CN117133928A - Current collector, pole piece, electrode assembly, battery monomer, battery and power utilization device - Google Patents

Current collector, pole piece, electrode assembly, battery monomer, battery and power utilization device Download PDF

Info

Publication number
CN117133928A
CN117133928A CN202210551576.1A CN202210551576A CN117133928A CN 117133928 A CN117133928 A CN 117133928A CN 202210551576 A CN202210551576 A CN 202210551576A CN 117133928 A CN117133928 A CN 117133928A
Authority
CN
China
Prior art keywords
current collector
active material
material layer
pole piece
battery
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CN202210551576.1A
Other languages
Chinese (zh)
Inventor
郭锁刚
付成华
叶永煌
常雯
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Contemporary Amperex Technology Co Ltd
Original Assignee
Contemporary Amperex Technology Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Contemporary Amperex Technology Co Ltd filed Critical Contemporary Amperex Technology Co Ltd
Priority to CN202210551576.1A priority Critical patent/CN117133928A/en
Priority to PCT/CN2023/080133 priority patent/WO2023221606A1/en
Publication of CN117133928A publication Critical patent/CN117133928A/en
Pending legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/04—Processes of manufacture in general
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/04—Processes of manufacture in general
    • H01M4/0402—Methods of deposition of the material
    • H01M4/0404—Methods of deposition of the material by coating on electrode collectors
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/04—Processes of manufacture in general
    • H01M4/043—Processes of manufacture in general involving compressing or compaction
    • H01M4/0435—Rolling or calendering
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/64—Carriers or collectors
    • H01M4/66—Selection of materials
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/64—Carriers or collectors
    • H01M4/66—Selection of materials
    • H01M4/665—Composites
    • H01M4/667—Composites in the form of layers, e.g. coatings
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/64—Carriers or collectors
    • H01M4/70—Carriers or collectors characterised by shape or form
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/10—Energy storage using batteries

Landscapes

  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Materials Engineering (AREA)
  • Composite Materials (AREA)
  • Battery Electrode And Active Subsutance (AREA)

Abstract

The application provides a current collector, a pole piece, an electrode assembly, a battery monomer, a battery and an electricity utilization device, and belongs to the technical field of batteries. Wherein, the current collector includes body portion and strengthening protruding. The body portion has two coating surfaces disposed opposite to each other in a thickness direction of the current collector. The reinforcing protrusion is protruded from at least one of the two coating surfaces. In the pole piece with the current collector, the contact area between the active material layer and the current collector can be increased, so that on one hand, the bonding strength between the current collector and the active material layer is improved, and the contact resistance between the current collector and the active material layer is reduced, on the other hand, the structural strength of the current collector can be increased, the minimum thickness requirement of the current collector is reduced, the structural strength of the current collector is ensured, meanwhile, the containing amount of the active material layer of the pole piece can be effectively increased for the pole piece with the same overall thickness, and the preservation capacity of the pole piece for electrolyte can be improved.

Description

Current collector, pole piece, electrode assembly, battery monomer, battery and power utilization device
Technical Field
The application relates to the technical field of batteries, in particular to a current collector, a pole piece, an electrode assembly, a battery monomer, a battery and an electricity utilization device.
Background
In recent years, new energy automobiles have been developed dramatically, and in the field of electric automobiles, a power battery plays an important role as a power source of the electric automobile. Along with the great popularization of new energy automobiles, the demand for power battery products is also growing, wherein batteries as core components of the new energy automobiles have higher requirements on the aspects of cycle service life, service performance and the like. The battery cell is obtained by assembling an electrode assembly (bare cell) by winding or laminating a positive electrode plate, a negative electrode plate and a separation film, then filling the electrode assembly into a shell, and then injecting electrolyte. However, the battery in the prior art has the problems that the energy density is difficult to effectively improve and the service performance is poor in the using process.
Disclosure of Invention
The embodiment of the application provides a current collector, a pole piece, an electrode assembly, a battery monomer, a battery and an electricity utilization device, which can effectively improve the energy density and the service performance of the battery.
In a first aspect, embodiments of the present application provide a current collector including a body portion and a reinforcing protrusion; the body part is provided with two coating surfaces which are oppositely arranged along the thickness direction of the current collector; the reinforcing protrusion is protruded from at least one of the two coating surfaces.
In the above technical scheme, the reinforcing protrusions are arranged on the coating surface of at least one side of the body part, that is, the concave-convex structure is formed on the side of the current collector for coating the active material layer, so that in the pole piece with the current collector, the contact area between the active material layer of the pole piece and the current collector can be increased, on one hand, the bonding strength of the current collector and the active material layer is improved, on the other hand, the risk that the active material layer falls off in the use process of the pole piece is reduced, on the other hand, the contact resistance between the current collector and the active material layer is reduced, and the cycle service life of the battery monomer can be effectively prolonged. In addition, the structural strength of the current collector can be further increased through the reinforcing protrusions, the minimum thickness requirement of the current collector is reduced, the structural strength of the current collector is ensured, meanwhile, the pole piece of the current collector with the structure can effectively increase the containing amount of the active material layer in the pole piece with the same overall thickness, the storage capacity of the pole piece to electrolyte can be improved, and therefore the energy density and the service performance of a battery monomer are improved.
In some embodiments, the maximum dimension of the current collector is D in the thickness direction of the current collector 1 The minimum thickness of the body part is D 2 Satisfy D 1 -D 2 ≥0.5μm。
In the technical scheme, the difference between the maximum dimension of the current collector in the thickness direction and the minimum thickness of the body part is set to be larger than 0.5 mu m, so that the dimension of the reinforcing protrusion protruding out of the coating surface of the body part is ensured, and the phenomenon that the structural strength of the current collector cannot be achieved due to insufficient dimension of the reinforcing protrusion can be relieved.
In some embodiments, the current collector has an equivalent thickness D 3 Satisfies that D is less than or equal to 1 mu m 3 Less than or equal to 20 mu m; wherein D is 3 ＝m/(ρ×S 1 ) The mass of the current collector is m, the density of the current collector is ρ, and the area of the coating surface is S 1 。
In the technical scheme, the equivalent thickness of the current collector is set to be 1-20 mu m, namely, in the pole piece with the same thickness, the current collector with the structure has smaller equivalent thickness, so that more spaces are reserved on the side provided with the reinforcing protrusions for accommodating the active material layers, more active material layers can be accommodated, the accommodating quantity of the active material layers of the pole piece can be effectively improved while the structural strength of the current collector is ensured, and the energy density of the pole piece with the current collector is improved.
In some embodiments, the body portion has a thickness D 4 Satisfies D of 0.5 μm 4 ≤10μm。
In the technical scheme, the thickness of the body part is set to be 0.5 mu m to 10 mu m, so that the risk of fracture of the current collector in the use process due to the fact that the thickness of the body part is too small can be reduced, and the phenomena of too much occupied space and too large occupied weight of the current collector due to the fact that the thickness of the body part is too large can be reduced.
In some embodiments, the area of the end surface of the reinforcing protrusion facing away from the end of the body portion in the thickness direction of the current collector is S 2 The area of the coating surface is S 1 Meets the requirements of 0.1 to less than or equal to (S) 2 ×n)/S 1 Less than or equal to 0.9; wherein n is the number of the reinforcing protrusions on the coated surface.
In the above technical scheme, the ratio of the total area of the end surface of the reinforcing protrusion, which is far away from the body, to the area of the coating surface of the body is set to be 0.1 to 0.9, so that on one hand, the risk that the bonding strength between the current collector and the active material layer is lower and the contact area is insufficient due to the fact that the total area of the end surface of the reinforcing protrusion occupies too little coating surface can be reduced, and on the other hand, the phenomenon that the space for accommodating the active material layer is too little due to the fact that the total area of the end surface of the reinforcing protrusion occupies too much coating surface can be relieved, and therefore the accommodating amount of the current collector to the active material layer can be guaranteed.
In some embodiments, the reinforcing protrusion is a strip-shaped structure extending along a straight line track, and the extending direction of the reinforcing protrusion is perpendicular to the thickness direction of the current collector.
In the above technical solution, the reinforcing protrusions are provided in a strip-shaped structure, and extend in a direction perpendicular to the thickness direction of the current collector, so that the reinforcing protrusions of such a structure are beneficial to improving the mechanical strength and the structural strength of the current collector.
In some embodiments, the elongation at break of the current collector is e, satisfying 1.1% or less e or less than 8%.
In the technical scheme, the breaking elongation of the current collector is set to be 1.1-8% so as to ensure the mechanical strength of the current collector, thereby reducing the phenomenon that the current collector breaks or is damaged in the use process and being beneficial to prolonging the service life of the current collector.
In some embodiments, the coated surface is convexly provided with a plurality of the reinforcing protrusions.
In the technical scheme, the plurality of reinforcing protrusions are arranged on the coating surface of the body part, so that the structural strength of the current collector can be further improved, the service life of the current collector is prolonged, the contact area between the current collector and the active material layer can be further improved, the contact resistance between the current collector and the active material layer is reduced, and the connection stability between the current collector and the active material layer is improved.
In some embodiments, both of the coated surfaces are convexly provided with the reinforcing protrusions.
In the above technical scheme, through all setting up the enhancement arch at two coating surfaces of body portion, that is to say, the body portion all is protruding to be equipped with the enhancement arch in the both sides of the thickness direction of mass flow body to on the one hand be favorable to further increasing the overall structure intensity of mass flow body, on the other hand can promote the area of contact of both sides and the active material layer of mass flow body, and can promote the holding capacity of the active material layer of both sides of mass flow body, and then be favorable to promoting the overall performance of the pole piece of mass flow body that has this kind of structure.
In a second aspect, an embodiment of the present application further provides a pole piece, including an active material layer and the current collector described above; the active material layer is coated on the coated surface.
In the technical scheme, the pole piece with the structure can effectively increase the contact area between the current collector and the active material layer on one hand, thereby being beneficial to improving the bonding strength and the connection stability of the current collector and the active material layer, reducing the contact resistance between the current collector and the active material layer, effectively increasing the containing amount of the active material layer of the pole piece on the other hand, improving the preservation capacity of the pole piece to electrolyte, and improving the energy density of the pole piece, thereby improving the service performance of the pole piece.
In some embodiments, the body portion has a region of weakness, and the active material layer covers the region of weakness.
In the technical scheme, the weak area is arranged on the body part and is covered with the active material layer, so that the weak area can play a certain role in preserving electrolyte, and further the preservation capacity of the pole piece to the electrolyte is improved, and the service performance of the pole piece is improved.
In a third aspect, an embodiment of the present application further provides an electrode assembly including the above-mentioned electrode sheet.
In a fourth aspect, an embodiment of the present application further provides a battery cell, including a case and the above-described electrode assembly; the electrode assembly is accommodated in the case.
In a fifth aspect, an embodiment of the present application further provides a battery, including a plurality of the foregoing battery cells.
In a sixth aspect, an embodiment of the present application further provides an electrical apparatus, including the above-mentioned battery.
In a seventh aspect, an embodiment of the present application further provides a method for manufacturing a pole piece, including: providing a current collector, wherein the current collector comprises a body part and a reinforcing protrusion, the body part is provided with two coating surfaces which are oppositely arranged along the thickness direction of the current collector, and the reinforcing protrusion is convexly arranged on at least one of the two coating surfaces; an active material layer is coated on the coated surface.
In some embodiments, after the active material layer is coated on the coated surface, the method of manufacturing the pole piece further comprises: cold pressing the active material layer to press a portion of the active material layer into the body portion, the body portion forming a weakened area at a location pressed by the portion of the active material layer.
In the technical scheme, the active material layer arranged on the coating surface is subjected to cold pressing, so that part of particles of the active material layer can be pressed into the body part, a weak area is formed on the body part, and the weak area can play a certain role in preserving electrolyte, so that the preservation capacity of the pole piece to the electrolyte is improved.
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 will be briefly described below, it being understood that the following drawings only illustrate some embodiments of the present application and therefore should not be considered as limiting the scope, and other related drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.
FIG. 1 is a schematic illustration of a vehicle according to some embodiments of the present application;
Fig. 2 is an exploded view of a battery according to some embodiments of the present application;
fig. 3 is a structural exploded view of a battery cell according to some embodiments of the present application;
fig. 4 is a cross-sectional view of an electrode assembly provided in some embodiments of the application;
FIG. 5 is a schematic view of a partial structure of a pole piece according to some embodiments of the present application;
FIG. 6 is a top view of a current collector provided by some embodiments of the present application;
FIG. 7 is a partial cross-sectional view of a current collector provided in some embodiments of the application;
fig. 8 is a top view of a current collector provided in further embodiments of the present application;
fig. 9 is a top view of a current collector provided in accordance with still other embodiments of the present application;
fig. 10 is a partial cross-sectional view of a current collector provided in accordance with still other embodiments of the present application;
FIG. 11 is a top view of a current collector provided by other embodiments of the present application;
fig. 12 is a cross-sectional view of a current collector provided in some embodiments of the application in other embodiments;
fig. 13 is a flow chart of a method for manufacturing a pole piece according to some embodiments of the present application.
Icon: 1000-vehicle; 100-cell; 10-a box body; 11-a first tank body; 12-a second tank body; 20-battery cells; 21-a housing; 211-a housing; 2111-opening; 212-end caps; 22-electrode assembly; 221-pole piece; 2211—a current collector; 2211 a-a body portion; 2211 b-reinforcing protrusions; 2211 c-coated surface; 2212-an active material layer; 222-a separator; 23-positive electrode terminal; 24-a negative electrode terminal; 25-a pressure release mechanism; 200-a controller; 300-motor; thickness direction of X-current collector; y-the length direction of the current collector; width direction of Z-current collector.
Detailed Description
For the purpose of making the objects, technical solutions and advantages of the embodiments of the present application more apparent, the technical solutions of the embodiments of the present application will be clearly described below with reference to the accompanying drawings in the embodiments of the present application, and it is apparent that the described embodiments are some embodiments of the present application, but not all embodiments of the present application. All other embodiments, which can be made by those skilled in the art based on the embodiments of the application without making any inventive effort, are intended to be within the scope of the 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 in the description of the application 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. The terms first, second and the like in the description and in the claims or in the above-described figures, are used for distinguishing between different objects and not necessarily for describing a particular sequential or chronological order.
Reference in the specification 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.
In the description of the present application, it should be noted that, unless explicitly specified and limited otherwise, the terms "mounted," "connected," and "attached" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; can be directly connected or indirectly connected through an intermediate medium, and can be communication between two elements. The specific meaning of the above terms in the present application can be understood by those of ordinary skill in the art according to the specific circumstances.
The term "and/or" in the present application is merely an association relation describing the association object, and indicates that three kinds of relations may exist, for example, a and/or B may indicate: a exists alone, A and B exist together, and B exists alone. In the present application, the character "/" generally indicates that the front and rear related objects are an or relationship.
In the embodiments of the present application, the same reference numerals denote the same components, and detailed descriptions of the same components are omitted in different embodiments for the sake of brevity. It should be understood that the thickness, length, width, etc. dimensions of the various components in the embodiments of the application shown in the drawings, as well as the overall thickness, length, width, etc. dimensions of the integrated device, are merely illustrative and should not be construed as limiting the application in any way.
The term "plurality" as used herein refers to two or more (including two).
In the present application, the battery cell may include 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 in the embodiment of the present application. The battery cell may be in a cylindrical shape, a flat shape, a rectangular parallelepiped shape, or other shapes, which is not limited in this embodiment of the application. The battery cells are generally classified into three types according to the packaging method: the cylindrical battery cell, the square battery cell and the soft package battery cell are not limited in this embodiment.
Reference to a battery in accordance with an embodiment 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, or the like. The battery generally includes a case for enclosing one or more battery cells or a plurality of battery modules. The case body can prevent liquid or other foreign matters from affecting the charge or discharge of the battery cells.
The battery cell includes a case for accommodating the electrode assembly and the electrolyte, an electrode assembly, and the electrolyte. The electrode assembly consists of a positive electrode plate, a negative electrode plate and a separation film. The battery cell mainly relies on metal ions to move between the positive pole piece and the negative pole piece to work. The positive electrode plate comprises a positive electrode current collector and a positive electrode active material layer, wherein the positive electrode active material layer is coated on the surface of the positive electrode current collector, and the part of the positive electrode current collector which is not coated with the positive electrode active material layer is used as a positive electrode lug so as to realize electric energy input or output of the positive electrode plate through the positive electrode lug. Taking a lithium ion battery as an example, the material of the positive electrode current collector may be aluminum, and the positive electrode active material may be lithium cobaltate, lithium iron phosphate, ternary lithium, lithium manganate or the like. The negative electrode plate comprises a negative electrode current collector and a negative electrode active material layer, wherein the negative electrode active material layer is coated on the surface of the negative electrode current collector, and the part of the negative electrode current collector which is not coated with the negative electrode active material layer is used as a negative electrode tab so as to realize electric energy input or output of the negative electrode plate through the negative electrode tab. The material of the negative electrode current collector may be copper, and the negative electrode active material may be carbon, silicon, or the like. In order to ensure that the high current is passed without fusing, the number of positive electrode lugs is multiple and stacked together, and the number of negative electrode lugs is multiple and stacked together.
The material of the separator may be PP (polypropylene) or PE (polyethylene). In addition, the electrode assembly may be a roll-to-roll structure or a lamination structure, and embodiments of the present application are not limited thereto.
The battery has the outstanding advantages of high energy density, small environmental pollution, large power density, long service life, wide application range, small self-discharge coefficient and the like, and is an important component of the development of new energy sources at present. The battery cell is obtained by assembling an electrode assembly (bare cell) by a positive electrode plate, a negative electrode plate and a separation film in a winding or lamination mode, then loading the electrode assembly into a shell, then covering an end cover, and finally injecting electrolyte. However, with the continuous development of battery technology, higher demands are also being placed on the energy density, the service performance, and the like of batteries.
For a general electrode assembly, the electrode assembly is composed of two electrode sheets (positive electrode sheet and negative electrode sheet) having opposite polarities and a separator, and in general, the electrode sheets are composed of a current collector and an active material layer coated on the surface of the current collector.
The inventor finds that the current collector is usually made of metal conductive materials such as copper foil and aluminum foil, has higher density, has larger influence on the quality of the electrode assembly, has a planar sheet structure on both sides of the current collector in general, and needs to increase the thickness of the current collector if the strength of the current collector needs to be ensured, and has the advantages that the contact area between the active material layer of the pole piece and the current collector is small after the active material layer is coated on the current collector with the planar structure, the contact resistance is larger, the bonding strength is lower, and the active material layer has the risk of easy falling. The above problems result in a large capacity density and poor usability of the electrode assembly.
In order to solve the above technical problems, in the prior art, a rough conductive coating is disposed on the surface of a current collector by improving the current collector, so as to increase the contact area between the current collector and the active material layer. Although the current collector of the structure improves the bonding strength of the active material layer and reduces the contact resistance between the active material layer and the current collector, on one hand, the current collector of the structure has the risk that the conductive coating is easy to separate in the use process, so that the active material layer is easy to separate, the service life of the battery monomer is not facilitated to be improved, on the other hand, the thickness of the current collector is easy to increase, the occupied space of the current collector is large, the energy density of the battery monomer is not facilitated to be improved, the structural strength of the current collector cannot be effectively improved, the service performance of the battery monomer is further poor, and the production cost of the battery monomer is not facilitated to be reduced.
Based on the above-mentioned considerations, in order to solve the problems of short cycle life and poor usability of the battery cell, the inventors have conducted intensive studies and have devised a current collector including a body portion having two coating surfaces disposed opposite to each other in a thickness direction of the current collector, and a reinforcing protrusion protruding from at least one of the two coating surfaces.
In the pole piece with the current collector, the reinforcing protrusions are arranged on the coating surface of at least one side of the body part so as to increase the contact area between the active material layer of the pole piece and the current collector, thereby being beneficial to improving the bonding strength of the current collector and the active material layer on one hand, reducing the risk of falling off of the active material layer of the pole piece in the use process, being beneficial to reducing the contact resistance between the current collector and the active material layer on the other hand, and further effectively improving the cycle service life of the battery monomer.
In addition, the structural strength of the current collector can be further increased through the reinforcing protrusions, the minimum thickness requirement of the current collector is reduced, the structural strength of the current collector is ensured, meanwhile, the containing amount of the active material layer of the current collector with the structure can be effectively increased in the pole piece with the same overall thickness, the storage capacity of the pole piece to electrolyte can be improved, and therefore the energy density and the service performance of a battery monomer are improved.
The current collector disclosed by the embodiment of the application can be used in electric devices such as vehicles, ships or aircrafts, but is not limited to the electric devices. The power supply system with the pole piece, the electrode assembly, the battery monomer and the like which are disclosed by the application can be used for forming the power utilization device, so that the service performance and the service life of the battery monomer can be effectively improved, and the manufacturing cost of the battery monomer is reduced.
The embodiment of the application provides an electric device using a battery as a power supply, wherein the electric device can be, but is not limited to, a mobile phone, a tablet, a notebook computer, an electric toy, an electric tool, a battery car, an electric car, a ship, a spacecraft and the like. Among them, the electric toy may include fixed or mobile electric toys, such as game machines, electric car toys, electric ship toys, electric plane toys, and the like, and the spacecraft may include planes, rockets, space planes, and spacecraft, and the like.
For convenience of description, the following embodiment will take an electric 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, the controller 200 being configured to control the battery 100 to power the motor 300, for example, 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 assembly space for the battery cells 20, and the case 10 may have various structures. In some embodiments, the case 10 may include a first case body 11 and a second case body 12, the first case body 11 and the second case body 12 being covered with each other, the first case body 11 and the second case body 12 together defining an assembly space for accommodating the battery cell 20. The second box body 12 may have a hollow structure with one end opened, the first box body 11 may have a plate-shaped structure, and the first box body 11 covers the open side of the second box body 12, so that the first box body 11 and the second box body 12 define an assembly space together; the first tank body 11 and the second tank body 12 may each have a hollow structure with one side opened, and the open side of the first tank body 11 may be closed to the open side of the second tank body 12. Of course, the case 10 formed by the first case body 11 and the second case body 12 may be various shapes, such as a cylinder, a rectangular parallelepiped, and 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.
Wherein each battery cell 20 may be a secondary battery or a primary battery; but not limited to, lithium sulfur batteries, sodium ion batteries, or magnesium ion batteries. The battery cell 20 may be in the shape of a cylinder, a flat body, a rectangular parallelepiped, or other shapes, etc. Illustratively, in fig. 2, the battery cell 20 is of a rectangular parallelepiped structure.
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 includes a case 21 and an electrode assembly 22, and the case 21 serves to accommodate the electrode assembly 22.
Wherein the housing 21 may also be used to contain an electrolyte, such as an electrolyte solution. The housing 21 may take a variety of structural forms.
In some embodiments, the case 21 may include a case 211 and an end cap 212, the case 211 being a hollow structure having one side opening 2111, the end cap 212 for covering at the opening 2111 of the case 211 and forming a sealing connection to form a sealed space for accommodating the electrode assembly 22 and the electrolyte.
In assembling the battery cell 20, the electrode assembly 22 may be placed in the case 211, the case 211 may be filled with an electrolyte, and then the end cap 212 may be covered on the opening 2111 of the case 211.
The housing 211 may be of various shapes, such as a cylinder, a rectangular parallelepiped, etc. The shape of the case 211 may be determined according to the specific shape of the electrode assembly 22. For example, if the electrode assembly 22 is a cylindrical structure, a cylindrical housing may be selected; if the electrode assembly 22 is of a rectangular parallelepiped configuration, a rectangular parallelepiped housing may be selected. Of course, the end cap 212 may have various structures, for example, the end cap 212 has a plate-like structure, a hollow structure with one end opening 2111, and the like. Illustratively, in fig. 3, the electrode assembly 22 has a rectangular parallelepiped structure, and the case 211 has a rectangular parallelepiped structure, the end cap 212 has a rectangular plate-like structure, and the end cap 212 is covered at the opening 2111 of the case 211.
In some embodiments, the battery cell 20 may further include a positive electrode terminal 23, a negative electrode terminal 24, and a pressure relief mechanism 25, each of the positive electrode terminal 23, the negative electrode terminal 24, and the pressure relief mechanism 25 being mounted on the end cap 212. The positive electrode terminal 23 and the negative electrode terminal 24 are each used to be electrically connected with the electrode assembly 22 to achieve input and output of electric power of the battery cell 20. The pressure release mechanism 25 is used to release the pressure inside the battery cell 20 when the internal pressure or temperature of the battery cell 20 reaches a predetermined value.
Illustratively, as shown in fig. 3, a pressure relief mechanism 25 is located between the positive electrode terminal 23 and the negative electrode terminal 24. The pressure relief mechanism 25 may be a component such as an explosion proof valve, an explosion proof disc, a gas valve, a pressure relief valve, or a safety valve.
It is to be understood that the case 21 is not limited to the above-described structure, and the case 21 may be other structures, for example, the case 21 may include a case 211 and two end caps 212, the case 211 being a hollow structure having opposite side openings 2111, and one end cap 212 being correspondingly covered at one opening 2111 of the case 211 and forming a sealing connection to form a sealed space for accommodating the electrode assembly 22 and the electrolyte. In this structure, the positive electrode terminal 23 and the negative electrode terminal 24 may be mounted on the same end cap 212, or may be mounted on different end caps 212; the pressure release mechanism 25 may be mounted on one end cap 212, or the pressure release mechanisms 25 may be mounted on both end caps 212.
In the embodiment of the present application, the electrode assembly 22 accommodated in the case 21 may be one or more. Illustratively, in fig. 3, the electrode assemblies 22 are two, with two electrode assemblies 22 being arranged in a stack.
The electrode assembly 22 is a member in which electrochemical reactions occur in the battery cell 20. Referring to fig. 4, fig. 4 is a cross-sectional view of an electrode assembly 22 according to some embodiments of the present application. The electrode assembly 22 may include a electrode sheet 221 and a separator 222, the electrode sheet 221 being disposed to be overlapped with the separator 222. The electrode assembly 22 may be a wound structure formed by winding the electrode sheet 221 and the separator 222, or a laminated structure formed by laminating the electrode sheet 221 and the separator 222. Illustratively, in fig. 4, the electrode assembly 22 is a wound structure formed by winding a pole piece 221 and a separator 222. The electrode assembly 22 includes two electrode plates 221 (positive electrode plate and negative electrode plate) with opposite polarities, the two electrode plates 221 (positive electrode plate and negative electrode plate) with opposite polarities and a separator 222 wound around each other, the separator 222 is disposed between the two electrode plates 221 (positive electrode plate and negative electrode plate) with opposite polarities, and the separator 222 is used for separating the two electrode plates 221 (positive electrode plate and negative electrode plate) with opposite polarities.
Referring to fig. 5, fig. 5 is a schematic partial structure of a pole piece 221 according to some embodiments of the application. The electrode sheet 221 includes a current collector 2211 and an active material layer 2212, and the active material layer 2212 is provided on both sides of the current collector 2211 in the thickness direction of the current collector 2211. Of course, in some embodiments, the electrode sheet 221 may also be configured, for example, in the thickness direction of the current collector 2211, with the active material layer 2212 disposed only on one side of the current collector 2211.
Referring to fig. 4 and 5, and further referring to fig. 6 and 7, fig. 6 is a top view of a current collector 2211 according to some embodiments of the present application, that is, a view of the current collector 2211 in its thickness direction, and fig. 7 is a partial cross-sectional view of the current collector 2211 according to some embodiments of the present application. The present application provides a current collector 2211, the current collector 2211 including a body portion 2211a and a reinforcing protrusion 2211b. The body portion 2211a has two coating surfaces 2211c disposed opposite to each other in the thickness direction X of the current collector. The reinforcing protrusion 2211b protrudes from at least one coated surface 2211c of the two coated surfaces 2211c.
Wherein the body portion 2211a has coating surfaces 2211c on both sides in the thickness direction X of the current collector, the coating surfaces 2211c being used for coating an active material to form active material layers 2212 on both sides of the body portion 2211 a. It should be noted that the coating surface 2211c is used for coating the active material, and the coating surface 2211c is provided with the reinforcing protrusion 2211b protruding thereon, and coating the active material on the coating surface 2211c means coating the active material on the side of the body portion 2211a having the coating surface 2211c to form the active material layer 2212 on the side of the current collector 2211 so that the active material can be covered on the coating surface 2211c and the reinforcing protrusion 2211b is accommodated in the active material layer 2212.
Illustratively, in fig. 6, the coating surface 2211c is provided with a plurality of reinforcing protrusions 2211b, and the reinforcing protrusions 2211b are in a bar-like structure extending along a straight line. Of course, in some embodiments, the reinforcing protrusion 2211b may also be a cylindrical protrusion or a wavy strip structure, etc.
Illustratively, in fig. 7, two coated surfaces 2211c on both sides of the body portion 2211a are provided with reinforcing protrusions 2211b. Of course, in other embodiments, the reinforcing protrusion 2211b may be provided only on the coating surface 2211c of one side of the body portion 2211 a.
Note that, the current collector 2211 may be used for a positive electrode tab or a negative electrode tab. The body portion 2211a and the reinforcing protrusion 2211b are integrally formed, and the current collector 2211 may be made of various materials, for example, the current collector 2211 may be made of copper, nickel or aluminum. When the current collector 2211 is made of copper, the current collector 2211 may be used for a negative electrode tab, and the current collector 2211 may be manufactured by electrolysis or corrosion, etc. to form a reinforcing protrusion 2211b on one side of the body portion 2211 a; when the current collector 2211 is made of aluminum, the current collector 2211 may be used for a positive electrode sheet, and the current collector 2211 may be manufactured by electrolysis or corrosion, etc., however, since the current collector 2211 made of aluminum has a softer texture, the current collector 2211 may also be manufactured by rolling or stamping, etc. to form a reinforcing protrusion 2211b on one side of the body portion 2211 a. That is, the current collector 2211 is formed with the reinforcing protrusion 2211b at least one side in the thickness direction thereof, and the reinforcing protrusion 2211b may be a protrusion structure formed at one side of the current collector 2211 to form the reinforcing protrusion 2211b, or a groove may be provided at one side of the current collector 2211 to form the reinforcing protrusion 2211b.
By providing the reinforcing protrusions 2211b on the coating surface 2211c on at least one side of the body portion 2211a, that is, the side of the current collector 2211 for coating the active material layer 2212 is formed with the concave-convex structure, so that in the electrode sheet 221 having such a structure of the current collector 2211, the contact area between the active material layer 2212 of the electrode sheet 221 and the current collector 2211 can be increased, thereby being beneficial to improving the adhesive strength of the current collector 2211 and the active material layer 2212 on the one hand, reducing the risk of falling of the active material layer 2212 of the electrode sheet 221 during use, and being beneficial to reducing the contact resistance between the current collector 2211 and the active material layer 2212 on the other hand, and further being capable of effectively improving the cycle life of the battery cell 20. In addition, the structural strength of the current collector 2211 itself can be increased by reinforcing the protrusions 2211b, the minimum thickness requirement of the current collector 2211 is reduced, so that the capacity of the active material layer 2212 can be effectively increased for the electrode sheet 221 of the current collector 2211 having such a structure in the electrode sheet 221 having the same overall thickness while the structural strength of the current collector 2211 is ensured, and the storage capacity of the electrode sheet 221 for the electrolyte can be improved, thereby being beneficial to improving the energy density and the service performance of the battery cell 20.
According to some embodiments of the present application, as shown in fig. 7, the maximum dimension of the current collector 2211 is D along the thickness direction X of the current collector 1 The body portion 2211a has a minimum thickness D 2 Satisfy D 1 -D 2 ≥0.5μm。
Wherein the maximum dimension of the current collector 2211 is D 1 I.e. in the thickness direction X of the current collector, the current collector 2211 occupies a maximum thickness D 1 The method comprises the steps of carrying out a first treatment on the surface of the The minimum thickness of the body portion 2211a is D 2 I.e., the minimum thickness of the body portion 2211a in the thickness direction X of the current collector.
By setting the difference between the maximum dimension of the current collector 2211 in the thickness direction thereof and the minimum thickness of the body portion 2211a to be greater than 0.5 μm to secure the dimension of the reinforcing protrusion 2211b protruding from the coated surface 2211c of the body portion 2211a, it is possible to alleviate the phenomenon that the structural strength of the current collector 2211 is not achieved due to the insufficient dimension of the reinforcing protrusion 2211 b.
According to one of the applicationIn some embodiments, the current collector 2211 has an equivalent thickness D 3 Satisfies that D is less than or equal to 1 mu m 3 And is less than or equal to 20 mu m. Wherein D is 3 ＝m/(ρ×S 1 ) The mass of the current collector 2211 is m, the density of the current collector 2211 is ρ, and the area of the coated surface 2211c is S 1 。
The area of the coating surface 2211c is the area of the projection area of the body portion 2211a in the thickness direction X of the current collector.
Wherein the equivalent thickness of the current collector 2211 is the whole mass m of the current collector 2211 divided by the actual density ρ of the current collector 2211 and the surface area S of the body portion 2211a side 1 That is, the equivalent thickness of the current collector 2211 is S, which is the area of the single side formed by remelting the current collector 2211 1 Such that in the case of the current collector 2211 having a partially thickened region and a partially thinned region in its thickness, i.e., the minimum thickness of the current collector 2211 is smaller than the thickness of the planar current collector, and the maximum thickness of the current collector 2211 is larger than the thickness of the planar current collector, compared to the planar current collector structure in the prior art, the current collector 2211 having a smaller equivalent thickness and having a concave-convex structure formed at least on one side is finally obtained.
By setting the equivalent thickness of the current collector 2211 to 1 μm to 20 μm, that is, in the pole piece 221 of the same thickness, the current collector 2211 of such a structure has a smaller equivalent thickness, so that there is more space for accommodating the active material layer 2212 at the side where the reinforcing protrusion 2211b is provided, thereby being capable of accommodating more active material layers 2212, and further being capable of effectively improving the accommodating amount of the active material layer 2212 of the pole piece 221 while ensuring the structural strength of the current collector 2211, it is advantageous to improve the energy density of the pole piece 221 having such a current collector 2211.
According to some embodiments of the present application, referring to fig. 7, the thickness D of the body portion 2211a is shown as 4 Satisfies D of 0.5 μm 4 ≤10μm。
Wherein, the thickness D of the body portion 2211a 4 Is the average thickness of the body portion 2211 a.
By setting the thickness of the body portion 2211a to 0.5 μm to 10 μm, on the one hand, the risk of breakage of the current collector 2211 during use due to the too small thickness of the body portion 2211a can be reduced, and on the other hand, the phenomena of excessive space occupation and excessive weight occupation of the current collector 2211 due to the too large thickness of the body portion 2211a can be reduced.
According to some embodiments of the present application, referring to fig. 7, the area of the end surface of the reinforcing protrusion 2211b facing away from the end of the body portion 2211a in the thickness direction X of the current collector is S 2 The area of the coated surface 2211c is S 1 Meets the requirements of 0.1 to less than or equal to (S) 2 ×n)/S 1 Less than or equal to 0.9; where n is the number of reinforcing protrusions 2211b on the coated surface 2211 c.
Wherein the reinforcing protrusion 2211b is connected to the body portion 2211a at one end in the thickness direction X of the current collector, and the area of the end face at the other end is S 1 N is the number of the reinforcing protrusions 2211b provided on the coated surface 2211c on one side of the body portion 2211a, that is, the total area of the end surfaces of the reinforcing protrusions 2211b facing away from the one end of the body portion 2211a accounts for 10% to 90% of the area of one coated surface 2211 c.
The area of the coating surface 2211c is the area of the projection area of the body portion 2211a in the thickness direction X of the current collector.
By setting the ratio of the total area of the end surface of the reinforcing protrusion 2211b remote from the one end of the body portion 2211a to the area of the coated surface 2211c of the body portion 2211a to 0.1 to 0.9, it is possible to reduce the risk of the adhesive strength between the current collector 2211 and the active material layer 2212 being low and the contact area being insufficient due to the total area of the end surface of the reinforcing protrusion 2211b occupying the coated surface 2211c being too small, on the one hand, and to alleviate the phenomenon of the space for accommodating the active material layer 2212 being too small due to the total area of the end surface of the reinforcing protrusion 2211b occupying the coated surface 2211c being too large, on the other hand, thereby contributing to ensuring the amount of accommodation of the active material layer 2212 by the current collector 2211.
According to some embodiments of the present application, referring to fig. 6 and 7, the reinforcement protrusion 2211b is a bar-shaped structure extending along a straight track, and the extension direction of the reinforcement protrusion 2211b is perpendicular to the thickness direction X of the current collector.
Here, the reinforcing protrusion 2211b is a bar-shaped structure extending along a straight line track, that is, the reinforcing protrusion 2211b is a linear bar-shaped protrusion, and the extending direction of the reinforcing protrusion 2211b is perpendicular to the thickness direction X of the current collector, that is, the extending direction of the reinforcing protrusion 2211b is parallel to the coating surface 2211c of the body portion 2211a, and the reinforcing protrusion 2211b may extend in the length direction Y of the current collector or may extend in the width direction Z of the current collector, and illustratively, in fig. 6, the extending direction of the reinforcing protrusion 2211b is the length direction Y of the current collector, that is, the length direction of the body portion 2211 a. Of course, in other embodiments, referring to fig. 8, fig. 8 is a top view of a current collector 2211 according to still other embodiments of the present application, and the extending direction of the reinforcing protrusion 2211b may also be disposed at an angle with respect to the length direction Y of the current collector.
Illustratively, in fig. 7, the reinforcing protrusion 2211b has a strip-shaped structure with a rectangular cross section, and in other embodiments, the cross section of the reinforcing protrusion 2211b may have various shapes, for example, in fig. 9 and 10, fig. 9 is a top view of the current collector 2211 provided in still other embodiments of the present application, fig. 10 is a partial cross section of the current collector 2211 provided in still other embodiments of the present application, the cross section of the reinforcing protrusion 2211b may have a trapezoid structure, and the larger area end of the reinforcing protrusion 2211b is connected to the body portion 2211a.
By providing the reinforcing protrusions 2211b in a bar-like structure with the reinforcing protrusions 2211b extending in a direction perpendicular to the thickness direction X of the current collector, the reinforcing protrusions 2211b of such a structure contribute to the improvement of the mechanical strength and the structural strength of the current collector 2211.
According to some embodiments of the present application, the elongation at break of current collector 2211 is e, satisfying 1.1% and less than or equal to e and less than or equal to 8%.
Wherein, the elongation at break of the current collector 2211 is e, which means that when the current collector 2211 is broken by an external force, the ratio of the elongation of the current collector 2211 before and after stretching to the elongation before stretching is called elongation at break.
For example, the method of measuring the breaking elongation of the current collector 2211 may be measuring using a stretcher having a first chuck and a second chuck arranged at intervals. Firstly, the current collector 2211 is cut into a rectangular block structure with a preset size, then the two ends of the cut current collector 2211 in the length direction are respectively clamped by a first chuck and a second chuck, then the current collector 2211 is stretched at a constant speed by the first chuck and the second chuck, and the stretcher is stopped when the current collector 2211 is broken. At this time, the stretched length of the current collector 2211 is measured, and the stretched length of the current collector 2211 is divided by the distance between the first chuck and the second chuck to obtain the breaking elongation rate of the current collector 2211.
The breaking elongation of the current collector 2211 is set to be 1.1-8% so as to ensure the mechanical strength of the current collector 2211, thereby reducing the phenomenon that the current collector 2211 is broken or damaged in the use process and being beneficial to prolonging the service life of the current collector 2211.
According to some embodiments of the present application, referring to fig. 6 and 7, the coated surface 2211c is provided with a plurality of reinforcing protrusions 2211b.
Illustratively, in fig. 6, a plurality of reinforcing protrusions 2211b are arranged at intervals in the width direction Z of the current collector. The plurality of reinforcing protrusions 2211b may be arranged in various manners, for example, the plurality of reinforcing protrusions 2211b may be arranged at intervals along the length direction Y of the current collector, or may be arranged at intervals along a direction forming an included angle with the length direction Y of the current collector. Of course, the arrangement of the plurality of reinforcing protrusions 2211b is not limited thereto, and in some embodiments, referring to fig. 11, fig. 11 is a top view of a current collector 2211 according to other embodiments of the present application, the plurality of reinforcing protrusions 2211b may also be arranged to intersect with each other, so that the plurality of reinforcing protrusions 2211b form a grid-like structure.
By providing the plurality of reinforcing protrusions 2211b on the coating surface 2211c of the body portion 2211a, on the one hand, the structural strength of the current collector 2211 can be further improved, the service life of the current collector 2211 can be advantageously improved, on the other hand, the contact area between the current collector 2211 and the active material layer 2212 can be further improved, the contact resistance between the current collector 2211 and the active material layer 2212 can be advantageously reduced, and the connection stability between the current collector 2211 and the active material layer 2212 can be advantageously improved.
According to some embodiments of the present application, both coated surfaces 2211c are provided with protruding stiffening protrusions 2211b, see fig. 7.
Wherein both coating surfaces 2211c are convexly provided with reinforcing protrusions 2211b, i.e., both sides of the current collector 2211 in the thickness direction thereof are provided with reinforcing protrusions 2211b, thereby forming the current collector 2211 having a concave-convex structure on both sides.
Alternatively, the reinforcing protrusions 2211b provided at both sides of the body portion 2211a in the thickness direction X of the current collector may be symmetrically arranged or asymmetrically arranged. Illustratively, in fig. 7, the reinforcing protrusions 2211b provided on both sides of the body portion 2211a in the thickness direction X of the current collector are symmetrically arranged on both sides of the body portion 2211 a. Of course, in other embodiments, referring to fig. 12, fig. 12 is a cross-sectional view of a current collector 2211 according to some embodiments of the present application, and reinforcing protrusions 2211b disposed on both sides of a body portion 2211a along a thickness direction X of the current collector are disposed on both sides of the body portion 2211a in a staggered manner, thereby forming an asymmetrically disposed structure.
By providing the reinforcing protrusions 2211b on both the coating surfaces 2211c of the body portion 2211a, that is, the reinforcing protrusions 2211b are protruded on both sides of the body portion 2211a in the thickness direction X of the current collector, on the one hand, it is advantageous to further increase the overall structural strength of the current collector 2211, on the other hand, the contact area of both sides of the current collector 2211 with the active material layer 2212 can be increased, and the accommodation amount of the active material layer 2212 on both sides of the current collector 2211 can be increased, thereby being advantageous to increase the overall use performance of the pole piece 221 of the current collector 2211 having such a structure.
According to some embodiments of the present application, there is also provided a pole piece 221 including an active material layer 2212 and the current collector 2211 of any of the above embodiments, the active material layer 2212 being coated on the coated surface 2211c of the body portion 2211 a.
It should be noted that, the electrode piece 221 may be a positive electrode piece or a negative electrode piece, and the embodiment of the present application is not limited herein.
The pole piece 221 with the structure can effectively increase the contact area between the current collector 2211 and the active material layer 2212 on one hand, thereby being beneficial to improving the bonding strength and the connection stability of the current collector 2211 and the active material layer 2212, reducing the contact resistance between the current collector 2211 and the active material layer 2212, effectively increasing the containing amount of the active material layer 2212 of the pole piece 221 on the other hand, improving the preservation capacity of the pole piece 221 to electrolyte, and improving the energy density of the pole piece 221, thereby improving the service performance of the pole piece 221.
According to some embodiments of the application, the body portion 2211a has a weakened area, and the active material layer 2212 covers the weakened area.
After the active material layer 2212 is disposed on the current collector 2211, the particles of the active material layer 2212 can be pressed against the body portion 2211a by the cold pressure of the active material layer 2212, so that the particles of the active material layer 2212 can cause a certain damage or damage to the body portion 2211a, thereby forming a weak area on the body portion 2211a, and the weak area can accommodate a portion of the active material layer 2212, that is, a portion of the particles of the active material layer 2212.
Illustratively, the weakened area formed on the body portion 2211a may be a crack or a groove, that is, when the active material layer 2212 is cold-pressed, a portion of the particles of the active material layer 2212 can press the body portion 2211a and form the crack or groove, so that the crack or groove can accommodate a portion of the particles of the active material layer 2212, that is, the weakened area formed on the body portion 2211 a. Of course, in some embodiments, grooves, slits, or the like may be formed in the body portion 2211a of the current collector 2211 as a weakened area before the active material layer 2212 is coated on the current collector 2211, and then the active material layer 2212 may be coated.
By arranging the weak area on the body portion 2211a and covering the active material layer 2212 on the weak area, the weak area can play a certain role in preserving electrolyte, and further the preserving capability of the pole piece 221 on the electrolyte is improved, so that the usability of the pole piece 221 is improved.
According to some embodiments of the present application, there is also provided an electrode assembly 22 including the pole piece 221 of any of the above aspects.
According to some embodiments of the present application, there is also provided a battery cell 20 including a case 21 and the electrode assembly 22 of any of the above aspects, the electrode assembly 22 being accommodated in the case 21.
According to some embodiments of the present application, there is further provided a battery 100 including a plurality of battery cells 20 according to any one of the above aspects, wherein the plurality of battery cells 20 are connected in series or parallel with each other.
According to some embodiments of the present application, there is further provided an electric device including the battery 100 of any of the above aspects, and the battery 100 is used to provide electric energy to the electric device.
The powered device may be any of the devices or systems described above that employ battery 100.
According to some embodiments of the present application, referring to fig. 5 to 7, the present application provides a current collector 2211, the current collector 2211 including a body portion 2211a and a reinforcing protrusion 2211b. The body portion 2211a has two coating surfaces 2211c disposed opposite to each other in the thickness direction X of the current collector. A plurality of reinforcing protrusions 2211b are convexly provided on each of the two coating surfaces 2211c, the reinforcing protrusions 2211b are in a bar-like structure extending along a straight line track, and the extending direction of the reinforcing protrusions 2211b is perpendicular to the thickness direction X of the current collector. Wherein, the thickness of the body portion 2211a is D 4 Satisfies D of 0.5 μm 4 Less than or equal to 10 mu m, and the equivalent thickness of the current collector 2211 is D 3 Satisfies that D is less than or equal to 1 mu m 3 ≤20μm，D 3 ＝m/(ρ×S 1 ) The mass of the current collector 2211 is m, the density of the current collector 2211 is ρ, and the area of the coated surface 2211c is S 1 。
The embodiment of the present application further provides a method for manufacturing the pole piece 221, please refer to fig. 13, fig. 13 is a flow chart of the method for manufacturing the pole piece 221 according to some embodiments of the present application, the method includes:
s100: providing a current collector 2211, the current collector 2211 comprising a body portion 2211a and a reinforcing protrusion 2211b, the body portion 2211a having two coating surfaces 2211c arranged opposite to each other in a thickness direction X of the current collector, the reinforcing protrusion 2211b protruding from at least one coating surface 2211c of the two coating surfaces 2211c;
s200: an active material layer 2212 is coated on the coated surface 2211 c.
It should be noted that, the related structure of the pole piece 221 manufactured by the manufacturing method provided by the foregoing embodiments may be referred to the pole piece 221 provided by the foregoing embodiments, and will not be described herein again.
Referring to fig. 13, in step S200: after the active material layer 2212 is coated on the coated surface 2211c, the manufacturing method of the pole piece 221 further includes:
s300: the active material layer 2212 is cold pressed to press a portion of the active material layer 2212 into the body portion 2211a, and the body portion 2211a forms a weakened area at a position pressed by the portion of the active material layer 2212.
Wherein, after cold pressing the active material layer 2212 coated on the coating surface 2211c of the body portion 2211a, it is possible to achieve that the particles of the active material layer 2212 press the coating surface 2211c of the body portion 2211a, so that the particles of the active material layer 2212 can cause a certain breakage or damage to the body portion 2211a, thereby enabling the formation of a weak area on the body portion 2211 a. The body portion 2211a forms a weakened area at a position pressed by the portion of the active material layer 2212, that is, the weakened area formed by the damaged area of the body portion 2211a can accommodate a portion of the active material layer 2212, that is, a portion of the particles of the active material layer 2212.
Illustratively, the weakened area formed on the body portion 2211a may be a crack or a groove, that is, when the active material layer 2212 is cold-pressed, a portion of the particles of the active material layer 2212 can press the body portion 2211a and form the crack or groove, so that the crack or groove can accommodate a portion of the particles of the active material layer 2212, that is, the weakened area formed on the body portion 2211 a.
By cold pressing the active material layer 2212 disposed on the coating surface 2211c, part of particles of the active material layer 2212 can be pressed into the body portion 2211a to form a weak area on the body portion 2211a, and the weak area can play a certain role in preserving the electrolyte, so that the preserving capability of the pole piece 221 on the electrolyte is improved.
It should be noted that, without conflict, the embodiments of the present application and features of the embodiments may be combined with each other.
The above is only a preferred embodiment of the present application, and is not intended to limit the present application, but various modifications and variations can be made to the present application by those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included in the protection scope of the present application.

Claims (17)

1. A current collector, comprising:
a body portion having two coating surfaces disposed opposite to each other in a thickness direction of the current collector; and
and the reinforcing protrusion is arranged on at least one of the two coating surfaces in a protruding mode.
2. The current collector of claim 1, wherein the maximum dimension of the current collector in the thickness direction of the current collector is D 1 The minimum thickness of the body part is D 2 Satisfy D 1 -D 2 ≥0.5μm。
3. The current collector of claim 1, wherein the current collector has an equivalent thickness D 3 Satisfies that D is less than or equal to 1 mu m 3 ≤20μm；
Wherein D is 3 ＝m/(ρ×S 1 ) The mass of the current collector is m, the density of the current collector is ρ, and the area of the coating surface is S 1 。
4. The current collector of claim 1, wherein the thickness of the body portion is D 4 Satisfies D of 0.5 μm 4 ≤10μm。
5. The current collector according to claim 1, wherein in a thickness direction of the current collector, theThe area of the end face of the end of the reinforcing protrusion, which is away from the body part, is S 2 The area of the coating surface is S 1 Meets the requirements of 0.1 to less than or equal to (S) 2 ×n)/S 1 ≤0.9；
Wherein n is the number of the reinforcing protrusions on the coated surface.
6. The current collector of claim 1, wherein the reinforcing protrusions are in a bar-like structure extending along a straight line locus, and the extending direction of the reinforcing protrusions is perpendicular to the thickness direction of the current collector.
7. The current collector of claim 1, wherein the elongation at break of the current collector is e, satisfying 1.1% or less and 8% or less.
8. The current collector of claim 1, wherein said coated surface is convexly provided with a plurality of said reinforcing protrusions.
9. A current collector according to any one of claims 1-8, wherein both of said coated surfaces are convexly provided with said reinforcing protrusions.
10. A pole piece, comprising:
a current collector according to any one of claims 1-9; and
An active material layer coated on the coated surface.
11. A pole piece according to claim 10, characterized in that the body part has a weakened area, the active substance layer covering the weakened area.
12. An electrode assembly comprising a pole piece according to claim 10 or 11.
13. A battery cell, comprising:
a housing; and
the electrode assembly of claim 12, housed within the housing.
14. A battery comprising a plurality of cells according to claim 13.
15. An electrical device comprising a battery according to claim 14.
16. A method of manufacturing a pole piece, comprising:
providing a current collector, wherein the current collector comprises a body part and a reinforcing protrusion, the body part is provided with two coating surfaces which are oppositely arranged along the thickness direction of the current collector, and the reinforcing protrusion is convexly arranged on at least one of the two coating surfaces;
an active material layer is coated on the coated surface.
17. The method of manufacturing a pole piece of claim 16, wherein after said applying an active material layer to said coated surface, the method further comprises:
Cold pressing the active material layer to press a portion of the active material layer into the body portion, the body portion forming a weakened area at a location pressed by the portion of the active material layer.
CN202210551576.1A 2022-05-20 2022-05-20 Current collector, pole piece, electrode assembly, battery monomer, battery and power utilization device Pending CN117133928A (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
CN202210551576.1A CN117133928A (en) 2022-05-20 2022-05-20 Current collector, pole piece, electrode assembly, battery monomer, battery and power utilization device
PCT/CN2023/080133 WO2023221606A1 (en) 2022-05-20 2023-03-07 Current collector, electrode sheet, electrode assembly, battery cell, battery and electric apparatus

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202210551576.1A CN117133928A (en) 2022-05-20 2022-05-20 Current collector, pole piece, electrode assembly, battery monomer, battery and power utilization device

Publications (1)

Publication Number Publication Date
CN117133928A true CN117133928A (en) 2023-11-28

Family

ID=88834522

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202210551576.1A Pending CN117133928A (en) 2022-05-20 2022-05-20 Current collector, pole piece, electrode assembly, battery monomer, battery and power utilization device

Country Status (2)

Country Link
CN (1) CN117133928A (en)
WO (1) WO2023221606A1 (en)

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP5492686B2 (en) * 2010-07-07 2014-05-14 大日本スクリーン製造株式会社 Battery electrode manufacturing method, battery manufacturing method, battery, vehicle, and electronic device
CN207303231U (en) * 2017-08-16 2018-05-01 青岛科技大学 A kind of graphene lithium-ion negative pole pole piece
CN207732007U (en) * 2017-10-23 2018-08-14 宁德新能源科技有限公司 Cathode pole piece and lithium ion battery
CN212485372U (en) * 2020-06-30 2021-02-05 上海卡耐新能源有限公司 Current collector, electrode plate and lithium ion battery

Also Published As

Publication number Publication date
WO2023221606A1 (en) 2023-11-23

Similar Documents

Publication Publication Date Title
CN112467231B (en) Electrode assembly, battery cell, battery, and method and apparatus for manufacturing electrode assembly
EP4131631A1 (en) Electrode assembly, battery cell, battery and power-consuming apparatus
US11757161B2 (en) Battery cell, battery and electricity consuming device
CN115803925B (en) Electrode assembly, battery cell, battery, and apparatus and method for manufacturing electrode assembly
CN216213945U (en) Battery cell, battery and power consumption device
CN217158476U (en) Shell, battery monomer, battery and consumer
CN216389634U (en) Battery and electric equipment
CN215266587U (en) Current collecting member, battery cell, battery, and power consumption device
CN115413379B (en) Electrode assembly, battery cell, battery, and method and apparatus for manufacturing electrode assembly
CN115606020B (en) Electrode assembly, manufacturing method and manufacturing system thereof, battery cell and battery
CN219626726U (en) Electrode assembly, battery cell, battery and electric equipment
CN116097488A (en) Electrode assembly, battery cell, battery, and method and apparatus for manufacturing electrode assembly
CN116666774A (en) Electrode assembly, battery cell, battery and electric equipment
CN218414634U (en) Pole piece, electrode subassembly, battery monomer, battery and consumer
CN217768702U (en) Battery cell, battery and power consumption device
CN217361642U (en) Electrode assembly, battery cell, battery and electric equipment
CN216213793U (en) Battery cell, battery and power consumption device
CN215299297U (en) Electrode assembly, battery cell, battery, and power consumption device
EP4102606A1 (en) Electrode assembly, battery cell, battery, and power-consuming device
CN115881887A (en) Electrode component, battery monomer, battery and power consumption device
CN117044023A (en) Battery monomer, battery and power consumption device
CN116470241A (en) Electrode assembly, battery cell, battery and electric equipment
CN117133928A (en) Current collector, pole piece, electrode assembly, battery monomer, battery and power utilization device
CN218414630U (en) Pole piece, electrode component, battery monomer, battery and power consumption device
CN219350608U (en) Pole piece, electrode assembly, battery monomer, battery and electric equipment

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination