CN111129425A - Lithium ion battery thick pole piece and preparation method thereof - Google Patents

Lithium ion battery thick pole piece and preparation method thereof Download PDF

Info

Publication number
CN111129425A
CN111129425A CN201911365051.3A CN201911365051A CN111129425A CN 111129425 A CN111129425 A CN 111129425A CN 201911365051 A CN201911365051 A CN 201911365051A CN 111129425 A CN111129425 A CN 111129425A
Authority
CN
China
Prior art keywords
electrode material
pole piece
ion battery
lithium ion
current collector
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CN201911365051.3A
Other languages
Chinese (zh)
Inventor
黄明
张章明
赵会江
龚金保
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Hengdian Group DMEGC Magnetics Co Ltd
Original Assignee
Hengdian Group DMEGC Magnetics Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Hengdian Group DMEGC Magnetics Co Ltd filed Critical Hengdian Group DMEGC Magnetics Co Ltd
Priority to CN201911365051.3A priority Critical patent/CN111129425A/en
Publication of CN111129425A publication Critical patent/CN111129425A/en
Pending legal-status Critical Current

Links

Images

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/13—Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/05—Accumulators with non-aqueous electrolyte
    • H01M10/052—Li-accumulators
    • 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
    • H01M4/04—Processes of manufacture in general
    • H01M4/0402—Methods of deposition of the material
    • H01M4/0404—Methods of deposition of the material by coating on electrode collectors
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/13—Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
    • H01M4/139—Processes of manufacture
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • 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
    • 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
    • H01M4/621—Binders
    • 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
    • H01M4/624—Electric conductive fillers
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/10—Energy storage using batteries

Landscapes

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

Abstract

The invention relates to a lithium ion battery thick pole piece and a preparation method thereof, wherein the lithium ion battery thick pole piece comprises a current collector and an electrode material layer, wherein the surface of the current collector is provided with a bulge, and the electrode material layer covers an area of the current collector surface provided with the bulge, so that the electronic conductivity of the lithium ion battery thick pole piece can be obviously improved, and the contact resistance of the lithium ion battery thick pole piece is further reduced; meanwhile, the solid electrolyte and polyethylene oxide are added into the electrode material slurry in a certain proportion, so that the ionic conductivity of the pole piece is improved, and the multiplying power performance of a half-cell assembled by the thick pole piece of the lithium ion battery is also obviously improved.

Description

Lithium ion battery thick pole piece and preparation method thereof
Technical Field
The invention belongs to the field of lithium ion batteries, and relates to a thick pole piece of a lithium ion battery and a preparation method thereof.
Background
The lithium ion battery has high energy density, large output power, environmental protection, no toxic substances such as lead, cadmium, mercury and the like, and has wide application prospect in the aspects of new energy automobiles and energy storage. From the design point of view, improving electrode sheet thickness can increase the active material content that the mass flow body of unit area can bear to promote the energy density of electric core. However, in the practical application process, the increase of the thickness of the electrode piece leads to the rapid reduction of the rate capability of the battery, so that the application of the thick electrode piece of the lithium ion battery is restricted.
CN101002351A discloses a method for forming a solid sulfur electrode by depositing one or more layers of slurry on a current collector, wherein the content, composition, drying condition and rolling condition of each layer of slurry are controlled to form an effect of increasing the porosity gradient from the current collector to the surface layer, and the effect of wetting the electrode with electrolyte is improved, thereby achieving the purpose of improving the ionic conductivity of the electrode. The problem that the overall electrical performance of the electrode pole piece is reduced due to the reduction of the electronic conductivity caused by the increase of the thickness is not considered in the scheme, and along with the increase of the thickness of the lithium ion battery pole piece, the electronic conductivity of the lithium ion battery pole piece is reduced, so that the multiplying power performance of the lithium ion battery assembled by the lithium ion battery pole piece is reduced.
CN102324493A discloses a thick electrode with good electrochemical performance, wherein by arranging two layers of electrode membranes, the inner layer of electrode membrane has high electrical conductivity and small porosity (relative to the outer layer); the conductivity of the outer electrode membrane is reduced, the porosity is increased, the purpose of balancing the difference between the electronic conductance and the ionic conductance of the inner electrode membrane and the outer electrode membrane is achieved through controlling the conductivity and the porosity, but the reduction of the conductivity of the outer layer can aggravate the attenuation of the electronic conductance performance of the electrode membrane, and the influence on the attenuation of the performance of the outer electrode membrane is large.
Therefore, the development of the thick pole piece of the lithium ion battery and the preparation method thereof, which have the advantage that the electronic conductivity and the ionic conductivity of the pole piece are reduced less along with the increase of the thickness of the pole piece, are still of great significance.
Disclosure of Invention
The invention aims to provide a lithium ion battery thick pole piece and a preparation method thereof, wherein the lithium ion battery thick pole piece comprises a current collector and an electrode material layer, wherein the surface of the current collector is provided with a bulge, and the electrode material layer covers an area of the current collector with the bulge, so that the electronic conductivity of the lithium ion battery thick pole piece can be obviously improved, and the contact resistance of the lithium ion battery thick pole piece is further reduced; meanwhile, a certain proportion of solid electrolyte and polyethylene oxide are added into the electrode material slurry, so that the ionic conductivity of the pole piece is improved; the rate capability of the half-cell assembled by the thick pole piece of the lithium ion battery is also obviously improved.
In order to achieve the purpose, the invention adopts the following technical scheme:
in a first aspect, the invention provides a lithium ion battery thick pole piece, which comprises a current collector and an electrode material layer, wherein a protrusion is arranged on the surface of the current collector, and the electrode material layer covers an area where the protrusion is arranged on the surface of the current collector.
The surface of the current collector is provided with the protrusions, and the electrode material layer covers the area with the protrusions on the surface of the current collector, so that the electronic conductivity of the pole piece of the lithium ion battery is improved, the problem of reduction of the electronic conductivity of the pole piece caused by increase of the thickness of the electrode material layer is solved, and the rate capability of the lithium ion battery is improved.
The thickness of the lithium ion battery thick pole piece refers to the thickness of an electrode material layer in the lithium ion battery pole piece being more than or equal to 200 mu m.
Preferably, the protrusion is a conical protrusion.
The conical bulge arranged on the surface of the current collector and the plane of the current collector are of an integral structure.
Preferably, the axis of the conical projection is perpendicular to the plane of the current collector.
Preferably, the height of the pyramidal protrusions is 50-80%, such as 55%, 60%, 65%, 70% or 75% of the thickness of the electrode material layer.
The conical protrusions on the current collector are covered by the electrode material layer, the height of the conical protrusions is limited to be 50-80% of the thickness of the electrode material layer, and the conical protrusions are beneficial to improving the electronic conductivity of a pole piece to the maximum extent, so that the rate capability of a lithium ion battery is optimized; when the height of the conical projection is less than 50% of the thickness of the electrode material layer, the electronic conductivity of the pole piece is obviously reduced; when the height of the pyramidal projections is more than 80% of the thickness of the electrode material layer, the probability that the pyramidal projections directly contact the separator or the negative electrode is greatly increased with the loss of the active material during the cycle.
The height of the conical projection here refers to the distance of the apex of the conical projection from the plane in which the base of the conical projection lies.
Preferably, the compacted density of the electrode material layer is 1.0-4.0g/cm3E.g. 1.5g/cm3、2g/cm3、2.5g/cm3、3g/cm3Or 3.5g/cm3And the like.
Preferably, the material of the current collector is aluminum.
The current collector is aluminum corresponding to the positive active material, and the current collector is copper corresponding to the negative active material.
Preferably, the thickness of the current collector is 10-2000 μm, such as 20 μm, 50 μm, 100 μm, 200 μm, 500 μm, 1000 μm, 1500 μm or 1900 μm, etc.
Preferably, the thickness of the electrode material layer is 200-2000 μm, such as 300 μm, 500 μm, 800 μm, 1000 μm, 1300 μm, 1500 μm or 1800 μm.
Preferably, the taper of the conical projection is in the range of 0.01-0.38, such as 0.02, 0.05, 0.1, 0.15, 0.2, 0.25, 0.3, or 0.35, etc.
Preferably, the gap between adjacent pyramidal protrusions is 10-500 μm, such as 20 μm, 50 μm, 100 μm, 200 μm, 300 μm, or 400 μm, etc.
The gap between adjacent pyramidal projections herein refers to the closest distance between the bottom surfaces of adjacent pyramidal projections.
Preferably, the gap between any adjacent conical projections is the same.
Preferably, still be equipped with utmost point ear welding position on the mass flow body, it does not set up arch and electrode material layer on the utmost point ear welding position.
Preferably, the composition of the electrode material layer includes an active material, a binder, a conductive agent, polyethylene oxide (PEO), and a solid electrolyte.
According to the electrode material layer disclosed by the invention, polyethylene oxide and solid electrolyte are added into the traditional electrode material, so that the ionic conductivity of the lithium ion battery pole piece is favorably improved, and the rate capability of the lithium ion battery is further improved.
Preferably, the binder comprises polyvinylidene fluoride (PVDF).
Preferably, the conductive agent includes conductive carbon black SP, Carbon Nanotubes (CNT), conductive carbon fibers VGCF, or graphene.
Preferably, the solid electrolyte comprises lithium lanthanum zirconium oxygen and/or lithium lanthanum titanate.
Preferably, the active material is a positive electrode material.
Preferably, the electrode material layer comprises the following components in percentage by mass based on 100% of the mass of the electrode material layer:
Figure BDA0002338179870000041
the electrode material layer comprises the following components: the mass percentage of the active material in the electrode material layer is 70-99%, for example 73%, 75%, 78%, 80%, 83%, 85%, 88%, 90%, 93%, 95% or 98%, etc., the mass percentage of the binder is 0.01-10%, for example 0.05%, 0.1%, 0.5%, 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8% or 9%, etc., the mass percentage of the conductive agent is 0.01-10%, for example 0.05%, 0.1%, 0.5%, 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8% or 9%, etc., the mass percentage of the polyethylene oxide is 0.1-5%, for example 0.5%, 1%, 1.5%, 2%, 3% or 4%, etc., the mass percentage of the solid electrolyte is 0.1-10%, for example 0.5%, 1%, 1.5%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, or 9%, etc.
Preferably, the mass percentage of the conductive agent in the electrode material layer is 1.0-6.0%, such as 2%, 3%, 4%, or 5%.
Preferably, the mass percentage of the binder in the electrode material layer is 1.0-8.0%, such as 2%, 3%, 4%, 5%, 6%, 7%, or the like.
The invention improves the mass percentage content of the conductive agent and the binding agent in the electrode material layer, thereby being beneficial to improving the electronic conductivity of the lithium ion battery pole piece and optimizing the rate capability of the lithium ion battery.
Preferably, the current collector is aluminum; the active material is a positive electrode material.
Preferably, the positive electrode material includes any one of lithium cobaltate, lithium manganate, lithium iron phosphate, ternary nickel cobalt manganese material (NCM), Nickel Cobalt Aluminum (NCA), or lithium titanate, or a combination of at least two of them, and the combination exemplarily includes a combination of lithium cobaltate and lithium manganate, a combination of lithium iron phosphate and ternary nickel cobalt manganese material, or a combination of nickel cobalt aluminum and lithium titanate, or the like.
In a second aspect, the present invention provides a method for preparing a thick pole piece of a lithium ion battery according to the first aspect, wherein the method comprises the following steps:
(a) preparing electrode material slurry; the electrode material slurry contains an active material, a binder, a conductive agent, a solvent, polyethylene oxide and a solid electrolyte;
(b) and (c) loading the electrode material slurry obtained in the step (a) on a current collector, drying and then stamping to obtain the lithium ion battery thick pole piece.
Preferably, the method for preparing an electrode material slurry according to step (a) includes mixing an active material, a binder, a conductive agent, and a solvent to obtain a mixed slurry, and then adding polyethylene oxide and a solid electrolyte to mix to obtain an electrode material slurry.
Preferably, the step (b) of loading the electrode material slurry of step (a) on the current collector is to place the current collector in a mold, and then adding the electrode material slurry and drying.
The method for loading the electrode material slurry on the current collector in the preparation process of the lithium ion battery thick pole piece comprises the steps of adopting a mold matched with the current collector for use, wherein the height of the mold corresponds to the sum of the thicknesses of the current collector and an electrode material layer, the size of the cross section of the mold corresponds to the size of the current collector, firstly placing the current collector in the mold in the preparation process, then filling the electrode material slurry into the mold until the upper surface of the slurry is flush with the upper end plane of the mold, then drying, and carrying out post-treatment to obtain the lithium ion battery thick pole piece.
Preferably, the drying is vacuum drying.
Preferably, the temperature of the vacuum drying is 60-100 ℃, such as 70 ℃, 80 ℃ or 90 ℃ and the like.
Preferably, the vacuum drying time is 2-12h, such as 3h, 5h, 7h, 9h or 11 h.
The stamping operation aims to enable the prepared thick pole piece of the lithium ion battery to reach a specific compaction density.
As a preferred technical scheme, the preparation method of the lithium ion battery thick pole piece comprises the following steps:
(1) mixing an active substance, a binder and a conductive agent according to a mass ratio to obtain mixed slurry;
(2) adding polyethylene oxide and solid electrolyte into the mixed slurry obtained in the step (1) according to the mass ratio, and mixing to obtain electrode material slurry;
(3) and (3) placing a current collector in a mould, then adding the electrode material slurry, drying in vacuum at 60-100 ℃ for 2-12h, and stamping to obtain the thick pole piece of the lithium ion battery.
The current collector with a specific structure is adopted in the thick pole piece of the lithium ion battery, the influence of the increase of the thickness of the pole piece on the electronic conductivity of the pole piece can be obviously relieved, and meanwhile, a certain proportion of solid electrolyte and PEO are added into the electrode material layer to relieve the influence of the increase of the thickness of the pole piece on the ionic conductivity of the pole piece, so that the multiplying power performance of the lithium ion button battery assembled by the thick pole piece of the lithium ion battery is optimized.
Compared with the prior art, the invention has the following beneficial effects:
(1) the thick pole piece of the lithium ion battery adopts the current collector with the surface provided with the protrusions, and the surface of the current collector is covered with the battery material layer, so that the problem of the reduction of the electronic conductivity of the pole piece caused by the increase of the thickness of the pole piece can be obviously solved, and the contact resistance of the thick pole piece of the lithium ion battery can reach below 150 omega.
(2) The thick pole piece of the lithium ion battery is used for the lithium ion button battery, and the multiplying power performance of the obtained lithium ion battery is obviously improved.
Drawings
Fig. 1 is a schematic structural view of a current collector according to the invention;
fig. 2 is a schematic structural diagram of a thick pole piece of the lithium ion battery of the present invention.
1-current collector, 2-conical bulge, 3-tab welding position and 4-electrode material layer.
Detailed Description
The technical solution of the present invention is further explained by the following embodiments. It should be understood by those skilled in the art that the examples are only for the understanding of the present invention and should not be construed as the specific limitations of the present invention.
The structural schematic diagram of the current collector is shown in fig. 1, and as can be seen from fig. 1, conical protrusions 2 are arranged on the surface of the current collector 1, and the conical protrusions 2 are distributed at equal intervals; and the current collector 1 is also provided with a tab welding position 3.
The structural schematic diagram of the lithium ion battery thick pole piece is shown in fig. 2, and as can be seen from fig. 2, the lithium ion battery thick pole piece comprises a current collector 1 and an electrode material layer 4 covering the current collector 1, a conical protrusion on the surface of the current collector 1 is covered by the electrode material layer 4, a tab welding position 3 is further arranged on the current collector 1, and the tab welding position 3 is not covered by the electrode material layer and the conical protrusion.
Example 1
Preparing a pole piece by using a lithium iron phosphate positive electrode material;
this embodiment the mass flow body of the thick pole piece of lithium ion battery's material is aluminium, and the thickness of mass flow body is 40 μm, the mass flow body surface is provided with the toper arch, the bellied height of toper is 300 μm, and the tapering is 0.1, and the clearance between the adjacent toper arch is 100 μm.
With the mass of the obtained electrode material layer as 100%, the electrode material slurry adopted in this embodiment includes the following components by mass:
Figure BDA0002338179870000081
the preparation method of the lithium ion battery thick pole piece comprises the following steps:
(1) preparing electrode material slurry;
(a) preparing conventional lithium iron phosphate slurry: mixing lithium iron phosphate, a conductive agent, a binder and deionized water according to a formula ratio to prepare a water-based lithium iron phosphate slurry; the conductive agent is SP, the binder is PVDF, and the mass ratio of the lithium iron phosphate to the conductive agent to the binder is 90:4: 6; the solid content of the aqueous lithium iron phosphate slurry is 51 percent;
(b) then adding PEO and a Lanthanum Lithium Titanate (LLTO) solid electrolyte according to the formula ratio, and uniformly dispersing to obtain the electrode material slurry;
(2) placing a current collector in a mould, then adding the electrode material slurry obtained in the step (1), paving the slurry on the current collector until the upper surface of the slurry is flush with the edge of the upper end of the mould, wherein the height of the mould is 1mm, namely the sum of the thicknesses of the current collector and the electrode material slurry layer is 1 mm; and then placing the lithium ion battery anode plate in a vacuum oven at 80 ℃ for baking for 4h, cooling to room temperature, and stamping until the thickness of the anode plate is 0.5mm to obtain the lithium ion battery anode plate.
Example 2
Preparing a pole piece by using a ternary 523 type positive pole material;
the mass flow body of lithium ion battery thick pole piece is aluminium, and the thickness of mass flow body is 50 mu m, the mass flow body surface is provided with the toper arch, the bellied height of toper is 500 mu m, and the tapering is 0.1, and the clearance between the adjacent toper arch is 150 mu m.
With the mass of the obtained electrode material layer as 100%, the electrode material slurry adopted in this embodiment includes the following components by mass:
Figure BDA0002338179870000091
the preparation method of the lithium ion battery thick pole piece comprises the following steps:
(1) preparing electrode material slurry;
(a) preparing conventional lithium nickel cobalt manganese oxide slurry: mixing the nickel cobalt lithium manganate, a conductive agent, a binder and N-methyl pyrrolidone (NMP) according to a formula ratio to prepare nickel cobalt lithium manganate slurry; the conductive agent is CNT, the binder is PVDF, and the mass ratio of the nickel cobalt lithium manganate to the conductive agent to the binder is 92:5: 3; the solid content of the nickel cobalt lithium manganate slurry is 70%;
(b) then adding PEO and a lanthanum lithium titanate solid electrolyte according to the formula ratio, and uniformly dispersing to obtain the electrode material slurry;
(2) placing a current collector in a mould, then adding the electrode material slurry in the step (1) in an environment with the water content and the oxygen content controlled below 0.1ppm, paving the slurry on the current collector until the upper surface of the slurry is flush with the upper end edge of the mould, wherein the height of the mould is 1.5mm, namely the sum of the thicknesses of the current collector and the electrode material slurry layer is 1.5 mm; and then placing the lithium ion battery anode plate in a vacuum oven at 60 ℃ for baking for 6h, cooling to room temperature, and stamping until the thickness of the anode plate is 0.8mm to obtain the lithium ion battery anode plate.
Example 3
The difference between this example and example 1 is that the height of the conical projection on the current collector is 240 μm, and the other conditions are exactly the same as those in example 1.
Example 4
The difference between this example and example 1 is that the height of the conical projection on the current collector is 400 μm, and other conditions are exactly the same as those in the example.
Example 5
The difference between this embodiment and embodiment 1 is that the taper of the tapered protrusion is 0.35, and the other conditions are the same as those in the embodiment.
Example 6
The difference between this example and example 1 is that the taper of the tapered protrusion is 0.05, and the other conditions are the same as those in the example.
Comparative example 1
The comparative example is different from example 1 only in that the surface of the current collector used does not include the tapered protrusions, that is, the surface thereof is of a planar structure, and other conditions are exactly the same as those in example 1.
Comparative example 2
The comparative example is different from example 2 only in that the surface of the current collector used does not include the tapered protrusions, that is, the surface thereof is of a planar structure, and other conditions are exactly the same as those in example 2.
Comparative example 3
The comparative example is different from example 1 in that polyethylene oxide and a solid electrolyte are not added in the preparation of the electrode material slurry, and other conditions are exactly the same as those of example 1.
And (3) performance testing:
testing the contact resistance of the lithium ion battery pole pieces prepared in the examples 1-6 and the comparative examples 1-3, wherein the testing method is to use two probe pole piece resistances to test the contact resistance of the pole pieces; the test results are shown in table 1;
TABLE 1
Contact resistance (omega)
Example 1 143.24
Example 2 126.45
Example 3 147.82
Example 4 136.17
Example 5 144.75
Example 6 142.64
Comparative example 1 209.88
Comparative example 2 197.76
Comparative example 3 206.73
The current collector with the conical bulges arranged on the surface is adopted in the thick pole piece of the lithium ion battery, so that the reduction of the electronic conductivity of the pole piece caused by the increase of the thickness of the pole piece can be obviously slowed down, and the contact resistance of the pole piece is reduced.
And (3) capacity testing: a circular pole piece with the diameter of 13mm is punched out of the lithium ion battery pole piece prepared in the embodiment 1-2 and the comparative example 1-3, a 2032 button half cell is prepared, the rate capability of the button half cell is tested, and the test results are shown in the table 2, wherein the discharge capacity of 0.1C, the rate capability of 0.2C/0.1C and the rate capability of 0.5/0.1C are respectively shown in the table;
TABLE 2
0.1C(mAh/g) 0.2C/0.1C 0.5C/0.1C
Example 1 143 78.5％ 59.7％
Example 2 162 85.1％ 72.7％
Comparative example 1 132 73.2％ 49.7％
Comparative example 2 156 76.8％ 58.1％
Comparative example 3 128 69.5％ 46.7％
As can be seen from the above table, the rate capability of the half-cell prepared by the thick lithium ion battery pole piece is obviously improved.
The applicant declares that the above description is only a specific embodiment of the present invention, but the scope of the present invention is not limited thereto, and it should be understood by those skilled in the art that any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present invention are within the scope and disclosure of the present invention.

Claims (10)

1. The thick pole piece of the lithium ion battery is characterized by comprising a current collector and an electrode material layer, wherein the surface of the current collector is provided with a protrusion, and the electrode material layer covers the surface of the current collector and is provided with a protruding area.
2. The thick lithium ion battery pole piece of claim 1, wherein the protrusions are tapered protrusions;
preferably, the height of the conical projection is 50-80% of the thickness of the electrode material layer;
preferably, the material of the current collector is aluminum;
preferably, the thickness of the current collector is 10 to 2000 μm.
3. The thick lithium ion battery plate of claim 1 or 2, wherein the thickness of the electrode material layer is 200-2000 μm.
4. The thick lithium ion battery pole piece of claim 2 or 3, wherein the taper range of the tapered protrusion is 0.01-0.38;
preferably, the gap between adjacent pyramidal protrusions is 10-500 μm.
5. The thick pole piece of lithium ion battery of any one of claims 1-4, wherein said current collector is further provided with a tab welding position, and said tab welding position is not provided with a protrusion and an electrode material layer.
6. The thick pole piece of lithium ion battery of any one of claims 1-5, wherein the composition of the electrode material layer comprises active substance, binder, conductive agent, polyethylene oxide and solid electrolyte;
preferably, the active material is a positive electrode material;
preferably, the electrode material layer comprises the following components in percentage by mass based on 100% of the mass of the electrode material layer:
Figure FDA0002338179860000011
Figure FDA0002338179860000021
7. the thick pole piece of lithium ion battery of claim 6, wherein the positive electrode material comprises any one of lithium cobaltate, lithium manganate, lithium iron phosphate, nickel cobalt manganese ternary material, nickel cobalt aluminum or lithium titanate or a combination of at least two of them.
8. The method for preparing the thick pole piece of the lithium ion battery according to any one of claims 1 to 7, wherein the method comprises the following steps:
(a) preparing electrode material slurry; the electrode material slurry contains an active material, a binder, a conductive agent, a solvent, polyethylene oxide and a solid electrolyte;
(b) loading the electrode material slurry obtained in the step (a) on a current collector, drying and then stamping to obtain the thick pole piece of the lithium ion battery;
preferably, the method for preparing an electrode material slurry according to step (a) includes mixing an active material, a binder, a conductive agent, and a solvent to obtain a mixed slurry, and then adding polyethylene oxide and a solid electrolyte to mix to obtain an electrode material slurry.
9. The method of claim 8, wherein the step (b) of loading the electrode material slurry of step (a) on the current collector comprises placing the current collector in a mold, adding the electrode material slurry, and drying;
preferably, the drying is vacuum drying;
preferably, the temperature of the vacuum drying is 60-100 ℃;
preferably, the vacuum drying time is 2-12 h.
10. A method according to claim 8 or 9, characterized in that the method comprises the steps of:
(1) mixing an active substance, a binder and a conductive agent according to a mass ratio to obtain mixed slurry;
(2) adding polyethylene oxide and solid electrolyte into the mixed slurry obtained in the step (1) according to the mass ratio, and mixing to obtain electrode material slurry;
(3) and placing a current collector in a mould, then adding the electrode material slurry, drying in vacuum at 60-100 ℃ for 2-12h, and stamping to a specified thickness to obtain the thick pole piece of the lithium ion battery.
CN201911365051.3A 2019-12-26 2019-12-26 Lithium ion battery thick pole piece and preparation method thereof Pending CN111129425A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201911365051.3A CN111129425A (en) 2019-12-26 2019-12-26 Lithium ion battery thick pole piece and preparation method thereof

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201911365051.3A CN111129425A (en) 2019-12-26 2019-12-26 Lithium ion battery thick pole piece and preparation method thereof

Publications (1)

Publication Number Publication Date
CN111129425A true CN111129425A (en) 2020-05-08

Family

ID=70502909

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201911365051.3A Pending CN111129425A (en) 2019-12-26 2019-12-26 Lithium ion battery thick pole piece and preparation method thereof

Country Status (1)

Country Link
CN (1) CN111129425A (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112952042A (en) * 2021-03-08 2021-06-11 上海兰钧新能源科技有限公司 Preparation method of paste-mixing brick for lithium ion battery pole piece
CN113517421A (en) * 2021-07-12 2021-10-19 四川无量智慧道桥科技有限公司 Lithium battery pole piece die forming and die casting system and die casting process
CN114843438A (en) * 2022-06-16 2022-08-02 惠州锂威电子科技有限公司 Battery pole piece, preparation method thereof and lithium ion battery

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN205723772U (en) * 2016-05-05 2016-11-23 东莞市迪高电池科技有限公司 Alkaline battery collector and alkaline battery
CN107482223A (en) * 2017-09-29 2017-12-15 清华大学 The preparation method of lithium ion battery electrode material composition, lithium ion battery and its electrode slurry
CN207490013U (en) * 2017-09-29 2018-06-12 程杰 A kind of activated carbon electrodes
CN109643782A (en) * 2016-08-30 2019-04-16 罗伯特·博世有限公司 Electrode material for Li-ion batteries piles

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN205723772U (en) * 2016-05-05 2016-11-23 东莞市迪高电池科技有限公司 Alkaline battery collector and alkaline battery
CN109643782A (en) * 2016-08-30 2019-04-16 罗伯特·博世有限公司 Electrode material for Li-ion batteries piles
CN107482223A (en) * 2017-09-29 2017-12-15 清华大学 The preparation method of lithium ion battery electrode material composition, lithium ion battery and its electrode slurry
CN207490013U (en) * 2017-09-29 2018-06-12 程杰 A kind of activated carbon electrodes

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
XINSHENG WU等: "High-Performance, Low-Cost, and Dense-Structure Electrodes with High Mass Loading for Lithium-Ion Batteries", 《ADV. FUNCT. MATER.》 *

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112952042A (en) * 2021-03-08 2021-06-11 上海兰钧新能源科技有限公司 Preparation method of paste-mixing brick for lithium ion battery pole piece
CN113517421A (en) * 2021-07-12 2021-10-19 四川无量智慧道桥科技有限公司 Lithium battery pole piece die forming and die casting system and die casting process
CN113517421B (en) * 2021-07-12 2022-06-21 四川无量智慧道桥科技有限公司 Lithium battery pole piece die forming and die casting system and die casting process
CN114843438A (en) * 2022-06-16 2022-08-02 惠州锂威电子科技有限公司 Battery pole piece, preparation method thereof and lithium ion battery

Similar Documents

Publication Publication Date Title
CN111584825B (en) Negative plate and preparation method and application thereof
WO2011079482A1 (en) Battery
CN103199217A (en) Lithium-rich pole piece of lithium ion battery and preparation method thereof
CN111129425A (en) Lithium ion battery thick pole piece and preparation method thereof
CN202189864U (en) Positive electrode piece of high-capacity lithium iron phosphate type lithium ion cell
JP2023519287A (en) Lithium iron phosphate positive electrode sheet and manufacturing method thereof, lithium iron phosphate lithium ion battery
CN109860603B (en) Lithium battery pole piece, preparation method thereof and lithium battery
CN110620211A (en) High-energy-density lithium ion battery and preparation method thereof
CN212625654U (en) Pole piece and lithium ion battery
CN110600680A (en) Positive electrode slurry, positive plate comprising positive electrode slurry and lithium ion battery
CN108878893B (en) Modified current collector for negative electrode of quick-charging lithium ion battery and preparation method thereof
CN212907803U (en) Lithium ion battery with high-rate charge and discharge
JP2019106352A (en) Method for producing sulfide solid-state battery
CN114497698A (en) Lithium ion battery and power utilization device
CN114335428B (en) Positive plate, preparation method and battery
KR20200028258A (en) Anode for secondary battery and Secondary battery including the same
CN111403739A (en) Nickel-cobalt-manganese acid lithium battery cell positive electrode active material, aluminum shell battery cell and manufacturing method thereof
CN113113565B (en) Negative plate and battery
CN210379259U (en) Positive plate for improving rate capability of lithium ion battery
CN218482273U (en) Current collector, electrode and battery thereof
CN110611102A (en) Current collector, pole piece, preparation method of pole piece and electrochemical energy storage device
CN216389656U (en) Lithium ion battery with novel cylindrical lug structure
CN113793972B (en) Battery and preparation method thereof
CN212571048U (en) Lithium ion battery
CN101267037A (en) High-current discharge lithium ion battery and its making method

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
RJ01 Rejection of invention patent application after publication
RJ01 Rejection of invention patent application after publication

Application publication date: 20200508