CN111613796A - Negative electrode material with negative strain material coated with silicon carbon, preparation method of negative electrode material and lithium ion battery - Google Patents
Negative electrode material with negative strain material coated with silicon carbon, preparation method of negative electrode material and lithium ion battery Download PDFInfo
- Publication number
- CN111613796A CN111613796A CN202010438061.1A CN202010438061A CN111613796A CN 111613796 A CN111613796 A CN 111613796A CN 202010438061 A CN202010438061 A CN 202010438061A CN 111613796 A CN111613796 A CN 111613796A
- Authority
- CN
- China
- Prior art keywords
- graphite
- negative
- pretreated
- negative electrode
- silicon
- 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.)
- Granted
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
- H01M4/48—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides
- H01M4/483—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides for non-aqueous cells
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B32/00—Carbon; Compounds thereof
- C01B32/20—Graphite
- C01B32/21—After-treatment
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B33/00—Silicon; Compounds thereof
- C01B33/113—Silicon oxides; Hydrates 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
- 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
-
- 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
- H01M4/624—Electric conductive fillers
- H01M4/625—Carbon or graphite
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2002/00—Crystal-structural characteristics
- C01P2002/80—Crystal-structural characteristics defined by measured data other than those specified in group C01P2002/70
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2004/00—Particle morphology
- C01P2004/01—Particle morphology depicted by an image
- C01P2004/03—Particle morphology depicted by an image obtained by SEM
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2006/00—Physical properties of inorganic compounds
- C01P2006/40—Electric properties
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02E60/10—Energy storage using batteries
Abstract
The invention provides a negative material of silicon carbon coated with a negative strain material, a preparation method thereof and a lithium ion battery, wherein the negative strain material is polyurethane foam, polytetrafluoroethylene with a microporous structure, microporous ceramic, carbon fiber, ultra-high molecular weight polyethylene, zeolite with a porous structure or alpha cristobalite which are treated by a thermo-mechanical method. Coating a silicon carbon material by using the negative strain material; the volume expansion of the silicon-carbon material is inhibited by utilizing the characteristic that the volume of a unit cell of the negative strain material is shrunk in the using process. Compared with the prior art, the invention not only improves the electrical property (including the cycle performance) of the battery, but also improves the safety performance of the battery core, and has the effect of improving overcharge, short circuit, acupuncture and the like.
Description
Technical Field
The invention belongs to the field of new energy batteries, particularly relates to the field of lithium ion battery manufacturing, and particularly relates to a negative electrode material with silicon and carbon coated by a negative strain material, a preparation method of the negative electrode material, and a lithium ion battery.
Background
The lithium ion battery as an environment-friendly battery has the advantages of high energy density, high working voltage, high safety performance, long service life and the like. The silicon carbon is a cathode material with gram capacity obviously higher than that of graphite, and has obvious help for improving the energy density of the lithium battery core, but the defect is obvious, and the silicon carbon cathode can expand to about 4 times of the original volume after being circulated for a period of time, so that the electrical property and the safety performance of the battery core are seriously influenced.
Disclosure of Invention
The invention aims to provide a negative electrode material with silicon carbon coated by a negative strain material, which solves the problem of uncontrollable expansion of a silicon carbon negative electrode of a lithium ion battery in the using process and improves the safety and the electrical property of the lithium ion battery.
The invention also aims to provide a preparation method of the negative electrode material with the negative strain material coated with the silicon carbon.
The invention also aims to provide a lithium ion battery, which is prepared by using the negative electrode material of the negative strain material coated silicon carbon.
The specific technical scheme of the invention is as follows:
the negative strain material is polyurethane foam, polytetrafluoroethylene with a microporous structure, microporous ceramic, carbon fiber, ultra-high molecular weight polyethylene, zeolite with a porous structure or alpha cristobalite which are treated by a thermo-mechanical method. Coating a silicon carbon material by using the negative strain material; the volume expansion of the silicon-carbon material is inhibited by utilizing the characteristic that the volume of a unit cell of the negative strain material is shrunk in the using process.
Polyurethane foam after thermomechanical treatment refers to: after three-dimensional compression, heating, cooling and relaxation treatment are carried out on common polyurethane foam to obtain the foam with concave cell units. The purpose of mechanical treatment is as follows: so that the treated polyurethane foam has negative poisson's ratio property. The thermo-mechanical treatment effect is as follows: the negative poisson's ratio value is about-0.7.
The above polyurethane foam, polytetrafluoroethylene having a microporous structure, microporous ceramic, carbon fiber, ultra-high molecular weight polyethylene, zeolite having a porous structure, or alpha cristobalite are commercially available products.
The invention provides a preparation method of a negative electrode material with silicon carbon coated by a negative strain material, which comprises the following steps:
1) pretreating silicon monoxide;
2) pretreating graphite;
3) mixing the silicon monoxide pretreated in the step 1) and the graphite pretreated in the step 2) with a negative strain material, and carrying out heat treatment to obtain the negative electrode material of the strain material coated silicon carbon.
Further, the step 1) of pretreating the silicon monoxide specifically comprises the following steps: calcining the silicon monoxide powder with the average particle size of 5-20 microns under the protection of nitrogen or argon, cooling to room temperature along with a furnace, putting the calcined silicon monoxide into a ball mill for ball milling, dispersing the ball-milled silicon monoxide into a potassium hydroxide solution to prepare slurry, etching on a magnetic stirrer, and washing and vacuum drying the slurry to obtain pretreated silicon monoxide;
wherein, the calcination in the step 1) refers to calcination at the temperature of 600-1500 ℃ for 0.5-10 h. The ball milling is carried out, wherein the ball material ratio is 1:1 to 3:1, and the ball milling is continuously carried out for 2 to 8 hours so as to carry out surface modification on the silicon oxide material; and dispersing the ball-milled silica in a potassium hydroxide solution with the concentration of 0.2-2M to prepare slurry, wherein the mass ratio of the silica to the potassium hydroxide solution is between 1:99 and 30: 70. Etching for 1-5 h on a magnetic stirrer at the etching temperature of 0-50 ℃, and washing and vacuum drying the slurry to obtain pretreated silicon monoxide.
Step 2) the pretreatment of graphite specifically comprises the following steps: putting graphite with a median particle size of 5-20 μm into a ball mill for ball milling, dispersing the milled graphite in a potassium hydroxide solution to prepare slurry, etching the slurry on a magnetic stirrer, and washing and vacuum-drying the slurry to obtain pretreated graphite;
in the step 2), ball milling is carried out, wherein the ball-material ratio is 1:1 to 3:1, and the ball milling is continuously carried out for 2 to 8 hours; dispersing the ball-milled graphite in a potassium hydroxide solution with the concentration of 0.2-2M to prepare slurry, wherein the mass ratio of the graphite to the potassium hydroxide solution is 1:99 to 30: 70. Etching for 1-8 h on a magnetic stirrer at 0-50 deg.C. And washing and vacuum drying the slurry to obtain the pretreated graphite.
In the step 3), the dosage ratio of the silicon monoxide pretreated in the step 1) and the graphite pretreated in the step 2) to the negative strain material is as follows: 8-10% of pretreated silicon monoxide, 2-10% of negative strain material and 80-90% of pretreated graphite by mass percentage. The cathode material with high gram capacity can be obtained by compounding graphite and silicon oxide, and the gram capacity of the cathode material prepared according to the step 3) is between 380 and 500mAh/g, which is higher than that of the traditional graphite cathode material.
The heat treatment in step 3): placing the mixed materials in a sintering device, and continuously introducing dry nitrogen or argon at a flow of 1-10m3H, keeping the temperature at 500-; the processing mode can enable the coating agent to be better combined with the material, so that the silicon-carbon negative electrode material coated with the negative strain material is obtained.
Further, the mixing in the step 3) is specifically as follows:
3-1), mixing 8-10% of pretreated silicon monoxide, 2-10% of negative strain material and 80-90% of pretreated graphite for 0.5-2h to obtain a first mixed material;
3-2) coarsely grinding the first mixed material by using a planetary ball mill to obtain a second mixed material; so as to obtain a material meeting the requirement of the subsequent process on the processing particle size;
3-3) finely grinding the second mixed material again by using a jet mill to obtain a third mixed material; so that the application requirements can be met.
The mixing in the step 3-1) is specifically as follows: stirring and mixing at room temperature, wherein the stirring speed is 800-;
the coarse grinding time in the step 3-2) is controlled to be 1-4h, and the material with the median particle size of 10-60 micrometers is obtained after coarse grinding.
And 3) controlling the fine grinding time to be 2-8h in the step 3-3), and obtaining the material with the median particle size of 5-30 microns after fine grinding.
The lithium ion battery provided by the invention is prepared by using the negative electrode material of silicon carbon coated by the negative strain material. Specifically, the lithium ion battery comprises a cathode, an anode, a diaphragm and an electrolyte, wherein the cathode is prepared from the negative electrode material of the negative strain material coated silicon carbon, and the obtained lithium ion battery has the characteristics of high capacity stability and safety.
Compared with the prior art, the invention not only improves the electrical property (including the cycle performance) of the battery, but also improves the safety performance of the battery core, and has the effect of improving overcharge, short circuit, acupuncture and the like. The negative electrode material with silicon carbon coated by the negative strain material and the conventional silicon carbon negative electrode material of the same system lithium battery core respectively have the following cycle performances: the capacity retention rate of the conventional silicon-carbon negative electrode material is 88 percent after 300 circles; the capacity retention rate of the negative electrode material with the negative strain material coated with the silicon carbon is still 90-92% in 300 circles; for an overcharge test, compared with the conventional silicon-carbon negative electrode material, the silicon-carbon negative electrode material has the advantages that the failure is delayed by 5-7% of SOC; the improved lithium ion battery cell can pass a needling test; the surface temperature of the short circuit forced discharge test was reduced by about 20 ℃.
Drawings
Fig. 1 is an SEM image of a commercial anode material for comparative example 1;
fig. 2 is an EDS diagram of a commercial anode material for comparative example 1;
fig. 3 is an SEM image of the anode material D after the coating treatment in example 1;
fig. 4 is an EDS diagram of the anode material D after the coating treatment in example 1;
FIG. 5 is a comparison of high temperature cycle performance of example 1 and comparative example 1;
FIG. 6 is a comparison of high temperature cycle performance of example 2 and comparative example 1;
FIG. 7 is a comparison of high temperature cycle performance of example 3 and comparative example 1;
FIG. 8 is an overcharge test condition of comparative example 1;
FIG. 9 shows the overcharge test conditions of example 1;
FIG. 10 shows the overcharge test conditions of example 2;
FIG. 11 shows the overcharge test conditions of example 3;
FIG. 12 shows the case of the needle punching test in comparative example 1;
FIG. 13 shows the needle stick test of example 1;
FIG. 14 shows the needle stick test of example 2;
FIG. 15 shows the needle punching test in example 3;
FIG. 16 shows the short circuit test of comparative example 1;
FIG. 17 shows the short circuit test conditions of example 1;
FIG. 18 shows the short circuit test conditions of example 2;
fig. 19 shows the short circuit test case of example 3.
Detailed Description
Example 1
The preparation method of the negative electrode material with the negative strain material coated with the silicon carbon comprises the following steps:
1) and (3) carrying out silicon monoxide pretreatment: calcining the silicon monoxide powder with the average particle size of 5-20 mu m for 2h at 1000 ℃ under the protection of nitrogen, cooling the powder to room temperature along with a furnace, and putting the calcined silicon monoxide into a ball mill for ball milling; the ball-material ratio is 1:1, grinding is continued for 8 hours, the ball-milled silicon monoxide is dispersed in potassium hydroxide solution with the concentration of 0.5M to prepare slurry, the mass ratio of the silicon monoxide to the solution is 1:9, etching is carried out on a magnetic stirrer for 2 hours at room temperature, and the slurry is washed and dried in vacuum to obtain pretreated silicon monoxide;
2) graphite pretreatment: putting the graphite with the median particle size of 5-20 mu m into a ball mill for ball milling; the ball-material ratio is 1:1, grinding is continuously carried out for 8 hours, the ball-milled graphite is dispersed in potassium hydroxide solution with the concentration of 0.5M to prepare slurry, the mass ratio of the graphite to the solution is 2:8, etching is carried out on a magnetic stirrer for 4 hours at room temperature, and the slurry is washed and dried in vacuum to obtain pretreated graphite;
3) stirring 8% of pretreated silicon monoxide, 5% of polytetrafluoroethylene with a microporous structure and 87% of pretreated graphite at room temperature, wherein the stirring speed is 1000rpm, and the mixing time is 1h to obtain a first mixed material A;
4) coarse grinding the first mixed material A by using a planetary ball mill to obtain a second mixed material B, wherein the ball-material ratio is 2:1, and the coarse grinding time is controlled to be 2 hours, so that a material with the median particle size of 10-60 micrometers is obtained;
5) carrying out fine grinding on the second mixed material B again by using a jet mill to obtain a third mixed material C, wherein the ball-material ratio is 3:1, and the fine grinding time is controlled to be 4h to obtain a material with the median particle size of 5-30 microns;
6) placing the third mixed material in a sintering furnace, and continuously introducing dry argon at the flow rate of 2m3H, keeping the temperature at 800 ℃, and continuously sintering for 4 hours; obtaining a negative electrode material D of the negative strain material coated silicon carbon;
7) the coated anode material D was compared with an uncoated commercial anode material (fig. 1, 2) by SEM (fig. 3) and EDS (fig. 4) to confirm the coating.
The lithium ion battery is prepared by using the negative electrode material of the negative strain material coated silicon carbon, and specifically comprises the following steps: and (3) preparing a 5Ah soft package battery by using a NCM523 positive pole piece with the mass ratio of 95% and a silicon-carbon negative pole piece with the mass ratio of 90% after coating treatment, and finally performing high-temperature circulation and overcharge test, needling safety test and forced short circuit test.
Wherein the 5Ah soft package manufacturing process comprises the following steps:
1) adding untreated NCM523, 2% conductive carbon black, 3% polyvinylidene fluoride and the like in a mass ratio of 95% into a stirring tank, adding an N-methyl pyrrolidone solvent, and then stirring at a high speed to prepare anode slurry;
2) coating the positive electrode slurry in the step 1) on an aluminum foil, and then baking, rolling and cutting pieces at 100 +/-5 ℃ to prepare a positive electrode piece;
3) adding 90 parts by mass of the negative electrode material D prepared in the example 1, 4 parts by mass of conductive carbon black, 3 parts by mass of styrene butadiene rubber, 3 parts by mass of sodium carboxymethylcellulose and the like into a stirring tank, adding deionized water, and then stirring at a high speed to prepare negative electrode slurry;
4) coating the negative electrode slurry in the step 3) on a copper foil, and then baking, rolling and cutting into pieces at 95 +/-5 ℃ to prepare a negative electrode piece;
5) the positive pole piece, the negative pole piece, the PE isolating film and the electrolyte are made into the soft package battery cell through the working procedures of winding, assembling, baking at 90 +/-5 ℃, welding, sealing, injecting liquid, forming and the like.
6) Taking 3 cell samples in parallel, and performing a 1C/1C cycle test at 60 ℃, wherein the cycle is 300 times, and the capacity retention rate is about 92% (shown in figure 5); another 1 sample was taken, and after full charge, overcharge test was performed according to national standard, failure occurred around 153% SOC, and the maximum surface temperature was about 465 ℃ (fig. 9). 1 sample was taken, and after full charge, the needling test was performed according to the national standard, the cell failed to react, and the maximum surface temperature was 157 deg.C (FIG. 13). 1 sample was taken, and after full charge, an external short circuit forced discharge experiment was performed with a resistance of 40 milliohms, and the maximum temperature of the cell surface was 27.6 ℃ (fig. 17).
Example 2
The preparation method of the negative electrode material with the negative strain material coated with the silicon carbon comprises the following steps:
1) and (3) carrying out silicon monoxide pretreatment: calcining the silicon monoxide powder with the average particle size of 5-20 mu m at 600 ℃ for 10h under the protection of argon, cooling the calcined silicon monoxide powder to room temperature along with a furnace, putting the calcined silicon monoxide powder into a ball mill for ball milling, wherein the ball-to-material ratio is 3:1, and continuously grinding for 6 hours; dispersing the ball-milled silica in a potassium hydroxide solution with the concentration of 0.5M to prepare slurry, wherein the mass ratio of the silica to the solution is 1:9, etching the slurry for 2 hours on a magnetic stirrer at room temperature, and washing and vacuum drying the slurry to obtain pretreated silica;
2) graphite pretreatment: putting graphite with the median particle size of 5-20 mu m into a ball mill for ball milling, wherein the ball-material ratio is 3:1, and continuously milling for 6 hours; dispersing the ball-milled graphite in a potassium hydroxide solution with the concentration of 0.5M to prepare slurry, wherein the mass ratio of the graphite to the solution is 2:8, etching the graphite on a magnetic stirrer for 4 hours at room temperature, and washing and vacuum drying the slurry to obtain pretreated graphite;
3) mixing 10% of pretreated silicon monoxide, 8% of ultrahigh molecular weight polyethylene and 82% of pretreated graphite in percentage by mass, stirring at room temperature at the stirring speed of 2000rpm for 1h to obtain a first mixed material E;
4) coarse grinding the first mixed material E by using a planetary ball mill to obtain a second mixed material F, wherein the ball-material ratio is 2:1, and the coarse grinding time is controlled to be 4h, so that a material with the median particle size of 10-60 micrometers is obtained;
5) carrying out fine grinding on the second mixed material F again by using a jet mill to obtain a third mixed material G, wherein the ball-to-material ratio is 3:1, and the fine grinding time is controlled to be 2h to obtain a material with the median particle size of 10-60 microns;
6) placing the third mixed material G in a sintering furnace, and continuously introducing dry argon at the flow rate of 1m3H, keeping the temperature at 500 ℃, and continuously sintering for 2 hours; obtaining a negative electrode material H of the negative strain material coated silicon carbon;
the lithium ion battery is prepared by using the negative electrode material H with the silicon-carbon coated negative strain material, and specifically comprises the following steps: and (3) preparing a 5Ah soft package battery by using a NCM523 positive pole piece with the mass ratio of 95% and a silicon-carbon negative pole piece with the mass ratio of 90% after coating treatment, and finally performing high-temperature circulation and needling safety tests.
Wherein the 5Ah soft package manufacturing process comprises the following steps:
1) adding untreated NCM523, 2% conductive carbon black, 3% polyvinylidene fluoride and the like in a mass ratio of 95% into a stirring tank, adding an N-methyl pyrrolidone solvent, and then stirring at a high speed to prepare anode slurry;
2) coating the positive electrode slurry in the step 1) on an aluminum foil, and then baking, rolling and cutting pieces at 100 +/-5 ℃ to prepare a positive electrode piece;
3) adding 90 parts by mass of the negative electrode material H, 4 parts by mass of conductive carbon black, 3 parts by mass of styrene butadiene rubber, 3 parts by mass of sodium carboxymethylcellulose and the like into a stirring tank, adding deionized water, and then stirring at a high speed to prepare negative electrode slurry;
4) coating the negative electrode slurry in the step 3) on a copper foil, and then baking, rolling and cutting into pieces at 95 +/-5 ℃ to prepare a negative electrode piece;
5) the positive pole piece, the negative pole piece, the PE isolating film and the electrolyte are made into the soft package battery cell through the working procedures of winding, assembling, baking at 90 +/-5 ℃, welding, sealing, injecting liquid, forming and the like.
6) Taking 3 cell samples in parallel, and performing a 1C/1C cycle test at 60 ℃, wherein the cycle is 300 times, and the capacity retention rate is about 92% (shown in figure 6); another 1 sample was taken and overcharged according to national standard after full charge, failure occurred at around 152% SOC, and the maximum surface temperature was about 477 ℃ (fig. 10). 1 sample is taken, and after full charge, the needling test is carried out according to the national standard, the electric core does not pass the reaction, and the highest surface temperature is 136 ℃ (figure 14). 1 sample was taken, and after full charge, an external short circuit forced discharge experiment was performed with a resistance of 40 milliohms, and the maximum temperature of the cell surface was 27.8 ℃ (fig. 18).
Example 3
The preparation method of the negative electrode material with the negative strain material coated with the silicon carbon comprises the following steps:
1) and (3) carrying out silicon monoxide pretreatment: calcining the silicon monoxide powder with the average particle size of 5-20 mu m at 800 ℃ for 7h under the protection of argon, cooling to room temperature along with the furnace, putting the calcined silicon monoxide into a ball mill for ball milling, wherein the ball-to-material ratio is 1:1, and continuously grinding for 6 hours; dispersing the ball-milled silicon monoxide in a potassium hydroxide solution with the concentration of 0.5M to prepare slurry, wherein the mass ratio of the silicon monoxide to the solution is 1:9, etching the solution for 2 hours on a magnetic stirrer at 20 ℃, and washing and vacuum drying the slurry to obtain pretreated silicon monoxide;
2) graphite pretreatment: putting graphite with the median particle size of 5-20 mu m into a ball mill for ball milling, wherein the ball-material ratio is 1:1, and continuously milling for 2 hours; dispersing the ball-milled graphite in a potassium hydroxide solution with the concentration of 0.5M to prepare slurry, wherein the mass ratio of the graphite to the solution is 2:8, etching the graphite on a magnetic stirrer for 4 hours at the temperature of 20 ℃, and washing and vacuum drying the slurry to obtain pretreated graphite;
3) mixing 9% of pretreated silicon monoxide, 2% of alpha-cristobalite and 89% of pretreated graphite, stirring at room temperature at the stirring speed of 1200rpm for 1h to obtain a first mixed material I;
4) coarsely grinding the first mixed material I by using a planetary ball mill to obtain a second mixed material J, wherein the ball-material ratio is 2:1, and the coarse grinding time is controlled to be 4 h;
5) carrying out fine grinding on the second mixed material J again by using a jet mill to obtain a third mixed material K, wherein the ball-to-material ratio is 3:1, and the fine grinding time is controlled to be 2 h;
6) placing the third mixed material K in a sintering furnace, and continuously introducing dry argon at the flow rate of 1m3H, keeping the temperature at 500 ℃, and continuously sintering for 2 hours; obtaining a negative electrode material L of the negative strain material coated silicon carbon;
the lithium ion battery is prepared by using the negative electrode material of the negative strain material coated silicon carbon, and specifically comprises the following steps: and (3) preparing a 5Ah soft package battery by using a NCM523 positive pole piece with the mass ratio of 95% and a silicon-carbon negative pole piece with the mass ratio of 90% after coating treatment, and finally performing high-temperature circulation and needling safety tests.
Wherein the 5Ah soft package manufacturing process comprises the following steps:
1) adding untreated NCM523, 2% conductive carbon black, 3% polyvinylidene fluoride and the like in a mass ratio of 95% into a stirring tank, adding an N-methyl pyrrolidone solvent, and then stirring at a high speed to prepare anode slurry;
2) coating the positive electrode slurry in the step 1) on an aluminum foil, and then baking, rolling and cutting pieces at 100 +/-5 ℃ to prepare a positive electrode piece;
3) adding 90 parts by mass of the negative electrode material L, 4 parts by mass of conductive carbon black, 3 parts by mass of styrene butadiene rubber, 3 parts by mass of sodium carboxymethylcellulose and the like into a stirring tank, adding deionized water, and then stirring at a high speed to prepare negative electrode slurry;
4) coating the negative electrode slurry in the step 3) on a copper foil, and then baking, rolling and cutting into pieces at 95 +/-5 ℃ to prepare a negative electrode piece;
5) the positive pole piece, the negative pole piece, the PE isolating film and the electrolyte are made into the soft package battery cell through the working procedures of winding, assembling, baking at 90 +/-5 ℃, welding, sealing, injecting liquid, forming and the like.
6) Taking 3 cell samples in parallel, and performing a 1C/1C cycle test at 60 ℃, wherein the cycle is 300 times, and the capacity retention rate is about 90% (shown in figure 7); another 1 sample was taken and overcharged according to national standard after full charge, failure occurred at around 152% SOC, and the maximum surface temperature was about 536 ℃ (fig. 11). And taking 1 sample, fully filling, performing a needling test according to national standards, and allowing the battery core to pass through smoking, wherein the highest surface temperature is 335 ℃ (FIG. 15). 1 sample was taken, and after full charge, an external short circuit forced discharge experiment was performed with a resistance of 40 milliohms, and the maximum temperature of the cell surface was 28.0 ℃ (fig. 19).
Comparative example 1
An untreated NCM523 positive pole piece with the mass ratio of 95% and a silicon-carbon negative pole piece with the mass ratio of 90% are used for manufacturing a 5Ah soft package battery, and finally a high-temperature circulation and overcharge test, a needling safety test and a forced short circuit test are carried out.
Wherein the 5Ah soft package manufacturing process comprises the following steps:
1) adding untreated NCM523, 2% conductive carbon black, 3% polyvinylidene fluoride and the like in a mass ratio of 95% into a stirring tank, adding an N-methyl pyrrolidone solvent, and then stirring at a high speed to prepare anode slurry;
2) and (3) coating the positive electrode slurry in the step (1) on an aluminum foil, and then baking, rolling and cutting pieces at 100 +/-5 ℃ to prepare the positive electrode piece.
3) Adding 90 parts by mass of a commercial silicon-carbon negative electrode material (380 type silicon-carbon material of a certain company) pole piece, 4% of conductive carbon black, 3% of styrene-butadiene rubber, 3% of sodium carboxymethylcellulose and the like into a stirring tank, adding deionized water, and then stirring at a high speed to prepare negative electrode slurry;
4) and (3) coating the negative electrode slurry in the step (3) on copper foil, and then baking, rolling and cutting into pieces at 95 +/-5 ℃ to obtain the negative electrode piece.
5) And winding the anode plate, the cathode plate, the PE isolating membrane and the electrolyte, assembling, baking at 90 +/-5 ℃, welding, sealing, injecting liquid, forming and the like to prepare the soft package battery core.
6) Taking 3 samples to carry out 60 ℃ 1C/1C cycle test, and carrying out 300 cycles to obtain a capacity retention rate of about 88% (as shown in figures 5, 6 and 7); after 1 sample is fully charged, the overcharge test is carried out according to the national standard, the failure occurs at about 147 percent of SOC, and the highest temperature of the surface is about 600 ℃ (figure 8). Taking 1 sample, fully filling, performing acupuncture test according to national standard, igniting and exploding the battery core, failing to pass the test, and keeping the highest surface temperature at 619 ℃ (FIG. 12). 1 sample was taken, and after full charge, an external short circuit forced discharge experiment was performed with a resistance of 40 milliohms, and the maximum temperature of the cell surface was 46.8 ℃ (fig. 16).
Claims (10)
1. The negative material is characterized in that the negative strain material is polyurethane foam, polytetrafluoroethylene with a microporous structure, microporous ceramic, carbon fiber, ultra-high molecular weight polyethylene, zeolite with a porous structure or alpha cristobalite which are treated by a thermo-mechanical method.
2. The preparation method of the negative electrode material with the negative strain material coated with the silicon carbon, which is characterized by comprising the following steps of:
1) pretreating silicon monoxide;
2) pretreating graphite;
3) mixing the silicon monoxide pretreated in the step 1) and the graphite pretreated in the step 2) with a negative strain material, and carrying out heat treatment to obtain the negative electrode material of the strain material coated silicon carbon.
3. The preparation method according to claim 2, wherein the step 1) of pretreating the silica is specifically: calcining the silicon monoxide powder with the average particle size of 5-20 microns under the protection of nitrogen or argon, cooling to room temperature along with a furnace, putting the calcined silicon monoxide into a ball mill for ball milling, dispersing the ball-milled silicon monoxide into a potassium hydroxide solution to prepare slurry, etching on a magnetic stirrer, and washing and vacuum drying the slurry to obtain the pretreated silicon monoxide.
4. The preparation method according to claim 2, wherein the step 2) of pretreating graphite is specifically: putting graphite with the median particle size of 5-20 mu m into a ball mill for ball milling, dispersing the milled graphite in a potassium hydroxide solution to prepare slurry, etching the slurry on a magnetic stirrer, and washing and vacuum drying the slurry to obtain the pretreated graphite.
5. The preparation method of claim 4, wherein in the step 2), the ball-milled graphite is dispersed in a potassium hydroxide solution with a concentration of 0.2M-2M to prepare a slurry, wherein the mass ratio of the graphite to the potassium hydroxide solution is between 1:99 and 30: 70.
6. The method according to claim 4 or 5, wherein in step 2), the etching is performed on a magnetic stirrer for 1h to 8h at a temperature of 0 ℃ to 50 ℃.
7. The preparation method according to claim 2, wherein in the step 3), the ratio of the amount of the pretreated silicon monoxide in the step 1) and the amount of the pretreated graphite in the step 2) to the amount of the negative strain material is as follows: 8-10% of pretreated silicon monoxide, 2-10% of negative strain material and 80-90% of pretreated graphite by mass percentage.
8. The method of claim 2, wherein the heat treatment in step 3): placing the mixed materials in a sintering device, and continuously introducing dry nitrogen or argon at a flow of 1-10m3And/h, keeping the temperature at 500-1000 ℃ and continuously sintering for 2-48 hours.
9. The method according to claim 2 or 8, wherein the mixing in step 3) is specifically:
3-1), mixing 8-10% of pretreated silicon monoxide, 2-10% of negative strain material and 80-90% of pretreated graphite for 0.5-2h to obtain a first mixed material;
3-2) coarsely grinding the first mixed material by using a planetary ball mill to obtain a second mixed material; so as to obtain a material meeting the requirement of the subsequent process on the processing particle size;
3-3) finely grinding the second mixed material again by using a jet mill to obtain a third mixed material; so that the application requirements can be met.
10. The lithium ion battery is characterized by being prepared by using the negative electrode material of the negative strain material coated silicon carbon prepared by the preparation method of any one of claims 2 to 9.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010438061.1A CN111613796B (en) | 2020-05-21 | 2020-05-21 | Negative electrode material with negative strain material coated with silicon carbon, preparation method of negative electrode material and lithium ion battery |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010438061.1A CN111613796B (en) | 2020-05-21 | 2020-05-21 | Negative electrode material with negative strain material coated with silicon carbon, preparation method of negative electrode material and lithium ion battery |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN111613796A true CN111613796A (en) | 2020-09-01 |
| CN111613796B CN111613796B (en) | 2022-07-26 |
Family
ID=72203553
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202010438061.1A Active CN111613796B (en) | 2020-05-21 | 2020-05-21 | Negative electrode material with negative strain material coated with silicon carbon, preparation method of negative electrode material and lithium ion battery |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN111613796B (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113823781A (en) * | 2021-08-23 | 2021-12-21 | 惠州锂威新能源科技有限公司 | Composite negative electrode material and preparation method thereof |
| CN114336825A (en) * | 2021-12-15 | 2022-04-12 | 东莞新能源科技有限公司 | Control method and control device for battery charging and charging equipment |
Citations (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101010820A (en) * | 2004-12-22 | 2007-08-01 | 松下电器产业株式会社 | Composite negative-electrode active material, process for producing the same and nonaqueous-electrolyte secondary battery |
| CN102637875A (en) * | 2012-04-25 | 2012-08-15 | 东华大学 | Anode material used for lithium ion battery and preparation methods thereof |
| CN103474631A (en) * | 2013-10-08 | 2013-12-25 | 深圳市贝特瑞新能源材料股份有限公司 | Silicon monoxide composite negative electrode material for lithium ion battery, preparation method and lithium ion battery |
| US20140220347A1 (en) * | 2011-08-15 | 2014-08-07 | Dow Corning Corporation | Electrode composition comprising a silicon powder and method of controlling the crystallinity of a silicon powder |
| CN106920954A (en) * | 2017-05-05 | 2017-07-04 | 北京科技大学 | A kind of preparation of porous silicon composite cathode material of graphene coated and application process |
| CN107611369A (en) * | 2017-08-11 | 2018-01-19 | 天津爱敏特电池材料有限公司 | A kind of lithium-ion battery silicon-carbon anode material and preparation method thereof |
| CN108878809A (en) * | 2018-06-11 | 2018-11-23 | 成都新柯力化工科技有限公司 | A kind of lithium cell cathode material and preparation method of semi-hollow structural ceramics |
| CN109065850A (en) * | 2018-06-29 | 2018-12-21 | 南京工业大学 | A kind of three-dimensional grapheme silicon-carbon cathode composite material and preparation method |
| CN109827681A (en) * | 2019-02-19 | 2019-05-31 | 东南大学 | A kind of flexible strain transducer and preparation method thereof containing enlarged structure |
| CN110085853A (en) * | 2019-05-30 | 2019-08-02 | 郑州中科新兴产业技术研究院 | Aoxidize sub- silicon substrate carbon negative pole material, cathode pole piece and preparation method thereof and lithium ion battery |
| JP2019220350A (en) * | 2018-06-20 | 2019-12-26 | 株式会社ダイネンマテリアル | Negative electrode material for lithium ion battery, negative electrode for lithium ion battery, and lithium ion battery |
| CN110707316A (en) * | 2019-10-16 | 2020-01-17 | 北京卫蓝新能源科技有限公司 | Silicon-based lithium ion battery cathode material and preparation method thereof |
-
2020
- 2020-05-21 CN CN202010438061.1A patent/CN111613796B/en active Active
Patent Citations (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101010820A (en) * | 2004-12-22 | 2007-08-01 | 松下电器产业株式会社 | Composite negative-electrode active material, process for producing the same and nonaqueous-electrolyte secondary battery |
| US20140220347A1 (en) * | 2011-08-15 | 2014-08-07 | Dow Corning Corporation | Electrode composition comprising a silicon powder and method of controlling the crystallinity of a silicon powder |
| CN102637875A (en) * | 2012-04-25 | 2012-08-15 | 东华大学 | Anode material used for lithium ion battery and preparation methods thereof |
| CN103474631A (en) * | 2013-10-08 | 2013-12-25 | 深圳市贝特瑞新能源材料股份有限公司 | Silicon monoxide composite negative electrode material for lithium ion battery, preparation method and lithium ion battery |
| CN106920954A (en) * | 2017-05-05 | 2017-07-04 | 北京科技大学 | A kind of preparation of porous silicon composite cathode material of graphene coated and application process |
| CN107611369A (en) * | 2017-08-11 | 2018-01-19 | 天津爱敏特电池材料有限公司 | A kind of lithium-ion battery silicon-carbon anode material and preparation method thereof |
| CN108878809A (en) * | 2018-06-11 | 2018-11-23 | 成都新柯力化工科技有限公司 | A kind of lithium cell cathode material and preparation method of semi-hollow structural ceramics |
| JP2019220350A (en) * | 2018-06-20 | 2019-12-26 | 株式会社ダイネンマテリアル | Negative electrode material for lithium ion battery, negative electrode for lithium ion battery, and lithium ion battery |
| CN109065850A (en) * | 2018-06-29 | 2018-12-21 | 南京工业大学 | A kind of three-dimensional grapheme silicon-carbon cathode composite material and preparation method |
| CN109827681A (en) * | 2019-02-19 | 2019-05-31 | 东南大学 | A kind of flexible strain transducer and preparation method thereof containing enlarged structure |
| CN110085853A (en) * | 2019-05-30 | 2019-08-02 | 郑州中科新兴产业技术研究院 | Aoxidize sub- silicon substrate carbon negative pole material, cathode pole piece and preparation method thereof and lithium ion battery |
| CN110707316A (en) * | 2019-10-16 | 2020-01-17 | 北京卫蓝新能源科技有限公司 | Silicon-based lithium ion battery cathode material and preparation method thereof |
Non-Patent Citations (6)
| Title |
|---|
| MIAO ZHANG等: "Interweaved Si@C/CNTs&CNFs composites as anode materials for Li-ion batteries", 《JOURNAL OF ALLOYS AND COMPOUNDS》 * |
| MIN YANG等: "Ultrafast synthesis of graphene nanosheets encapsulated Si nanoparticles via deflagration of energetic materials for lithium-ion batteries", 《NANO ENERGY》 * |
| 方禹声 等: "《聚氨酯泡沫塑料 第2版》", 31 August 1994 * |
| 曹湘洪: "《现代化工·冶金·材料·能源 中国工程院化工、冶金与材料工程学部第九届学术会议论文集 下》", 30 September 2012 * |
| 胡隆伟 等: "《紧固件材料手册》", 31 December 2014 * |
| 薛孟尧: "硅负极材料的改性即电化学性能的研究", 《中国优秀博硕士学位论文全文数据库（硕士）工程科技I辑》 * |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113823781A (en) * | 2021-08-23 | 2021-12-21 | 惠州锂威新能源科技有限公司 | Composite negative electrode material and preparation method thereof |
| CN114336825A (en) * | 2021-12-15 | 2022-04-12 | 东莞新能源科技有限公司 | Control method and control device for battery charging and charging equipment |
| CN114336825B (en) * | 2021-12-15 | 2023-09-15 | 东莞新能源科技有限公司 | Battery charging control method, control device and charging equipment |
Also Published As
| Publication number | Publication date |
|---|---|
| CN111613796B (en) | 2022-07-26 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN109768330B (en) | Preparation method of solid electrolyte lithium ion battery and battery | |
| CN113871604B (en) | Silicon-containing mineral-based porous silicon-carbon composite anode material and preparation method thereof | |
| CN109065858B (en) | Surface modified ternary positive electrode material, preparation method thereof and battery prepared from surface modified ternary positive electrode material | |
| CN108899522B (en) | High-capacity silicon-carbon negative electrode material, preparation method and application | |
| CN111613796B (en) | Negative electrode material with negative strain material coated with silicon carbon, preparation method of negative electrode material and lithium ion battery | |
| CN106532010B (en) | Silicon-silicon nitride-carbon composite material and preparation method and application method thereof | |
| CN112110448A (en) | Nitrogen-doped carbon and nano-silicon composite anode material and preparation method thereof | |
| CN111446429B (en) | Poly-polyanion cathode material and preparation method and application thereof | |
| CN113851609A (en) | Silicon-based negative electrode plate, preparation method thereof and all-solid-state lithium ion battery | |
| CN113823781A (en) | Composite negative electrode material and preparation method thereof | |
| CN113871724A (en) | Oxide solid electrolyte and preparation method and application thereof | |
| CN112421049A (en) | Method for preparing lithium battery silicon-carbon negative electrode material through ball milling and silicon-carbon negative electrode material | |
| CN104485440B (en) | Preparation method, product, and applications of aluminum oxide-coated lithium cobalt oxide material | |
| CN109686944B (en) | Carbon-coated lithium alloy composite electrode material and preparation method thereof | |
| CN108565431B (en) | Method for preparing silicon-carbon composite negative electrode material of lithium ion battery by taking konjac flour as carbon source | |
| CN113889609B (en) | Nitrogen-doped silicon oxide/zinc oxide/graphite/carbon composite anode material and preparation method thereof | |
| CN113903896B (en) | Secondary particle hard carbon composite material and preparation method and application thereof | |
| CN115642292A (en) | Zero-strain all-solid-state lithium-aluminum battery | |
| CN109256547A (en) | A kind of preparation method of porous graphene-lithium iron phosphate positive material | |
| CN115312843A (en) | Se-doped solid electrolyte and preparation method and application thereof | |
| CN111725512B (en) | Porous silicon-carbon composite material of lithium ion battery and preparation method and application thereof | |
| CN114873591A (en) | Low-temperature long-life natural graphite negative electrode material and preparation method and application thereof | |
| CN114050243A (en) | Nitrogen-doped synergetic conductive polymer modified silicon-carbon composite negative electrode material and preparation method thereof | |
| CN110571409B (en) | Preparation method of anode material, anode material and lithium battery | |
| CN112366363A (en) | Preparation method of high-temperature-resistant lithium ion battery |
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 | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |