CN108493456A - Battery positive pole piece, lithium ion battery and reduction interface resistance method using it - Google Patents
Battery positive pole piece, lithium ion battery and reduction interface resistance method using it Download PDFInfo
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- CN108493456A CN108493456A CN201810391695.9A CN201810391695A CN108493456A CN 108493456 A CN108493456 A CN 108493456A CN 201810391695 A CN201810391695 A CN 201810391695A CN 108493456 A CN108493456 A CN 108493456A
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- Prior art keywords
- pole piece
- positive pole
- battery positive
- graphene
- graphene layer
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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
- H01M4/64—Carriers or collectors
- H01M4/66—Selection of materials
- H01M4/663—Selection of materials containing carbon or carbonaceous materials as conductive part, e.g. graphite, carbon fibres
-
- 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
- H01M4/64—Carriers or collectors
- H01M4/66—Selection of materials
- H01M4/665—Composites
- H01M4/667—Composites in the form of layers, e.g. coatings
-
- 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
Abstract
The present invention provide battery positive pole piece, using its lithium ion battery and reduce interface resistance method.The battery positive pole piece, including：Plus plate current-collecting body, the plus plate current-collecting body include graphene compound aluminium foil material layer；It is formed in the electrode active material on the plus plate current-collecting body surface, including electrode anode material, binder and conductive additive；Wherein, the graphene compound aluminium foil material layer includes：Aluminum foil substrate, parallel plane graphene layer positioned at the aluminum foil substrate surface and the vertical graphene layer being vertically positioned on the plane graphene layer；The mass percent that the content of the conductive additive accounts for the electrode active material content is 2%~12%.By by the current collector material for being used as anode pole piece with the graphene clad aluminum foil of vertical graphene layer is used, can effectively reduce the interface resistance of anode pole piece.
Description
Technical field
The present invention relates to battery material technologies, and in particular to battery positive pole piece, the lithium ion battery using it and reduction
The method of interface resistance.
Background technology
Lithium ion battery has that energy density is high, has extended cycle life and advantages of environment protection, has not only been widely used as hand
The power supply of the portable electronic devices such as machine, laptop, digital camera and video camera, and in pure electric automobile, mixing
The fields such as power electric automobile show good application prospect.Wherein electrode plates are the core composition portions of lithium ion battery
Point.Electrode plates are that electrode material is applied on collector to obtain.Common anode current collector of lithium ion battery is aluminium foil, is born
Pole collector is copper foil.However, since usually there is larger interface resistances between collector and electrode material, in electricity
Larger activation polarization is caused in the charge and discharge process of pond, seriously constrains the performance of lithium ion battery, especially multiplying power/work(
Rate performance.
Therefore, the interface resistance between collector and electrode material is effectively reduced, and then effectively improves lithium ion battery
Multiplying power/power-performance is this field urgent problem to be solved.
Invention content
The object of the present invention is to provide a kind of battery positive pole piece, using its lithium ion battery and reduce interface resistance
Method can by by the current collector material for being used as anode pole piece with the graphene clad aluminum foil of vertical graphene layer is used
Effectively to increase the contact area between collector and active material, to effectively reduce the interface resistance of anode pole piece.
To achieve the goals above, the present invention adopts the following technical scheme that：
The present invention provides a kind of battery positive pole piece, including：
Plus plate current-collecting body, the plus plate current-collecting body include graphene compound aluminium foil material layer；
It is formed in the electrode active material on the plus plate current-collecting body surface, including electrode anode material and conductive additive；
Wherein, the graphene compound aluminium foil material layer includes：It is aluminum foil substrate, parallel positioned at the aluminum foil substrate surface
Plane graphene layer and the vertical graphene layer being vertically positioned on the plane graphene layer；
The mass percent that the content of the conductive additive accounts for the electrode active material content is 2%~12%.
According to embodiment of the present invention, the thickness of the plane graphene layer is 5nm~30nm, the vertical stone
The thickness of black alkene layer is 10nm~1000nm.
According to embodiment of the present invention, the conductive additive be selected from conductive black, electrically conductive graphite, graphene,
It is one or more in carbon nanotube.
According to embodiment of the present invention, the positive electrode is selected from cobalt acid lithium, LiMn2O4, LiFePO4, metatitanic acid
It is one or more in lithium, cobalt nickel lithium manganate ternary material, nickel cobalt lithium aluminate ternary material.
The present invention provides a kind of lithium ion battery, including anode pole piece, diaphragm and cathode pole piece again, and the anode pole piece is
Above-mentioned battery positive pole piece.
The present invention also provides a kind of method reducing battery positive pole piece interface resistance, this method uses above-mentioned anode
Pole piece.
According to the description of above-mentioned technical proposal it is found that the beneficial effects of the present invention are：
The present invention can be shown by being used as plus plate current-collecting body by the graphene clad aluminum foil with vertical structure graphene layer
The contact area improved between the plus plate current-collecting body and active material is write, to effectively reduce between collector and electrode material
Interface resistance, and then reduce activation polarization of the electrode in charge and discharge process.
Description of the drawings
In order to which the embodiment of the present invention can be easier to understand, appended attached drawing is coordinated to elaborate below.
Fig. 1 is the material resistance of anode pole piece A and anode pole piece B prepared by embodiment 2 with conductive additive changes of contents
Curve graph；
Fig. 2 is the interface resistance of anode pole piece A and anode pole piece B prepared by embodiment 2 with conductive additive changes of contents
Curve graph；
Fig. 3 is the multiplying power test result of anode pole piece A and the button cell of anode pole piece B assemblings prepared by embodiment 2；
Fig. 4 is the electrochemical impedance spectroscopy of anode pole piece A and the button cell of anode pole piece B assemblings prepared by embodiment 2.
Specific implementation mode
The following contents provides many different embodiments or example.Certainly, these are only example, and not intended to limit sheet
Inventive embodiments.Experimental method used in embodiment is conventional method unless otherwise specified.Material used in embodiment
Material, reagent etc., are commercially available unless otherwise specified.The embodiment of the present invention can in each example repeated reference
Label and/or letter.This repeats to be for purposes of simplicity and clarity, itself to be not intended to specified discussed each implementation
Relationship between example and/or configuration.In addition, in the following description, descriptions of well-known structures and technologies are omitted, to avoid not
Necessarily obscure idea of the invention.
Furthermore in order to be easy the relationship of a component of the description embodiment of the present invention with another component or between layers,
Herein can with use space relative terms, for example, " relatively low ", " higher ", "horizontal", " vertical ", " in ... top ", " it
On ", " in ... lower section ", " ... it is beneath ", " upwards ", " downwards ", " top ", " bottom " and etc. derived from space correlation term (example
Such as " flatly ", " vertically ", " upward ", " down ").These space correlation terms are intended to cover include these components
Device different direction.
The present invention provides a kind of battery positive pole piece, including：
Plus plate current-collecting body, the plus plate current-collecting body include graphene compound aluminium foil material layer；
It is formed in the electrode active material on the plus plate current-collecting body surface, including electrode anode material and conductive additive；
Wherein, the graphene compound aluminium foil material layer includes：It is aluminum foil substrate, parallel positioned at the aluminum foil substrate surface
Plane graphene layer and the vertical graphene layer being vertically positioned on the plane graphene layer；
The mass percent that the content of the conductive additive accounts for the electrode active material content is 2%~12%.
The battery positive pole piece of the present invention significantly increases due to the use of the above-mentioned plus plate current-collecting body with vertical graphene layer
The strong contact area of itself and active material.In some embodiments, the thickness of the plane graphene layer is 5nm~30nm,
The thickness of the vertical graphene layer is 10nm~1000nm.
In some embodiments, conductive additive in conductive black, electrically conductive graphite, graphene, carbon nanotube one
Kind is a variety of.
In some embodiments, positive electrode is selected from cobalt acid lithium (LiCoO2), LiMn2O4 (LiMn2O4), LiFePO4
(LiFePO4), lithium titanate (Li4Ti5O12), cobalt nickel lithium manganate ternary material (LiNixCoyMnzO2), nickel cobalt lithium aluminate ternary material
(LiNixCoyAlzO2) in it is one or more.Wherein, LiNixCoyMnzO2Including but not limited to LiNi1/3Co1/3Mn1/3O2、
LiNi0.4Co0.4Mn0.2O2、LiNi0.5Co0.3Mn0.2O2、LiNi0.8Co0.1Mn0.1O2Deng；LiNixCoyAlzO2Including but not limited to
LiNi0.8Co0.15Al0.05O2。
The present invention also provides a kind of lithium ion battery, including anode pole piece, diaphragm, electrolyte and cathode pole piece, it is described just
Pole pole piece is above-mentioned battery positive pole piece.The interface resistance of the battery positive pole piece is relatively low, to ensure that lithium ion battery
It is functional.
The present invention provides a kind of method reducing battery positive pole piece interface resistance again, uses above-mentioned battery positive pole piece.
It is illustrated below by specific embodiment.
The preparation of 1 graphene clad aluminum foil of embodiment
Commercial aluminum foil current collector is put into (Shenzhen section is brilliant) in plasma chemical vapor deposition device, is passed through argon gas repeatedly
Cleaning 3~5 times, which is heated to 590 DEG C with the heating rate of 20 DEG C/min, then passes to methane (flow 10sccm), adjusts
Section plasma apparatus makes it generate uniform aura covering aluminium foil, is reacted, and the reaction time is 20 minutes.After reaction,
Wait for that equipment is down to room temperature to get to the graphene clad aluminum foil with vertical graphene layer.
The preparation of 2 anode pole piece of embodiment
By LiFePO4 (LiFePO4), conductive additive (conductive black), binder polyvinylidene fluoride (PVDF) etc. with
Organic solvent N-Methyl pyrrolidone (NMP) is uniformly mixed and is made into slurry, wherein LiFePO4, conductive black and PVDF quality
Than being 90：5：5.By the LiFePO of configuration4Slurry is respectively coated multiple with the graphene with vertical graphene layer in normal aluminium foil
It closes on aluminium foil, in 60 DEG C of baking ovens after dry 6h, 80 DEG C of vacuum drying 8h respectively obtain common LiFePO4Anode pole piece A and sheet
The LiFePO of invention4Anode pole piece B.
Test case 1
With four probe surface resistance measuring instruments, the surface resistance of anode pole piece A and anode pole piece B are measured respectively, wherein positive pole
The surface resistance of piece A is (8.48 ± 3.23) × 101Ω/cm2, the surface resistance of anode pole piece B is (1.88 ± 0.18) × 10-3Ω/
cm2.As it can be seen that the anode pole piece B of the present invention is used as anode as a result of the graphene clad aluminum foil with vertical graphene layer
Collector greatly reduces the surface resistance of anode pole piece.
Test case 2
In order to further study influence of the other factors to anode pole piece resistance, using electrode resistance measuring instrument, (Hioki gives birth to
Production) respectively measure anode pole piece A and anode pole piece B material resistance and interface resistance.
Fig. 1 is the material resistance of anode pole piece A and anode pole piece B prepared by embodiment 2 with conductive additive changes of contents
Curve graph.As shown in Figure 1, when the content of conductive additive is identical, the material resistance of anode pole piece A and anode pole piece B
Difference very little, almost unanimously, it is seen that plus plate current-collecting body influences the material resistance of anode pole piece little.
Fig. 2 is the interface resistance of anode pole piece A and anode pole piece B prepared by embodiment 2 with conductive additive changes of contents
Curve graph.As shown in Fig. 2, the interface resistance of anode pole piece A is apparently higher than the interface resistance of anode pole piece B, and anode pole piece A
Interface resistance hardly influenced by the dosage of conductive additive.And as seen in Figure 2, anode pole piece B's of the invention
Interface resistance is not only under equal conditions below anode pole piece A, and with the increase of conductive additive content, interface resistance is also
It can further significantly reduce.The mass percent that conductive additive accounts for electrode active material is preferably 2%~12%, further excellent
It is selected as 5%~12%.The result shows that can effectively reduce electrode pole using with the plus plate current-collecting body with vertical graphene layer
The interface resistance of piece.
Test case 3
Chemical property shadow when further anode pole piece of the test with different interface resistances is applied to lithium ion battery
It rings.
Anode pole piece A and anode pole piece B (its diameter is 1cm) are taken, is assembled into 2016 type buttons with metal lithium sheet respectively
Half-cell, electrolyte are the LiPF of 50 microlitres of 1mol/L6Electrolyte (volume ratio EC：DMC=50：50).Positive pole is tested respectively
Piece A and chemical properties of the anode pole piece B on the lithium ion battery.
Fig. 3 is the multiplying power test result of anode pole piece A and the button cell of anode pole piece B assemblings prepared by embodiment 2.Its
In, 1C=171mA/g.From figure 3, it can be seen that anode pole piece B has better high rate performance than anode pole piece A.Fig. 4 is to implement
The electrochemical impedance spectroscopy of anode pole piece A prepared by example 2 and the button cell of anode pole piece B assemblings, from fig. 4, it can be seen that with just
Pole pole piece A is compared, and anode pole piece B is on the graphene clad aluminum foil collector with vertical graphene layer with smaller charge
Shift internal resistance.
The present invention is disclosed as above with several embodiments, understands the present invention with sharp those of ordinary skill in the art.This field
Based on the present invention can be used in those of ordinary skill, other techniques and structure are designed or adjust, to implement the identical of embodiment
Purpose, and/or reach the same advantage of embodiment.Those of ordinary skill in the art should be understood that above-mentioned equivalent replacement without deviating from this
The design of invention and scope, and can without departing from the present invention design under the scope of carry out these different changes, displacement, and tune
It is whole.
Claims (6)
1. a kind of battery positive pole piece, which is characterized in that including：
Plus plate current-collecting body, the plus plate current-collecting body include graphene compound aluminium foil material layer；
It is formed in the electrode active material on the plus plate current-collecting body surface, including electrode anode material, binder and conductive addition
Agent；
Wherein, the graphene compound aluminium foil material layer includes：Aluminum foil substrate, the parallel plane positioned at the aluminum foil substrate surface
Graphene layer and the vertical graphene layer being vertically positioned on the plane graphene layer；
The mass percent that the content of the conductive additive accounts for the electrode active material content is 2%~12%.
2. battery positive pole piece according to claim 1, which is characterized in that the thickness of the plane graphene layer is 5nm
The thickness of~30nm, the vertical graphene layer are 10nm~1000nm.
3. battery positive pole piece according to claim 1, which is characterized in that the conductive additive be selected from conductive black,
It is one or more in electrically conductive graphite, graphene, carbon nanotube.
4. battery positive pole piece according to claim 1, which is characterized in that the positive electrode is selected from cobalt acid lithium, mangaic acid
It is one or more in lithium, LiFePO4, lithium titanate, cobalt nickel lithium manganate ternary material, nickel cobalt lithium aluminate ternary material.
5. a kind of lithium ion battery, which is characterized in that including anode pole piece, diaphragm, electrolyte and cathode pole piece, the anode pole
Piece is claim 1-4 any one of them battery positive pole pieces.
6. a kind of method reducing battery positive pole piece interface resistance, which is characterized in that using described in claim any one of 1-4
Battery positive pole piece.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
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| CN201810391695.9A CN108493456B (en) | 2018-04-27 | 2018-04-27 | Battery anode piece, lithium ion battery applying same and method for reducing interface resistance |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810391695.9A CN108493456B (en) | 2018-04-27 | 2018-04-27 | Battery anode piece, lithium ion battery applying same and method for reducing interface resistance |
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| CN108493456A true CN108493456A (en) | 2018-09-04 |
| CN108493456B CN108493456B (en) | 2021-03-12 |
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Cited By (1)
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| CN114824262A (en) * | 2021-01-29 | 2022-07-29 | 优材科技有限公司 | Conductive structure and battery |
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