CN116111042A - Positive electrode sheet, secondary battery, and electronic device - Google Patents
Positive electrode sheet, secondary battery, and electronic device Download PDFInfo
- Publication number
- CN116111042A CN116111042A CN202310381155.3A CN202310381155A CN116111042A CN 116111042 A CN116111042 A CN 116111042A CN 202310381155 A CN202310381155 A CN 202310381155A CN 116111042 A CN116111042 A CN 116111042A
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- Prior art keywords
- positive electrode
- electrode active
- active material
- film layer
- material film
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Images
Classifications
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- 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
- H01M4/131—Electrodes based on mixed oxides or hydroxides, or on mixtures of oxides or hydroxides, e.g. LiCoOx
-
- 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
- H01M10/0525—Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
-
- 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
- H01M4/36—Selection of substances as active materials, active masses, active liquids
- H01M4/48—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides
- H01M4/52—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides of nickel, cobalt or iron
- H01M4/525—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides of nickel, cobalt or iron of mixed oxides or hydroxides containing iron, cobalt or nickel for inserting or intercalating light metals, e.g. LiNiO2, LiCoO2 or LiCoOxFy
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- 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
- H01M4/62—Selection of inactive substances as ingredients for active masses, e.g. binders, fillers
- H01M4/628—Inhibitors, e.g. gassing inhibitors, corrosion inhibitors
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- 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
- H01M2004/021—Physical characteristics, e.g. porosity, surface area
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- 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
- H01M2004/026—Electrodes composed of, or comprising, active material characterised by the polarity
- H01M2004/028—Positive electrodes
-
- 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
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- Battery Electrode And Active Subsutance (AREA)
Abstract
The application discloses positive pole piece, secondary cell and electron device, positive pole piece includes: the positive electrode active material film layer is arranged between the positive electrode current collector and the first positive electrode active material film layer, wherein the first positive electrode active material film layer comprises a pore-forming agent, and the pore-forming agent comprises at least one of lithium salt or solid-phase organic compound; the lithium salt comprises one or more of difluoro-sulfonimide lithium salt, difluoro-oxalato-borate lithium, difluoro-oxalato-phosphate lithium and difluoro-phosphate lithium; the solid organic compound comprises one or more of vinyl sulfate, vinyl sulfite, phosphite and adiponitrile. The pore-forming agent dissolves or oxidizes and dissolves in the liquid injection and positive electrode charging and discharging processes, so that the ion impedance of the positive electrode plate is reduced, and the dynamic performance of the positive electrode plate is improved.
Description
Technical Field
The application belongs to the technical field of batteries, and particularly relates to a positive electrode plate, a secondary battery and an electronic device.
Background
In recent years, new energy batteries represented by lithium ion batteries have been widely used, and have been attracting more attention due to their excellent properties such as high energy density, high operating voltage, long cycle life, small size, light weight, and environmental friendliness.
Currently, batteries typified by lithium ion secondary batteries have been widely used in the fields of electric automobiles, mobile electronic devices, and the like. With the continuous development of electric automobiles and mobile electronic devices, the requirements of people on the comprehensive performance of batteries are increasing. Therefore, providing a battery with overall improved comprehensive performance is a technical problem to be solved at present.
Disclosure of Invention
An object of the present application is to provide a positive electrode sheet, a secondary battery, and an electronic device capable of improving the dynamic performance of a secondary battery including the same, and further to provide a secondary battery and an electronic device having improved dynamic performance.
A first aspect of embodiments of the present application provides a positive electrode sheet, including:
a positive electrode current collector; and
a first positive electrode active material film layer and a second positive electrode active material film layer, wherein the first positive electrode active material film layer is arranged on one side of the positive electrode current collector, the second positive electrode active material film layer is arranged between the positive electrode current collector and the first positive electrode active material film layer,
Wherein the first positive electrode active material film layer comprises a pore-forming agent, and the pore-forming agent comprises at least one of lithium salt or solid-phase organic compound; the lithium salt comprises one or more of difluoro-sulfonimide lithium salt, difluoro-oxalato-borate lithium, difluoro-oxalato-phosphate lithium and difluoro-phosphate lithium; the solid organic compound comprises one or more of vinyl sulfate, vinyl sulfite, phosphite and adiponitrile.
According to the technical scheme of the embodiment of the application, the positive electrode plate comprises: and the first positive electrode active material film layer containing the pore-forming agent is added, so that the wetting rate of the electrolyte is improved, the wettability and the liquid retention amount are increased, the ion impedance of the positive electrode plate is reduced, and the dynamic performance including the charge and discharge performance is improved in the process of injecting the liquid into the positive electrode plate and charging and discharging the positive electrode.
In addition, the pore-forming agent is contained in the first positive electrode active material film layer, so that the first positive electrode active material film layer firstly obtains a dispersed porous structure; compared with the second positive electrode active material film layer, the first positive electrode active material film layer is close to the surface of the positive electrode plate, and the first positive electrode active material film layer is larger in porosity compared with the second positive electrode active material film layer, so that the positive electrode plate has gradient distribution porosity, the wetting rate of electrolyte on the outer layer of the positive electrode plate, particularly the wetting rate in the initial stage of liquid injection and positive electrode charge and discharge, is further improved, and therefore the dynamic performance including charge and discharge performance is improved.
According to an embodiment of one aspect of the present application, the first positive electrode active material film layer comprises 0.01% -5% of pore-forming agent based on the total weight of the first positive electrode active material film layer.
According to an embodiment of one aspect of the present application, the first positive electrode active material film layer comprises 0.5% -2% of pore-forming agent based on the total weight of the first positive electrode active material film layer.
According to an embodiment of one aspect of the present application, the second positive electrode active material film layer includes a pore-forming agent, wherein the mass percentage of the pore-forming agent in the second positive electrode active material film layer is smaller than the mass percentage of the pore-forming agent in the first positive electrode active material film layer.
According to an embodiment of one aspect of the present application, the average particle diameter Dv50 of the pore-forming agent is 1 to 10 μm.
According to an embodiment of one aspect of the present application, the pore former is in particulate form.
According to an embodiment of one aspect of the present application, the thickness ratio of the first positive electrode active material film layer and the second positive electrode active material film layer is 1: (1-5).
According to an embodiment of one aspect of the present application, the thickness of the second positive electrode active material film layer is 15 to 50 μm.
According to an embodiment of one aspect of the present application, the thickness of the first positive electrode active material film layer is 5 to 25 μm.
According to an embodiment of one aspect of the present application, the first positive electrode active material film layer includes first positive electrode active particles; the second positive electrode active material film layer includes second positive electrode active particles; the ratio of the average particle diameter Dv50 of the first positive electrode active particles to the average particle diameter Dv50 of the second positive electrode active particles was 1: (0.8-1.2).
According to an embodiment of one aspect of the present application, the average particle diameter Dv50 of the first positive electrode active particles is 2 to 15 μm.
According to an embodiment of one aspect of the present application, the average particle diameter Dv50 of the second positive electrode active particles is 2 to 15 μm.
A second aspect of the embodiments of the present application provides a secondary battery, including: the positive electrode sheet, the negative electrode sheet, the electrolyte and the separator which are spaced between the positive electrode sheet and the negative electrode sheet of the first aspect.
According to an embodiment of an aspect of the present application, the electrolyte comprises a carbonate comprising one or more of ethylene carbonate, propylene carbonate, diethyl carbonate, dimethyl carbonate.
According to an embodiment of one aspect of the application, the mass content of the carbonate in the electrolyte is in the range of 20% -90%.
According to an embodiment of one aspect of the present application, the ratio of the initial content of the pore-forming agent in the first positive electrode active material film layer to the content of the pore-forming agent in the first positive electrode active material film layer after 20 charge and discharge of the secondary battery is 1 (0.01-0.2).
A third aspect of embodiments of the present application provides an electronic device including the secondary battery of the second aspect.
The positive electrode plate provided by the embodiment of the application comprises the pore-forming agent and the first positive electrode active material film layer, so that the positive electrode plate can obtain a dispersed pore structure, the transmission impedance of active ions such as lithium ions and sodium ions is reduced, the kinetic performance of a secondary battery comprising the positive electrode plate is improved, and the electronic device comprises the secondary battery provided by the application, so that the electronic device has at least the same advantages as the secondary battery.
Drawings
In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following description will briefly explain the drawings that are required to be used in the embodiments of the present application. It is apparent that the drawings described below are only some embodiments of the present application, and that other drawings may be obtained from the drawings without inventive work for those of ordinary skill in the art.
FIG. 1 shows a schematic cross-sectional view of a positive electrode sheet structure as an example;
FIG. 2 shows a schematic view of a positive electrode sheet structure containing a pore-forming agent as one example;
FIG. 3 shows a topography of the surface of a first positive electrode active material film layer of example 2;
FIG. 4 shows a topography of example 2 after dissolution of the surface pore-former of the first positive electrode active material film layer;
FIG. 5 shows a profile view of a cross section of a positive electrode sheet of example 2;
fig. 6 shows a secondary battery of a square structure as an example;
fig. 7 shows an exploded schematic view of a secondary battery as an example;
fig. 8 shows an electronic apparatus as an example.
In the drawings, the drawings are not necessarily to scale.
Detailed Description
Hereinafter, embodiments of an electrode assembly, a method of manufacturing the same, a secondary battery, a battery module, a battery pack, and an electric device of the present application are specifically disclosed with reference to the accompanying drawings as appropriate. However, unnecessary detailed description may be omitted. For example, detailed descriptions of well-known matters and repeated descriptions of the actual same structure may be omitted. This is to avoid that the following description becomes unnecessarily lengthy, facilitating the understanding of those skilled in the art. Furthermore, the drawings and the following description are provided for a full understanding of the present application by those skilled in the art, and are not intended to limit the subject matter recited in the claims.
The "range" disclosed herein is defined in terms of lower and upper limits, with a given range being defined by the selection of a lower and an upper limit, the selected lower and upper limits defining the boundaries of the particular range. Ranges that are defined in this way can be inclusive or exclusive of the endpoints, and any combination can be made, i.e., any lower limit can be combined with any upper limit to form a range. For example, if ranges of 60-120 and 80-110 are listed for a particular parameter, it is understood that ranges of 60-110 and 80-120 are also contemplated. Furthermore, if the minimum range values 1 and 2 are listed, and if the maximum range values 3,4 and 5 are listed, the following ranges are all contemplated: 1-3, 1-4, 1-5, 2-3, 2-4 and 2-5. In this application, unless otherwise indicated, the numerical range "a-b" represents a shorthand representation of any combination of real numbers between a and b, where a and b are both real numbers. For example, the numerical range "0-5" means that all real numbers between "0-5" have been listed throughout, and "0-5" is simply a shorthand representation of a combination of these values. When a certain parameter is expressed as an integer of 2 or more, it is disclosed that the parameter is, for example, an integer of 2, 3,4, 5, 6, 7, 8, 9, 10, 11, 12 or the like.
All embodiments and alternative embodiments of the present application may be combined with each other to form new solutions, and such solutions should be considered to be included in the disclosure of the present application, unless specifically stated otherwise.
All technical features and optional technical features of the present application may be combined with each other to form new technical solutions, if not specifically stated, and such technical solutions should be considered as included in the disclosure of the present application.
All steps of the present application may be performed sequentially or randomly, preferably sequentially, unless otherwise indicated. For example, the method comprises steps (a) and (b), meaning that the method may comprise steps (a) and (b) performed sequentially, or may comprise steps (b) and (a) performed sequentially. For example, the method may further include step (c), which means that step (c) may be added to the method in any order, for example, the method may include steps (a), (b) and (c), may include steps (a), (c) and (b), may include steps (c), (a) and (b), and the like.
Reference herein to "comprising" and "including" means open ended, as well as closed ended, unless otherwise noted. For example, the terms "comprising" and "comprises" may mean that other components not listed may be included or included, or that only listed components may be included or included.
The term "or" is inclusive in this application, unless otherwise specified. For example, the phrase "a or B" means "a, B, or both a and B. More specifically, either of the following conditions satisfies the condition "a or B": a is true (or present) and B is false (or absent); a is false (or absent) and B is true (or present); or both A and B are true (or present).
The terms "coupled," "connected," and "connected," as used herein, are defined in a broad sense as connected, either permanently connected, detachably connected, or integrally connected, unless otherwise specified; can be directly connected or indirectly connected through an intermediate medium, and can be communication between two elements. The specific meaning of the terms in this application will be understood by those of ordinary skill in the art as the case may be.
The term "attached" in this application refers to being attached by adhesion, coating, or the like, unless otherwise specified.
The terms "first," "second," "third," "fourth," and the like in this application, unless otherwise specified, are used for distinguishing between different objects and not necessarily for describing a sequential or chronological order.
In the present application, the term "active ion" refers to an ion capable of being inserted and extracted back and forth between the positive and negative electrodes of the secondary battery, including, but not limited to, lithium ion, sodium ion, and the like, unless otherwise specified.
The term "plurality" as used herein refers to more than two (including two). The term "plurality" as used herein refers to two or more (including two).
In the present application, the secondary battery may include a lithium ion battery, a sodium ion battery, and the like, which is not limited by the embodiment of the present application. The secondary battery may be an aqueous battery or an oil battery, and the embodiment of the present application is not limited thereto. The secondary battery may have a flat body, a rectangular parallelepiped, or other shape, etc., and the embodiment of the present application is not limited thereto.
The battery is the main angle of new energy at present, and the development of the battery has great influence on consumer power supplies, energy storage power supplies and the like, and the battery is gradually popularized and widely used, so that the requirements on the performance of the battery are higher and higher, such as the rapid charge and discharge performance.
The high energy density of the battery can be achieved by thicker paste application and higher compacted density, but the high energy density is accompanied by severe deterioration of charge resistance, and performance degradation of charge speed and charge time.
According to research, the high energy density needs to improve the active material ratio, the higher active material is inevitably required to cause the pole piece dynamics to be poor, the charging speed is reduced, the cell performance is unstable, and the factors become great barriers for improving the battery performance. The method solves the key problem of improving the charge and discharge actions and the dynamic performance of the battery due to the high impedance of the positive electrode plate under the premise of high energy density.
In addition, when the secondary battery is charged and discharged, active ions, such as lithium ions, in the positive electrode active material of the positive electrode active material film layer are extracted and intercalated to thereby realize charge and discharge. In addition, as the number of battery cycles increases, the impedance of the positive electrode tab increases, resulting in reduced battery performance.
Therefore, effective technical means are required to improve the dynamic performance of the battery including charge and discharge performance.
Positive electrode plate
A first aspect of the embodiments of the present application provides a positive electrode sheet, referring to fig. 1, including:
a positive electrode current collector 100; and
the positive electrode active material comprises a first positive electrode active material film layer 200 and a second positive electrode active material film layer 300, wherein the first positive electrode active material film layer 200 is arranged on one side of the positive electrode current collector 100, and the second positive electrode active material film layer 300 is arranged between the positive electrode current collector 100 and the first positive electrode active material film layer 200.
Wherein the first positive electrode active material film layer comprises a pore-forming agent, and the pore-forming agent comprises at least one of lithium salt or solid-phase organic compound; the lithium salt comprises one or more of difluoro-sulfonimide lithium salt, difluoro-oxalato-borate lithium, difluoro-oxalato-phosphate lithium and difluoro-phosphate lithium; the solid organic compound comprises one or more of vinyl sulfate, vinyl sulfite, phosphite and adiponitrile.
In the related technology, aiming at the positive pole piece with larger impedance, the porosity of the pole piece can be directly improved by adopting double-layer coating, the obstruction of ions at an interface is reduced, and the dynamic performance is improved, but the compaction density or the energy density of the positive pole piece are influenced by the method.
It has been found that increasing the porosity of the pole piece to reduce the conduction resistance of active ions including lithium ions, sodium ions in the battery pole piece is an effective solution to improve the battery kinetics. In the positive electrode sheet according to the embodiment of the present application, a pore-forming agent including a lithium salt and/or a solid-phase organic compound is added to the positive electrode active material film layer.
It can be understood that: the pore-forming agent comprises a lithium salt and/or a solid phase organic compound. In the process of filling liquid and subsequent charge-discharge circulation of the battery containing the positive electrode plate, the pore-forming agent is dissolved or oxidized and decomposed, so that more pores can be formed. The formation of pores improves the porosity of the first positive electrode active material film layer, thereby improving the wettability of electrolyte and the conductivity of active ions such as lithium ions, sodium ions and the like, so that the resistance of the battery core ions can be obviously reduced, and the dynamic performance of the secondary battery such as low-temperature performance, charge-discharge performance and the like can be obviously improved.
In addition, the first positive electrode active material film layer contains a pore-forming agent, and the pore-forming agent is dissolved or oxidized and decomposed in the process of liquid injection and subsequent charge-discharge circulation, so that the porosity of the first positive electrode active material film layer is higher than that of the second positive electrode active material film layer, the porosity of the positive electrode plate has gradient change, the porosity of the surface layer of the electrode plate or the bottleneck area of the first positive electrode active material layer can be increased, the conductivity of active ions is improved, and the dynamic performance of the electrode plate in the area can be improved. The porosity of the first positive electrode active material film layer is larger than that of the second positive electrode active material film layer, and electrolyte contained during infiltration can be used for improving the bonding effect with the isolating film during use, so that the cycle performance of the battery is improved.
Embodiments of the present application allow for a positive electrode active material film layer of greater thickness and/or higher compacted density. In general, a positive electrode active material film layer having a larger thickness and/or a higher compacted density causes problems such as lower porosity, increased ion resistance, and the like, thereby resulting in deterioration of the dynamic performance of the battery. However, embodiments of the present application may advantageously solve the above-described problems by adding a specific pore-forming agent to the first positive electrode active material film layer.
According to embodiments of the present application, the pore-forming agent undergoes dissolution or oxidative decomposition during the injection and subsequent charge-discharge cycles (e.g., formation) of the battery. The dissolved pore-forming agent or oxidation products of the pore-forming agent migrate to the electrode surface and participate in the formation of an electrode surface protective film (such as SEI or CEI), thereby enhancing the film forming performance of the electrode surface protective film of the battery. Enhancing the film forming property of the battery electrode surface protective film is very advantageous for improving the overall properties of the battery, particularly the cycle properties.
In some embodiments, where the pore-forming agent comprises a lithium salt, such pore-forming agent may provide a portion of the lithium ions required to form the electrode surface protective film, or may supplement a portion of the lithium ions consumed to form the electrode surface protective film. Accordingly, the embodiments of the present application can advantageously reduce the decrease in battery capacity caused by the consumption of lithium ions by the formation of the electrode surface protective film.
According to the embodiment of the application, the pore-forming agent added in the positive electrode active material film layer does not have an undesirable side reaction with the raw materials used in the process of preparing the positive electrode active material film layer slurry, and thus does not adversely affect or bring an additional burden to the preparation process of the positive electrode sheet.
Referring to fig. 2, a positive electrode tab of an embodiment of the present application is shown, including a positive electrode current collector 100; and a first positive electrode active material film layer 200 and a second positive electrode active material film layer 300. The pore-forming agent 400 is located in the first positive electrode active material film layer 200.
In some embodiments, the first positive electrode active material film layer is located on the positive electrode sheet surface. The arrangement can lead the pore-forming agent in the first positive electrode active material film layer to be dissolved or oxidized and decomposed at first, improve the porosity and reduce the ionic resistance at the initial stage of the liquid injection and the subsequent charge-discharge cycle.
In some embodiments, the first positive electrode active material film layer comprises 0.01% -5% pore-forming agent, based on the total weight of the first positive electrode active material film layer. The content of the pore-forming agent is in the range, which is beneficial to improving the porosity and ion impedance of the positive pole piece; the addition amount of the pore-forming agent is too small, and the pore-forming effect is not obvious; the excessive addition of pore-forming agent, organic group after pore-forming agent dissolves in charge-discharge process can adhere to positive and negative pole piece and diaphragm, thicken SEI membrane/CEI membrane or block the barrier film hole, cause the internal resistance to increase. In some embodiments, the pore-forming agent may be present in the positive electrode active material film layer in an amount of any one of 0.01% -1%, 0.1% -2%, 0.5% -1%, 0.5% -2%, 0.5% -3%, 0.5% -4%, or 0.5% -5%.
The mass content of the pore-forming agent can be obtained by a test method of ultrasonic separation and soaking, heating and dissolving. As an example, a positive electrode plate sample with a certain mass is weighed, an active layer is separated by using N-methyl pyrrolidone (NMP) through ultrasonic rotation, then active slurry is dried and ground into powder with a mass of m0, then the powder is soaked for 24 hours at a high temperature of 150 ℃ by using EC/DMC and other solutions, and then the powder is dried, and the difference between the mass of the powder and the mass of the powder before and after the powder is measured to be the mass m1 of the pore-forming agent; after removing the positive electrode current collector, weighing the mass m0 of a positive electrode active material film sample, soaking the powder which contains the carbon conductive agent and is dried again with the mass content of m1/m0 in concentrated sulfuric acid, and filtering the filtered filter residue to obtain a binder and conductive carbon m2; then the temperature is raised to 800 ℃ by utilizing TG to decompose the binder, and the rest is conductive carbon m3, so that the mass content of each substance is calculated: pore-forming agent m1, conductive agent m3, binder m2-m3, active substance m0-m1-m2.
In some embodiments, the first positive electrode active material film layer comprises 0.5% -2% pore-forming agent, based on the total weight of the first positive electrode active material film layer. In some embodiments, the content of the pore-forming agent in the first positive electrode active material film layer may be 0.5% -1%, 0.5% -2%, 0.6% -1%, 0.6% -2%, 0.7% -1%, 0.7% -2%, 0.8% -1%, 0.8% -2%, 0.9% -1%, 0.9% -1.2%, 0.9% -1.3%, 0.9% -1.4%, 0.9% -1.5%, 0.9% -1.6%, 0.9% -1.7%, 0.9% -1.8%, 0.9% -1.9%, 0.9% -2%, 1.0% -1.1%, 1.0% -1.2%, 1.0% -1.3%, 1.0% -1.4%, 1.0% -1.5%, 1.0% -1.6%, 1.0% -1.7%, 1.0% -1.8%, or 1.0% -1.2%. At the moment, the porosity in use can be effectively improved while the energy density of the positive electrode plate is not influenced, and meanwhile, the structural stability of the first positive electrode active material film layer is ensured.
In some embodiments, the first positive electrode active material film layer comprises 5% -10% by volume of the pore former based on the total volume of the first positive electrode active material film layer. In the process of filling liquid and subsequent charge-discharge cycles of the battery comprising the positive electrode plate, the first positive electrode active material film layer can improve pores accounting for 5% -10% of the total volume of the positive electrode active material film layer. In some embodiments, the pore former may be present in the first positive electrode active material film layer in an amount of 5%,5.5%,6%,6.5%,7%,7.5%,8%,8.5%,9%,9.5%,10%, or any number thereof, based on the total volume of the first positive electrode active material film layer.
In some embodiments, the first positive electrode active material film layer has a porosity of 8% -25%, and the first positive electrode active material film layer may have a porosity of 10% -18%. On the basis of the porosity of the first positive electrode active material film layer, the porosity of the positive electrode plate is improved in the process of filling liquid into a battery containing the positive electrode plate and subsequent charge-discharge cycles, so that the dynamic performance of the battery in use is improved. In some embodiments, the first positive electrode active material film layer has a porosity of 10% -15%, and after the secondary battery including the positive electrode sheet is charged and discharged, the first positive electrode active material film layer has a porosity of 15% -25%.
In some embodiments, the second positive electrode active material film layer includes a pore former, wherein the mass percent of the pore former in the second positive electrode active material film layer is less than the mass percent of the pore former in the first positive electrode active material film layer. The mass percentage of the pore-forming agent in the second positive electrode active material film layer is smaller than that of the pore-forming agent in the first positive electrode active material film layer, so that the porosity of the first positive electrode active material film layer is larger than that of the second positive electrode active material film layer, and the positive electrode plate has gradient porosity. The first positive electrode active material film layer has more pore distribution and reduced compactness, and can improve the electrolyte wettability of the surface, thereby reducing the ion impedance of the positive electrode plate.
In the technical scheme, the porosity represents the percentage of the pore volume in the first positive electrode active material film layer to the total volume of the first positive electrode active material film layer. The porosity of the positive electrode plate can be obtained through a porosity measuring instrument. As an example, weighing a positive electrode plate sample with a certain mass, and removing a first positive electrode active material film layer, measuring the thickness of the sample by using a ten-thousandth ruler respectively, and obtaining the apparent volume V1 of the sample according to the surface area and the thickness of the sample; placing a sample in an AccuPyc II 1340 type full-automatic true density tester, sealing a test system, introducing nitrogen according to a program, detecting the gas pressure in a sample chamber and an expansion chamber, and calculating the true volume V according to Boyle's law (PV=C, wherein P is the pressure of the gas, V is the volume of the gas, and C is a constant) 2 The method comprises the steps of carrying out a first treatment on the surface of the Then according to s= (V 1 -V 2 )/V 1 The x 100% yields the porosity of the first positive electrode active material film layer.
In some embodiments, the pore former has an average particle size Dv50 of 1 to 10 μm. In some embodiments, the pore former is particulate. The pore-forming agent with the particle size exists in the first positive electrode active material film layer, so that on one hand, the compaction density of the first positive electrode active material film layer when not in use can be ensured, and on the other hand, the pore-forming agent is dissolved in electrolyte in the process of filling liquid into a battery containing the positive electrode plate and then carrying out charge-discharge circulation,the material which can not damage the battery performance can not be released, and the structure of the first positive electrode active material film layer can be maintained, so that the positive electrode plate has higher porosity and ionic resistance. The average particle diameter Dv50 of the pore-forming agent may be the average particle diameter of the pore-forming agent when used as a slurry for producing a positive electrode active material film layer. Average pore-forming agentParticle sizeDistribution ofDv50In a manner known in the art, whereinParticle sizeDistribution ofDv50Also known as averageParticle sizeOr median valueParticle sizeRepresenting 50% of the volume distribution of the first positive electrode active material particles and the likeParticle sizeThe method comprises the steps of carrying out a first treatment on the surface of the Each of the aboveParticle sizeThe distribution may be determined using instrumentation and methods well known in the art. For example, it may be conveniently measured using a laser particle size analyzer, such as the Mastersizer model 3000 laser particle size analyzer available from Markov instruments, UK.
In some embodiments, the thickness ratio of the first positive electrode active material film layer and the second positive electrode active material film layer is 1: (1-5). By controlling the thickness ratio of the first positive electrode active material film layer to the second positive electrode active material film layer in the above range, on one hand, the porosity of the positive electrode plate can be effectively ensured, on the other hand, the compaction density of the positive electrode plate active material film layer can be effectively ensured, the ion resistance can be reduced on the premise of ensuring the energy density, and the dynamic performance of the secondary battery comprising the positive electrode plate can be improved.
In some embodiments, the second positive electrode active material film layer has a thickness of 15 to 50 μm.
In some embodiments, the first positive electrode active material film layer has a thickness of 5 to 25 μm.
In some embodiments, the first positive electrode active material film layer includes first positive electrode active particles; the second positive electrode active material film layer includes second positive electrode active particles; the ratio of the average particle diameter Dv50 of the first positive electrode active particles to the average particle diameter Dv50 of the second positive electrode active particles was 1: (0.8-1.2). By controlling the ratio of the average particle diameter Dv50 of the first positive electrode active particles to the second positive electrode active particles, the first positive electrode active material film layer and the second positive electrode active material film layer can have different compaction densities and different porosities, and the effects of reducing resistance and improving dynamic performance are realized.
In some embodiments, the first positive electrode active particles have an average particle diameter Dv50 of 2-15 μm.
In some embodiments, the average particle diameter Dv50 of the second positive electrode active particles is 2-15 μm.
In some embodiments, a method of preparing a positive electrode sheet includes:
providing a first slurry and a second slurry for forming a first positive electrode active material film layer and a second positive electrode active material film layer, respectively, wherein the first slurry comprises a pore-forming agent, and the pore-forming agent comprises at least one of lithium salt or a solid-phase organic compound; the lithium salt comprises a lithium bisfluorosulfonyl imide salt, lithium bisoxalato borate, lithium difluorooxalato borate, lithium difluorodioxaato phosphate, lithium difluorophosphate, or a combination thereof; the solid-phase organic compound is selected from one or more of vinyl sulfate, vinyl sulfite, phosphite and adiponitrile;
coating the first sizing agent and the second sizing agent on the surface of the same side of the positive electrode current collector respectively;
and drying the first slurry and the second slurry coated on the positive electrode current collector to form a first positive electrode active material film layer and a second positive electrode active material film layer, so as to obtain the positive electrode plate, wherein the second positive electrode active material film layer is positioned between the positive electrode current collector and the first positive electrode active material film layer.
According to the embodiment of the application, the pore-forming agent is added into the first slurry, and the pore-forming agent is granular and does not react with substances in the slurry when the positive electrode plate is prepared, and is dissolved or oxidized and dissolved in the process of filling liquid and charging and discharging the positive electrode plate, so that the gap of the first positive electrode active material film layer forming the dispersed porous structure is improved, the ion impedance is reduced, and the dynamic performance of the secondary battery is improved.
In some embodiments, the first and second positive electrode active material film layers have a compacted density of 3.3 to 4.4g/cm, respectively 3 The method comprises the steps of carrying out a first treatment on the surface of the Optionally, a first positive electrode active material film layer and a second positive electrode active material film layerThe compaction density of the two positive electrode active material film layers is 3.4-4.3 g/cm respectively 3 . The compaction density of the positive electrode active material film layer is controlled, so that the structure and the performance of the positive electrode active film layer are ensured, the porosity of the positive electrode plate is improved, and the dynamic performance in use is improved. In some embodiments, the positive electrode active particles are lithium cobaltate, and the compacted density of the first positive electrode active material film layer and the second positive electrode active material film layer is 4.1g/cm 3 ～4.4g/cm 3 . In some embodiments, the positive electrode active particles are lithium nickel cobalt manganese oxide, and the compacted density of the first positive electrode active material film layer and the second positive electrode active material film layer is 3.4g/cm 3 ～3.7g/cm 3 。
In the present application, the positive electrode current collector is not limited, and a metal foil, a porous metal plate, or a composite current collector 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 material. The composite current collector may be formed by forming a metal material (copper, copper 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.). As one example, the current collector is aluminum foil.
In some embodiments, the first and second positive electrode active material film layers each include a conductive agent. The conductive agent may also be a conductive agent commonly used in the art, and the specific type is not particularly limited. For example, the conductive agent may include one or more of conductive carbon black, acetylene black, carbon nanotubes, carbon fibers, ketjen black, and graphene.
Secondary battery
A second aspect of the embodiments of the present application provides a secondary battery, including: the positive electrode sheet, the negative electrode sheet, the electrolyte and the separator which are spaced between the positive electrode sheet and the negative electrode sheet of the first aspect.
It is understood that the secondary battery of the present application can achieve the beneficial effects of any of the above embodiments of the positive electrode sheet of the present application.
The type of the secondary battery is not particularly limited in the present application, and for example, the secondary battery may be a lithium ion battery, a sodium ion battery, or the like.
The secondary battery includes an electrolyte. In some embodiments, the electrolyte comprises a carbonate comprising one or more of ethylene carbonate, propylene carbonate, diethyl carbonate, or dimethyl carbonate. The carbonic ester can be dissolved or oxidized and dissolved with the pore-forming agent in the positive electrode active material film layer in the positive electrode plate to form an SEI film, so that the pore-forming agent is separated from the positive electrode active material film layer, and the porosity of the positive electrode plate is improved.
In some embodiments, the mass content of carbonate in the electrolyte ranges from 20% to 90%. When the mass content of the first compound in the electrolyte is in the above range, the pore-forming agent in the positive electrode sheet can be completely dissolved or oxidatively dissolved.
In some embodiments, the ratio of the initial content of the pore-forming agent in the first positive electrode active material film layer to the content of the pore-forming agent in the first positive electrode active material film layer after 20 charge and discharge of the secondary battery is 1 (0.01-0.2).
The initial content of the pore-forming agent in the first positive electrode active material film layer can be understood as: content of pore-forming agent in secondary battery at the time of detection. Generally, the number of cycles of the secondary battery is 1 to 20; the content of the secondary battery may be at the time of formation or may be at the time of charging and discharging a small number of times immediately after purchase. The detection content may be detected at times other than 1 to 20 times of the cycle.
The content of the pore-forming agent in the first positive electrode active material film layer after 20 charge and discharge of the secondary battery can be understood as: after about 20 charges and discharges of the same batch or type of secondary batteries with the initial content of the pore-forming agent in the positive electrode active material film layer, the mass content of the pore-forming agent in the first positive electrode active material film layer is detected.
According to the embodiment of the application, through the ratio of the initial content of the pore-forming agent in the first positive electrode active material film layer to the content of the pore-forming agent in the first positive electrode active material film layer after the secondary battery is charged and discharged for 20 times, it can be seen that the pore-forming agent is gradually dissolved or oxidized and dissolved in the electrolyte in the process of filling liquid and charging and discharging the positive electrode pole piece, and the porosity of the positive electrode pole piece is improved by adding the pore-forming agent, so that the dynamic performance of the secondary battery is improved.
In some embodiments, the element B is included in an amount of 0.1% to 5% based on the total weight of the first positive electrode active material film layer. When the pore-forming agent contained in the fresh positive electrode active material film layer is lithium difluoroborate (LiODFB), the positive electrode plate can detect the boron element with the content in the positive electrode active material film layer of the positive electrode plate after charge and discharge.
In some embodiments, the S element is included in an amount of 0.1% to 5% based on the total weight of the first positive electrode active material film layer. When the pore-forming agent contained in the fresh positive electrode active material film layer is vinyl sulfate (DTD), the positive electrode plate can detect the elements with the content in the positive electrode active material film layer of the positive electrode plate after charge and discharge.
In some embodiments, the B element is included in an amount of 0.1% to 5% and the S element is included in an amount of 0.1% to 5% based on the total weight of the first positive electrode active material film layer. When the pore-forming agent contained in the fresh positive electrode active material film layer is ethylene sulfate (DTD) and lithium difluorooxalato borate (LiODFB), the boron element and the sulfur element with the content can be detected in the first positive electrode active material film layer of the positive electrode plate in the liquid injection and positive electrode charging and discharging processes.
In some embodiments, the secondary battery may include an outer package. The outer package may be used to encapsulate the electrode assembly and electrolyte described above. For example, fig. 6 shows a secondary battery 5 of a square structure as one example.
In some embodiments, referring to fig. 7, the overpack may include a housing 51 and a cap assembly 53. The housing 51 may include a bottom plate and a side plate connected to the bottom plate, where the bottom plate and the side plate enclose a receiving chamber. The housing 51 has an opening communicating with the accommodating chamber, and the top cover assembly 53 can be provided to cover the opening to close the accommodating chamber. The positive electrode sheet, the negative electrode sheet, and the separator may be formed into the electrode assembly 12 through a winding process or a lamination process. The electrode assembly 52 is packaged in the receiving chamber. The electrolyte is impregnated in the electrode assembly 52. The number of electrode assemblies 52 included in the secondary battery 5 may be one or more, and those skilled in the art may select according to specific practical requirements.
In some embodiments, the outer package of the secondary battery may be a hard shell, such as a hard plastic shell, an aluminum shell, a steel shell, or the like. The exterior package of the secondary battery may also be a pouch type pouch, for example. The soft bag can be made of one or more of polypropylene (PP), polybutylene terephthalate (PBT), polybutylene succinate (PBS), etc.
The shape of the secondary battery is not particularly limited in the present application, and may be a flat body, a rectangular parallelepiped, or other shapes.
In some embodiments, a negative electrode sheet, a separator, and an electrolyte are also included.
[ negative electrode plate ]
The type of the negative electrode plate is not particularly limited, and any known negative electrode plate with good performance can be selected.
In some embodiments, the negative electrode tab comprises: the negative electrode current collector and the negative electrode active material layer include a negative electrode active material, a binder, and a conductive agent.
According to embodiments of the present application, the negative electrode current collector may be a metal foil or a porous metal plate, such as a foil or a porous plate of a metal such as copper, nickel, titanium, iron, or an alloy thereof. Among them, the anode active material may use one or more of a carbonaceous material, a metal compound that can be alloyed with lithium, a metal oxide that can be doped and undoped with lithium, and a composite including a metal compound and a carbonaceous material. As an example, the carbonaceous material may include one or more of artificial graphite, natural graphite, graphitized carbon fiber, and amorphous carbon; the metal compound which can be alloyed with lithium may include one or more of silicon (Si), aluminum (Al), tin (Sn), lead (Pb), zinc (Zn), bismuth (Bi), indium (In), magnesium (Mg), gallium (Ga), cadmium (Cd), si alloy, sn alloy, or Al alloy; can be doped with And the metal oxide that is not doped with lithium may include SiO v (0<v<2)、SnO 2 One or more of vanadium oxide and lithium vanadium oxide; the composite comprising the metal compound and the carbonaceous material may comprise a Si-C composite and/or a Sn-C composite. These negative electrode active materials may be used alone or in combination of two or more.
The binder and the conductive agent may be selected with reference to the embodiment of the first aspect, and the preparation method thereof is similar to the above-described method of preparing the positive electrode sheet.
[ MEANS FOR PROBLEMS ]
The diaphragm is arranged between the anode and the cathode, mainly plays a role in preventing the anode from being short-circuited, and can enable active ions to pass through. The type of separator is not particularly limited, and any known porous separator having good chemical stability and mechanical stability may be used.
In some embodiments, the material of the separator may be one or more selected from glass fiber, non-woven fabric, polyethylene, polypropylene, polyvinylidene fluoride, but not limited to these. Optionally, the material of the separator may include polyethylene and/or polypropylene. The separator may be a single-layer film or a multilayer composite film. When the separator is a multilayer composite film, the materials of the layers are the same or different. In some embodiments, a ceramic coating, a metal oxide coating may also be provided on the separator.
[ electrolyte ]
The electrolyte serves to conduct active ions between the positive electrode and the negative electrode. The electrolyte that can be used in the secondary battery of the present application may be an electrolyte known in the art.
In some embodiments, the electrolyte may include an organic solvent, an electrolyte salt, and optional additives, and the types of the organic solvent, the lithium salt, and the additives are not particularly limited and may be selected according to the needs.
In some embodiments, the secondary battery is a lithium ion battery, and the electrolyte salt may include a lithium salt. As an example, the lithium salt includes, but is not limited to LiPF 6 Lithium hexafluorophosphate, liBF 6 (IV)Lithium fluoroborate), liClO 4 (lithium perchlorate), liFeSI (lithium bis-fluorosulfonyl imide), liTFSI (lithium bis-trifluoromethanesulfonyl imide), liTFS (lithium trifluoromethanesulfonate), liDFOB (lithium difluorooxalato borate), liBOB (lithium bisoxalato borate), liPO 2 F 2 At least one of (lithium difluorophosphate), liDFOP (lithium difluorodioxalate phosphate) and LiTFOP (lithium tetrafluorooxalate phosphate). The lithium salts may be used singly or in combination of two or more.
In some embodiments, the secondary battery is a sodium ion battery, and the electrolyte salt may include a sodium salt. As an example, the sodium salt may be selected from NaPF 6 、NaClO 4 、NaBCl 4 、NaSO 3 CF 3 Na (CH) 3 )C 6 H 4 SO 3 At least one of them.
In some embodiments, the organic solvent includes, by way of example, but is not limited to at least one of Ethylene Carbonate (EC), propylene Carbonate (PC), ethylmethyl carbonate (EMC), diethyl carbonate (DEC), dimethyl carbonate (DMC), dipropyl carbonate (DPC), methylpropyl carbonate (MPC), ethylpropyl carbonate (EPC), butylene Carbonate (BC), fluoroethylene carbonate (FEC), methyl Formate (MF), methyl Acetate (MA), ethyl Acetate (EA), propyl Acetate (PA), methyl Propionate (MP), ethyl Propionate (EP), propyl Propionate (PP), methyl Butyrate (MB), ethyl Butyrate (EB), 1, 4-butyrolactone (GBL), sulfolane (SF), dimethylsulfone (MSM), methylsulfone (EMS), and diethylsulfone (ESE). The organic solvents may be used singly or in combination of two or more. Alternatively, two or more of the above organic solvents are used simultaneously.
In some embodiments, the additives may include negative film-forming additives, positive film-forming additives, and may also include additives that improve certain properties of the battery, such as additives that improve the overcharge performance of the battery, additives that improve the high or low temperature performance of the battery, and the like.
As an example, the additive includes, but is not limited to, at least one of fluoroethylene carbonate (FEC), vinylene Carbonate (VC), vinyl Ethylene Carbonate (VEC), vinyl sulfate (DTD), propylene sulfate, ethylene Sulfite (ES), 1, 3-Propane Sultone (PS), 1, 3-Propane Sultone (PST), sulfonate cyclic quaternary ammonium salt, succinic anhydride, succinonitrile (SN), adiponitrile (AND), tris (trimethylsilane) phosphate (TMSP), tris (trimethylsilane) borate (TMSB).
The electrolyte may be prepared according to a conventional method in the art. For example, the organic solvent, electrolyte salt, and optional additives may be uniformly mixed to obtain the electrolyte. The order of addition of the materials is not particularly limited, and for example, electrolyte salt and optional additives are added into an organic solvent and mixed uniformly to obtain an electrolyte; or adding electrolyte salt into the organic solvent, and then adding optional additives into the organic solvent to be uniformly mixed to obtain the electrolyte.
Electronic device
A third aspect of embodiments of the present application provides an electronic device including the secondary battery of the second aspect.
The secondary battery may be used as a power source of the electronic device and may also be used as an energy storage unit of the electronic device.
The electronic apparatus of the present application is not particularly limited, and may be applied to any electronic device known in the art. In some embodiments, the electronic device may include, but is not limited to, a notebook computer, a pen-input computer, a mobile computer, an electronic book player, a portable telephone, a portable facsimile machine, a portable copier, a portable printer, a headset, a video recorder, a liquid crystal television, a portable cleaner, a portable CD-player, a mini-compact disc, a transceiver, an electronic notepad, a calculator, a memory card, a portable audio recorder, a radio, a backup power source, a motor, an automobile, a motorcycle, a power assisted bicycle, a lighting fixture, a toy, a game machine, a clock, an electric tool, a flash light, a camera, a household large-sized battery, a lithium ion capacitor, and the like.
The electronic device as another example may be a cell phone, a tablet computer, a notebook computer, or the like. For example, fig. 8 shows an electronic apparatus as one example. The electronic device is generally required to be thin and lightweight, and a secondary battery can be used as a power source.
Examples
The present disclosure is more particularly described in the following examples that are intended as illustrations only, since various modifications and changes within the scope of the present disclosure will be apparent to those skilled in the art. Unless otherwise indicated, all parts, percentages, and ratios reported in the examples below are on a mass basis, and all reagents used in the examples are commercially available or were obtained synthetically according to conventional methods and can be used directly without further treatment, as well as the instruments used in the examples.
Examples 1 to 3
1. Preparation of positive electrode plate
Mixing conductive carbon black and polyvinylidene fluoride (PVDF) according to a certain proportion, and adding N-methyl pyrrolidone (NMP) to prepare conductive glue solution (solid content 7%). After the mixing is completed, adding the positive electrode active material lithium cobaltate, and continuously stirring under the action of a vacuum stirrer until the system is uniform, thereby obtaining the positive electrode slurry with the solid content of 75%. The mass ratio of each component is as follows: positive electrode active material: conductive carbon tube: and (2) a binder: pore former = 95:1:2:2, preparing a first slurry.
Mixing conductive carbon black and a binder polyvinylidene fluoride (PVDF) according to a certain proportion, and adding N-methyl pyrrolidone (NMP) to prepare conductive glue solution (solid content 7%). After the mixing is completed, adding the positive electrode active material lithium cobaltate, and continuously stirring under the action of a vacuum stirrer until the system is uniform, thereby obtaining the positive electrode slurry with the solid content of 75%. The mass ratio of each component is as follows: positive electrode active material: conductive carbon tube: binder = 97:1:2, preparing second slurry.
And coating the first positive electrode slurry and the second slurry on a positive electrode current collector, drying, and cold pressing to obtain a positive electrode plate containing a first positive electrode active material film layer and a second active material film layer, wherein the first positive electrode active material film layer is positioned on the surface of the positive electrode plate, and then cutting and welding the electrode lugs to obtain the positive electrode plate. The positive electrode sheet was set according to the conditions of the following examples and comparative examples, as shown in tables 1-2, so as to have the corresponding compositions and parameters.
2. Preparation of negative electrode plate
Mixing artificial graphite, styrene-butadiene rubber and sodium carboxymethyl cellulose with deionized water and an auxiliary agent according to the mass ratio of 96-2%, and uniformly stirring to obtain the negative electrode slurry. The negative electrode slurry was coated on a copper foil 6 μm thick. Drying, cold pressing, cutting and welding the tab to obtain the negative electrode plate.
3. Preparation of electrolyte diethyl carbonate (DEC), ethylene Carbonate (EC) and Propylene Carbonate (PC) (weight ratio 1:1:1) were mixed under dry argon atmosphere and LiPF was added thereto 6 Uniformly mixing to form a basic electrolyte, wherein the LiPF 6 The concentration of (C) was 1.15mol/L.
4. Preparation of a separator film
A porous polymer film of Polyethylene (PE) was used as a separator.
5. Preparation of lithium ion batteries
And winding the obtained positive pole piece, the isolating film and the negative pole piece in sequence, and placing the wound positive pole piece, the isolating film and the negative pole piece in an outer packaging foil to leave a liquid injection port. And (3) pouring electrolyte from the liquid pouring port, packaging, and performing the working procedures of formation, capacity and the like to obtain the lithium ion battery.
Comparative examples 1 to 3
Comparative examples 1 to 3 differ from example 1 in that: the types and contents of pore formers were varied as shown in Table 1.
Examples 2 to 3
Examples 2-3 differ from example 1 in that: the pore-forming agent content was varied as shown in table 1;
examples 4 to 6
Examples 4-6 differ from example 1 in that: the types of pore formers were varied as shown in table 1.
Examples 7 to 9
Examples 7-9 differ from example 1 in that: the thicknesses of the first positive electrode active material film layer containing the pore-forming agent and the second positive electrode active material film layer containing no pore-forming agent are different, as shown in table 1.
Examples 12 to 15
Examples 12 to 15 differ from example 1 in that: the types and contents of pore formers were different as shown in Table 1.
Test part
Morphology observation:
the film layer of the positive electrode active material in the fresh electrode sheet in example 2 was observed by a scanning electron microscope or a microscope: as shown in fig. 3: FIG. 3 shows the pore-forming agent distribution of a fresh pole piece containing 5% pore-forming agent, as seen at 500 times, with the black areas being areas of the pore-forming agent, illustrating the pore-forming agent distribution around and in intimate association with the primary particles; fig. 4 is a picture of the surface of the positive electrode active material film layer of the electrode sheet observed at 5000 times, and it can be seen that pore-forming agents near the active main material are dissolved after soaking and charging and discharging, pores exist among particles, which illustrates that the pore-forming agents are oxidized and dissolved in electrolyte in charging and discharging to form vacancies, and the porosity of the positive electrode active material film layer is improved.
The cross-sectional view of the positive electrode sheet after charge-discharge cycle in example 2 is shown in fig. 5 when observed under high magnification by a scanning electron microscope: the section of the positive electrode sheet observed at 2000 times in fig. 5 can be seen that the pore-forming agent near the active main material of the upper layer is dissolved after soaking and charging and discharging, macropores exist among particles, which indicates that the pore-forming agent of the upper layer is oxidized and dissolved in electrolyte in charging and discharging to form vacancies, and the porosity of the film layer of the positive electrode active material is improved.
1. The method for testing the element content in the positive electrode plate comprises the following steps:
the method for testing the element content in the pole piece adopts an SEM (scanning electron microscope) and an EDS (electron microscope) energy spectrometer to test the element distribution and the element content in a cross section area, and comprises the following testing steps:
(1) Liquid injection front pole piece: directly testing according to the steps (2) - (6); and (3) filling the liquid into the pole piece: soaking with high-purity DMC for 24 hours, washing off electrolyte residues, replacing fresh DMC every 8 hours, vacuumizing and airing in a vacuum box at room temperature after soaking for 12 hours until DMC residues are absent on the surface, and then performing the tests of steps (2) - (6);
(2) The cross section of the pole piece is polished neatly by a plasma polishing instrument;
(3) SEM selection magnification is 100-2000 times, and a coating main body is covered in a visual field;
(4) EDS distribution analysis is carried out on the area in the visual field; selecting specified elements for distribution analysis;
(5) Outputting element content data, and confirming the content of each element;
(6) Repeating the steps (2) - (5) for 3 times, adding parallel sample test, and taking the average value as the element content;
2. pole piece compaction density testing method
Compacted density of positive electrode active material layer = positive electrode active material layer mass per unit area (g/cm) 2 ) Positive electrode active material layer thickness (cm). The mass of the positive electrode active material layer per unit area can be weighed by a balance, and the thickness of the positive electrode active material layer can be measured by a ten-thousandth ruler. The results are shown in tables 1 and 2.
3. The method for testing the porosity of the positive electrode plate comprises the following steps:
the method for testing the porosity of the pole piece refers to the following steps: GT/B24586 determination of apparent Density, true Density and porosity of iron ore, test procedure of Density method for measuring porosity of Pole piece:
(1) Directly testing the fresh pole pieces in the steps (2) - (6); and (3) filling the liquid into the pole piece: soaking the raw materials in high-purity DMC for 24 hours, wherein fresh DMC is replaced every 8 hours, vacuumizing and drying the soaked raw materials in a vacuum box at 85 ℃ for 8 hours, and then performing the tests from the step (2) to the step (6);
(2) Punching small wafers with the diameter of 10mm on the sample pole pieces by using a sheet punching machine, wherein the ports of the wafers are neat, and the number of the wafers is more than or equal to 40pcs;
(3) Measuring the thickness of the small wafer by a ten-thousandth ruler, and taking an average value;
(4) Placing a sample in a cavity of the tester, and opening test software to perform operation test;
(5) Outputting an operation report, and confirming the porosity data;
(6) Repeating the steps (2) - (5) for 3 times, adding a parallel sample test, and taking an average value of the porosity. The results are shown in tables 1 and 2.
4. The method for testing the porosity of the first active material film layer and the second active material film layer in the positive electrode plate comprises the following steps:
the method for testing the porosity of the upper and lower layers of the pole piece adopts an SEM (scanning electron microscope) method for testing the section area, and comprises the following testing steps:
weighing a positive pole piece sample with a certain mass, measuring the thickness of the sample by using a ten-thousandth ruler, and obtaining the apparent volume V1 of the sample according to the surface area and the thickness of the sample; placing a sample in an AccuPyc II 1340 type full-automatic true density tester, sealing a test system, introducing nitrogen according to a program, detecting the gas pressure in a sample chamber and an expansion chamber, and calculating the true volume V according to Boyle's law (PV=C, wherein P is the pressure of the gas, V is the volume of the gas, and C is a constant) 2 The method comprises the steps of carrying out a first treatment on the surface of the Then according to s= (V 1 -V 2 )/V 1 Obtaining the porosity of the positive electrode active material film layer by x 100%;
soaking and dissolving the pole piece for 24 hours at the constant temperature of 150 ℃, then vacuum drying the pole piece, and then testing the porosity of the soaked pole piece by the method in the reference (1); combining the porosity data before and after soaking with the corresponding coating thickness, and calculating the respective porosities of the first active material film layer and the second active material film layer; the results are shown in tables 1 and 2.
5. Mass content detection of pore-forming agent
Can be obtained by ultrasonic separation and a test method of soaking, heating and dissolving. Weighing a positive pole piece sample with a certain mass, ultrasonically rotating and separating an active layer by using N-methyl pyrrolidone (NMP), drying and grinding active slurry into powder with a mass of m0, soaking the powder for 24 hours at a high temperature of 150 ℃ by using EC/DMC and other solutions, drying the powder again, and measuring the difference between the mass of the powder and the mass of the powder to be the mass m1 of the pore-forming agent; after removing the positive electrode current collector, weighing the mass m0 of a positive electrode active material film sample, soaking the powder which contains the carbon conductive agent and is dried again with the mass content of m1/m0 in concentrated sulfuric acid, and filtering the filtered filter residue to obtain a binder and conductive carbon m2; then the temperature is raised to 800 ℃ by utilizing TG to decompose the binder, and the rest is conductive carbon m3, so that the mass content of each substance is calculated: pore-forming agent m1, conductive agent m3, binder m2-m3, positive electrode active material m0-m1-m2.
6. 50% SOC cell DC internal resistance detection
Disassembling the secondary battery in a glove box, assembling the original positive electrode, the negative electrode and the diaphragm into a button battery, then re-injecting fresh electrolyte, wherein the type of the injected electrolyte is the same as that described in the application, and standing for 4 hours in a high-low temperature box at 25 ℃; discharging for 2.5h at 0.2C to a specified voltage (3.95V for lithium cobalt oxide and 3.6V for lithium manganese oxide for positive electrode active material and 3.0V for lithium iron phosphate for positive electrode active material), then standing for 10min, and discharging for 1s at 1C constant current; and detecting relevant parameters in the environment temperature of 25 ℃, and calculating the direct current internal resistance of the battery cell corresponding to the 50% SOC state of the secondary battery.
7. Cell DC internal resistance after 20 times of battery charge and discharge
Disassembling a secondary battery in a glove box, assembling an original positive electrode, an original negative electrode and an original diaphragm into a button battery, then re-injecting fresh electrolyte, wherein the types of the injected electrolyte are the same as those of the button battery, preparing a plurality of button batteries with the same system, performing constant-current charging with 0.5C current to a set value (the voltage of lithium cobaltate is 4.5V for the positive electrode active material, the voltage of lithium nickel cobalt manganate and lithium manganate is 4.2V for the positive electrode active material, the voltage of lithium iron phosphate is 3.6V for the positive electrode active material), changing into constant-voltage charging to a cut-off current of 0.05C, standing for 10min, discharging a specified voltage (the voltage of lithium cobaltate, lithium nickel cobalt manganate, lithium manganate or the mixture thereof is 3.0V for the positive electrode active material, the voltage of lithium iron phosphate is 2.5V for the positive electrode active material) at the environment temperature of 25 ℃, and standing for 5min;
then, circulating part of the battery cells for 20 times to obtain treated battery cells according to the flow;
and detecting relevant parameters in the environment temperature of 25 ℃ according to the 50% SOC battery cell direct current internal resistance detection, and obtaining the battery cell direct current internal resistance corresponding to the battery cell 50% SOC state after 20 times of circulation.
8. Kinetic performance test:
1.5C rate charge capacitance ratio
The lithium ion batteries of examples and comparative examples were tested. Placing the battery in a constant temperature box at 25 ℃ for 120min, charging to 4.5V at a constant current of 0.2C, charging to 0.025C at a constant voltage, standing for 5min, discharging to 3V at 0.2C, recording a constant current charging capacity C2 of 02C, and standing for 5min. After charging again to 4.5V at a constant current of 1.5C, charging again to 0.025C at a constant voltage, and after standing for 5min, discharging to 3V at 0.2C, a constant current charging capacity C3 of 1.5C was recorded. 1.5C constant current Rate charging Capacity ratio = C3/C2×100%
9. And (3) testing the cycle performance: the batteries prepared in the examples and the comparative examples are placed in a constant temperature test box at 25 ℃ and kept stand for 30 minutes, so that the lithium ion battery reaches constant temperature. Constant current charging was performed at 0.5C to 4.5V, constant voltage charging was performed at 0.025C current, and the mixture was allowed to stand for 5 minutes, and constant current discharging was performed at 0.5C to 3.0V, which was recorded as an initial discharge capacity C0. With this step, 100 cycles were repeated, the discharge capacity C1 after 100 cycles was recorded, and the capacity retention rate of the battery was calculated for 100 cycles.
Circulation capacity retention = C1/c0×100%
From the test results shown in tables 1 and 2, the porosity of the pore-forming agent added in the examples was increased, the impedance (DCR) was decreased, the dynamic properties including ploidy were improved, and the cycle performance was slightly improved.
In example 1, the upper pore-forming agent was added as compared with comparative example 1, and the porosity was increased, the direct current resistance was decreased, and the rate performance was improved.
In example 1, compared with examples 2 to 3, only the amount of pore-forming agent added was different, and the other was the same, and it can be seen that the porosity, dc resistance, rate capability, and the like were all related to the amount added.
In example 1, compared with examples 4 to 6, only the types of pore-forming agents were different, and all others were the same, and it can be seen that the porosity, the direct current resistance, the rate capability, and the like were all related to the types of incorporation.
Compared with examples 10-12, the coating weights and thicknesses of the upper and lower layers are different, and the other layers are the same, so that the porosity, the direct current impedance, the rate capability and the like are all related to the content of the pore-forming agent in the first active material film layer and the second active material film layer.
In example 1, compared with examples 13 to 15, the types of the incorporated pore-forming agents were mixed pore-forming agents, and the other types were the same, and it can be seen that the porosity, the direct current resistance, the rate capability and the like were all related to the types and the contents of the pore-forming agents.
The present application is not limited to the above embodiment. The above embodiments are merely examples, and embodiments having substantially the same configuration and the same effects as those of the technical idea within the scope of the present application are included in the technical scope of the present application. Further, various modifications that can be made to the embodiments and other modes of combining some of the constituent elements in the embodiments, which are conceivable to those skilled in the art, are also included in the scope of the present application within the scope not departing from the gist of the present application.
TABLE 1
TABLE 2
Claims (14)
1. A positive electrode sheet, characterized by comprising:
a positive electrode current collector; and
a first positive electrode active material film layer and a second positive electrode active material film layer, wherein the first positive electrode active material film layer is arranged on one side of the positive electrode current collector, the second positive electrode active material film layer is arranged between the positive electrode current collector and the first positive electrode active material film layer,
wherein the first positive electrode active material film layer comprises a pore-forming agent, and the pore-forming agent comprises at least one of lithium salt or solid-phase organic compound; the lithium salt comprises one or more of lithium bis (fluorosulfonyl) imide, lithium bis (oxalato) borate, lithium difluoro (oxalato) phosphate and lithium difluoro (oxalato) phosphate; the solid-phase organic compound comprises one or more of vinyl sulfate, vinyl sulfite, phosphite, adiponitrile or the like.
2. The positive electrode sheet of claim 1, wherein the first positive electrode active material film layer comprises 0.01% -5% of the pore-forming agent, based on the total weight of the first positive electrode active material film layer.
3. The positive electrode sheet of claim 1, wherein the first positive electrode active material film layer comprises 0.5% -2% of the pore-forming agent, based on the total weight of the first positive electrode active material film layer.
4. The positive electrode sheet according to any one of claims 1 to 3, wherein the second positive electrode active material film layer includes the pore-forming agent, wherein a mass percentage of the pore-forming agent in the second positive electrode active material film layer is smaller than a mass percentage of the pore-forming agent in the first positive electrode active material film layer.
5. The positive electrode sheet according to any one of claims 1 to 3, wherein the pore-forming agent has an average particle diameter Dv50 of 1 to 10 μm; and/or the number of the groups of groups,
the pore-forming agent is granular.
6. The positive electrode sheet according to claim 1, wherein a thickness ratio of the first positive electrode active material film layer and the second positive electrode active material film layer is 1: (1-5).
7. The positive electrode sheet according to claim 6, wherein the thickness of the second positive electrode active material film layer is 15-50 μm; and/or the number of the groups of groups,
the thickness of the first positive electrode active material film layer is 5-25 mu m.
8. The positive electrode sheet according to claim 6 or 7, wherein the first positive electrode active material film layer includes first positive electrode active particles; the second positive electrode active material film layer includes second positive electrode active particles; the ratio of the average particle diameter Dv50 of the first positive electrode active particles to the average particle diameter Dv50 of the second positive electrode active particles is 1: (0.8-1.2).
9. The positive electrode sheet according to claim 8, wherein the average particle diameter Dv50 of the first positive electrode active particles is 2-15 μm; and/or the number of the groups of groups,
the average particle diameter Dv50 of the second positive electrode active particles is 2-15 μm.
10. A secondary battery, comprising: the positive electrode sheet, negative electrode sheet, electrolyte, and separator film of any one of claims 1-9, spaced between the positive electrode sheet and the negative electrode sheet.
11. The secondary battery according to claim 10, wherein the electrolyte comprises a carbonate ester, the carbonate ester comprising one or more of ethylene carbonate, propylene carbonate, diethyl carbonate, and dimethyl carbonate.
12. The secondary battery according to claim 11, wherein the mass content of the carbonate in the electrolyte is in the range of 20% to 90%.
13. The secondary battery according to any one of claims 10 to 12, wherein a ratio of an initial content of the pore-forming agent in the first positive electrode active material film layer to a content of the pore-forming agent in the first positive electrode active material film layer after 20 charge and discharge of the secondary battery is 1 (0.01 to 0.2).
14. An electronic device comprising the secondary battery according to any one of claims 10 to 13.
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116646470A (en) * | 2023-07-18 | 2023-08-25 | 宁德时代新能源科技股份有限公司 | Positive electrode plate, preparation method of positive electrode plate, battery and electric equipment |
| CN117558921A (en) * | 2024-01-12 | 2024-02-13 | 宁德时代新能源科技股份有限公司 | Electrode manufacturing method, battery, and electricity using device |
| CN117558921B (en) * | 2024-01-12 | 2024-05-28 | 宁德时代新能源科技股份有限公司 | Electrode manufacturing method, battery, and electricity using device |
Citations (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20100015327A1 (en) * | 2008-07-21 | 2010-01-21 | Battelle Memorial Institute | Methods and compositions for preparing porous electrodes |
| US20150357626A1 (en) * | 2014-06-05 | 2015-12-10 | 24M Technologies, Inc. | Porous semi-solid electrode and methods of manufacturing the same |
| US20190237731A1 (en) * | 2018-02-01 | 2019-08-01 | Samsung Electronics Co., Ltd. | Porous film, separator including porous film, electrochemical device including porous film, and method of preparing porous film |
| CN110224112A (en) * | 2018-11-07 | 2019-09-10 | 山东华亿比科新能源股份有限公司 | A kind of secondary pore forming method of lithium ion battery |
| CN112133887A (en) * | 2020-10-09 | 2020-12-25 | 昆山宝创新能源科技有限公司 | Quasi-solid-state battery pole piece and preparation method and application thereof |
| US20210249647A1 (en) * | 2018-05-17 | 2021-08-12 | Robert Bosch Gmbh | Method for producing porous electrodes for electrochemical cells |
| CN113293291A (en) * | 2021-05-21 | 2021-08-24 | 江苏中南锂业有限公司 | Preparation method of high-conductivity lithium extraction electrode |
| CN115084437A (en) * | 2022-08-23 | 2022-09-20 | 宁德时代新能源科技股份有限公司 | Negative pole piece and preparation method thereof, secondary battery and power utilization device |
| CN115832468A (en) * | 2022-11-17 | 2023-03-21 | 宁德时代新能源科技股份有限公司 | Lithium supplement electrode sheet, preparation method thereof, battery comprising lithium supplement electrode sheet and electric equipment |
| CN115911597A (en) * | 2021-09-24 | 2023-04-04 | 比亚迪股份有限公司 | Lithium ion battery electrode, preparation method thereof and lithium ion battery |
| CN115939307A (en) * | 2022-12-14 | 2023-04-07 | 东莞新能源科技有限公司 | Pole piece, secondary battery and contain its power consumption device |
-
2023
- 2023-04-11 CN CN202310381155.3A patent/CN116111042A/en active Pending
Patent Citations (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20100015327A1 (en) * | 2008-07-21 | 2010-01-21 | Battelle Memorial Institute | Methods and compositions for preparing porous electrodes |
| US20150357626A1 (en) * | 2014-06-05 | 2015-12-10 | 24M Technologies, Inc. | Porous semi-solid electrode and methods of manufacturing the same |
| US20190237731A1 (en) * | 2018-02-01 | 2019-08-01 | Samsung Electronics Co., Ltd. | Porous film, separator including porous film, electrochemical device including porous film, and method of preparing porous film |
| US20210249647A1 (en) * | 2018-05-17 | 2021-08-12 | Robert Bosch Gmbh | Method for producing porous electrodes for electrochemical cells |
| CN110224112A (en) * | 2018-11-07 | 2019-09-10 | 山东华亿比科新能源股份有限公司 | A kind of secondary pore forming method of lithium ion battery |
| CN112133887A (en) * | 2020-10-09 | 2020-12-25 | 昆山宝创新能源科技有限公司 | Quasi-solid-state battery pole piece and preparation method and application thereof |
| CN113293291A (en) * | 2021-05-21 | 2021-08-24 | 江苏中南锂业有限公司 | Preparation method of high-conductivity lithium extraction electrode |
| CN115911597A (en) * | 2021-09-24 | 2023-04-04 | 比亚迪股份有限公司 | Lithium ion battery electrode, preparation method thereof and lithium ion battery |
| CN115084437A (en) * | 2022-08-23 | 2022-09-20 | 宁德时代新能源科技股份有限公司 | Negative pole piece and preparation method thereof, secondary battery and power utilization device |
| CN115832468A (en) * | 2022-11-17 | 2023-03-21 | 宁德时代新能源科技股份有限公司 | Lithium supplement electrode sheet, preparation method thereof, battery comprising lithium supplement electrode sheet and electric equipment |
| CN115939307A (en) * | 2022-12-14 | 2023-04-07 | 东莞新能源科技有限公司 | Pole piece, secondary battery and contain its power consumption device |
Non-Patent Citations (1)
| Title |
|---|
| 庞爱民等: "中国电池工业20年", 中国轻工业出版社, pages: 124 - 167 * |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116646470A (en) * | 2023-07-18 | 2023-08-25 | 宁德时代新能源科技股份有限公司 | Positive electrode plate, preparation method of positive electrode plate, battery and electric equipment |
| CN117558921A (en) * | 2024-01-12 | 2024-02-13 | 宁德时代新能源科技股份有限公司 | Electrode manufacturing method, battery, and electricity using device |
| CN117558921B (en) * | 2024-01-12 | 2024-05-28 | 宁德时代新能源科技股份有限公司 | Electrode manufacturing method, battery, and electricity using device |
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