CN116364852B - Battery pole piece, preparation method thereof, electrode assembly, battery and electricity utilization device - Google Patents
Battery pole piece, preparation method thereof, electrode assembly, battery and electricity utilization device Download PDFInfo
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- CN116364852B CN116364852B CN202310647920.1A CN202310647920A CN116364852B CN 116364852 B CN116364852 B CN 116364852B CN 202310647920 A CN202310647920 A CN 202310647920A CN 116364852 B CN116364852 B CN 116364852B
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- pole piece
- coating
- battery pole
- battery
- electrode assembly
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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
- H01M4/13—Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M10/00—Secondary cells; Manufacture thereof
- H01M10/05—Accumulators with non-aqueous electrolyte
- H01M10/052—Li-accumulators
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M10/00—Secondary cells; Manufacture thereof
- H01M10/05—Accumulators with non-aqueous electrolyte
- H01M10/058—Construction or manufacture
- H01M10/0587—Construction or manufacture of accumulators having only wound construction elements, i.e. wound positive electrodes, wound negative electrodes and wound separators
-
- 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
-
- 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
- H01M4/13—Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
- H01M4/139—Processes of manufacture
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M2220/00—Batteries for particular applications
- H01M2220/20—Batteries in motive systems, e.g. vehicle, ship, plane
-
- 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)
- Engineering & Computer Science (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Electrochemistry (AREA)
- General Chemical & Material Sciences (AREA)
- Manufacturing & Machinery (AREA)
- Materials Engineering (AREA)
- Secondary Cells (AREA)
Abstract
The application discloses a battery pole piece, a preparation method thereof, an electrode assembly, a battery and an electric device. The surface of the battery pole piece is provided with a first coating and a second coating which can relieve stress, wherein the first coating is arranged on the surface of one end part of the battery pole piece along the length direction, and the second coating is arranged on the surface of the other end part of the battery pole piece along the length direction. After the battery pole piece is wound into the electrode assembly from one end, the stress relief space can be provided based on the thickening effect of the first coating and the second coating, so that the innermost ring and the outermost ring of the electrode assembly are not easy to cause purple spots and lithium is not easy to be separated, and the coating can improve the electrolyte retention of the electrode assembly, particularly the inner ring of the electrode assembly. Therefore, after the battery pole piece provided by the embodiment of the application is used for winding into an electrode assembly, the cycle life of the battery pole piece can be prolonged.
Description
Technical Field
The application belongs to the technical field of batteries, and particularly relates to a battery pole piece, a preparation method thereof, an electrode assembly, a battery and an electric device.
Background
In recent years, new energy automobiles are vigorously developed, a battery driving system is a main factor influencing the performance and cost of the new energy automobiles, and a secondary battery is a preferred scheme of a power battery in the battery driving system of the current new energy automobiles due to the characteristics of high energy density, low memory effect, high working voltage and the like.
The power battery cell is generally formed by winding a positive electrode plate, a separation film and a negative electrode plate to prepare a bare cell, and finally forming a finished product through the procedures of packaging, liquid injection, formation, charging and the like. In the charge-discharge cycle process of the battery monomer, the pole piece in the electrode assembly is easy to expand, and large stress is easily formed on the innermost ring and the outermost ring, so that the phenomena of purple spots, lithium precipitation and the like are caused, the electrode assembly is invalid, and safety accidents are caused.
Disclosure of Invention
In view of the above problems, the present application provides a battery pole piece, a preparation method thereof, an electrode assembly, a battery and an electric device, and aims to solve the technical problem of how to improve the capability of the battery pole piece for relieving expansion stress.
In a first aspect, an embodiment of the present application provides a battery pole piece, where a first coating layer and a second coating layer capable of relieving stress are provided on a surface of one end portion of the battery pole piece in a length direction, and the first coating layer is provided on a surface of the other end portion of the battery pole piece in the length direction.
Through set up first coating and second coating on the surface of the both ends of battery pole piece, and first coating and second coating separate each other, such battery pole piece is from the end winding back of electrode subassembly, the most inner circle position of electrode subassembly and the most outer circle position all additionally have increased the coating, can provide stress relief space to the stress that electrode subassembly inflation produced based on the thickening effect of first coating and second coating, thereby make electrode subassembly most inner circle and most outer circle be difficult to cause the purple spot, also be difficult to the lithium-out, and the coating can increase electrode subassembly inner circle and outer lane interlayer spacing, be favorable to improving electrode subassembly especially the electrolyte volume of electrode subassembly inner circle. Therefore, the battery pole piece provided by the embodiment of the application can improve the cycle life of the battery pole piece after being wound into the electrode assembly along the end part.
In one embodiment, the first coating comprises a first substrate, a first flexible material, a first binder, and a lithium salt; and/or the number of the groups of groups,
the second coating comprises a second substrate, a second flexible material, and a second binder.
The substrate, the flexible material and the binder are used in the coating, so that the stress generated by cyclic expansion of the first coating and the second coating on the surface of the battery pole piece can be well relieved, and lithium salt is added in the first coating relative to the second coating, so that the first coating is wound to form the innermost ring of the electrode assembly, and a lithium ion source can be provided for the inner ring of the electrode assembly, and the dynamic performance of the electrode assembly can be further improved.
In one embodiment, the first coating comprises, based on 100% total weight of the first coating: 80-90% of a first base material, 1-5% of a first flexible material, 1-5% of a first binder and 1-5% of lithium salt; and/or the number of the groups of groups,
the second coating layer comprises, based on 100% of the total weight of the second coating layer: 80-90% of a second base material, 1-5% of a second flexible material and 1-5% of a second binder.
The first coating formed by the first base material, the first flexible material, the first binder and the lithium salt in the proportion can not only relieve the main normal stress generated by the inner ring due to the expansion of the electrode assembly, but also provide a sufficient lithium ion source for the inner ring of the electrode assembly. And the second coating formed by the second base material, the second flexible material and the second binder in the proportion can relieve the shearing stress generated by the outer ring mainly along the tangential direction due to the expansion of the electrode assembly.
In an embodiment, the first substrate comprises at least one of a first solid electrolyte material, a first adhesive material, and a first ceramic material; and/or the number of the groups of groups,
the second substrate includes at least one of a second solid electrolyte material, a second adhesive material, and a second ceramic material.
The solid electrolyte material, the adhesive material and the ceramic material are used as main base materials of the coating, have certain toughness and elasticity, and can provide stress relief for the coating.
In one embodiment, the first substrate is a first solid electrolyte material or a first ceramic material; and/or the number of the groups of groups,
the second base material is prepared from the following components in percentage by mass (2-2.5): (5-6): (2-2.5) a second solid electrolyte material, a second adhesive material and a second ceramic material.
Because the inner ring of the electrode assembly mainly generates normal stress along the normal direction, the outer ring mainly generates shear stress along the tangential direction, the solid electrolyte material and the ceramic material have relatively better toughness, and the adhesive material has relatively better elasticity; therefore, after the battery pole piece is wound into the electrode assembly from one end of the first coating, the first solid electrolyte material or the first ceramic material in the first coating of the inner ring can be used as a base material to better relieve the positive stress, and the second solid electrolyte material and the second ceramic material in the second coating of the outer ring have lower content and higher content proportion of the second adhesive material, so that the shearing stress can be better relieved.
In an embodiment, the first substrate comprises a first solid electrolyte material, a first adhesive material and a first ceramic material, and the sum of the mass of the first solid electrolyte material and the mass of the first ceramic material is 80% or more of the total mass of the first substrate; and/or the number of the groups of groups,
The second substrate comprises a second solid electrolyte material, a second adhesive material and a second ceramic material, and the second adhesive material accounts for 60% or more of the total mass of the second substrate.
The first substrate with the proportion enables the first coating layer positioned on the inner ring of the electrode assembly to better relieve the positive stress, and the second substrate with the proportion enables the second coating layer positioned on the outer ring to better relieve the shearing stress.
In one embodiment, one or more of the following (1) - (3) are satisfied:
(1) The first solid electrolyte material and the second solid electrolyte material independently comprise at least one of an organic polymer-based electrolyte, an oxide-based electrolyte, and a sulfide-based electrolyte;
(2) The first adhesive material and the second adhesive material independently comprise at least one of cellulose ester, vinyl polymer, polyester, polyether, polyamide and cyanoacrylate;
(3) The first ceramic material and the second ceramic material independently comprise at least one of an oxide ceramic, a nitride ceramic, a carbide ceramic, and a cermet.
Solid electrolyte materials, adhesive materials and ceramic materials of the above-mentioned types can provide good stress relief capability for the coating as a substrate for the core function of the coating.
In one embodiment, one or more of the following (1) - (3) are satisfied:
(1) The first flexible material and the second flexible material independently comprise at least one of a carbon-based material, a transition metal carbon/nitride two-dimensional nano layered material and a polymer fiber material;
(2) The first binder and the second binder independently comprise at least one of polyvinylidene fluoride binder, acrylonitrile binder, polyurethane binder, acrylic binder, styrene-butadiene rubber binder and polyvinylpyrrolidone binder;
(3) The lithium salt includes at least one of lithium perchlorate, lithium tetrafluoroborate, lithium hexafluoroarsenate, and lithium hexafluorophosphate.
The use of flexible materials of the above kind in the coating gives the coating good plasticity and softness against expansion stresses. The use of binders of the above kind in the coating makes it possible to make the coating material firm and less prone to fall off when the coating is subjected to expansion stresses. The use of lithium salts of the above-mentioned kind in the coating provides a good source of lithium ions.
In one embodiment, one or more of the following (1) - (4) are satisfied:
(1) The thickness of the first coating is 3-5 mu m;
(2) The thickness of the second coating is 3-5 mu m;
(3) The length of the first coating along the surface length direction of the battery pole piece is M1, the total length of the battery pole piece is L, the circumference of a winding needle for winding the battery pole piece is D, and D/2 is more than or equal to M1 and less than or equal to L/4;
(4) The length of the second coating along the surface length direction of the battery pole piece is M2, the total length of the battery pole piece is L, the circumference of a winding needle for winding the battery pole piece is D, and D is less than or equal to M2 and less than or equal to L/4.
The thickness and the length of the coating are selected, so that the battery pole piece can be wound into an electrode assembly to have a good expansion stress relieving space, and meanwhile, the electrolyte retention quantity of the electrode assembly, particularly the inner ring of the electrode assembly, is improved, and the cycle life of the electrode assembly can be well prolonged in the parameter range.
In one embodiment, the battery pole piece comprises a current collector and an electrode active layer combined with the current collector, wherein the first coating and the second coating are arranged on the surface of the electrode active layer, which is away from the current collector; alternatively, the current collector extends along the length of the battery pole piece, and a first coating or a second coating is arranged on the surface of the extended exposed current collector.
The electrode assemblies with different winding structures are adapted by selecting different positions of the first coating and the second coating in the battery pole piece.
In one embodiment, the battery pole piece is a positive pole piece or a negative pole piece.
The first coating and the second coating are arranged on the surface of the positive electrode plate or the negative electrode plate, so that the effect of providing an expansion stress relief space and improving the preservation amount of electrolyte can be achieved.
In a second aspect, an embodiment of the present application provides a method for preparing the battery pole piece, including the following steps:
preparing a first slurry and a second slurry;
and respectively coating the first slurry and the second slurry on the surfaces of one end part and the other end part of the battery pole piece, and drying to form a first coating and a second coating.
The prepared first sizing agent and the second sizing agent are directly coated on the surfaces of two end parts of the battery pole piece to form the first coating layer and the second coating layer, the preparation method is simple in process and easy for industrial production, and after the prepared battery pole piece is wound into an electrode assembly, the expansion stress can be well relieved, so that the electrode assembly is not easy to generate purple spots, lithium is not easy to separate out, and the electrolyte retention amount of the electrode assembly can be improved.
In a third aspect, an embodiment of the present application provides an electrode assembly, including an anode, a cathode, and a separator disposed between the anode and the cathode, where the anode, the separator, and the cathode are in a winding structure, and the anode and/or the cathode is a battery pole piece provided in the first aspect of the present application and/or a battery pole piece prepared by a preparation method provided in the second aspect of the present application.
In the electrode assembly with the winding structure, the positive electrode and/or the negative electrode are/is wound by the battery pole piece special for the embodiment of the application, so that the expansion stress of the electrode assembly can be well relieved, the electrode assembly is not easy to generate purple spots, lithium is not easy to be separated out, and the electrolyte retention amount of the electrode assembly can be improved, therefore, the electrode assembly provided by the embodiment of the application has good cycle life.
In one embodiment, the first coating layer on the surface of the battery pole piece is located on the inner ring of the winding structure, and the second coating layer is located on the outer ring of the winding structure.
The first coating formed by material formula selection matching is positioned on the inner ring of the winding structure, so that the normal stress mainly generated by the inner ring along the normal direction can be well relieved, and the second coating formed by material formula selection matching is positioned on the outer ring of the winding structure, so that the shear stress mainly generated by the outer ring along the tangential direction can be well relieved.
In a fourth aspect, embodiments of the present application provide a battery comprising the electrode assembly provided in the third aspect of the present application.
The electrode assembly provided by the third aspect of the application is used by a battery, and has good cycle life due to the arrangement of the coating, so that the battery has the characteristics of good safety and stable cycle performance in the charge and discharge processes.
In a fifth aspect, an embodiment of the present application provides an electrical device, where the electrical device includes a battery provided in the fourth aspect of the present application.
By adopting the battery provided by the fourth aspect of the embodiment of the application, the power utilization device has good cycle stability and long service life, and can work for a longer time.
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
Various other advantages and benefits will become apparent to those of ordinary skill in the art upon reading the following detailed description of the preferred embodiments. The drawings are only for purposes of illustrating the preferred embodiments and are not to be construed as limiting the application. Also, like reference numerals are used to designate like parts throughout the accompanying drawings. In the drawings:
FIG. 1 is a schematic view of a battery pole piece with a coating on one side of the battery pole piece according to an embodiment of the application;
FIG. 2 is a schematic view of a battery pole piece with two sides provided with a coating according to an embodiment of the present application;
FIG. 3 is a schematic view of another structure of a battery pole piece with coating on both sides according to an embodiment of the present application;
fig. 4 is a schematic flow chart of a preparation method of a battery pole piece according to an embodiment of the application;
FIG. 5 is a schematic diagram of a bare cell structure according to an embodiment of the present application;
fig. 6 is a schematic view showing a battery cell structure of an embodiment of a secondary battery according to the present application;
fig. 7 is a schematic exploded view of a battery cell of the secondary battery shown in fig. 6;
fig. 8 is a schematic structural view of a battery module according to an embodiment of the present application;
FIG. 9 is a schematic structural view of a battery pack according to an embodiment of the present application;
fig. 10 is an exploded view of the battery pack of fig. 9;
fig. 11 is a schematic diagram of an embodiment of an electric device including a secondary battery as a power source according to an embodiment of the present application.
Reference numerals illustrate:
10-battery pole pieces; 101-a current collector; 102-an electrode active layer;
21-a first coating; 22-a second coating;
30-battery cells; 31-a housing; 32-a top cap assembly; 33-electrode assembly; 331-a negative pole piece; 3311-inner ring of negative pole piece; 3312-outer ring of negative pole piece; 332-a positive electrode plate; 333-isolating membrane;
40-battery module; 50-battery pack; 51-upper box body; 52-lower box.
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. In the description of the embodiments of the present application, the meaning of "plurality" is two or more unless explicitly defined otherwise.
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 the embodiments of the present application, the term "plurality" means two or more (including two), and similarly, "plural sets" means two or more (including two), and "plural sheets" means two or more (including two). "at least one" means more than one (including one, two, three, etc.).
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 formed; 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.
With the increasing decrease of traditional energy resources, the development of new energy storage devices is becoming more and more important. Among them, the secondary battery has been attracting attention because of its high energy density, high theoretical capacity, good cycle stability and environmental protection characteristics. The secondary battery can be applied to energy storage power supply systems such as hydraulic power, firepower, wind power and solar power stations, and is widely applied to the field of electric vehicles such as electric bicycles, electric motorcycles, electric automobiles and the like. With the continuous expansion of the application field of secondary batteries which can be used as power batteries, the market demand of the secondary batteries is also continuously expanding, and meanwhile, the requirements on the safety performance, the charge and discharge performance and the like of the secondary batteries are also higher and higher.
The current preparation of the secondary battery bare cell is generally formed by winding, and the wound bare cell is mainly formed by winding a positive pole piece, a separation film and a negative pole piece. For example, the bare cell feeding sequence is an isolating film, a negative electrode plate and a positive electrode plate, the ending sequence is the positive electrode plate, the negative electrode plate and the isolating film, the winding core structure of the isolating film for separating the positive electrode plate and the negative electrode plate is completed by attaching ending gummed paper, and the formed bare cell is finally formed into an electrode assembly through the procedures of packaging, liquid injection, formation, charging and the like. The electrode assembly is generally easy to circularly expand in the circulation process, for example, a negative electrode active material (such as graphite) is easy to circularly expand in the charge and discharge process, and large stress is easily formed on the innermost ring and the outermost ring of a negative electrode pole piece in the electrode assembly, and the stress can cause the phenomena of purple spots, even serious lithium precipitation and the like on the innermost ring and the outermost ring of the negative electrode, so that the electrode assembly is invalid, and safety accidents are caused.
Based on the above consideration, in order to overcome the defects of the battery pole piece, the embodiment of the application designs a battery pole piece capable of relieving the stress of an electrode assembly caused by charge and discharge cycles, and particularly, a first coating and a second coating are arranged on the surfaces of two end parts of the battery pole piece. The expansion stress is relieved by utilizing the thickening effect of the materials of the first coating and the second coating, and meanwhile, the electrolyte is stored, so that the battery pole piece provided by the embodiment of the application has good safety performance and dynamic performance after being wound into an electrode assembly. The following technical scheme is proposed.
Battery pole piece
In a first aspect, an embodiment of the present application provides a battery pole piece. The surface of the battery pole piece is provided with a first coating and a second coating, and the first coating and the second coating have the effect of relieving stress; wherein the first coating layer and the second coating layer are spaced apart from each other, the first coating layer is disposed on a surface of one end portion of the battery pole piece in the length direction, and the second coating layer is disposed on a surface of the other end portion of the battery pole piece in the length direction.
The battery pole piece is a core component of the battery and mainly plays roles in conducting electricity and storing electricity, and generally comprises a positive pole piece and a negative pole piece. The coating refers to a coating layer containing a functional material, and the coating in the embodiment of the application can be a functional coating layer with a stress relieving effect. Stress refers to the internal force that causes interaction between the parts in the battery pole piece when the battery pole piece is deformed due to external factors (such as charge-discharge expansion stress).
The battery pole piece is provided with two end parts, namely one end part and the other end part along the length direction of the battery pole piece; when the battery pole piece is used for winding the bare cell, the bare cell can be formed by winding from one end part of the battery pole piece in the length direction and ending with the other end part of the battery pole piece.
According to the battery pole piece provided by the embodiment of the application, the first coating and the second coating which are mutually separated are respectively arranged on the surfaces of the two end parts of the battery pole piece along the length direction, after the battery pole piece is wound into the electrode assembly, the coating is additionally arranged on the innermost ring part and the outermost ring part of the electrode assembly, and the stress relieving space can be provided for the generated expansion stress based on the thickening effect of the first coating and the second coating, so that the innermost ring and the outermost ring of the electrode assembly are not easy to cause purple spots and are not easy to separate out lithium, the coating can increase the interlayer spacing of the inner ring and the outer ring of the electrode assembly, and the electrode assembly, in particular the electrolyte retention of the inner ring of the electrode assembly, is facilitated to be improved. Therefore, after the battery pole piece provided by the embodiment of the application is wound into the electrode assembly, the cycle life of the electrode assembly can be prolonged.
In one embodiment, the first coating comprises a first substrate, a first flexible material, a first binder, and a lithium salt. The substrate, the flexible material and the adhesive are used in the first coating, so that the stress generated by cyclic expansion of the first coating on the surface of the battery pole piece can be well relieved, and lithium salt is added in the first coating, so that the first coating part is wound to form the innermost ring of the electrode assembly, and then a lithium ion source can be provided for the inner ring of the electrode assembly, and the dynamic performance of the battery core can be further improved.
Specifically, the first substrate is used as a core functional main body material of the first coating, so that good stress relieving capability can be provided for the first coating. The first flexible material, the first binder, and the lithium salt in the first coating layer may be mixed with the first substrate to form a mixture, or the first flexible material, the first binder, and the lithium salt may be dispersed in doped form within the first substrate film layer to form the first coating layer.
In one embodiment, the second coating comprises a second substrate, a second flexible material, and a second binder. The substrate, flexible material and adhesive are used in the second coating layer to enable the second coating layer to well relieve stress generated by cyclic expansion on the surface of the battery pole piece.
Specifically, the second substrate is used as a core functional main body material of the second coating, so that the second coating can be provided with good stress relieving capability. The second flexible material, the second binder, and the second substrate in the second coating may be mixed to form a mixture, or the second flexible material, the second binder may be dispersed in a doped form within the second substrate film layer to form the second coating.
In one embodiment, the first coating comprises, based on 100% total weight of the first coating: 80-90% of a first base material, 1-5% of a first flexible material, 1-5% of a first binder and 1-5% of lithium salt. By way of example, the first substrate may be 80%, 82%, 84%, 86%, 88%, 90%, etc. typical but non-limiting percentages, the first flexible material may be 1%, 2%, 4%, 5%, etc. typical but non-limiting percentages, the first binder may be 1%, 2%, 4%, 5%, etc. typical but non-limiting percentages, and the lithium salt may be 1%, 2%, 4%, 5%, etc. typical but non-limiting percentages. The first coating formed by the first base material, the first flexible material, the first binder and the lithium salt in the proportion can not only relieve the main normal stress generated by the inner ring due to the expansion of the electrode assembly, but also provide a sufficient lithium ion source for the inner ring of the electrode assembly.
In one embodiment, the second coating comprises, based on 100% total weight of the second coating: 80-90% of a second base material, 1-5% of a second flexible material and 1-5% of a second binder. By way of example, the second substrate may be an exemplary but non-limiting percentage of 80%, 82%, 84%, 86%, 88%, 90%, etc., the second flexible material may be an exemplary but non-limiting percentage of 1%, 2%, 4%, 5%, etc., and the second binder may be an exemplary but non-limiting percentage of 1%, 2%, 4%, 5%, etc. The second coating formed by the second base material, the second flexible material and the second binder according to the proportion can relieve the shearing stress of the outer ring, which is mainly generated by the expansion of the electrode assembly, along the tangential direction.
In an embodiment, the first substrate comprises at least one of a first solid electrolyte material, a first adhesive material, and a first ceramic material; the second substrate includes at least one of a second solid electrolyte material, a second adhesive material, and a second ceramic material. The solid electrolyte material, the adhesive material and the ceramic material have certain toughness and elasticity, and can provide stress relief effect for the coating.
In one embodiment, the first substrate is a first solid electrolyte material or a first ceramic material; because the inner ring of the electrode assembly mainly generates normal stress along the normal direction, the solid electrolyte material and the ceramic material have relatively better toughness, and therefore, after the battery pole piece is wound into the electrode assembly from one end part of the first coating, the first solid electrolyte material or the first ceramic material in the first coating of the inner ring can be used as a base material to better relieve the normal stress.
In one embodiment, the second substrate is a mass ratio (2 to 2.5): (5-6): (2-2.5) a second solid electrolyte material, a second adhesive material and a second ceramic material. The adhesive material has relatively better elasticity because the outer ring of the electrode assembly mainly generates shearing stress along the tangential direction; therefore, after the battery pole piece is wound into the electrode assembly from one end part of the first coating, the second solid electrolyte material and the second ceramic material in the second coating of the outer ring have smaller content and the second adhesive material has larger content, so that the shearing stress can be relieved better.
In one embodiment, the sum of the masses of the first solid electrolyte material and the first ceramic material in the first substrate is greater than the mass of the first tacky material and the sum of the masses of the second solid electrolyte material and the second ceramic material in the second substrate is less than the mass of the second tacky material. Specifically, the first substrate includes a first solid electrolyte material, a first adhesive material, and a first ceramic material, and the sum of the mass of the first solid electrolyte material and the mass of the first ceramic material is 80% or more of the total mass of the first substrate, and the sum of the mass percentages of the first solid electrolyte material and the first ceramic material may be, for example, 80%, 85%, 90%, 100%, etc. typical but non-limiting percentages based on the total mass of the first substrate being 100%. The first substrate of the first coating may better relieve the positive stress at the above-described solid electrolyte material and ceramic material mass ratio conditions.
In an embodiment, the second substrate includes a second solid electrolyte material, a second adhesive material, and a second ceramic material, and the second adhesive material accounts for 60% or more of the total mass of the second substrate. The second tacky material is typically, but not limited to, 60%, 65%, 70%, 72%, 78%, 80%, 85%, 90%, 100%, etc. by mass percent based on 100% of the total mass of the second substrate. The second substrate of the second coating can better relieve the shear stress under the above adhesive material mass ratio conditions.
In an embodiment, the first solid electrolyte material and the second solid electrolyte material may be the same or different, and may specifically include at least one of an organic polymer electrolyte, an oxide electrolyte, and a sulfide electrolyte, respectively; the solid electrolyte material of the type can be used as a core functional substrate of a coating, and can provide good stress relieving capability for the coating.
Wherein, in the solid electrolyte material: organic polymer electrolytes include polyethylene oxide (PEO) and polymers with some structural similarity (polyoxypropylene, polyvinylidene chloride, polyvinylidene fluoride); the oxide electrolyte mainly includes a perovskite-structured lithium steel titanium oxide (LLTO), a garnet-structured lithium steel zirconium oxide (LLZO), a fast ion conductor (LISICON, NASICON), and the like; the sulfide electrolyte mainly comprises a multi-element composite material composed of lithium sulfide and sulfides of elements such as aluminum, phosphorus, silicon, titanium, aluminum, tin and the like. These solid electrolyte materials can provide good stress relief for the coating.
In an embodiment, the first adhesive material and the second adhesive material may be the same or different, and may specifically include at least one of cellulose ester, vinyl polymer, polyester, polyether, polyamide, and cyanoacrylate, respectively and independently; the adhesive material of the type can be used as a core functional substrate of a coating, and can provide good stress relieving capability for the coating.
Wherein the vinyl polymer may comprise one or more of polyvinyl acetate, polyvinyl alcohol, perchloroethylene, polyisobutylene, polyvinyl acetal, ethylene-vinyl acetate copolymer, etc., and the polyester may comprise one or more of polyacrylate, a-cyanoacrylate, etc.
In an embodiment, the first ceramic material and the second ceramic material may be the same or different, and may specifically include at least one of oxide ceramic, nitride ceramic, carbide ceramic, and cermet, respectively. The ceramic material of the type can be used as a core functional substrate of a coating, and can provide good stress relieving capability for the coating.
In an embodiment, the first flexible material and the second flexible material may be the same or different, and specifically may include at least one of a carbon-based material, a transition metal carbon/nitride two-dimensional nano-layered material, and a polymer fiber-based material, respectively. The above flexible material types are used in the coating layer to give the coating layer good plasticity and softness against expansion stress.
The carbon-based material can be one or more of natural graphite, artificial graphite, conductive carbon, graphene, carbon nano tube, carbon fiber and the like. The transition metal carbon/nitride two-dimensional nanolayered material (Mxene-type material) may be a transition metal carbide, nitride or carbonitride. The polymer fiber material can be one or more of Polyimide (PI), non-woven fabrics, organic artificial fibers, inorganic artificial fibers, natural fibers and the like. The material has good flexibility and can be used for relieving expansion stress in a coating.
In an embodiment, the first binder and the second binder may be the same or different, and each independently includes at least one of polyvinylidene fluoride binder, acrylonitrile-based binder, polyurethane-based binder, acrylic binder, styrene-butadiene rubber-based binder, and polyvinylpyrrolidone binder; the use of binders of the above kind in the coating makes it possible to make the coating material firm and less prone to fall off when the coating is subjected to expansion stresses.
In one embodiment, the lithium salt comprises lithium perchlorate (LiClO 4 ) Lithium tetrafluoroborate (LiBF) 4 ) Lithium hexafluoroarsenate (LiAsF) 6 ) Lithium hexafluorophosphate (LiPF) 6 ) At least one of them. The use of lithium salts of the above-mentioned kind in the coating provides a good source of lithium ions.
In one embodiment, the thickness of the first coating is 3-5 μm; the thickness of the second coating is 3-5 mu m; the thickness of the first coating layer may be, for example, 3 μm, 4 μm, 5 μm, etc., which is typical but not limiting, and the thickness of the coating layer may provide a good expansion stress relief space after the battery pole piece is wound into the electrode assembly, and is also advantageous for improving the safety and dynamic performance of the electrode assembly, particularly, the electrolyte retention amount of the inner ring of the electrode assembly.
In one embodiment, the length of the first coating along the length direction of the surface of the pole piece is M1, the total length of the battery pole piece is L, the circumference of a winding needle for winding the battery pole piece is D, and D/2 is more than or equal to M1 and less than or equal to L/4; the length of the second coating along the surface length direction of the pole piece is M2, the total length of the battery pole piece is L, the circumference of a winding needle for winding the battery pole piece is D, and D is less than or equal to M2 and less than or equal to L/4. Further, D/2 is less than or equal to M1 and less than or equal to 2D is less than or equal to L/4, D is less than or equal to M2 and less than or equal to 4D is less than or equal to L/4, and the thickness and the length of the coating are selected, so that a battery pole piece can be wound into an electrode assembly to have a good expansion stress relieving space, and meanwhile, the electrolyte retention quantity of the electrode assembly, particularly the inner ring of the electrode assembly, is also facilitated to be improved, therefore, the cycle life of the electrode assembly can be well prolonged in the parameter range, and the safety performance of a battery can be remarkably improved when the battery is used in the battery.
Specifically, the battery pole piece is wound by adopting an oval winding needle, the circumference of the winding needle can be 80 mm-120 mm, the total length of the battery pole piece can be 3500 mm-4500 mm, and the practical application is the standard. For example, in one embodiment, the circumference of the winding needle may be 100mm, the total length of the battery pole piece may be 4000mm, so that the length of the first coating may be 50mm to 1000mm, further may be 50mm to 200mm, and the length of the second coating may be 100mm to 1000mm, further may be 100mm to 400mm.
In one embodiment, the battery pole piece is a positive pole piece or a negative pole piece. The first coating and the second coating are arranged on the surface of the positive electrode plate or the negative electrode plate, so that the effect of providing an expansion stress relief space and improving the preservation amount of electrolyte can be achieved.
In an embodiment, the first and second coatings may be disposed on one surface of the battery pole piece, and as shown in fig. 1, the surface of the battery pole piece 10 is provided with the first and second coatings 21 and 22, the first and second coatings 21 and 22 being disposed at both ends of the battery pole piece 10 in the length direction of the battery pole piece 10, respectively, and the first and second coatings 21 and 22 being spaced apart from each other. After the battery pole piece 10 is wound into the electrode assembly, the first coating 21 and the second coating 22 (or the second coating 22 and the first coating 21) are additionally added to the innermost ring part and the outermost ring part of the battery pole piece 10 respectively, so that a relief space can be provided for expansion stress generated by charge and discharge cycles of the electrode assembly.
In an embodiment, the first and second coatings may be disposed on both surfaces of the battery pole piece, and as shown in fig. 2, both surfaces of the battery pole piece 10 are provided with the first and second coatings 21 and 22, respectively, the first and second coatings 21 and 22 are disposed at both ends of both surfaces of the battery pole piece 10 in the length direction of the battery pole piece 10, and the first and second coatings 21 and 22 are spaced apart from each other. After the battery pole piece 10 is wound into the electrode assembly, the first coating 21 and the second coating 22 (or the second coating 22 and the first coating 21) are additionally arranged on the opposite surfaces of the innermost ring part and the outermost ring part of the battery pole piece 10, so that a relief space can be better provided for expansion stress generated by charge and discharge cycles of the electrode assembly.
In one embodiment, a battery pole piece includes a current collector and an electrode active layer coupled to the current collector. The first coating layer and the second coating layer may each be provided on the surface of the electrode active layer, or the first coating layer or the second coating layer may be provided on the surface of the current collector without the electrode active layer. As shown in fig. 2, the battery pole piece 10 includes a current collector 101 and an electrode active layer 102 combined with the current collector 101, wherein the two opposite surfaces of the battery pole piece 10 are respectively provided with a first coating 21 and a second coating 22 which are mutually separated, and the first coating 21 and the second coating 22 are arranged on the surface of the electrode active layer 102 facing away from the current collector 101.
Alternatively, as shown in fig. 3, the battery tab 10 includes a current collector 101 and an electrode active layer 102 coupled to the current collector 101, and the surface of the battery tab 10 is provided with a first coating layer 21 and a second coating layer 22 spaced apart from each other. The current collector 101 extends along the length direction of the battery pole piece 10, and a first coating 21 or a second coating 22 is arranged on the surface of the extended exposed current collector 101. That is, the first coating layer 21 on one surface is provided on the current collector 101 (in case of the negative electrode sheet, the positive electrode active layer of the positive electrode sheet is not matched when the surface of the first coating layer 21 is wound up), and the second coating layer 22 on the other end is provided on the electrode active layer 102; the first coating 21 on the other surface is disposed on the electrode active layer 102, and the second coating 22 on the other end is disposed on the current collector 101 (in the case of a negative electrode sheet, the second coating 22 is not disposed on the positive electrode active layer of the positive electrode sheet when the surface is wound). This saves the cost of the electrode active layer 102.
In one embodiment, the battery electrode 10 is a positive electrode or a negative electrode, wherein the current collector 101 is also called positive electrode current collector or negative electrode current collector, and a metal foil or a composite current collector may be used. For example, as the metal foil, aluminum foil may be used. The composite current collector may include a polymeric material base layer and a metal layer formed on at least one surface of the polymeric material base layer. The composite current collector may be formed by forming a metal material (aluminum, aluminum alloy, nickel alloy, titanium alloy, silver alloy, etc.) on a polymer material substrate such as a substrate of polypropylene (PP), polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polystyrene (PS), polyethylene (PE), etc.
In one embodiment, the battery electrode sheet 10 is a positive electrode sheet and the electrode active layer 102 is a positive electrode active layer containing a positive electrode active material. Alternatively, the battery electrode sheet 10 is a negative electrode sheet, and the electrode active layer 102 is a negative electrode active layer containing a negative electrode active material. Wherein the positive electrode active material or the negative electrode active material is a conventional choice in the art, and is not described in detail herein.
Preparation method of battery pole piece
In a second aspect, an embodiment of the present application provides a method for preparing a battery pole piece, as shown in fig. 4, where the method for preparing a battery pole piece includes the following steps:
s01: preparing a first slurry and a second slurry;
s02: the first sizing agent and the second sizing agent are respectively coated on the surfaces of one end part and the other end part of the battery pole piece, dried, and then dried to form a first coating layer and a second coating layer.
According to the embodiment of the application, the prepared first slurry and second slurry are directly coated on the surfaces of two ends of the battery pole piece to form the first coating and the second coating, so that the preparation method is simple in process and easy for industrial production, and after the prepared battery pole piece is wound into the electrode assembly, the expansion stress can be well relieved, so that the electrode assembly is not easy to generate purple spots, lithium is not easy to separate out, and the electrolyte retention amount of the electrode assembly can be improved.
S01: preparing a first slurry and a second slurry; specifically, the raw materials of the first coating and the second coating are prepared into slurry. The first slurry contains a first base material, a first flexible material, a first binder and lithium salt, and the second slurry contains a second base material, a second flexible material and a second binder. The above material selection and ratio are specifically referred to above, and the detailed description is not repeated here.
S02: the slurry coating process can adopt a conventional coating process to respectively coat the first slurry and the second slurry on the two ends of the surface of the battery pole piece along the length direction, specifically, the first coating can be prepared firstly, then the second coating can be prepared, or the second coating can be prepared firstly and then the first coating can be prepared; the length and thickness of the applied coating are as described above and will not be repeated here.
Electrode assembly
In a third aspect, an embodiment of the present application provides an electrode assembly, including an anode, a cathode, and a separator disposed between the anode and the cathode, where the anode, the separator, and the cathode are in a winding structure, and the anode and/or the cathode is a battery pole piece provided in the first aspect of the present application and/or a battery pole piece prepared by a preparation method provided in the second aspect of the present application.
The electrode assembly provided by the embodiment of the application is of a winding structure, wherein the positive electrode and/or the negative electrode is wound by the battery pole piece special for the embodiment of the application, so that the expansion stress of the electrode assembly can be well relieved, the electrode assembly is not easy to generate purple spots and lithium precipitation, and the electrolyte retention amount of the electrode assembly can be improved, and the electrode assembly provided by the embodiment of the application has good cycle life.
In one embodiment, the first coating layer on the surface of the battery pole piece is located on the inner ring of the winding structure, and the second coating layer is located on the outer ring of the winding structure. The first coating formed by material formula selection matching is positioned on the inner ring of the winding structure, so that the normal stress generated by the inner ring mainly along the normal direction can be well relieved, and the second coating formed by material formula selection matching is positioned on the outer ring of the winding structure, so that the shear stress generated by the outer ring mainly along the tangential direction can be well relieved, and the types, the thicknesses and the lengths of the materials of the first coating and the second coating are the same as those described above, and are not repeated here.
In one embodiment, the wound bare cell of the electrode assembly may have various shapes. The plastic film can be applied to bagged aluminum plastic films, aluminum shell packaging, stainless steel rigid packaging and the like, and can be applied to different exterior structures.
For example, taking the battery pole piece 10 provided with the first coating layer 21 and the second coating layer 22 as the negative pole piece according to the embodiment of the present application as an example, a schematic structure of a bare cell wound into a square shell is shown in fig. 5. Wherein, the isolating film 333, the negative electrode pole piece 331 and the positive electrode pole piece 332 are wound into a bare cell of the electrode assembly. While the first coating 21 of the negative electrode tab 331 is located on the negative electrode tab inner ring 3311 and the second coating 22 of the negative electrode tab 331 is located on the negative electrode tab outer ring 3312. Through the effect of the first coating 21 and the second coating 22 on the cathode pole piece inner ring 3311 and the cathode pole piece outer ring 3312 respectively, the expansion stress generated by the charge and discharge of the electrode assembly can be well relieved, so that the electrode assembly is not easy to generate purple spots and lithium precipitation, the electrolyte retention amount of the electrode assembly can be improved, and the electrode assembly has good cycle life.
Battery cell
In a fourth aspect, embodiments of the present application provide a battery comprising the electrode assembly provided in the third aspect of the present application.
By using the electrode assembly provided by the third aspect of the application in a battery, the electrode assembly has a very good cycle life due to the arrangement of the coating, so that the battery has the characteristics of good safety and stable cycle performance in the charge and discharge processes.
In some embodiments, the battery of the embodiments of the present application is a secondary battery, which may include any one of a battery cell, a battery module, and a battery pack.
The battery cell is a battery cell including a battery case and an electrode assembly encapsulated in the battery case. The shape of the battery cell is not particularly limited, and may be cylindrical, square, or any other shape. As shown in fig. 6, a square-structured battery cell 30.
In some embodiments, as shown in fig. 7, the exterior package of the battery cell 30 may include a housing 31 and a cap assembly 32. The housing 31 may include a bottom plate and a side plate coupled to the bottom plate, the bottom plate and the side plate enclosing to form a receiving cavity. The housing 31 has an opening communicating with the accommodating chamber, and the cap assembly 32 is for covering the opening to close the accommodating chamber. The positive electrode, separator and negative electrode sheet included in the secondary battery according to the embodiment of the present application may be formed into the electrode assembly 33 through a winding process and/or a lamination process. The electrode assembly 33 is encapsulated in the receiving chamber. The electrolyte is impregnated in the electrode assembly 33. The number of the electrode assemblies 33 included in the battery cell 30 may be one or more, and may be adjusted according to actual needs.
Methods of preparing the battery cells 30 are well known. In some embodiments, the positive electrode, separator, and negative electrode sheets and electrolyte may be assembled to form the battery cell 30. As an example, the positive electrode, the separator, and the negative electrode sheet may be formed into the electrode assembly 33 through a winding process or a lamination process, the electrode assembly 33 is placed in an exterior package, dried, and then an electrolyte is injected, and the battery cell 30 is obtained through vacuum packaging, standing, formation, shaping, and the like.
The battery module is assembled from the battery cells 30, that is, may contain a plurality of the battery cells 30, and the specific number may be adjusted according to the application and capacity of the battery module.
In some embodiments, fig. 8 is a schematic diagram of a battery module 40 as one example. As shown in fig. 8, in the battery module 40, a plurality of battery cells 30 may be sequentially arranged in the longitudinal direction of the battery module 40. Of course, the arrangement may be performed in any other way. The plurality of battery cells 30 may be further secured by fasteners.
Alternatively, the battery module 40 may further include a housing having an accommodating space in which the plurality of battery cells 30 are accommodated.
The battery pack is assembled from the above battery cells 30, that is, may contain a plurality of battery cells 30, wherein a plurality of the battery cells 30 may be assembled into the above battery module 40. The specific number of battery cells 30 or battery modules 40 included in the battery pack may be adjusted according to the application and capacity of the battery pack.
Fig. 9 and 10 are schematic views of a battery pack 50 as one example, as in the embodiment. A battery box and a plurality of battery modules 40 disposed in the battery box may be included in the battery pack 50. The battery case includes an upper case 51 and a lower case 52, the upper case 51 being for covering the lower case 52 and forming a closed space for accommodating the battery module 40. The plurality of battery modules 40 may be arranged in the battery case in any manner.
Power utilization device
In a fifth aspect, an embodiment of the present application provides an electrical device, where the electrical device includes a battery provided in the fourth aspect of the present application.
By adopting the battery provided by the fourth aspect of the embodiment of the application, the power utilization device has good cycle stability and long service life, and can work for a longer time.
The electric device may be, but is not limited to, a mobile device (e.g., a cellular phone, a notebook computer, etc.), an electric vehicle (e.g., a pure electric vehicle, a hybrid electric vehicle, a plug-in hybrid electric vehicle, an electric bicycle, an electric scooter, an electric golf cart, an electric truck, etc.), an electric train, a ship, a satellite, an energy storage system, etc. The power utilization device may select a secondary battery, a battery module, or a battery pack according to its use requirements.
Fig. 11 is a schematic diagram of an electric device as an example. The electric device is a pure electric vehicle, a hybrid electric vehicle, a plug-in hybrid electric vehicle or the like. To meet the high power and high energy density requirements of the power device, a battery pack or battery module may be employed.
As another example, the power consumption device may be a mobile phone, a tablet computer, a notebook computer, or the like. The electric device is required to be light and thin, and a secondary battery can be used as a power source.
Examples
Hereinafter, embodiments of the present application are described. The following examples are illustrative only and are not to be construed as limiting the application. The examples are not to be construed as limiting the specific techniques or conditions described in the literature in this field or as per the specifications of the product. The reagents or apparatus used were conventional products commercially available without the manufacturer's attention.
1. Negative electrode plate and preparation method embodiment thereof
Example A1
Preparing a negative electrode plate:
graphite, conductive carbon black (Super P), carbon Nano Tube (CNT), styrene Butadiene Rubber (SBR) and sodium carboxymethyl cellulose (CMC-Na) are mixed according to the weight ratio of 95:1.2:0.5:2.1:1.2, mixing and adding the mixture into deionized water, stirring uniformly to prepare negative electrode slurry, uniformly coating the prepared negative electrode slurry on a current collector carbon-coated copper foil with the thickness of 6 mu m, and drying and rolling the current collector carbon-coated copper foil to prepare the negative electrode plate.
Preparing a first slurry and a second slurry: will be 88% Li by weight of the final first coating layer 7 La 3 Zr 2 O 12 (LLZO), 5% conductive carbon (SP), 5% polyvinylidene fluoride, 2% lithium hexafluorophosphate (LiPF) 6 ) The above raw materials are dissolved in a solvent to obtain a first slurry. The final weight percent of the second coating was 90% of the substrate [ polyacrylate: li (Li) 7 La 3 Zr 2 O 12 : alumina at 6:2: 2. composition of mass ratio]And 5% of conductive carbon and 5% of polyvinylidene fluoride, and dissolving the raw materials in a solvent to obtain second slurry.
And (3) coating the first slurry on one end (winding starting position, which is positioned on the inner ring of the bare cell) of the negative electrode plate, coating the second slurry on the other end (winding ending position, which is positioned on the outer ring of the bare cell) of the negative electrode plate, and drying to obtain a first coating and a second coating (the thickness of the two coatings is 5um, the length of the first coating is 80mm, and the length of the second coating is 150 mm). Thereby forming the final negative electrode sheet product.
Example A2
Preparation of negative electrode sheet except that no lithium hexafluorophosphate (LiPF) was added to the first slurry formulation 6 ) The other components are the same as in example A1.
Example A3
The negative electrode sheet was prepared in the same manner as in example A1, except that the formulation of the first paste was different.
In this example, the first slurry will be 88% polyethylene oxide (PEO), 5% conductive carbon (SP), 5% polyvinylidene fluoride, 2% lithium hexafluorophosphate (LiPF) in final weight percent of the first coating 6 ) And (5) preparing.
Example A4
The negative electrode sheet was prepared in the same manner as in example A1, except that the formulation of the first paste was different.
In this example, the first slurry would be 88% aluminum oxide, 5% conductive carbon (SP), 5% polyvinylidene fluoride, 2% lithium hexafluorophosphate (LiPF) by final weight of the first coating 6 ) And (5) preparing.
Example A5
The negative electrode sheet was prepared in the same manner as in example A1, except that the formulation of the first paste was different.
In this example, the first paste will be 88% substrate by weight of the final first coating layer [ polyacrylate: li (Li) 7 La 3 Zr 2 O 12 : alumina was used in a 2:4: 4. composition of mass ratio]5% conductive carbon (SP), 5% polyvinylidene fluoride, 2% lithium hexafluorophosphate (LiPF) 6 ) And (5) preparing.
Comparative example A1
The negative electrode sheet was prepared in the same manner as in example A1, except that the first coating layer and the second coating layer were not applied.
Comparative example A2
The negative electrode sheet was prepared in the same manner as in example A1 except that the entire surface of the negative electrode sheet was coated with a layer of aluminum oxide.
2. Secondary Battery cell examples
Examples B1 to B5 and comparative examples B1 to B2;
the present examples B1 to B5 and comparative examples B1 to B2 provide secondary battery cells each including a bare cell formed of a positive electrode tab, a separator, and a negative electrode tab, and further including an electrolyte. Among them, the negative electrode sheets of examples B1 to B5 and comparative examples B1 to B2 correspond to the negative electrode sheets provided in examples A1 to A5 and comparative examples A1 to A2, respectively. The negative electrode tab in the above embodiment A1 is used as the negative electrode tab in the battery cell of the secondary battery embodiment B1, the negative electrode tab in the embodiment A2 is used as the negative electrode tab in the battery cell of the secondary battery embodiment B2, and so on, and the negative electrode tab in the comparative example A2 is used as the negative electrode tab in the battery cell of the battery comparative example B2.
The preparation method of the secondary battery monomer comprises the following steps:
preparing a positive electrode plate: lithium iron phosphate (LiFePO) as a cathode active material 4 ) Vinylidene fluoride (PVDF), conductive carbon black (SP), carbon Nanotubes (CNT), polyvinylpyrrolidone, 94 by weight: 2:2:1:1 is dissolved in N-methyl pyrrolidone (NMP) and evenly coated on an aluminum foil with 13um, and then the positive plate is prepared through drying, rolling and slitting.
Negative electrode sheets the negative electrode sheets provided with reference to examples A1 to A5 and comparative examples A1 to A2.
Electrolyte solution: lithium hexafluorophosphate with the concentration of 1M, and the organic solvent is ethylene carbonate, dimethyl carbonate and methyl ethyl carbonate according to the mass ratio of 1:1:1 proportion of mixed solvent.
And (3) secondary battery assembly: and sequentially superposing the prepared negative pole piece, positive pole piece and polypropylene porous isolating film, preparing a battery winding core through a winding process, and preparing the cylindrical lithium ion secondary battery through the procedures of packaging, liquid injection, formation, separation and the like, namely the secondary battery monomer.
Performance testing
The secondary battery cells of the above examples and comparative examples were respectively tested.
(1) And (3) interface observation:
interface after 500 cycles at 25 ℃, 3C: after the temperature is 25 ℃ and the 3C is charged to the cut-off voltage, the holding voltage is continuously charged to 0.05C, the 3C is discharged to the cut-off voltage, 1 cycle is completed, and after the 500 times are repeated, the interface is fully charged and disassembled.
(2) And (3) testing the cycle performance:
the cell was left to stand at room temperature for 2h. Constant-current charging is carried out on the battery to 4.25V under the current of 1/3C, constant-voltage charging is continued until the charging current is smaller than 0.05C, and then the battery is cut off; suspending for 5min; constant current discharge of 1C current to 2.8V; pause for 5min. The above is one charge-discharge cycle of the battery, and the capacity retention rate is calculated after 500 cycles of the battery.
The test results are shown in Table 1.
From the test results in table 1, it can be seen that: compared with the comparative example, the secondary battery of the embodiment of the application has no purple stain, no lithium precipitation and better cycle capacity retention rate.
Finally, it should be noted that: the above embodiments are only for illustrating the technical solution of the present application, and not for limiting the same; although the application has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical scheme described in the foregoing embodiments can be modified or some or all of the technical features thereof can be replaced by equivalents; such modifications and substitutions do not depart from the spirit of the application, and are intended to be included within the scope of the appended claims and description. 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 (15)
1. The battery pole piece is characterized in that a first coating layer and a second coating layer capable of relieving stress are arranged on the surface of one end part of the battery pole piece in the length direction, the second coating layer is arranged on the surface of the other end part of the battery pole piece in the length direction, the first coating layer and the second coating layer are mutually separated, the first coating layer comprises a first base material, a first flexible material, a first binder and lithium salt, and the second coating layer comprises a second base material, a second flexible material and a second binder; the battery pole piece is in a winding structure along the length direction.
2. The battery pole piece of claim 1, wherein the first coating comprises, based on 100% total weight of the first coating: 80-90% of the first base material, 1-5% of the first flexible material, 1-5% of the first binder and 1-5% of the lithium salt; and/or the number of the groups of groups,
the second coating layer comprises, based on 100% of the total weight of the second coating layer: 80-90% of a second base material, 1-5% of a second flexible material and 1-5% of a second binder.
3. The battery pole piece of claim 1, wherein the first substrate comprises at least one of a first solid electrolyte material, a first adhesive material, and a first ceramic material; and/or the number of the groups of groups,
the second substrate includes at least one of a second solid electrolyte material, a second adhesive material, and a second ceramic material.
4. The battery pole piece of claim 3, wherein the first substrate is the first solid electrolyte material or the first ceramic material; and/or the number of the groups of groups,
the second base material is prepared from the following components in percentage by mass (2-2.5): (5-6): (2-2.5) the second solid electrolyte material, the second adhesive material, and the second ceramic material.
5. The battery pole piece of claim 3, wherein the first substrate comprises the first solid electrolyte material, the first adhesive material, and the first ceramic material, and wherein the sum of the mass of the first solid electrolyte material and the mass of the first ceramic material is 80% or more of the total mass of the first substrate; and/or the number of the groups of groups,
the second substrate comprises the second solid electrolyte material, the second adhesive material and the second ceramic material, and the percentage of the second adhesive material in the total mass of the second substrate is more than or equal to 60%.
6. A battery pole piece according to any of claims 3-5, characterized in that one or more of the following (1) - (3) are fulfilled:
(1) The first solid electrolyte material and the second solid electrolyte material independently include at least one of an organic polymer-based electrolyte, an oxide-based electrolyte, and a sulfide-based electrolyte;
(2) The first adhesive material and the second adhesive material independently comprise at least one of cellulose ester, vinyl polymer, polyester, polyether, polyamide, and cyanoacrylate;
(3) The first ceramic material and the second ceramic material independently comprise at least one of an oxide ceramic, a nitride ceramic, a carbide ceramic, and a cermet.
7. A battery pole piece according to any of claims 1-5, characterized in that one or more of the following (1) - (3) are fulfilled:
(1) The first flexible material and the second flexible material independently comprise at least one of a carbon-based material, a transition metal carbon/nitride two-dimensional nano layered material and a polymer fiber material;
(2) The first binder and the second binder independently comprise at least one of polyvinylidene fluoride binder, acrylonitrile binder, polyurethane binder, acrylic binder, styrene-butadiene rubber binder and polyvinylpyrrolidone binder;
(3) The lithium salt includes at least one of lithium perchlorate, lithium tetrafluoroborate, lithium hexafluoroarsenate, and lithium hexafluorophosphate.
8. The battery pole piece of any of claims 1-5, wherein one or more of the following (1) - (4) are satisfied:
(1) The thickness of the first coating is 3-5 mu m;
(2) The thickness of the second coating is 3-5 mu m;
(3) The length of the first coating along the surface length direction of the battery pole piece is M1, the total length of the battery pole piece is L, the circumference of a winding needle for winding the battery pole piece is D, and D/2 is more than or equal to M1 and less than or equal to L/4;
(4) The length of the second coating along the surface length direction of the battery pole piece is M2, the total length of the battery pole piece is L, the circumference of a winding needle for winding the battery pole piece is D, and D is more than or equal to M2 and less than or equal to L/4.
9. The battery pole piece of any of claims 1-5, wherein the battery pole piece comprises a current collector and an electrode active layer associated with the current collector, the first coating and the second coating being disposed on a surface of the electrode active layer facing away from the current collector; or, the current collector extends along the length direction of the battery pole piece, and the first coating or the second coating is arranged on the surface of the extended exposed current collector.
10. The battery pole piece of any of claims 1-5, wherein the battery pole piece is a positive pole piece or a negative pole piece.
11. A method of manufacturing a battery pole piece according to any one of claims 1 to 9, comprising the steps of:
preparing a first slurry and a second slurry;
and coating the first slurry and the second slurry on the surfaces of one end part and the other end part of the battery pole piece respectively, and drying to form the first coating and the second coating.
12. An electrode assembly comprising a positive electrode, a negative electrode and a separator disposed between the positive electrode and the negative electrode, wherein the positive electrode, the separator and the negative electrode are in a wound structure, and the positive electrode and/or the negative electrode is the battery pole piece according to any one of claims 1 to 9 and/or the battery pole piece prepared by the preparation method according to claim 11.
13. The electrode assembly of claim 12, wherein the first coating of the battery pole piece surface is located on an inner ring of the wound structure and the second coating is located on an outer ring of the wound structure.
14. A battery comprising the electrode assembly of claim 12 or 13.
15. An electrical device comprising the battery of claim 14.
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| CN117133927B (en) * | 2023-10-25 | 2024-04-02 | 宁德时代新能源科技股份有限公司 | Composite positive current collector, positive pole piece, winding structure battery core and power utilization device |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2011100674A (en) * | 2009-11-09 | 2011-05-19 | Panasonic Corp | Electrode group for nonaqueous secondary battery, and nonaqueous secondary battery using this |
| CN104332658A (en) * | 2014-10-24 | 2015-02-04 | 东莞锂威能源科技有限公司 | Lithium ion battery with high safety performance |
| CN110429328A (en) * | 2019-08-09 | 2019-11-08 | 珠海冠宇电池有限公司 | A method of improving inside battery temperature rise |
| CN112750973A (en) * | 2020-12-31 | 2021-05-04 | 蜂巢能源科技有限公司 | Pole piece unit and preparation method thereof |
| CN114464895A (en) * | 2022-01-12 | 2022-05-10 | 力神（青岛）新能源有限公司 | Preparation method and application of square laminated lithium ion battery capable of improving stress |
-
2023
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Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2011100674A (en) * | 2009-11-09 | 2011-05-19 | Panasonic Corp | Electrode group for nonaqueous secondary battery, and nonaqueous secondary battery using this |
| CN104332658A (en) * | 2014-10-24 | 2015-02-04 | 东莞锂威能源科技有限公司 | Lithium ion battery with high safety performance |
| CN110429328A (en) * | 2019-08-09 | 2019-11-08 | 珠海冠宇电池有限公司 | A method of improving inside battery temperature rise |
| CN112750973A (en) * | 2020-12-31 | 2021-05-04 | 蜂巢能源科技有限公司 | Pole piece unit and preparation method thereof |
| CN114464895A (en) * | 2022-01-12 | 2022-05-10 | 力神（青岛）新能源有限公司 | Preparation method and application of square laminated lithium ion battery capable of improving stress |
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