlayer between the current collector 1 and the active layer 2, the embodiment of the application can reduce the total area of the interlayer 3 and save the material of the interlayer 3 by arranging the interlayer bodies 31 which are arranged at intervals, thereby reducing the cost of the pole piece.

Although no electrolyte is introduced into the region between the adjacent two sandwich bodies 31 through the sandwich bodies 31, the electrolyte introduced into the sandwich bodies 31 is diffused to both sides into the region between the adjacent two sandwich bodies 31, and thus the region can be infiltrated.

The plurality of interlayer bodies 31 may be arranged at intervals in a variety of different directions, such as may be arranged at intervals in a horizontal direction, at intervals in a vertical direction, or in an inclined direction having a predetermined angle with the horizontal direction, etc.

In some embodiments, a plurality of sandwich bodies 31 are spaced apart along the winding direction of the pole piece.

As shown in fig. 6, which is a schematic view of the pole piece after being unwound, the winding direction is shown, and the pole piece is wound in the winding direction.

The electrode assembly is generally vertically placed, the plurality of interlayer bodies 31 are arranged at intervals along the winding direction of the pole piece, and the interlayer bodies 31 can extend along the vertical direction, so that electrolyte is guided to climb upwards along the vertical direction, the infiltration speed of the electrolyte is increased, and the infiltration effect is improved.

In the embodiment shown in fig. 6, the sandwich body 31 extends in the vertical direction, and the width of the sandwich body 31 remains unchanged in the bottom-up direction.

Wherein the vertical direction is parallel to the direction of the gravitational force to which the object is subjected.

In some embodiments, the sandwich body 31 extends in a vertical direction, and the width of the sandwich body 31 decreases in a bottom-up direction.

The width of the interlayer body 31 is reduced along the direction from bottom to top, namely the width of the bottom of the interlayer body 31 is larger, more electrolyte can be guided to climb upwards through the bottom of the interlayer body 31, the upward climbing distance of the electrolyte is increased, the problem of poor infiltration of the upper region in the pole piece is relieved, the problems of black spots, lithium precipitation and the like in the subsequent battery use process are reduced, the use safety of the battery is improved, and the service life of the battery is prolonged; meanwhile, the width of the top of the interlayer body 31 is smaller, the upper area of the interlayer body 31 can be reduced, materials are saved, and cost is saved.

The width of the interlayer body 31 decreases in the bottom-up direction, which may include a stepwise decrease in the width of the interlayer body 31 in the bottom-up direction as shown in fig. 7, or may include a gradual decrease in the width of the interlayer body 31 in the bottom-up direction as shown in fig. 8 to 10.

As shown in fig. 8-10, in some embodiments, the width of the sandwich body 31 gradually decreases in a bottom-up direction.

The width of the interlayer body 31 is gradually reduced along the direction from bottom to top, so that a trend of uniform reduction can be formed along the direction from bottom to top, and the climbing speed of the electrolyte is more uniform.

The edges of the sandwich body 31 extending in the vertical direction may be straight or curved.

The edge of the interlayer body 31 extending along the vertical direction is straight, so that the edge of the interlayer body 31 is regular, and the attractive appearance and the uniformity are good.

The edge of the interlayer body 31 extending along the vertical direction is bent, so that the flatness requirement of the edge of the interlayer body 31 can be reduced, and the manufacturing difficulty can be reduced.

As shown in fig. 6 and 8, the edges of the sandwich body 31 extending in the vertical direction are straight; as shown in fig. 7, the edges of the sandwich body 31 extending in the vertical direction are stepped, and the edges of each segment of the sandwich body 31 extending in the vertical direction are straight; in other embodiments, the edges of the sandwich body 31 extending in the vertical direction are stepped, and the edges of each segment of the sandwich body 31 extending in the vertical direction may also be curved; in the embodiment shown in fig. 9 and 10, the edges of the sandwich body 31 extending in the vertical direction are curved.

The shape of the sandwich body 31 may be chosen in a number of ways. For example, as shown in fig. 6, the shape of the interlayer body 31 is rectangular, and the width of the interlayer body 31 is kept constant in the bottom-up direction. The sandwich body 31 is regular in shape and good in aesthetic appearance and uniformity.

As shown in fig. 7, the shape of the interlayer body 31 is in a stepped shape, and the interlayer body 31 is in a sectional design, so that different sizes can be set according to requirements. In the bottom-up direction, the width of the sandwich body 31 of the plurality of gradients gradually decreases, but the width of the sandwich body 31 in each gradient remains unchanged, and the edges of the sandwich body 31 extending in the vertical direction in each gradient are straight.

As shown in fig. 8, the shape of the interlayer body 31 is an isosceles trapezoid, and the edges of the interlayer body 31 extending in the vertical direction are straight, and the width of the interlayer body 31 gradually decreases in the bottom-up direction. The lower part width of intermediate layer body 31 is great, can absorb more electrolyte through the lower part of intermediate layer body 31 like this, satisfies the demand of climbing upwards, and upper portion width is narrower simultaneously, can reduce the area on intermediate layer body 31 upper portion, saves materials, practices thrift the cost.

As shown in fig. 9, the interlayer body 31 has a long strip shape, the width of the interlayer body 31 gradually decreases in the bottom-up direction, the edge of the interlayer body 31 extending in the vertical direction is curved, and the curved direction is fixed.

As shown in fig. 10, the interlayer body 31 has a long strip shape, the width of the interlayer body 31 gradually decreases in the bottom-up direction, the edge of the interlayer body 31 extending in the vertical direction is curved, and the curved direction is changeable.

As shown in fig. 11, a cross-sectional view of some embodiments of pole pieces, i.e., a cross-sectional view taken along a section perpendicular to the direction of extension of the sandwich body 31, is shown. As can be seen from this figure, a plurality of interlayer bodies 31 are disposed between the current collector 1 and the active layer 2 at intervals.

As shown in fig. 12, a schematic immersion diagram of a rectangular sandwich body 31 is shown. The electrolyte starts to climb upwards from the bottom of the interlayer body 31, and during climbing, the climbing speed of the two sides is gradually smaller than that of the middle.

As shown in fig. 13, a schematic immersion diagram of the trapezoid-shaped interlayer body 31 is shown. The electrolyte starts climbing upwards from the bottom of the interlayer body 31, and the electrolyte is sufficient because the bottom of the interlayer body 31 is wider, so that the climbing speeds of the two sides are basically equal to the climbing speed in the middle in the climbing process.

In some embodiments, the active layer 2 is arranged in a vertical direction, with the sandwich body 31 extending from the bottom to the top of the active layer 2.

The interlayer body 31 is arranged to extend from the bottom of the active layer 2 to the top, so that the interlayer body 31 can guide electrolyte to climb upwards from the bottom of the active layer 2, and the interlayer body 31 can still be contacted with the electrolyte after the electrolyte storage amount is reduced.

In some embodiments, the active layer 2 is arranged in a vertical direction, with the sandwich body 31 extending from the bottom to the top of the active layer 2 and to the top of the active layer 2.

The interlayer body 31 is arranged to extend from the bottom of the active layer 2 to the top and to the top of the active layer 2, so that the interlayer body 31 can be fully distributed with the whole height of the active layer 2 in the vertical direction, and the guiding effect on the electrolyte is achieved in the whole height direction, and the infiltration effect of the active layer 2 in the whole height is improved.

In some embodiments, the gap between two adjacent sandwich bodies 31 is less than the maximum width of the sandwich bodies 31.

The gap between two adjacent interlayer bodies 31 is set to be smaller than the maximum width of the interlayer bodies 31, so that the infiltration effect of the area between the two adjacent interlayer bodies 31 can be effectively ensured, and the probability that the area in the gap cannot be infiltrated with electrolyte due to too large gap between the two adjacent interlayer bodies 31 is reduced.

In some embodiments, the material of the interlayer 3 is a porous material, a multichannel tubular nanomaterial, or a polymeric material having an electrolyte-philic group.

The porous material is a material with a network structure formed by mutually communicated or closed holes, such as activated carbon, silicon dioxide or aluminum oxide and the like. The material can absorb and contain more electrolyte due to the holes, and the flowing speed of the electrolyte in the material is higher.

The multichannel tubular nanomaterial is a tubular material made of nanomaterial having a plurality of channels. The material has multiple channels, can absorb and contain more electrolyte, and has higher flow speed of the electrolyte.

The polymer material with the electrolyte-philic group comprises polysulfone (Polysulfone, PSF for short) or polyethylene glycol (Polyethylene Glycol, PEG for short) and the like. The material has electrolyte-philic groups, so that the electrolyte can be attracted to be close, more electrolyte is accumulated, and the diffusion speed of the electrolyte is increased.

In some embodiments, the pole piece comprises a plurality of interlayers 3, the interlayers 3 being arranged in superposition in the direction of the active layer 2 pointing towards the current collector 1.

Through the overlapping arrangement of a plurality of interlayers 3 along the direction of the active layer 2 pointing to the current collector 1, the method is equivalent to arranging a plurality of layers of interlayers 3 between the current collector 1 and the active layer 2, the total thickness and the total area of the interlayers 3 are increased, the guiding effect of the interlayers 3 on electrolyte is further enhanced, and the infiltration effect of the electrolyte is improved.

In some embodiments, the pole piece further comprises a first tab 4 and a second tab 5 disposed on the current collector 1.

The first tab 4 and the second tab 5 can be independently formed relative to the current collector 1 and connected with the current collector 1; or the first tab 4, the second tab 5 and the current collector 1 are integrally formed. The first tab 4 and the second tab 5 may be uncoated with an interlayer material or an active material. The current collected by the current collector 1 is led out through the first tab 4 and the second tab 5, and a circuit is generated.

The first tab 4 and the second tab 5 may be a positive tab and a negative tab, respectively. The first tab 4 and the second tab 5 may be disposed on the same side of the current collector 1, or may be disposed on different sides of the current collector 1. The first tab 4 and the second tab 5 may be disposed on the top of the current collector 1, or may be disposed on a side surface of the current collector 1.

Based on the pole pieces in the above embodiments, the application also provides a battery cell comprising the pole piece, a battery comprising the battery cell and electric equipment comprising the battery.

The battery monomer, the battery and the electric equipment manufactured by the pole piece provided by the embodiments of the application can improve the infiltration effect of the pole piece, relieve the problems of black spots, lithium precipitation and the like in the use process of the battery, and improve the use safety and the service life of the battery.

As shown in fig. 14, the present application also provides a roller 6, wherein the roller 6 includes a roller shaft 61, the interlayer 3 is coated on the outer circumferential surface of the roller shaft 61, and the roller shaft 61 is configured to roll relative to the current collector 1 to coat the interlayer 3 on the current collector 1, thereby forming the pole piece.

The roller 6 is a component for manufacturing the pole piece. When manufacturing the pole piece, the interlayer material is coated on the outer peripheral surface of the roller shaft 61, then the roller shaft 61 rotates relative to the current collector 1, the interlayer material is coated on the current collector 1 in the rotating process of the roller shaft 61, thus forming the current collector 1 with the interlayer 3, and finally the active material is coated on the current collector 1 with the interlayer 3, thus forming the pole piece.

In some embodiments, the roller 61 is cylindrical in shape to facilitate application of the sandwich material to the current collector 1 during rotation.

In some embodiments, the roller member 6 further includes a plurality of protrusions 62 disposed on the outer circumferential surface of the roller shaft 61 and arranged at intervals in the circumferential direction, and the interlayer 3 is applied to the protrusions 62.

By providing the plurality of protrusions 62, the interlayer 3 coated on the current collector 1 may be made to include the plurality of interlayer bodies 31 arranged at intervals.

The convex portions 62 protrude radially outward from the outer peripheral surface of the roller shaft 61 with a gap between adjacent two of the convex portions 62.

The shape of the protruding portion 62 may be selected in various ways, and the shape of the protruding portion 62 may be matched with the shape of the sandwich body 31, so that the coating is facilitated. For example, the outer side of the protrusion 62 for coating the interlayer material may be rectangular, trapezoidal, stepped, or the like.

The structure of one embodiment of the pole piece provided by the application is described below.

As shown in fig. 5a, the pole piece comprises a current collector 1, an active layer 2 and an interlayer 3, the interlayer 3 being arranged between the active layer 2 and the current collector 1. The coverage of the interlayer 3 is not smaller than that of the active layer 2.

As shown in fig. 5b, the outer side of the active layer 2 far away from the current collector 1 can be directly contacted with electrolyte, and the inner side of the active layer 2 close to the current collector 1 can also be contacted with electrolyte through the guide of the interlayer 3, so that the effect that the electrolyte infiltrates into the active layer 2 from the inner side and the outer side of the active layer 2 simultaneously is realized, the infiltration speed is greatly improved, and the problem of uneven infiltration of the inner side and the outer side is solved. The climbing rate of the electrolyte can be improved through the guide of the interlayer 3, and the problem of poor infiltration of the middle and upper parts of the pole piece is relieved.

As shown in fig. 8, the interlayer 3 includes a plurality of interlayer bodies 31 arranged at intervals. The pole piece further comprises a first pole lug 4 and a second pole lug 5 which are connected with the current collector 1.

In this embodiment, the shape of the sandwich body 31 is an isosceles trapezoid, the edges of the sandwich body 31 extending in the vertical direction are straight, and the width of the sandwich body 31 gradually decreases in the bottom-up direction.

As shown in fig. 11, as can be seen from the cut-out of the pole piece, a plurality of interlayer bodies 31 are disposed between the current collector 1 and the active layer 2 at intervals.

As shown in fig. 13, when the electrolyte is guided to climb up, the ladder-shaped sandwich body 31 has a wide bottom and sufficient electrolyte, so that the climbing speed at both sides is substantially equal to the climbing speed in the middle during climbing.

The foregoing description of various embodiments is intended to highlight differences between the various embodiments, which may be the same or similar to each other by reference, and is not repeated herein for the sake of brevity.

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

Claims (16)

1. A pole piece, comprising:

A current collector (1) configured to collect electrons to form an electron flow;

an active layer (2) configured to intercalate or deintercalate ions; and

-An interlayer (3) arranged between the active layer (2) and the current collector (1), the interlayer (3) being configured to direct an electrolyte to infiltrate the active layer (2);

Wherein the interlayer (3) comprises a plurality of interlayer bodies (31), and the plurality of interlayer bodies (31) are arranged at intervals along a preset direction.

2. Pole piece according to claim 1, characterized in that a plurality of the sandwich bodies (31) are arranged at intervals along the winding direction of the pole piece.

3. Pole piece according to claim 1, characterized in that the sandwich body (31) extends in a vertical direction and the width of the sandwich body (31) decreases in a bottom-up direction.

4. A pole piece according to claim 3, characterized in that the width of the sandwich body (31) decreases gradually in a bottom-up direction.

5. Pole piece according to claim 1, characterized in that the edges of the sandwich body (31) extending in the vertical direction are straight or curved.

6. Pole piece according to claim 1, characterized in that the sandwich body (31) is trapezoidal, stepped or rectangular in shape.

7. Pole piece according to claim 1, characterized in that the active layer (2) is arranged in a vertical direction, the sandwich body (31) extending from the bottom to the top of the active layer (2).

8. Pole piece according to claim 1, characterized in that the active layer (2) is arranged in a vertical direction, the sandwich body (31) extending from the bottom to the top of the active layer (2) and to the top of the active layer (2).

9. Pole piece according to claim 1, characterized in that the gap between two adjacent sandwich bodies (31) is smaller than the maximum width of the sandwich bodies (31).

10. Pole piece according to claim 1, characterized in that the material of the interlayer (3) is a porous material, a multichannel tubular nanomaterial or a polymeric material with an electrolyte-philic group.

11. A pole piece according to any of claims 1-10, characterized in that the pole piece comprises a plurality of the interlayers (3), the interlayers (3) being arranged in a superimposed manner in the direction of the active layer (2) pointing towards the current collector (1).

12. A battery cell (20) comprising a housing and an electrode assembly (21), the electrode assembly (21) being housed in the housing, the electrode assembly (21) comprising a positive electrode sheet, a negative electrode sheet and a separator provided between the positive electrode sheet and the negative electrode sheet, the positive electrode sheet and/or the negative electrode sheet being the electrode sheet according to any one of claims 1 to 11.

13. A battery (100) comprising a battery cell (20) according to claim 12.

14. A powered device comprising a battery (100) as claimed in claim 13, the battery (100) being arranged to supply electrical energy to the powered device.

15. A roller (6) for manufacturing a pole piece according to any one of claims 1 to 11, characterized by comprising a roller shaft (61), the interlayer (3) being applied to the outer circumferential surface of the roller shaft (61), the roller shaft (61) being configured to roll relative to the current collector (1) to apply the interlayer (3) to the current collector (1) to form the pole piece according to any one of claims 1 to 11.

16. The roller (6) according to claim 15, wherein the roller (6) further comprises a plurality of protrusions (62) provided on the outer peripheral surface of the roller shaft (61) and arranged at intervals in the circumferential direction, and the interlayer (3) is applied to the protrusions (62).