CN109524615B - Method for improving coating appearance of lithium ion battery cathode - Google Patents
Method for improving coating appearance of lithium ion battery cathode Download PDFInfo
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- CN109524615B CN109524615B CN201811283023.2A CN201811283023A CN109524615B CN 109524615 B CN109524615 B CN 109524615B CN 201811283023 A CN201811283023 A CN 201811283023A CN 109524615 B CN109524615 B CN 109524615B
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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
- H01M4/04—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
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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
- 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
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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
- H01M10/00—Secondary cells; Manufacture thereof
- H01M10/42—Methods or arrangements for servicing or maintenance of secondary cells or secondary half-cells
- H01M10/4235—Safety or regulating additives or arrangements in electrodes, separators or electrolyte
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M4/00—Electrodes
- H01M4/02—Electrodes composed of, or comprising, active material
- H01M4/62—Selection of inactive substances as ingredients for active masses, e.g. binders, fillers
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- 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
A method for improving the coating appearance of a negative electrode of a lithium ion battery comprises the following steps: adjusting the negative electrode ingredients of the lithium battery: the negative electrode ingredient comprises the following components in percentage by mass: 94-96% of negative electrode main material, 1-1.5% of conductive agent, 1.5-2% of sodium carboxymethylcellulose and 1.5-2.5% of styrene-butadiene rubber emulsion; and (3) preparing anode slurry: adding deionized water into the negative electrode ingredients, stirring, and adjusting the viscosity of the negative electrode slurry to meet the process requirement; and adding an organic solvent into the prepared cathode slurry, and stirring at a high speed, wherein the adding proportion of the organic solvent is 1.0-3.0%. According to the invention, the proportion of the negative electrode main material and the sodium carboxymethyl cellulose is adjusted, and the organic solvent is added into the negative electrode slurry after the proportion of the negative electrode main material and the sodium carboxymethyl cellulose is adjusted, so that the coating appearance of the negative electrode is effectively improved, the working efficiency is effectively improved, and the waste loss in the production process is reduced.
Description
Technical Field
The invention relates to a lithium ion battery, in particular to a method for improving the coating appearance of a negative electrode of the lithium ion battery.
Background
The current lithium ion battery is coated by extrusion coating, transfer coating and other methods, and in the coating process, the coating thickness and the surface density need to be controlled to meet the process requirements; meanwhile, the solvent in the base material slurry is removed by drying and heating in an oven, so that the solid substance is uniformly adhered to the base material.
In the coating process of the lithium battery cathode, because the volatilization speeds of the solvent on the surface of the coating solution and the solvent on the bottom layer are different, the concentration difference of the solvent content occurs, the surface tension gradient and the natural convection phenomenon of the coating are caused, and the coating appearance of the cathode is poor. In addition, in order to improve the working efficiency, if the coating speed of the negative electrode is improved, the phenomenon is more obvious, and the reject ratio of the coating appearance of the negative electrode of the lithium battery is increased.
Disclosure of Invention
The invention provides a method for improving the coating appearance of a negative electrode of a lithium ion battery, aiming at the problems in the prior art, and the invention effectively improves the coating appearance of the negative electrode by adjusting the proportion of a negative electrode main material and sodium carboxymethyl cellulose and adding an organic solvent into a negative electrode slurry after the proportion of the negative electrode main material and the sodium carboxymethyl cellulose is adjusted, thereby improving the working efficiency and reducing the waste loss generated in the production process.
The technical problem of the invention is solved by the following technical scheme:
a method of improving the coating appearance of a lithium ion battery negative electrode, the method comprising the steps of:
a. adjusting the negative electrode ingredients of the lithium battery: the negative electrode ingredient comprises the following components in percentage by mass: 94-96% of negative electrode main material, 1-1.5% of conductive agent, 1.5-2% of sodium carboxymethylcellulose and 1.5-2.5% of styrene-butadiene rubber emulsion;
b. and (3) preparing anode slurry: adding deionized water into the negative electrode ingredients, stirring, and adjusting the viscosity of the negative electrode slurry to meet the process requirement;
c. adding an organic solvent into the prepared cathode slurry, and stirring at a high speed, wherein the addition amount of the organic solvent accounts for 1.0-3.0% of the proportion of the cathode ingredients;
d. and coating the negative electrode slurry on a negative electrode plate, observing the appearance of the negative electrode plate, and recording the fraction defective.
In the step a, the negative electrode main material is graphite, and the conductive agent is conductive carbon black.
In the step b, the viscosity of the negative electrode slurry is 1000-3000mpa.s.
The method for improving the coating appearance of the lithium ion battery cathode is characterized by comprising the following steps: in the step c, the organic solvent is one of methyl pyrrolidone, ethanol or acetone.
In the lithium battery cathode ingredient, the adding proportion of the cathode main material is adjusted to 94-96%, the adding amount of the cathode main material is reduced by 0.1-0.3% compared with the adding amount of the cathode main material of the conventional ingredient, the adding proportion of the sodium carboxymethyl cellulose is adjusted to 1.5-2%, the adding amount of the sodium carboxymethyl cellulose is increased by 0.1-0.3% compared with the adding amount of the conventional ingredient, the content of the sodium carboxymethyl cellulose is increased, the dispersion and the stability of a non-hydrophilic material are facilitated, and when the cathode is coated, slurry has good fluidity, and the bad phenomenon on the coating surface of a cathode piece can be prevented; after the proportion of the negative electrode main material and the sodium carboxymethyl cellulose is adjusted, the slurry is adjusted to the concentration required by the process, the organic solvent is added into the slurry, and the adding proportion of the organic solvent is controlled to be 1.0-3.0%, so that the concentration difference of the solvent generated by the difference of the volatilization speeds of the negative electrode coating slurry surface and the bottom layer solvent can be effectively reduced, the coating surface tension gradient is reduced, and the negative electrode coating solution flows to a position with higher surface tension from lower surface tension, so that the coating appearance of the negative electrode is poor. The method has strong operability, effectively improves the coating appearance of the negative electrode, and reduces the waste rate in the production process while improving the working efficiency.
The adverse factors influencing the coating appearance of the negative electrode mainly comprise the surface cracking of the negative electrode and the dark marks on the surface of the negative electrode, wherein the judgment standard of the surface cracking of the negative electrode is that any cracking on the surface of the negative electrode is unqualified; the negative electrode surface dark marks mainly have the phenomena that dressing on the pole piece is strip-shaped, thin and inconsistent in color with surrounding dressing, the judgment standard is that the negative electrode dark marks have no obvious convex-concave hand feeling, the width is less than 2mm, the length is less than 2cm, a single mark is less than two points, and the negative electrode surface dark marks are unqualified products when the width exceeds the standard. The main reason for generating the phenomenon of poor coating appearance is that the content ratio of the sodium carboxymethylcellulose to the organic solvent is unreasonable, the adding proportion of the negative electrode main material is adjusted to be reduced by 0.1-0.3% compared with the adding proportion of the conventional auxiliary material negative electrode main material, the adding proportion of the sodium carboxymethylcellulose is increased by 0.1-0.3% compared with the conventional adding proportion, the content of the sodium carboxymethylcellulose is increased, the adding proportion of the organic solvent is controlled to be 1.0-3.0%, and the phenomenon of poor coating appearance of the negative electrode is obviously improved.
Detailed Description
The invention provides a formula of a lithium battery cathode ingredient, wherein the cathode ingredient comprises 94-96% of a cathode main material, 1-1.5% of a conductive agent, 1.5-2% of sodium carboxymethylcellulose and 1.5-2.5% of styrene-butadiene rubber emulsion.
The negative electrode main material is an active material of electrochemical reaction, the conductive agent is used for improving the conductivity of the negative electrode, the sodium carboxymethyl cellulose is mainly used as a dispersing agent and a thickening agent, and the styrene-butadiene rubber emulsion mainly changes the surface structure of particles so as to be more compatible with the negative electrode main material and the sodium carboxymethyl cellulose.
The content of the negative electrode main material is reduced, the content of sodium carboxymethylcellulose is improved, the dispersion and the stability of a non-hydrophilic material are facilitated, and the slurry has good fluidity during the coating of the negative electrode, so that the bad phenomenon on the coating surface of a negative electrode piece can be prevented; after the proportion of the negative electrode main material and the sodium carboxymethyl cellulose is adjusted, the slurry is adjusted to the concentration required by the process, the organic solvent is added into the slurry, and the adding proportion of the organic solvent is controlled to be 1.0-3.0%, so that the concentration difference of the solvent generated by the difference of the volatilization speeds of the negative electrode coating slurry surface and the bottom layer solvent can be effectively reduced, the coating surface tension gradient is reduced, and the negative electrode coating solution flows to a position with higher surface tension from lower surface tension, so that the coating appearance of the negative electrode is poor.
After the negative electrode main material and the sodium carboxymethyl cellulose are adjusted according to the formula proportion, water is added to prepare negative electrode slurry, and then an organic solvent with a certain proportion is added into the negative electrode slurry for coating.
The present invention is further illustrated by the following examples.
Example 1
Adjusting the negative electrode ingredients of the lithium battery: the negative electrode ingredient comprises the following components in percentage by mass: 94.9 percent of negative electrode main material, 1 percent of conductive agent, 1.6 percent of sodium carboxymethyl cellulose and 2.5 percent of styrene-butadiene rubber emulsion; adding deionized water into the negative electrode material, stirring, and adjusting the viscosity of the negative electrode slurry to be 1000-3000 mPa.S.; adding an organic solvent into the prepared cathode slurry, and stirring at a high speed, wherein the adding proportion of the organic solvent (one of methyl pyrrolidone, ethanol or acetone) is 1.0%; and coating the negative electrode slurry on a negative electrode plate, observing the appearance of the negative electrode plate, and recording the fraction defective.
The proportion of the main material of the negative electrode is reduced by 0.1% compared with the conventional proportion, the proportion of the sodium carboxymethyl cellulose is improved by 0.1% compared with the conventional proportion, the addition amount of the organic solvent is 1.0%, and under the condition, the defect rate of the negative electrode of the lithium battery in appearance is reduced to 0.23% from 2.8%.
Example 2
Adjusting the negative electrode ingredients of the lithium battery: the negative electrode ingredient comprises the following components in percentage by mass: 94.9 percent of negative electrode main material, 1 percent of conductive agent, 1.6 percent of sodium carboxymethyl cellulose and 2.5 percent of styrene-butadiene rubber emulsion; adding deionized water into the negative electrode material, stirring, and adjusting the viscosity of the negative electrode slurry to be 1000-3000 mPa.S.; adding an organic solvent into the prepared cathode slurry, and stirring at a high speed, wherein the adding proportion of the organic solvent (one of methyl pyrrolidone, ethanol or acetone) is 3.0%; and coating the negative electrode slurry on a negative electrode plate, observing the appearance of the negative electrode plate, and recording the fraction defective.
The proportion of the main material of the negative electrode is reduced by 0.1% compared with the conventional proportion, the proportion of the sodium carboxymethyl cellulose is improved by 0.1% compared with the conventional proportion, the addition amount of the organic solvent is 3.0%, and under the condition, the defect rate of the negative electrode of the lithium battery in appearance is reduced to 0.25% from 2.8%.
Example 3
Adjusting the negative electrode ingredients of the lithium battery: the negative electrode ingredient comprises the following components in percentage by mass: 94.7 percent of negative electrode main material, 1 percent of conductive agent, 1.8 percent of sodium carboxymethyl cellulose and 2.5 percent of styrene-butadiene rubber emulsion; adding deionized water into the negative electrode material, stirring, and adjusting the viscosity of the negative electrode slurry to be 1000-3000 mPa.S.; adding an organic solvent into the prepared cathode slurry, and stirring at a high speed, wherein the adding proportion of the organic solvent (one of methyl pyrrolidone, ethanol or acetone) is 3.0%; and coating the negative electrode slurry on a negative electrode plate, observing the appearance of the negative electrode plate, and recording the fraction defective.
The proportion of the main material of the negative electrode is reduced by 0.3 percent compared with the conventional proportion, the proportion of the sodium carboxymethyl cellulose is improved by 0.3 percent compared with the conventional proportion, the addition amount of the organic solvent is 1.0 percent, and under the condition, the defect rate of the negative electrode of the lithium battery in appearance is reduced to 0.26 percent from 2.8 percent.
Example 4
Adjusting the negative electrode ingredients of the lithium battery: the negative electrode ingredient comprises the following components in percentage by mass: 94.7 percent of negative electrode main material, 1 percent of conductive agent, 1.8 percent of sodium carboxymethyl cellulose and 2.5 percent of styrene-butadiene rubber emulsion; adding deionized water into the negative electrode material, stirring, and adjusting the viscosity of the negative electrode slurry to be 1000-3000 mPa.S.; adding an organic solvent into the prepared cathode slurry, and stirring at a high speed, wherein the adding proportion of the organic solvent (one of methyl pyrrolidone, ethanol or acetone) is 3.0%; and coating the negative electrode slurry on a negative electrode plate, observing the appearance of the negative electrode plate, and recording the fraction defective.
The proportion of the main material of the negative electrode is reduced by 0.3 percent compared with the conventional proportion, the proportion of the sodium carboxymethyl cellulose is improved by 0.3 percent compared with the conventional proportion, the addition amount of the organic solvent is 3.0 percent, and under the condition, the defect rate of the negative electrode of the lithium battery in appearance is reduced to 0.22 percent from 2.8 percent.
Claims (3)
1. A method for improving the coating appearance of a negative electrode of a lithium ion battery is characterized by comprising the following steps: after the proportion of the negative electrode main material and the sodium carboxymethyl cellulose is adjusted, and the slurry is adjusted to the viscosity required by the process, the organic solvent is added into the slurry, and the method comprises the following steps:
a. adjusting the negative electrode ingredients of the lithium battery: the negative electrode ingredient comprises the following components in percentage by mass: 94-96% of negative electrode main material, 1-1.5% of conductive agent, 1.5-2% of sodium carboxymethylcellulose and 1.5-2.5% of styrene-butadiene rubber emulsion;
b. and (3) preparing anode slurry: adding deionized water into the negative electrode ingredients, stirring, and adjusting the viscosity of the negative electrode slurry to meet the process requirement;
c. adding an organic solvent into the prepared cathode slurry, and stirring at a high speed, wherein the adding proportion of the organic solvent is 1.0-3.0%;
d. coating the negative electrode slurry on a negative electrode plate, observing the appearance of the negative electrode plate, and recording the fraction defective;
in the step c, the organic solvent is one of methyl pyrrolidone, ethanol or acetone.
2. The method of claim 1 for improving the coated appearance of a lithium ion battery negative electrode, wherein: in the step a, the main material of the negative electrode is graphite, and the conductive agent is conductive carbon black.
3. The method of claim 2, wherein the coating comprises: in the step b, the viscosity of the negative electrode slurry is 1000-3000mPa.S.
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Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2000040504A (en) * | 1998-07-21 | 2000-02-08 | Sony Corp | Manufacture of positive mix for organic electrolyte battery |
| CN101604742A (en) * | 2009-06-12 | 2009-12-16 | 珠海锂源投资有限公司 | A kind of graphite water-base cathode formula and preparation method |
| CN102790218A (en) * | 2012-08-03 | 2012-11-21 | 杭州万马高能量电池有限公司 | Preparation process for cathode paste of lithium-ion battery |
| CN103296254A (en) * | 2013-04-16 | 2013-09-11 | 江苏力天新能源科技有限公司 | Preparation method for lithium ion battery negative pole slurry |
| CN104201384A (en) * | 2014-04-19 | 2014-12-10 | 东风商用车有限公司 | A lithium ion battery anode piece and a manufacturing method thereof |
| CN107305944A (en) * | 2016-04-24 | 2017-10-31 | 万向二三股份公司 | A kind of preparation method of energy density lithium ion power battery water system negative pole |
| CN108470886A (en) * | 2018-02-05 | 2018-08-31 | 多氟多（焦作）新能源科技有限公司 | A kind of lithium ion battery anode slurry and preparation method thereof, cathode pole piece, lithium ion battery |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN102299300A (en) * | 2011-08-02 | 2011-12-28 | 无锡市明杨电池有限公司 | Manufacturing method for high-rate lithium ion battery negative electrode plates |
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Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2000040504A (en) * | 1998-07-21 | 2000-02-08 | Sony Corp | Manufacture of positive mix for organic electrolyte battery |
| CN101604742A (en) * | 2009-06-12 | 2009-12-16 | 珠海锂源投资有限公司 | A kind of graphite water-base cathode formula and preparation method |
| CN102790218A (en) * | 2012-08-03 | 2012-11-21 | 杭州万马高能量电池有限公司 | Preparation process for cathode paste of lithium-ion battery |
| CN103296254A (en) * | 2013-04-16 | 2013-09-11 | 江苏力天新能源科技有限公司 | Preparation method for lithium ion battery negative pole slurry |
| CN104201384A (en) * | 2014-04-19 | 2014-12-10 | 东风商用车有限公司 | A lithium ion battery anode piece and a manufacturing method thereof |
| CN107305944A (en) * | 2016-04-24 | 2017-10-31 | 万向二三股份公司 | A kind of preparation method of energy density lithium ion power battery water system negative pole |
| CN108470886A (en) * | 2018-02-05 | 2018-08-31 | 多氟多（焦作）新能源科技有限公司 | A kind of lithium ion battery anode slurry and preparation method thereof, cathode pole piece, lithium ion battery |
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