CN105692597A - Preparation method of carbon graphite for lithium battery - Google Patents
Preparation method of carbon graphite for lithium battery Download PDFInfo
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- CN105692597A CN105692597A CN201610038645.3A CN201610038645A CN105692597A CN 105692597 A CN105692597 A CN 105692597A CN 201610038645 A CN201610038645 A CN 201610038645A CN 105692597 A CN105692597 A CN 105692597A
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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
- H01M4/36—Selection of substances as active materials, active masses, active liquids
- H01M4/58—Selection of substances as active materials, active masses, active liquids of inorganic compounds other than oxides or hydroxides, e.g. sulfides, selenides, tellurides, halogenides or LiCoFy; of polyanionic structures, e.g. phosphates, silicates or borates
- H01M4/583—Carbonaceous material, e.g. graphite-intercalation compounds or CFx
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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
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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
- H01M4/36—Selection of substances as active materials, active masses, active liquids
- H01M4/58—Selection of substances as active materials, active masses, active liquids of inorganic compounds other than oxides or hydroxides, e.g. sulfides, selenides, tellurides, halogenides or LiCoFy; of polyanionic structures, e.g. phosphates, silicates or borates
- H01M4/583—Carbonaceous material, e.g. graphite-intercalation compounds or CFx
- H01M4/587—Carbonaceous material, e.g. graphite-intercalation compounds or CFx for inserting or intercalating light metals
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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
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Abstract
The invention relates to a preparation method of carbon graphite for a lithium battery. The method provided by the invention comprises the following steps of carrying out spheroidization processing on graphite particles to obtain spherical graphite with d50 being 15 to 25mum; mixing the prepared spherical graphite and chitosan according to the mass ratio of 100:1 to 15, and mixing in a ball mill for 60 to 300min; putting materials processed by the ball mill into a carbonized oven fed with inert gas, and carbonizing for 5 to 6h after rising the temperature to be 800 to 900 DEG C through the temperature raising rate of 2 to 10 DEG C/min; after stirring and mixing the carbonized spherical graphite with a polymer resin solution, drying at the temperature of 150 to 250 DEG C; processing the dried materials for 2 to 3 hours at the temperature of 950 to 1,150 DEG C, cooling, and crushing; graphitizing the crushed products to obtain a graphite negative electrode material. The negative electrode material prepared by the method provided by the invention has the advantages of circulatory stability, high first coulomb efficiency, and more times of stable cycle life.
Description
Technical field
The present invention relates to technical field of lithium batteries, be specifically related to a kind of lithium battery carbon graphite preparation method。
Background technology
Lithium ion battery because of its there is energy height, the advantage such as volume is little, voltage is high, life-span length is widely used in military and civilian equipment。Negative material is one of critical material of lithium ion battery, and carbonaceous material is the material of conventional lithium ion battery negative。
It is found that after entering to use and studying, in the carbon negative pole material material charge and discharge process when lithium ion battery uses, the SEI film of formation is constantly avalanche easily, affects serviceability and the life-span of battery, need its surface is modified and shaping, improve battery performance and service life。
The method of natural flake graphite processing negative material is mainly spheroidization, surface oxidation and Surface coating carbonization, graphitization。Conventional method of modifying is on spherical graphite surface by liquid phase or liquid process cladding Colophonium, then carbonization or graphitization obtain negative material under nitrogen protection。But this process cycles poor stability, electricity decay is serious。
Summary of the invention
The invention aims to overcome the drawbacks described above existed in prior art, it is provided that a kind of lithium battery carbon graphite preparation method。
For solving the problems referred to above, the present invention proposes a kind of lithium battery carbon graphite preparation method, comprises the following steps:
Step one, graphite particulate is carried out spheroidization process, obtain the spherical graphite that d50 is 15-25 μm；
Step 2, by the spherical graphite of preparation and chitosan by the mass ratio of 100:1-15 mix laggard enter ball mill mixed processing 60-300min；
Step 3, by step 2 ball mill process after material put in the carbide furnace being connected with noble gas, after rising to 800-900 DEG C with the heating rate of 2-10 DEG C/min, carbonization treatment 5-6h；
Step 4, the stirring of the spherical graphite after carbonization treatment in step 3 and high-molecular resin solution mix after, dry at 150-250 DEG C；
Step 5, material dried in step 4 is processed 2-3 hour at 950-1150 DEG C after cooling, broken；
Step 6, afterproduct broken in step 5 is carried out graphitization processing, namely obtain graphite cathode material。
In technique scheme, before implementing described step 2, spherical graphite being carried out oxidation processes, described oxidation processes is to be immersed in oxidizing agent solution 45-120 minute by spherical graphite。
In technique scheme, described oxidizing agent solution is that the concentrated sulphuric acid of 98% is mixed by the mass ratio of 1:0.5-0.8 with the potassium permanganate of 1.5-2mol/L。
In technique scheme, when carrying out oxidation processes, spherical graphite being carried out ultrasonic Treatment, the frequency of ultrasonic Treatment is 35-40KHZ, and the power of ultrasonic Treatment is 250W-300W, and the time of ultrasonic Treatment is 40-90 minute。
In technique scheme, in described step 4, high-molecular resin solution is one or more solution being configured to water or diethylene glycol in phenolic resin, epoxy resin, Colophonium。
In technique scheme, the graphitization processing in described step 6 refers to and broken afterproduct is heated to 2700 DEG C of graphitizations carried out above。
Lithium battery carbon graphite preparation method in the present invention, by spherical graphite being carried out surface modification and structural adjustment, effectively raise the specific surface area of negative material, thus promoting its chemical property, first spherical graphite is carried out oxidation processes, use chitosan that spherical graphite is coated with subsequently, pass through high-temperature heat treatment, make the organic matter volatilization of spherical graphite surface, produce micropore, macromolecule resin is used to carry out graphitization processing after carrying out secondary capsulation subsequently, formed stable, equally distributed perforated gap structure, not only increase the capacitance of negative material, also greatly strengthen spherical graphite surface and form the stability of dielectric film, and the carbon skeleton mechanical strength height formed after secondary capsulation, improve the cycle life of negative material。
Accompanying drawing explanation
Fig. 1 is the schematic flow sheet of lithium battery carbon graphite preparation method in the present invention；
Detailed description of the invention
Below in conjunction with the drawings and specific embodiments, the present invention is described in further detail:
Embodiment 1
Lithium battery carbon graphite preparation method in the present invention, as it is shown in figure 1, comprise the following steps:
Step one, the graphite particulate that grade is 1-15 μm is carried out spheroidization process, obtain the spherical graphite that d50 is 18.4 μm, taking and take out after 500g spherical graphite soaks 60 minutes in the hydrogen peroxide of 30% mass concentration, it is neutral for repeatedly cleaning spherical graphite with deionized water to cleaning water；
Step 2, spherical graphite prepared by step one mix with 40g chitosan laggard enter ball mill process 90min；
Step 3, by step 2 ball mill process after material put in the carbide furnace being connected with argon, after rising to 850 DEG C with the heating rate of 2 DEG C/min, carbonization treatment 5h；
Step 4, the spherical graphite after carbonization treatment in step 3 and 10g phenolic resin and 100g water is stirred mix 30 minutes after, dry at 150 DEG C；
Step 5, material dried in step 4 is processed 2 hours at 950 DEG C after cooling, broken；
Step 6, afterproduct broken in step 5 is carried out graphitization processing, be heated to cooling after 2800 DEG C of insulations 3 days, namely obtain graphite cathode material。
Embodiment 2
Lithium battery carbon graphite preparation method in the present invention, comprises the following steps:
The graphite particulate that step one, just grade are 1-15 μm carries out spheroidization process, obtain the spherical graphite that d50 is 18.2 μm, taking after 500g spherical graphite soaks 60 minutes in the oxidant that the concentrated sulphuric acid of 98% and the potassium permanganate of 1.5mol/L are mixed by the mass ratio of 1:0.5 and take out, it is neutral for repeatedly cleaning spherical graphite with deionized water to cleaning water；When soaking, spherical graphite being carried out ultrasonic Treatment, the frequency of ultrasonic Treatment is 35KHZ, and the power of ultrasonic Treatment is 250W, and the time of ultrasonic Treatment is 50 minutes；
Step 2, in above-mentioned spherical graphite add 75g chitosan, mix laggard enter ball mill process 120min；
Step 3, by step 2 ball mill process after material put in the carbide furnace being connected with argon, after rising to 900 DEG C with the heating rate of 3 DEG C/min, carbonization treatment 5.5h；
Step 4, by the spherical graphite after carbonization treatment in step 3 with stir after mix and blend mix with 10g epoxy resin and 90g water, dry at 200 DEG C；
Step 5, material dried in step 4 is processed 3 hours at 1000 DEG C after cooling, broken；
Step 6, afterproduct broken in step 5 is carried out graphitization processing, be heated to cooling after 2750 DEG C of insulations 4 days, namely obtain graphite cathode material。
Embodiment 3
Lithium battery carbon graphite preparation method in the present invention, comprises the following steps:
The graphite particulate that step one, just grade are 1-15 μm carries out spheroidization process, obtain the spherical graphite that d50 is 22.4 μm, taking after 300g spherical graphite soaks 90 minutes in the oxidant that the concentrated sulphuric acid of 98% and the potassium permanganate of 1.5mol/L are mixed by the mass ratio of 1:0.8 and take out, it is neutral for repeatedly cleaning spherical graphite with deionized water to cleaning water；When soaking, spherical graphite being carried out ultrasonic Treatment, the frequency of ultrasonic Treatment is 40KHZ, and the power of ultrasonic Treatment is 300W, and the time of ultrasonic Treatment is 60 minutes；
Step 2, the spherical graphite of preparation is mixed with 30g chitosan after put into ball mill process 240min；
Step 3, by step 2 ball mill process after material put in the carbide furnace being connected with argon, after rising to 800 DEG C with the heating rate of 2 DEG C/min, carbonization treatment 6h；
Step 4, the spherical graphite after carbonization treatment in step 3 and 25g phenolic resin and 100g diethylene glycol is stirred mix after, dry at 250 DEG C；
Step 5, material dried in step 4 is processed 2 hours at 1000 DEG C after cooling, broken；
Step 6, afterproduct broken in step 5 is carried out graphitization processing, be heated to cooling after 2800 DEG C of insulations 3 days, namely obtain graphite cathode material。
Embodiment 4
Lithium battery carbon graphite preparation method in the present invention, comprises the following steps:
The graphite particulate that step one, just grade are 1-15 μm carries out spheroidization process, obtain the spherical graphite that d50 is 20.7 μm, taking after 200g spherical graphite soaks 100 minutes in the oxidant that the concentrated sulphuric acid of 98% and the potassium permanganate of 2mol/L are mixed by the mass ratio of 1:0.6 and take out, it is neutral for repeatedly cleaning spherical graphite with deionized water to cleaning water；When soaking, spherical graphite being carried out ultrasonic Treatment, the frequency of ultrasonic Treatment is 35KHZ, and the power of ultrasonic Treatment is 300W, and the time of ultrasonic Treatment is 80 minutes；
Step 2, the spherical graphite of preparation is mixed with 25g chitosan after put into ball mill process 180min；
Step 3, by step 2 ball mill process after material put in the carbide furnace being connected with argon, after rising to 875 DEG C with the heating rate of 5 DEG C/min, carbonization treatment 5.5h；
Step 4, the spherical graphite after carbonization treatment in step 3 and 18g Colophonium and 100g water is stirred mix after, dry at 250 DEG C；
Step 5, material dried in step 4 is processed 2.5 hours at 950 DEG C after cooling, broken；
Step 6, afterproduct broken in step 5 is carried out graphitization processing, be heated to cooling after 2800 DEG C of insulations 3.5 days, namely obtain graphite cathode material。
The carbon negative pole material prepared in above-described embodiment 1, embodiment 2, embodiment 3, embodiment 4 is prepared into button cell respectively: be coated on Copper Foil after carbon negative pole material is added binding agent and thickening agent and make negative pole, adopt lithium paillon foil as positive pole, electrolyte solution is add 1M lithium hexafluorophosphate (LiPF6) in the diethyl carbonate (DEC) that volume ratio is 6:4 and ethylene carbonate (EC) mixed liquor to make, above-mentioned material is adopted to make button cell test performance, as shown in the table:
| Test event | Embodiment 1 | Embodiment 2 | Embodiment 3 | Embodiment 4 |
| Specific surface area m2/g | 1.8 | 2.2 | 2.1 | 2.3 |
| Tap density g/cm3 | 1.05 | 1.15 | 1.2 | 1.18 |
| Specific capacity mAh/g | 364.2 | 367.8 | 368.6 | 369.1 |
| Starting efficiency % | 93.5% | 96.2% | 97.5 | 96.4 |
| 50 cycle life % | 86.8% | 89.4 | 90.9 | 89.8 |
The advantage of the present invention is by before being combined with macromolecule resin at spherical graphite, use chitosan that soccer star's graphite is wrapped up and carbonization treatment, improve the porosity of graphite surface, subsequently macromolecule resin is coated on uniformly graphite surface, it is possible not only to prevent SEI film from coming off, improve the stability of circulation, improve coulombic efficiency first simultaneously, increase the stable circulation life-span。
The content not being described in detail in this specification belongs to the known prior art of professional and technical personnel in the field。
Claims (6)
1. a lithium battery carbon graphite preparation method, it is characterised in that comprise the following steps:
Step one, graphite particulate is carried out spheroidization process, obtain the spherical graphite that d50 is 15-25 μm；
Step 2, by the spherical graphite of preparation and chitosan by the mass ratio of 100:1-15 mix laggard enter ball mill mixed processing 60-300min；
Step 3, by step 2 ball mill process after material put in the carbide furnace being connected with noble gas, after rising to 800-900 DEG C with the heating rate of 2-10 DEG C/min, carbonization treatment 5-6h；
Step 4, the stirring of the spherical graphite after carbonization treatment in step 3 and high-molecular resin solution mix after, dry at 150-250 DEG C；
Step 5, material dried in step 4 is processed 2-3 hour at 950-1150 DEG C after cooling, broken；
Step 6, afterproduct broken in step 5 is carried out graphitization processing, namely obtain graphite cathode material。
2. lithium battery carbon graphite preparation method according to claim 1, it is characterised in that: before implementing described step 2, spherical graphite being carried out oxidation processes, described oxidation processes is to be immersed in oxidizing agent solution 45-120 minute by spherical graphite。
3. lithium battery carbon graphite preparation method according to claim 2, it is characterised in that: described oxidizing agent solution is that the concentrated sulphuric acid of 98% is mixed by the mass ratio of 1:0.5-0.8 with the potassium permanganate of 1.5-2mol/L。
4. lithium battery carbon graphite preparation method according to claim 3, it is characterized in that: when carrying out oxidation processes, spherical graphite is carried out ultrasonic Treatment, the frequency of ultrasonic Treatment is 35-40KHZ, and the power of ultrasonic Treatment is 250W-300W, and the time of ultrasonic Treatment is 40-90 minute。
5. lithium battery carbon graphite preparation method according to claim 1, it is characterised in that: in described step 4, high-molecular resin solution is one or more solution being configured to water or diethylene glycol in phenolic resin, epoxy resin, Colophonium。
6. lithium battery carbon graphite preparation method according to claim 1, it is characterised in that: the graphitization processing in described step 6 refers to and broken afterproduct is heated to 2700 DEG C of graphitizations carried out above。
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109817966A (en) * | 2019-01-07 | 2019-05-28 | 宁波维科电池有限公司 | A kind of preparation method of composite cathode material of lithium ion battery |
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- 2016-01-20 CN CN201610038645.3A patent/CN105692597B/en active Active
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109817966A (en) * | 2019-01-07 | 2019-05-28 | 宁波维科电池有限公司 | A kind of preparation method of composite cathode material of lithium ion battery |
| CN109817966B (en) * | 2019-01-07 | 2022-01-04 | 宁波维科电池有限公司 | Preparation method of lithium ion battery cathode composite material |
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