CN113764621A - Composite electrode plate, preparation method and application thereof, and lithium ion battery - Google Patents

Composite electrode plate, preparation method and application thereof, and lithium ion battery Download PDF

Info

Publication number
CN113764621A
CN113764621A CN202110892895.4A CN202110892895A CN113764621A CN 113764621 A CN113764621 A CN 113764621A CN 202110892895 A CN202110892895 A CN 202110892895A CN 113764621 A CN113764621 A CN 113764621A
Authority
CN
China
Prior art keywords
active layer
coating
graphite
layer
composite electrode
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
CN202110892895.4A
Other languages
Chinese (zh)
Inventor
杨尘
汪涛
李佳
吴永钢
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.)
Shanghai Electric Guoxuan New Energy Technology Nantong Co ltd
Original Assignee
Shanghai Electric Guoxuan New Energy Technology Nantong 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 Shanghai Electric Guoxuan New Energy Technology Nantong Co ltd filed Critical Shanghai Electric Guoxuan New Energy Technology Nantong Co ltd
Priority to CN202110892895.4A priority Critical patent/CN113764621A/en
Publication of CN113764621A publication Critical patent/CN113764621A/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
    • H01M4/36—Selection of substances as active materials, active masses, active liquids
    • H01M4/362—Composites
    • H01M4/366—Composites as layered products
    • 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
    • H01M4/13—Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
    • H01M4/133—Electrodes based on carbonaceous material, e.g. graphite-intercalation compounds or CFx
    • 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
    • H01M4/1393—Processes of manufacture of electrodes based on carbonaceous material, e.g. graphite-intercalation compounds or CFx
    • 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
    • H01M4/625—Carbon or graphite
    • 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)
  • Composite Materials (AREA)
  • Battery Electrode And Active Subsutance (AREA)

Abstract

The invention discloses a composite electrode plate, a preparation method and application thereof, and a lithium ion battery. The structure of the composite electrode slice is as follows: a first active layer, a conductive carbon layer and a second active layer are coated in sequence; the active material of the first active layer and/or the second active layer is graphite and/or silicon; the thickness of the conductive carbon layer is 0.5 to 4 μm. According to the invention, the conductive carbon layer is added, so that the adhesion of the upper main material is improved, and the rate capability, the cycle performance and the energy efficiency of the battery are obviously improved even if the composite electrode plate is applied to the battery under the premise of more coating amount of the active layer.

Description

Composite electrode plate, preparation method and application thereof, and lithium ion battery
Technical Field
The invention relates to a composite electrode plate, a preparation method and application thereof, and a lithium ion battery.
Background
In recent years, with the continuous expansion of the industrial scale of the lithium ion battery and the continuous development of the related technology, the lithium ion battery has become an energy storage device of mainstream electronic products, and the application of the lithium ion battery is greatly expanded. Meanwhile, the performance requirements of people on the lithium ion battery are further improved, and the lithium ion battery is required to have excellent discharge rate and long cycle life.
The prior art CN110148708A discloses a negative plate and a lithium ion battery, wherein the first film layer is a bottom graphite coating layer close to the current collector; the second film layer is a top silicon-containing coating layer far away from the current collector; the electronic conductivity of the whole material is damaged in the repeated expansion process of the silicon material, and the lithium separation phenomenon occurs; and the silicon-containing coating can also influence the dynamics of the negative plate, so that the energy efficiency of the battery is low, the rate performance is poor, and the capacity retention rate is lower than 80% when the cycle life is up to 1000 times.
Based on the above, there is a need for a lithium ion battery with high energy efficiency, good rate capability, and excellent cycle performance.
Disclosure of Invention
The invention aims to overcome the defects that the energy efficiency of a lithium ion battery thick pole piece process battery is low and the cycle performance and the rate performance cannot be simultaneously improved in the prior art, and provides a composite electrode plate, a preparation method and application thereof and a lithium ion battery.
The invention solves the technical problems by the following scheme:
the invention provides a composite electrode plate, which is coated with a first active layer, a conductive carbon layer and a second active layer in sequence;
the active material of the first active layer and/or the second active layer is graphite and/or silicon;
the thickness of the conductive carbon layer is 0.5-4 μm.
In the present invention, it is generally known in the art that the coating means coating on both sides of the substrate of the electrode sheet.
In the present invention, the first active layer and/or the second active layer may further include a conventional conductive agent and a binder in addition to the active material according to the conventional art. The conductive agent may include conductive carbon black and/or superconducting carbon black. The binder may include carboxymethyl cellulose (CMC) and/or Styrene Butadiene Rubber (SBR).
In the present invention, the coating surface density of the first active layer can be conventional in the art, and is preferably 50 to 300g/m2More preferably 80 to 300g/m2E.g. 100g/m2Or 120g/m2. The thickness of the first active layer may be 20-600 μm, preferably 60-300 μm, such as 106 μm, 93 μm or 68 μm.
In the invention, the coating surface density of the second active layer can be 50-300 g/m2Preferably 50 to 250g/m2More preferably 80 to 250g/m2E.g. 100g/m2Or 120g/m2. The thickness of the second active layer may be 20-600 μm, such as 87 μm, 93 μm, preferably 100-200 μm, such as 106 μm.
In the present invention, the ratio of the coating areal density of the first active layer to the second active layer may be conventional in the art, and is preferably 2: 5-5: 2, e.g. 1.5:1, 1:1 or 1: 1.5.
In general, the coating areal density means the density per unit area, that is, the areal density is the coating weight per coating area.
In the present invention, the graphite may be natural graphite and/or artificial graphite, which are conventional in the art.
Wherein, the natural graphite can be the conventional natural graphite in the field, and preferably, the following technical indexes are met: the carbon content is more than 99%.
Wherein, the artificial graphite can be the conventional artificial graphite in the field, and is preferablyThe following technical indexes are met: d50 particle size of 8-15 μm and tap density of 0.8-1.1g/cm3Specific surface area of 1-5m2/g。
In the present invention, when the active material contains natural graphite, the content of the natural graphite is preferably 0 to 100 wt%, and is not 0, more preferably 0 to 50 wt%, further more preferably 30 to 50 wt%, for example 48 wt%.
In the present invention, when the active material contains artificial graphite, the content of the artificial graphite is preferably 0 to 100 wt%, and is not 0, more preferably 0 to 50 wt%, further more preferably 30 to 50 wt%, for example 48 wt%.
In the invention, when the active material contains artificial graphite and natural graphite, the mass ratio of the natural graphite to the artificial graphite is 3: 7-1: 1.
In a preferred embodiment, the mass ratio of the natural graphite to the artificial graphite in the first active layer is 1:1 or 3: 7; the mass ratio of the natural graphite to the artificial graphite in the second active layer is 1:1.
In the present invention, the coating thickness of the conductive carbon layer is preferably 1 to 4 μm, for example, 2 μm.
In the present invention, the coating surface density of the conductive carbon layer is preferably 5 to 30g/m2E.g. 20g/m2Or 10g/m2。
In the present invention, the components in the conductive carbon layer include a carbon material and a binder.
Wherein, the content of the carbon material is preferably 40 to 60 wt%, more preferably 50 to 60 wt%, and the wt% is the weight percentage of the carbon material to the sum of the components in the conductive carbon layer.
Wherein, the content of the adhesive is preferably 40-60%, and the wt% refers to the weight percentage of the adhesive in the sum of the components in the conductive carbon layer.
The carbon material may include, among others, materials that are conventional in the art and capable of providing a carbon source, such as one or more of superconducting carbon black (SP), superconducting graphite (KS6), Carbon Nanotubes (CNTs), and single-walled carbon nanotubes (SWCNT). Preferably superconducting carbon black and/or superconducting graphite.
The binder may include, among others, a binder conventional in the art, such as one or more of sodium carboxymethylcellulose (CMC), Styrene Butadiene Rubber (SBR), acrylic, polyurethane, epoxy, and alkyd. Preferably acrylic and/or polyurethane.
The invention also provides a preparation method of the composite electrode plate, which comprises the step of coating the coating slurry of the first active layer, the coating slurry of the conductive carbon layer and the coating slurry of the second active layer on an electrode substrate in sequence.
As known to those skilled in the art, the preparation method of the electrode sheet generally comprises the following steps: after the coating slurry of the first active layer, the coating slurry of the conductive carbon layer, and the coating slurry of the second active layer are coated, respectively drying is performed, that is, the whole coating process is dried 3 times in total.
Preferably, the preparation method of the electrode plate comprises the following steps: coating the coating slurry of the first active layer and then drying; and then, respectively coating the coating slurry of the conductive carbon layer and the coating slurry of the second active layer, and then drying, namely, drying for 2 times in the whole coating process. This reduces the cost and increases the effectiveness of the adhesion.
The drying operations and conditions may be conventional in the art. The drying temperature can be 80-120 ℃. The drying time can be 0.5-2 h.
Wherein the solid content ratio of the coating slurry of the first active layer and/or the coating slurry of the second active layer may be conventional in the art, for example, 35% to 65%.
The solid content ratio of the coating slurry of the conductive carbon layer may be conventional in the art, for example, 40% to 50%, for example, 48%.
The invention also provides an application of the composite electrode plate in a battery.
The invention also provides a lithium ion battery which comprises the electrode plate.
On the basis of the common knowledge in the field, the above preferred conditions can be combined randomly to obtain the preferred embodiments of the invention.
The reagents and starting materials used in the present invention are commercially available.
The positive progress effects of the invention are as follows: according to the invention, the conductive carbon layer is added, so that the adhesion of the upper main material is improved, and the rate capability, the cycle performance and the energy efficiency of the battery are obviously improved even if the composite electrode plate is applied to the battery under the premise of more coating amount of the active layer.
Drawings
Fig. 1 is a schematic view of the composite electrode sheet prepared in example 1.
Fig. 2 is a graph showing rate performance of batteries manufactured using the composite electrode sheets of example 1 and comparative example 1.
Fig. 3 is a graph showing cycle performance of batteries fabricated using the composite electrode sheets of example 1 and comparative example 1.
Detailed Description
The invention is further illustrated by the following examples, which are not intended to limit the scope of the invention. The experimental methods without specifying specific conditions in the following examples were selected according to the conventional methods and conditions, or according to the commercial instructions.
In the following examples and comparative examples,
the carbon content of the natural graphite is more than 99 percent; the technical indexes of the artificial graphite are that the D50 particle size is 8-15 mu m, and the tap density is 0.8-1.1g/cm3Specific surface area of 1-5m2/g。
The adhesion test adopts a Shenzhen Meitess CMT4104 type universal tensile machine for testing.
Example 1
(1) Preparation of composite cathode electrode plate
First active layer: adopting a conventional water system slurry formula, mixing natural graphite and artificial graphite according to the mass ratio of 1:1, wherein the solid content of the graphite material of the natural graphite and the artificial graphite is 56%; the other components and contents are respectively 1% of conductive carbon black, 1.2% of CMC and 1.8% of SBR, so as to obtain a first slurry;
conductive carbon layer: mixing SP, KS-6, acrylic acid and polyurethane according to the mass ratio of 1:1:1.5:0.5 to obtain a second slurry, wherein the solid content ratio is 48%;
a second active layer: the formula is the same as that of the first active layer and is marked as third slurry.
The first slurry was coated on a copper foil substrate of 8 μm with an areal density of 120g/m2Drying and then preserving the coating thickness to be 106 mu m; coating the second slurry on the dried pole piece with a coating thickness of 2 μm and a coating density of 20g/m2(ii) a Then according to the coating surface density of 80g/m2Coating the third slurry to 87 μm, drying, and rolling to obtain negative plate (shown in figure 1), drying for 2 times, and rolling to compact density of 1.55g/cm3The drying conditions in this example were 80 ℃ and 1 hour. The adhesion was measured to be 12.5N/m.
(2) Preparation of positive plate
Preparing a positive pole piece by adopting a conventional positive pole formula, mixing a positive pole material comprising a ternary positive pole, SP, CNTs and PVDF according to a mass ratio of 97:0.5:0.5:2 to prepare a positive pole slurry, coating the positive pole slurry on an aluminum foil with the thickness of 12 mu m, drying after coating, and rolling and compacting to 3.50g/cm3And obtaining the positive plate.
(3) Preparing a lithium ion battery: the electrolyte is prepared by adopting a conventional electrolyte formula, using LiPF6 as a lithium salt, using a mixture of ethylene carbonate, propylene carbonate and dimethyl carbonate as a solvent, and adding a conventional electrolyte additive. The diaphragm adopted is a single-sided ceramic diaphragm with the thickness of 16 mu m, and the ceramic layer has the thickness of 4 mu m. And winding the positive plate, the negative plate and the diaphragm to prepare a battery core, packaging the battery core by using a metal aluminum shell, baking the battery core for 24 hours at the temperature of 120 ℃ under the protection of nitrogen, cooling the battery core, injecting electrolyte, performing formation and sorting and other processes to finally obtain the 5Ah soft package lithium ion battery.
Example 2
(1) Preparation of composite cathode electrode plate
First active layer: adopting a conventional water system slurry formula and natural graphite, wherein the solid content ratio of the graphite material is 56%; the other components and contents are respectively 1% of conductive carbon black, 1.2% of CMC and 1.8% of SBR, so as to obtain a first slurry;
conductive carbon layer: mixing SP, KS-6, acrylic acid and polyurethane according to the mass ratio of 1:1:1.5:0.5 to obtain a second slurry, wherein the solid content ratio is 48%;
a second active layer: the difference from the formula of the first active layer is that the mass ratio of the natural graphite to the artificial graphite is 1:1, and the formula of the natural graphite to the artificial graphite is marked as third slurry.
The first slurry was coated on a copper foil substrate of 8 μm with an areal density of 100g/m2After drying, the coating thickness is 93 mu m; coating the second slurry on the dried pole piece with a coating thickness of 2 μm and a coating density of 20g/m2(ii) a Finally according to the coating surface density of 100g/m2Coating the third slurry with a coating thickness of 93 μm, drying, and rolling to obtain negative plate, drying for 2 times, and rolling to compact density of 1.55g/cm3The drying condition in this example was 80 ℃ and the adhesion test for 1 hour of drying was 11.8N/m.
(2) Preparation of positive plate
Preparing a positive pole piece by adopting a conventional positive pole formula, wherein positive pole materials comprise a ternary positive pole, SP, CNTs and PVDF, mixing the three materials to prepare positive pole slurry, coating the positive pole slurry on an aluminum foil with the thickness of 12 mu m, drying after coating, and rolling and compacting to 3.50g/cm3And obtaining the positive plate.
(3) Preparing a lithium ion battery: the electrolyte is prepared by adopting a conventional electrolyte formula, using LiPF6 as a lithium salt, using a mixture of ethylene carbonate, propylene carbonate and dimethyl carbonate as a solvent, and adding a conventional electrolyte additive. The diaphragm adopted is a single-sided ceramic diaphragm with the thickness of 16 mu m, and the ceramic layer has the thickness of 4 mu m. And winding the positive plate, the negative plate and the diaphragm to prepare a battery core, packaging the battery core by using a metal aluminum shell, baking the battery core for 24 hours at the temperature of 120 ℃ under the protection of nitrogen, cooling the battery core, injecting electrolyte, performing formation and sorting and other processes to finally obtain the 5Ah soft package lithium ion battery.
Example 3
(1) Preparation of composite cathode electrode plate
First active layer: by adopting a conventional water system slurry formula, the mass ratio of the natural graphite to the artificial graphite is 6: 4, the solid content ratio of the graphite material is 56 percent; the other components and contents are respectively 1% of conductive carbon black, 1.2% of CMC and 1.8% of SBR, so as to obtain a first slurry;
conductive carbon layer: mixing SP, KS-6, acrylic acid and polyurethane according to the mass ratio of 1:1:1.5:0.5 to obtain a second slurry, wherein the solid content ratio is 48%;
a second active layer: the difference from the formula of the first active layer is that the mass ratio of the natural graphite to the artificial graphite is 1:1, and the formula of the natural graphite to the artificial graphite is marked as third slurry.
The first slurry was coated on a copper foil substrate of 8 μm with an areal density of 80g/m2Drying and storing, wherein the coating thickness is 68 mu m; then coating the second slurry on the dried pole piece with the coating thickness of 1 mu m and the coating density of 10g/m2(ii) a Finally, the coating surface density is 120g/m2Coating the third slurry with the coating thickness of 106 mu m, drying and rolling the third slurry to prepare the negative plate, and drying the negative plate for 2 times in total, wherein the rolling compaction density is 1.55g/cm3The drying condition in this example was 80 ℃ and the adhesion test for 1 hour of drying was 11.8N/m.
(2) Preparation of positive plate
Preparing a positive pole piece by adopting a conventional positive pole formula, wherein positive pole materials comprise a ternary positive pole, SP, CNTs and PVDF, mixing the three materials to prepare positive pole slurry, coating the positive pole slurry on an aluminum foil with the thickness of 12 mu m, drying after coating, and rolling and compacting to 3.50g/cm3And obtaining the positive plate.
(3) Preparing a lithium ion battery: the electrolyte is prepared by adopting a conventional electrolyte formula, using LiPF6 as a lithium salt, using a mixture of ethylene carbonate, propylene carbonate and dimethyl carbonate as a solvent, and adding a conventional electrolyte additive. The diaphragm adopted is a single-sided ceramic diaphragm with the thickness of 16 mu m, and the ceramic layer has the thickness of 4 mu m. And winding the positive plate, the negative plate and the diaphragm to prepare a battery core, packaging the battery core by using a metal aluminum shell, baking the battery core for 24 hours at the temperature of 120 ℃ under the protection of nitrogen, cooling the battery core, injecting electrolyte, performing formation and sorting and other processes to finally obtain the 5Ah soft package lithium ion battery.
Comparative example 1
(1) By adopting a conventional water system slurry formula, mixing natural graphite and artificial graphite (produced by Shenzhen) according to a mass ratio of 1:1, wherein the solid content ratio of the graphite material of the natural graphite and the artificial graphite is 96%; the other components and contents are respectively 1% of conductive carbon black, 1.2% of CMC and 1.8% of SBR, so as to obtain a first slurry;
(2) the first slurry was coated on a copper foil substrate of 8 μm with an areal density of 120g/m2Drying; according to a coating surface density of 80g/m2Coating, drying and rolling the second slurry to prepare the negative plate, wherein the rolling compaction density is 1.55g/cm3The adhesion force is 3.6N/m by adopting a Shenzhen Meitess CMT4104 type universal tensile machine for testing.
(2) Preparation of positive plate
Preparing a positive pole piece by adopting a conventional positive pole formula, mixing a positive pole material comprising a ternary positive pole, SP, CNTs and PVDF according to a mass ratio of 97:0.5:0.5:2 to prepare a positive pole slurry, coating the positive pole slurry on an aluminum foil with the thickness of 12 mu m, drying after coating, and rolling and compacting to 3.50g/cm3And obtaining the positive plate.
(3) Preparing a lithium ion battery: the electrolyte is prepared by adopting a conventional electrolyte formula, using LiPF6 as a lithium salt, using a mixture of ethylene carbonate, propylene carbonate and dimethyl carbonate as a solvent, and adding a conventional electrolyte additive. The diaphragm adopted is a single-sided ceramic diaphragm with the thickness of 16 mu m, and the ceramic layer has the thickness of 4 mu m. And winding the positive plate, the negative plate and the diaphragm to prepare a battery core, packaging the battery core by using a metal aluminum shell, baking the battery core for 24 hours at the temperature of 120 ℃ under the protection of nitrogen, cooling the battery core, injecting electrolyte, performing formation and sorting and other processes to finally obtain the 5Ah soft package lithium ion battery.
Effects of the embodiment
(1) Test of discharge Rate
The batteries prepared in example 1 and comparative example 1 were tested for charge and discharge capacity and charge and discharge energy at charge/discharge rates of 0.2C, 0.5C and 1C, respectively, with the discharge energy/charge energy being energy efficiency, to obtain a rate performance graph (the ordinate data in the graph is discharge capacity) as shown in fig. 2. As shown in fig. 2 and table 1, the rate performance, energy efficiency, cycle performance, etc. of example 1 at each discharge rate were better than those of comparative example 1.
TABLE 1
Figure BDA0003196802290000081
Figure BDA0003196802290000091
(2) Testing of cycle Performance
The batteries prepared in example 1 and comparative example are cycled for 900 weeks under the condition of 1C/1C, and a cycle performance graph is obtained as shown in FIG. 3, as can be seen from FIG. 3, the capacity retention rate of comparative example 1 is 96.8%, the capacity retention rate of example 1 is 97.5%, and the cycle performance of example 1 is improved to a certain extent at the time of 900 cycles.

Claims (10)

1. A composite electrode sheet is characterized in that a first active layer, a conductive carbon layer and a second active layer are sequentially coated on the composite electrode sheet;
the active material of the first active layer and/or the second active layer is graphite and/or silicon;
the thickness of the conductive carbon layer is 0.5-4 μm.
2. The composite electrode sheet according to claim 1, wherein the first active layer and/or the second active layer contains a conductive agent and a binder in addition to the active material;
the conductive agent preferably comprises conductive carbon black and/or superconducting carbon black;
the binder preferably comprises carboxymethyl cellulose and/or styrene-butadiene rubber.
3. The composite electrode sheet according to claim 1, wherein the first active layer has a coating surface density of 50 to 300g/m2Preferably 80 to 300g/m2E.g. 100g/m2Or 120g/m2；
And/or the coating surface density of the second active layer is 50-300 g/m2Compared withPreferably 50 to 250g/m2More preferably 80 to 250g/m2E.g. 100g/m2Or 120g/m2；
And/or the thickness of the first active layer is 20-600 μm, preferably 60-300 μm, such as 106 μm, 93 μm or 68 μm;
and/or the thickness of the second active layer is 20-600 μm, such as 87 μm, 93 μm or 106 μm, preferably 100-200 μm;
or, the ratio of the coating surface density of the first active layer to the second active layer is 2: 5-5: 2, e.g. 1.5:1, 1:1 or 1: 1.5.
4. The composite electrode sheet of claim 1, wherein the graphite is natural graphite and/or artificial graphite;
the natural graphite preferably satisfies the following technical criteria: the carbon content is more than 99 percent;
the artificial graphite preferably satisfies the following technical criteria: d50 particle size of 8-15 μm and tap density of 0.8-1.1g/cm3Specific surface area of 1-5m2/g。
5. The composite electrode sheet of claim 1,
when the active material contains natural graphite, the content of the natural graphite is 0 to 100 wt% and is not 0, preferably 0 to 50 wt%, more preferably 30 to 50 wt%, for example 48 wt%;
when the active material contains artificial graphite, the content of the artificial graphite is preferably 0 to 100 wt%, and is not 0, more preferably 0 to 50 wt%, further more preferably 30 to 50 wt%, for example 48 wt%;
preferably, when the active material contains artificial graphite and natural graphite, the mass ratio of the natural graphite to the artificial graphite is 3: 7-1: 1;
more preferably, the mass ratio of the natural graphite to the artificial graphite in the first active layer is 1:1 or 3: 7; the mass ratio of the natural graphite to the artificial graphite in the second active layer is 1:1.
6. The composite electrode sheet according to claim 1, wherein the conductive carbon layer is applied to a thickness of 1 to 4 μm, for example 2 μm;
and/or the coating surface density of the conductive carbon layer is 5-30g/m2E.g. 20g/m2Or 10g/m2；
And/or, the components in the conductive carbon layer comprise a carbon material and a binder;
wherein, the content of the carbon material is preferably 40 to 60 wt%, more preferably 50 to 60 wt%; the carbon material preferably comprises one or more of superconducting carbon black, superconducting graphite, carbon nanotubes and single-walled carbon nanotubes, more preferably superconducting carbon black and/or superconducting graphite;
wherein, the content of the adhesive is preferably 40 to 60 percent; the binder preferably comprises one or more of sodium carboxymethylcellulose, styrene butadiene rubber, acrylic, polyurethane, epoxy and alkyd resins, more preferably acrylic and/or polyurethane.
7. The preparation method of the composite electrode sheet according to any one of claims 1 to 6, wherein the coating slurry of the first active layer, the coating slurry of the conductive carbon layer and the coating slurry of the second active layer are sequentially coated on an electrode substrate.
8. The method for manufacturing a composite electrode sheet according to claim 7, comprising the steps of: after the coating slurry of the first active layer, the coating slurry of the conductive carbon layer and the coating slurry of the second active layer are coated, respectively drying;
preferably, the preparation method of the electrode plate comprises the following steps: coating the coating slurry of the first active layer and then drying; coating the coating slurry of the conductive carbon layer and the coating slurry of the second active layer respectively and then drying;
the drying temperature is preferably 80-120 ℃;
the drying time is preferably 0.5-2 h;
wherein, the solid content of the coating slurry of the first active layer and/or the coating slurry of the second active layer is preferably 35 to 65 percent;
the solid content of the coating slurry of the conductive carbon layer is preferably 40% to 50%, for example, 48%.
9. Use of the composite electrode sheet as defined in any one of claims 1 to 6 in a battery.
10. A lithium ion battery comprising the composite electrode sheet according to any one of claims 1 to 6.
CN202110892895.4A 2021-08-04 2021-08-04 Composite electrode plate, preparation method and application thereof, and lithium ion battery Pending CN113764621A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202110892895.4A CN113764621A (en) 2021-08-04 2021-08-04 Composite electrode plate, preparation method and application thereof, and lithium ion battery

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202110892895.4A CN113764621A (en) 2021-08-04 2021-08-04 Composite electrode plate, preparation method and application thereof, and lithium ion battery

Publications (1)

Publication Number Publication Date
CN113764621A true CN113764621A (en) 2021-12-07

Family

ID=78788540

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202110892895.4A Pending CN113764621A (en) 2021-08-04 2021-08-04 Composite electrode plate, preparation method and application thereof, and lithium ion battery

Country Status (1)

Country Link
CN (1) CN113764621A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114300656A (en) * 2021-12-30 2022-04-08 上海兰钧新能源科技有限公司 Preparation method of negative plate, negative plate and application of negative plate
CN115064659A (en) * 2022-08-19 2022-09-16 江苏正力新能电池技术有限公司 Composite negative plate and preparation method and application thereof

Citations (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH08153514A (en) * 1994-11-28 1996-06-11 Ricoh Co Ltd Film-shaped negative electrode for nonaqueous electrolyte secondary battery, and nonaqueous electrolyte secondary battery using same
CN102623702A (en) * 2012-03-19 2012-08-01 宁德新能源科技有限公司 Li-ion battery as well as cathode plate and preparation method thereof
CN103094619A (en) * 2013-01-17 2013-05-08 北京好风光储能技术有限公司 High-energy density lithium ion battery cell and preparation method thereof
KR20140026856A (en) * 2012-08-23 2014-03-06 삼성에스디아이 주식회사 Negative electrode for lithium secondary battery and lithium secondary battery comprising the same
CN103633293A (en) * 2013-11-08 2014-03-12 鲍添增 Lithium ion battery negative electrode piece using hard carbon and soft carbon as active materials and lithium ion battery
CN105990580A (en) * 2015-02-12 2016-10-05 深圳市比克电池有限公司 Negative electrode material, and negative plate of lithium ion battery and preparation method thereof
CN106159266A (en) * 2016-08-31 2016-11-23 合肥国轩高科动力能源有限公司 Preparation method of negative electrode slurry for reducing expansion of lithium ion battery
CN108011074A (en) * 2017-10-31 2018-05-08 合肥国轩高科动力能源有限公司 Preparation method of pole piece for improving safety performance of lithium titanate battery
CN108701816A (en) * 2016-09-29 2018-10-23 株式会社Lg化学 Multilayer cathode including natural graphite and artificial graphite and the lithium secondary battery for including the multilayer cathode
CN109698077A (en) * 2018-12-28 2019-04-30 上海奥威科技开发有限公司 A kind of multilayer negative electrode tab and preparation method thereof and supercapacitor
CN109817946A (en) * 2019-03-01 2019-05-28 湖北锂诺新能源科技有限公司 Multilayer silicium cathode material and preparation method thereof and lithium ion battery
CN110660965A (en) * 2019-08-29 2020-01-07 孚能科技(赣州)股份有限公司 Negative plate and preparation method thereof, lithium ion battery and preparation method and application thereof
CN113193203A (en) * 2021-04-14 2021-07-30 上海大学(浙江·嘉兴)新兴产业研究院 Silicon-carbon negative plate, preparation method thereof and lithium ion battery

Patent Citations (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH08153514A (en) * 1994-11-28 1996-06-11 Ricoh Co Ltd Film-shaped negative electrode for nonaqueous electrolyte secondary battery, and nonaqueous electrolyte secondary battery using same
CN102623702A (en) * 2012-03-19 2012-08-01 宁德新能源科技有限公司 Li-ion battery as well as cathode plate and preparation method thereof
KR20140026856A (en) * 2012-08-23 2014-03-06 삼성에스디아이 주식회사 Negative electrode for lithium secondary battery and lithium secondary battery comprising the same
CN103094619A (en) * 2013-01-17 2013-05-08 北京好风光储能技术有限公司 High-energy density lithium ion battery cell and preparation method thereof
CN103633293A (en) * 2013-11-08 2014-03-12 鲍添增 Lithium ion battery negative electrode piece using hard carbon and soft carbon as active materials and lithium ion battery
CN105990580A (en) * 2015-02-12 2016-10-05 深圳市比克电池有限公司 Negative electrode material, and negative plate of lithium ion battery and preparation method thereof
CN106159266A (en) * 2016-08-31 2016-11-23 合肥国轩高科动力能源有限公司 Preparation method of negative electrode slurry for reducing expansion of lithium ion battery
CN108701816A (en) * 2016-09-29 2018-10-23 株式会社Lg化学 Multilayer cathode including natural graphite and artificial graphite and the lithium secondary battery for including the multilayer cathode
CN108011074A (en) * 2017-10-31 2018-05-08 合肥国轩高科动力能源有限公司 Preparation method of pole piece for improving safety performance of lithium titanate battery
CN109698077A (en) * 2018-12-28 2019-04-30 上海奥威科技开发有限公司 A kind of multilayer negative electrode tab and preparation method thereof and supercapacitor
CN109817946A (en) * 2019-03-01 2019-05-28 湖北锂诺新能源科技有限公司 Multilayer silicium cathode material and preparation method thereof and lithium ion battery
CN110660965A (en) * 2019-08-29 2020-01-07 孚能科技(赣州)股份有限公司 Negative plate and preparation method thereof, lithium ion battery and preparation method and application thereof
WO2021037266A1 (en) * 2019-08-29 2021-03-04 孚能科技(赣州)股份有限公司 Negative plate and manufacturing method thereof and lithium ion battery as well as preparation method and application thereof
CN113193203A (en) * 2021-04-14 2021-07-30 上海大学(浙江·嘉兴)新兴产业研究院 Silicon-carbon negative plate, preparation method thereof and lithium ion battery

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
沈晓辉等: "涂炭铜箔在硅基锂离子电池中的应用研究", 《陕西煤炭》 *

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114300656A (en) * 2021-12-30 2022-04-08 上海兰钧新能源科技有限公司 Preparation method of negative plate, negative plate and application of negative plate
CN115064659A (en) * 2022-08-19 2022-09-16 江苏正力新能电池技术有限公司 Composite negative plate and preparation method and application thereof

Similar Documents

Publication Publication Date Title
WO2022116588A1 (en) Lithium-supplementing negative electrode piece, preparation method therefor and lithium ion battery
CN112271271B (en) Negative plate, preparation method, lithium ion battery core, lithium ion battery pack and application of lithium ion battery pack
CN112750976B (en) Lithium battery core and lithium ion battery
WO2018107743A1 (en) Positive pole piece of lithium ion battery, preparation method therefor and battery using same
WO2022267534A1 (en) Lithium metal negative electrode plate, electrochemical apparatus, and electronic device
CN115295791A (en) Secondary battery, and battery module, battery pack, and device each including same
CN109585781A (en) A kind of lithium ion battery negative electrode and the lithium ion battery using the pole piece
CN211045593U (en) Elastic layered silicon-based negative electrode plate and lithium battery comprising same
CN112002883A (en) Silicon-based composite material for negative electrode active material, negative electrode plate and lithium ion battery
CN112242551B (en) Secondary battery
CN109687014A (en) A kind of high-energy density fast charging type lithium-ion-power cell
WO2014071717A1 (en) Silicon negative-electrode plate of lithium ion battery, preparation method therefor, and lithium ion battery
US20120196184A1 (en) Nonaqueous electrolyte secondary battery
CN110993891A (en) Silicon-containing negative plate, preparation method thereof and lithium ion battery
CN102332558A (en) Lithium ion battery and anode pole piece thereof
CN113066954B (en) Negative plate and application thereof
CN111799470B (en) Positive pole piece and sodium ion battery
CN111129428A (en) Multilayer positive plate electrode structure, preparation method thereof and positive and negative battery structure
CN113764621A (en) Composite electrode plate, preparation method and application thereof, and lithium ion battery
KR20190077319A (en) Porous silicon material and conductive polymeric binder electrode
WO2018059180A1 (en) High-power, high-energy chemical power supply and preparation method therefor
CN114122357A (en) Lithium salt-coated graphene-doped silicon-carbon composite material and preparation method thereof
CN109428051A (en) Lithium ion battery and positive plate thereof
CN111293274A (en) Negative pole piece, preparation method thereof and lithium ion battery
CN110176598B (en) Negative electrode material of lithium ion battery and preparation method thereof

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: 20211207