CN107098326B - A kind of power lithium-ion battery hard carbon cathode material and preparation method thereof - Google Patents
A kind of power lithium-ion battery hard carbon cathode material and preparation method thereof Download PDFInfo
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- CN107098326B CN107098326B CN201710163528.4A CN201710163528A CN107098326B CN 107098326 B CN107098326 B CN 107098326B CN 201710163528 A CN201710163528 A CN 201710163528A CN 107098326 B CN107098326 B CN 107098326B
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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
- 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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Abstract
The present invention provides a kind of power lithium-ion battery low specific surface area hard carbon cathode material and preparation method thereof, which is to be prepared using organic polymer as raw material by coarse crushing, the pre-heat treatment, fine crushing, classification, surface cladding, carbonization technique.Hard carbon cathode material reversible capacity prepared by the present invention is higher than 500mAh/g, and pole piece is compacted up to 1.55g/cc, and first charge discharge efficiency is more than 2000 weeks higher than 80%, the 5C charge-discharge cycle service life.
Description
Technical field
It is the present invention relates to a kind of power lithium-ion battery negative electrode material and preparation method thereof, in particular to a kind of low to compare table
Hard carbon cathode material of area and preparation method thereof.
Background technique
High capacity and high magnification are the pursuit directions of lithium ion battery negative material for a long time, develop high magnification cathode material
Material has particularly important value, electric tool, electric car, model plane, start and stop power supply etc. to the applications expanding of lithium ion battery
Field is the application category of high-multiplying power lithium ion battery.
Traditional graphite cathode material, since its lithium ion tunnel is only 0.3 ~ 0.4nm, and diffusion way is two-dimensional layer
Between spread, therefore, high rate performance is difficult to improve, and substantially all within 10C multiplying power, meets 10C multiplying power or more to develop
Lithium ion battery negative material, it is necessary to non-graphite negative electrode material is selected, wherein with soft carbon, hard carbon, lithium titanate three classes material
Most study.
Lithium titanate material is spinelle configuration, space group Fd3m, can three-dimensional embedding de- lithium, lithium ion diffusion coefficient compares graphite
High two orders of magnitude, can satisfy 30C rate charge-discharge, however, the material energy densities are lower, specific capacity is only 160 ~
175mAh/g, electric conductivity is poor, and cost is also higher, therefore application field is very limited.The spy of soft carbon negative electrode material and lithium titanate
Point is all to belong to that high rate performance is good than more consistent, but the material that energy density is relatively low.
In contrast, hard carbon material exactly not only has good high rate performance but also energy density with higher, is a
The best negative electrode material of development prospect.However, this kind of material specific surface area is higher (to be greater than >=10 m2/ g), easily absorb moisture simultaneously
Side reaction occurs, coulombic efficiency is generally lower for the first time.
Summary of the invention
The present invention is intended to provide a kind of power lithium-ion battery hard carbon cathode material and preparation method thereof.
The present invention is achieved by the following technical programs:
A kind of preparation method of power lithium-ion battery hard carbon cathode material, which is characterized in that it the following steps are included:
(I) stock up: getting organic polymer raw material ready, the organic polymer raw material be phenolic resin, furfural resin,
One or more of epoxy resin, glucose, sucrose, cyclodextrin, starch, butadiene-styrene rubber；
(II) the above-mentioned organic polymer raw material got ready coarse crushing: are machined to granularity less than 100 purposes by broken
Particle；
(III) the pre-heat treatment: the particle after coarse crushing is put into the pushed bat kiln filled with nitrogen protection and is preheated；
(IV) fine crushing, classification: the material after the pre-heat treatment is subjected to fine crushing and classification on three-level joint crusher, is obtained
2# material is as spare material, and 1# material can continue to return throwing, and 3# makees waste powder treating, the 2# material particles size control after classification fine crushing
System exists: D10 >=5 μm, D50 is between 10 ~ 12 μm, D90≤25 μm, DMAX≤35 μm；
(V) it coats, be carbonized: the 2# material after above-mentioned classification fine crushing being subjected to the processing of surface cladding, covering is coal drip
Blueness, softening point >=220 DEG C, surface covering amount are 1 ~ 4%, and the material after cladding is then carried out carbonization treatment under nitrogen protection.
Preferably, the heating rate in the step (III) when preheating is controlled in 1 ~ 10 DEG C/min, the maximum temperature of preheating
At 300 ~ 700 DEG C, the soaking time of maximum temperature is 60min for control.
Preferably, carburizing temperature is 1600 DEG C in the step (V), and carbonization heating rate is 2 DEG C/min, soaking time
2h。
Preferably, when the step (I) is stocked up, first by organic polymer raw material and carbon nanotube according to weight ratio
It is mixed for 100:1, mixed material is then put into immersion 3-5 h in acetum, then cleaned with deionized water, it will
Mixed material after cleaning is as the stock before coarse crushing.
A kind of power lithium-ion battery hard carbon cathode material, which is characterized in that it is made of above-mentioned preparation method
Hard carbon cathode material.
Preferably, the hard carbon cathode material: D50 is between 10 ~ 12 μm, SSA≤2.5m2/ g, TD >=0.9g/cc.
Technical effect of the invention is as follows:
Macromolecule organic during heat treatment, can inevitably generate increased number of stomata, cause material specific surface area higher, this
Invention generates these pore structures by way of the pre-heat treatment of macromolecule coarse particles in advance, then carry out again it is fine crushing, by these
Gap destroys, and by cladding, charing process, the specific surface area of hard carbon material is controlled in 2.5m2Within/g.
The lithium ion battery cathode material made of the method for the present invention, the material reversible capacity are higher than 500mAh/
G, pole piece are compacted up to 1.55g/cc, and first charge discharge efficiency is more than 2000 weeks higher than 80%, the 5C charge-discharge cycle service life, conventional batteries system
Under, 30C charging capacity is that 85% or more, the 30C discharge capacity of 1C charging capacity is 90% or more 1C discharge capacity.
Specific embodiment
Embodiment 1
A kind of preparation method of power lithium-ion battery hard carbon cathode material, the specific steps are as follows:
(I) phenolic resin is carried out to the granularity of coarse crushing to -100 mesh；
(II) the pre-heat treatment is in N2Carried out in the pushed bat kiln of protection, heating rate of the material in pushed bat kiln be essentially 3 DEG C/
Min, maximum temperature are 700 DEG C, keep the temperature 60min；
(III) fine crushing, classification: the material of the pre-heat treatment is carried out to fine crushing and classification on three-line machine, collecting 2# material is institute
Need material, 1# material can continue to return throwing, and 3# makees waste powder treating, after classification guarantee 2# material D10 >=5 μm, D50 between 10 ~ 12 μm,
D90≤25 μm, DMAX≤35 μm；
(IV) surface covering amount is 1%, 1600 DEG C, N2It is carbonized under atmosphere, the coal tar pitch that covering is 220 DEG C of softening point, charcoal
Change heating rate is 2 DEG C/min, and soaking time 2h is to get the power lithium-ion battery hard carbon cathode material required to the present invention
Material.
Embodiment 2
A kind of preparation method of power lithium-ion battery hard carbon cathode material, the specific steps are as follows:
(I) starch is carried out to the granularity of coarse crushing to -100 mesh；
(II) the pre-heat treatment is in N2Carried out in the pushed bat kiln of protection, heating rate of the material in pushed bat kiln be essentially 5 DEG C/
Min, maximum temperature are 300 DEG C, keep the temperature 60min；
(III) fine crushing, classification: the material of the pre-heat treatment is carried out to fine crushing and classification on three-line machine, collecting 2# material is institute
Need material, 1# material can continue to return throwing, and 3# makees waste powder treating, after classification guarantee 2# material D10 >=5 μm, D50 between 10 ~ 12 μm,
D90≤25 μm, DMAX≤35 μm；
(IV) surface covering amount is 3%, 1600 DEG C, N2It is carbonized under atmosphere, the coal tar pitch that covering is 250 DEG C of softening point, charcoal
Change heating rate is 2 DEG C/min, soaking time 2h.
Embodiment 3
A kind of preparation method of power lithium-ion battery hard carbon cathode material, the specific steps are as follows:
(I) butadiene-styrene rubber is carried out to the granularity of coarse crushing to -100 mesh；
(II) the pre-heat treatment is in N2Carried out in the pushed bat kiln of protection, heating rate of the material in pushed bat kiln be essentially 1 DEG C/
Min, maximum temperature are 500 DEG C, keep the temperature 60min；
(III) fine crushing, classification: the material of the pre-heat treatment is carried out to fine crushing and classification on three-line machine, collecting 2# material is institute
Need material, 1# material can continue to return throwing, and 3# makees waste powder treating, after classification guarantee 2# material D10 >=5 μm, D50 between 10 ~ 12 μm,
D90≤25 μm, DMAX≤35 μm；
(IV) surface covering amount is 2%, 1600 DEG C, N2It is carbonized under atmosphere, the coal tar pitch that covering is 250 DEG C of softening point, charcoal
Change heating rate is 2 DEG C/min, soaking time 2h.
Embodiment 4
A kind of preparation method of power lithium-ion battery hard carbon cathode material, the specific steps are as follows:
(I) first phenolic resin is mixed with carbon nanotube according to weight ratio for 100:1, is then put into mixed material
3-5 h is impregnated in acetum, the concentration of acetum is preferably 30-50%, then is cleaned with deionized water, after cleaning
Mixed material as the stock before coarse crushing.
(II) mixed material after above-mentioned cleaning is passed through into jaw crusher coarse crushing to less than the granularity of 100 mesh；
(III) the pre-heat treatment: in N2It is carried out in the pushed bat kiln of protection, heating rate of the material in pushed bat kiln is essentially 3
DEG C/min, maximum temperature is 700 DEG C, keeps the temperature 60min；
(IV) fine crushing, classification: the material of the pre-heat treatment is carried out to fine crushing and classification on three-line machine, collecting 2# material is institute
Need material, 1# material can continue to return throwing, and 3# makees waste powder treating, after classification guarantee 2# material D10 >=5 μm, D50 between 10 ~ 12 μm,
D90≤25 μm, DMAX≤35 μm；
(V) surface covering amount is 1%, 1600 DEG C, N2It is carbonized under atmosphere, the coal tar pitch that covering is 220 DEG C of softening point, charcoal
Change heating rate is 2 DEG C/min, soaking time 2h.
Comparative example
A kind of preparation method of power lithium-ion battery hard carbon cathode material, first by phenolic resin block direct carbonization,
Then broken classification is carried out according to Granularity Distribution described in this patent.
Test result is as follows for the various embodiments described above and comparative example shown in table:
Analysis: it is found that product of the present invention, specific surface area and first effect are substantially better than comparative example for comparison from table,
Its chemical property is also slightly better than comparative example.
Claims (4)
1. a kind of preparation method of power lithium-ion battery hard carbon cathode material, which is characterized in that it the following steps are included:
(I) stock up: getting organic material ready, the organic material be phenolic resin, furfural resin, epoxy resin, glucose,
One or more of sucrose, cyclodextrin, starch, butadiene-styrene rubber；
(II) the above-mentioned organic material got ready coarse crushing: is machined to particle of the granularity less than 100 mesh by broken；
(III) the pre-heat treatment: the particle after coarse crushing being put into the pushed bat kiln filled with nitrogen protection and is preheated, liter when preheating
In 1 ~ 10 DEG C/min, the maximum temperature control of preheating is warm speed control in 300 ~ 700 DEG C, the soaking time of maximum temperature
60min;
(IV) fine crushing, classification: the material after the pre-heat treatment is subjected to fine crushing and classification on three-level joint crusher, obtains 2# object
Material is used as spare material, and 1# material can continue to return throwing, and 3# makees waste powder treating, the 2# material particles size control after classification fine crushing
In D10 >=5 μm, D50 is between 10 ~ 12 μm, D90≤25 μm, DMAX≤35 μm；
(V) it coats, be carbonized: the 2# material after above-mentioned classification fine crushing being subjected to the processing of surface cladding, covering is coal tar pitch, soft
Change point >=220 DEG C, surface covering amount is 1 ~ 4%, then the material after cladding is carried out carbonization treatment under nitrogen protection, is carbonized
Temperature is 1600 DEG C, and carbonization heating rate is 2 DEG C/min, soaking time 2h.
2. a kind of preparation method of power lithium-ion battery hard carbon cathode material according to claim 1, feature exist
In being first that 100:1 is mixed according to weight ratio by organic material and carbon nanotube, so when the step (I) is stocked up
Mixed material is put into immersion 3-5 h in acetum afterwards, then is cleaned with deionized water, the mixed material after cleaning is made
For the stock before coarse crushing.
3. a kind of power lithium-ion battery hard carbon cathode material, it is characterised in that: it is using of any of claims 1 or 2
A kind of hard carbon cathode material of the preparation method production of power lithium-ion battery hard carbon cathode material.
4. a kind of power lithium-ion battery hard carbon cathode material according to claim 3, it is characterised in that: the hard carbon
Negative electrode material: D50 is between 10 ~ 12 μm, SSA≤2.5m2/ g, TD >=0.9g/cc, as lithium ion battery cathode material,
The material reversible capacity is higher than 500mAh/g, and pole piece is compacted up to 1.55g/cc, and first charge discharge efficiency is higher than 80%, the 5C charge-discharge cycle longevity
Life was more than 2000 weeks, and under conventional batteries system, 30C charging capacity is that 85% or more, the 30C discharge capacity of 1C charging capacity is 1C
90% or more discharge capacity.
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| CN107959006B (en) * | 2017-10-31 | 2020-02-18 | 华南理工大学 | Lignin-based hard carbon/carbon nanotube composite material, preparation method thereof and application thereof in lithium ion battery cathode material |
| CN108682858A (en) * | 2018-06-08 | 2018-10-19 | 遇秉武 | A kind of preparation method of negative electrode of lithium ion battery hard carbon material |
| CN109244385A (en) * | 2018-08-15 | 2019-01-18 | 深圳市大家帮科技有限公司 | A kind of lithium ion battery hard carbon cathode material and preparation method thereof |
| CN114824257A (en) * | 2022-04-26 | 2022-07-29 | 湖南镕锂新材料科技有限公司 | Hard carbon negative electrode material and preparation method and application thereof |
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| JP2014172816A (en) * | 2013-03-13 | 2014-09-22 | Ken Masunaga | Method for producing carbon material, carbon material, and secondary battery |
| WO2014157503A1 (en) * | 2013-03-29 | 2014-10-02 | 日本電気株式会社 | Negative electrode carbon material for lithium secondary battery, negative electrode for lithium secondary battery, and lithium secondary battery |
| JP2014199746A (en) * | 2013-03-29 | 2014-10-23 | 日本電気株式会社 | Negative electrode carbon material for lithium secondary battery, negative electrode for lithium battery, and lithium secondary battery |
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| CN103311518A (en) * | 2012-03-07 | 2013-09-18 | 宁波杉杉新材料科技有限公司 | Hard-carbon negative electrode material for lithium ion secondary battery and preparation method thereof |
| CN102881869A (en) * | 2012-09-26 | 2013-01-16 | 东莞市翔丰华电池材料有限公司 | Modified hard carbon negative electrode material for lithium ion battery and preparation method for modified hard carbon negative electrode material |
| JP2014172816A (en) * | 2013-03-13 | 2014-09-22 | Ken Masunaga | Method for producing carbon material, carbon material, and secondary battery |
| WO2014157503A1 (en) * | 2013-03-29 | 2014-10-02 | 日本電気株式会社 | Negative electrode carbon material for lithium secondary battery, negative electrode for lithium secondary battery, and lithium secondary battery |
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