CN108682821A - A kind of preparation method of lithium ion battery cobalt-based metal oxide composite electrode - Google Patents
A kind of preparation method of lithium ion battery cobalt-based metal oxide composite electrode Download PDFInfo
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- CN108682821A CN108682821A CN201810516906.7A CN201810516906A CN108682821A CN 108682821 A CN108682821 A CN 108682821A CN 201810516906 A CN201810516906 A CN 201810516906A CN 108682821 A CN108682821 A CN 108682821A
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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
- H01M4/362—Composites
- H01M4/366—Composites as layered products
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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
- H01M4/48—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides
- H01M4/52—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides of nickel, cobalt or iron
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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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- 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 present invention relates to a kind of lithium ion battery preparation method of cobalt-based metal oxide composite electrode, the electrode material is then prepared through two step high-temperature heat treatments using cobalt-based metal organic framework compound as presoma；The electrode material has the various structures advantages such as graduation hole, N doping, extra granular size.The preparation method that the present invention uses is simple and effective, prepared combination electrode material shows excellent storage lithium performance, the presence of the graduate pore structure of material internal and carbon nanotube can keep the structural stability of electrode well, and more multichannel is provided for lithium ion transport, to ensure that the lithium ion battery using the material preparation still has excellent cyclical stability at higher current densities.
Description
Technical field
The present invention relates to the cobalt based metal oxides that a kind of nitrogen-doped carbon can be used for lithium ion battery and carbon nanotube coat
Object combination electrode material and preparation method thereof.
Technical background
Lithium ion battery has many advantages, such as that energy density is high, has a safety feature, memory-less effect, be widely used with it is all kinds of
In portable electronic device.However, in order to promote the growth requirement of electric vehicle and large scale electric network equipment, people are to lithium ion
More stringent requirements are proposed for the high rate performance and stored energy capacitance of battery.When traditional graphite material is as negative electrode of lithium ion battery,
Its theoretical lithium storage content is only 372mAh/g, it is difficult to meet actual demand, therefore is developed with higher capacity, more excellent high rate performance
New electrode materials be just particularly important.Transition metal oxide with higher theoretical lithium storage content has just obtained extensively
Concern, wherein CoC3OC4Theoretical lithium storage content be up to (890mAh/g), be it is a kind of relatively have future negative electrode of lithium ion battery material
Material, still, CoC3OC4The insertion of lithium ion abjection during can occur larger volume change, and then dusting, fall off, make
At the irreversible decaying of capacity；In addition CoC3OC4Electric conductivity it is poor, cause its high rate performance undesirable.
It is the effective ways for improving material electrochemical performance that the particle size of electrode material, which is reduced to Nano grade,.Nanometer
Grade electrode material usually has higher specific surface area and more reactivity sites, while nano level electrode material can also
The stress generated in volume expansion is effectively relieved, shortens electrons/ions transmission range, to keeping the structural stability of material and carrying
High electrode high rate performance plays good effect.Nano material and carbon base body are subjected to the conduction that recombination energy further increases material
Property, transition metal oxide/carbon composite electrode of various structures is had reported at present.However traditional transition metal oxide/
Carbon composite, particles' interaction is poor, although electrons/ions transmission speed in single nano material enhances,
Transmission rate between nano material is still undesirable.It up to the present, can be there are no a kind of cobalt-based metal oxide electrode material
Higher current density (>Realize that high power capacity conservation rate and long circulation life, problem above limit lithium ion battery under 10A/g)
Application surface hinders the more preferable development of lithium ion battery industry.
The excellent carbon nanotube of electric conductivity is introduced in cobalt-based metal oxide/carbon composite, prepares cobalt-based metal
Oxide/carbon/carbon nanotube composite mesh structure, between the ion/electron transfer rate and strengthening material improving nanometer materials
Material structural stability plays an important role.In addition, the introducing of hetero atom nitrogen can also enhance wetting capacity of the electrolyte to electrode material.
The method that tradition prepares cobalt-based metal oxide/nitrogen-doped carbon/carbon nano tube compound material is generally required carbon with physical method
Nanotube and target product progress are compound, or need to introduce additional carbon source or nitrogen source, and preparation method is complicated, and transition in product
Metal oxide and carbon base body intermolecular forces are poor, can not ensure that electrode material still has at higher current densities and preferably follow
Ring stability.Based on the above analysis, the present invention proposes a kind of nanoscale still at higher current densities with long circulation life
Cobalt metal oxide/nitrogen-doped carbon/carbon nano-tube combination electrode and preparation method thereof.
Invention content
The present invention in order to realize lithium ion battery at higher current densities still have higher capacity retention ratio and cycle the longevity
Life, it is proposed that it is a kind of using cobalt-based metal organic framework compound be presoma, preparation have both graduation pore structure, N doping and
The electrode structure and preparation method thereof of cobalt-based metal oxide/nitrogen-doped carbon/carbon nano tube compound material of nano effect.The party
Method simple possible, is easy to large-scale production at stable structure.
The technical solution adopted by the present invention is to prepare cobalt-based metal organic framework compound first with coprecipitation, so
The cobalt-based metal organic framework compound of preparation is subjected to high temperature cabonization afterwards, then to product under acetylene/argon gas mixed gas
Secondary heat treatment is carried out, target product is obtained after fully oxidized.It is as follows：
(1) cobalt salt, 2-methylimidazole are dispersed in water, stirring or ultrasound are allowed to be uniformly dispersed；Subsequent static ageing
12h is then centrifuged for separation, drying obtains dried powder；
(2) powder is subjected to high-temperature heat treatment under an argon atmosphere；
(3) the above-mentioned powder for preparing under acetylene/argon gas mixed gas is subjected to secondary high-temperature processing, product is collected after cooling
Carry out subsequent processing；
(4) will after secondary high-temperature is handled powder, be transferred to air atmosphere and aoxidized at low temperature.
Cobalt salt described in step (1) is CoC (NOC3)2·6H2OC、CoCCl2·6H2OC or CoC (CH3COCOC)2·
6H2Any one or more in OC
The molar ratio of 2-methylimidazole and cobalt salt described in step (1) is 10:1~70:1, best proportion 39:1；
Calcination temperature described in step (2) is 500~950 DEG C；
Heat treatment time described in step (2) is 1-4h；
Heating rate described in step (2) is 1 DEG C/min~10 DEG C/min, and optimal heating rate is 3 DEG C/min；
Acetylene content is 10~30% volume ratios in acetylene/argon gas mixed gas described in step (3)；
Secondary heat treatment temperature described in step (3) is 350~700 DEG C of C/min, and processing time is 5~60min, most preferably
Processing time is 20min；
Heating rate described in step (3) is 1 DEG C/min~10 DEG C/min, and optimal heating rate is 5 DEG C/min；
Oxidization time described in step (4) is 10~48h, and oxidizing temperature is 100~200 DEG C, optimum reaction condition 200
It is reacted for 24 hours at DEG C；
The present invention obtains cobalt-based metal oxygen using cobalt-based metal organic framework compound as presoma after substep high-temperature process
Compound/nitrogen-doped carbon/carbon nano-tube combination electrode, preparation method is simple, and without introducing additional carbon source or nitrogen source, product
In generated in-situ nitrogen-doped carbon/carbon nanotube conducting matrix and cobalt-based metal oxide combine closely, can guarantee electrode material
In multiple charge and discharge process still with higher reactivity and the structure stablized.
Description of the drawings
Fig. 1 is cobalt-based metal oxide/nitrogen-doped carbon/carbon nano tube compound material prepared in the embodiment of the present invention 1
SEM figure.
Fig. 2 is cobalt-based metal oxide/nitrogen-doped carbon/carbon nano tube compound material prepared in the embodiment of the present invention 1
TEM figure.
Fig. 3 is cobalt-based metal oxide/nitrogen-doped carbon/carbon nano tube compound material prepared in the embodiment of the present invention 3
Cycle performance figure of the lithium ion battery of preparation under 15A/g electric currents.
Specific implementation mode：
Embodiment 1：
The cobalt salt of selection is CoC (NOC3)2·6H2OC, the molar ratio for controlling 2-methylimidazole and cobalt salt is 30:1, it stirs
Static hatching 12h after 10min is mixed, product centrifuges, is dry.Powder is transferred in tube furnace after drying, argon gas protection lower 5
DEG C/min is warming up to 550 DEG C and keeps the temperature 2h, after cooled to room temperature, carry out secondary high-temperature heat treatment.Acetylene volume is selected to contain
Acetylene/argon gas mixed gas that amount is 10%, 5 DEG C/min are warming up to 550 DEG C, keep the temperature 10min, collection of products.By above-mentioned powder
It is placed under 200 DEG C of air atmosphere and aoxidizes for 24 hours, obtain final product.
SEM and the TEM figure such as Fig. 1, Fig. 2 institutes for cobalt-based metal oxide/nitrogen-doped carbon/carbon nanotube that the present embodiment obtains
Show.
Embodiment 2：
The cobalt salt of selection is CoC (Cl)2·6H2OC, the molar ratio for controlling 2-methylimidazole and cobalt salt is 60:1, stirring
Static hatching 12h after 10min, product centrifuge, are dry.Powder is transferred in tube furnace after drying, and lower 5 DEG C of argon gas protection/
Min is warming up to 600 DEG C and keeps the temperature 3h, after cooled to room temperature, carries out secondary high-temperature heat treatment.Select acetylene volume content be
20% acetylene/argon gas mixed gas, 3 DEG C/min are warming up to 500 DEG C, keep the temperature 15min, collection of products.Above-mentioned powder is placed in
36h is aoxidized under 150 DEG C of air atmosphere, obtains final product.
Embodiment 3：
The cobalt salt of selection is CoC (NOC3)2·6H2OC, the molar ratio for controlling 2-methylimidazole and cobalt salt is 39:1, it stirs
Static hatching 12h after 10min is mixed, product centrifuges, is dry.Powder is transferred in tube furnace after drying, argon gas protection lower 3
DEG C/min is warming up to 600 DEG C and keeps the temperature 2h, after cooled to room temperature, carry out secondary high-temperature heat treatment.Acetylene volume is selected to contain
Acetylene/argon gas mixed gas that amount is 15%, 5 DEG C/min are warming up to 600 DEG C, keep the temperature 10min, collection of products.By above-mentioned powder
It is placed under 200 DEG C of air atmosphere and aoxidizes 48h, obtain final product.
Product cycle performance test under the current density of 15A/g is as shown in Figure 3
Embodiment 4：
The cobalt salt of selection is CoC (CH3COCOC)2·6H2OC, the molar ratio for controlling 2-methylimidazole and cobalt salt is 70:
1, static hatching 12h after 10min is stirred, product centrifuges, is dry.Powder is transferred in tube furnace after drying, argon gas protection
Lower 10 DEG C/min is warming up to 700 DEG C and keeps the temperature 4h, after cooled to room temperature, carries out secondary high-temperature heat treatment.Select acetylene body
Acetylene/argon gas mixed gas that product content is 30%, 1 DEG C/min are warming up to 700 DEG C, keep the temperature 10min, collection of products.It will be above-mentioned
Powder is placed under 250 DEG C of air atmosphere and aoxidizes 36h, obtains final product.
As can be seen from Figure 1 it is graduate polyhedral structure that this method, which prepares product, and polyhedron is by nano-scale particle
Second Aggregation forms, while many generated in-situ carbon nanotube networks of sample surfaces homoepitaxial.TEM is further confirmed
Product division center prepared by this method is CoC3OC4, outer layer coated nitrogen-doped carbon base carbon nanotube successively.It can be seen in Fig. 3
Going out to prepare product has excellent storage lithium performance, still has higher capacity to protect after 5000 weeks under the high current density of 15A/g
Holdup and the cycle life stablized.
Claims (10)
1. a kind of lithium ion battery preparation method of cobalt-based metal oxide composite electrode comprising following steps：
(1) cobalt salt, 2-methylimidazole are dispersed in water, stirring or ultrasound are allowed to be uniformly dispersed；Subsequent static ageing 12h, so
It centrifuges afterwards, drying obtains dried powder；
(2) powder is subjected to high-temperature heat treatment under an argon atmosphere；
(3) the above-mentioned powder for preparing is subjected to secondary high-temperature processing under acetylene/argon gas mixed gas, collecting product after cooling carries out
Subsequent processing；
(4) will after secondary high-temperature is handled powder, be transferred to air atmosphere and aoxidized at low temperature.
2. preparation method according to claim 1, it is characterised in that：Cobalt salt described in the step (1) is CoC
(NOC3)2·6H2OC、CoCCl2·6H2OC or CoC (CH3COCOC)2·6H2Any one or more in OC.
3. preparation method according to claim 1, it is characterised in that：2-methylimidazole described in step (1) and cobalt salt
Molar ratio is 10:1~70:1..
4. preparation method according to claim 1, it is characterised in that：Calcination temperature described in step (2) is 500~950
℃。
5. preparation method according to claim 1, it is characterised in that：Heat treatment time described in step (2) is 1-4h.
6. preparation method according to claim 1, it is characterised in that：Heating rate described in step (2) be 1 DEG C/min~
10℃/min。
7. preparation method according to claim 1, it is characterised in that：In acetylene/argon gas mixed gas described in step (3)
Acetylene content is 10~30% volume ratios.
8. preparation method according to claim 1, it is characterised in that：Secondary heat treatment temperature described in step (3) is 350
~700 DEG C/min, processing time is 5~60min, and the optimization process time is 20min.
9. preparation method according to claim 1, it is characterised in that：Heating rate described in step (3) be 1 DEG C/min~
10 DEG C/min, optimal heating rate is 5 DEG C/min.
10. preparation method according to claim 1, it is characterised in that：Oxidization time described in step (4) is 10~48h,
Oxidizing temperature is 100~200 DEG C, and optimum reaction condition is to be reacted for 24 hours under 200 DEG C of C.
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111463406A (en) * | 2020-04-09 | 2020-07-28 | 江苏师范大学 | Preparation method of cobalt-doped zinc-based metal selenide composite electrode for lithium ion battery |
| CN112098486A (en) * | 2020-09-18 | 2020-12-18 | 湖北中烟工业有限责任公司 | N, P co-doped nano carbon-based framework material modified electrode and preparation method and application thereof |
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| CN104681810A (en) * | 2015-01-11 | 2015-06-03 | 北京工业大学 | Cobaltosic oxide nitrogen-doped carbon nanotube three-dimensional composite electrode material for lithium ion battery and manufacturing method of electrode material |
| CN106082167A (en) * | 2016-06-13 | 2016-11-09 | 西南大学 | The carbon nano tube compound material of porous carbon supporting base end portion coated metal granule and the preparation method of derivant, product and application |
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2018
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Patent Citations (3)
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| CN106082167A (en) * | 2016-06-13 | 2016-11-09 | 西南大学 | The carbon nano tube compound material of porous carbon supporting base end portion coated metal granule and the preparation method of derivant, product and application |
| CN106229541A (en) * | 2016-07-27 | 2016-12-14 | 安徽师范大学 | A kind of N C/Co3o4hollow ball shaped nanometer material and its preparation method and application |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111463406A (en) * | 2020-04-09 | 2020-07-28 | 江苏师范大学 | Preparation method of cobalt-doped zinc-based metal selenide composite electrode for lithium ion battery |
| CN111463406B (en) * | 2020-04-09 | 2022-03-25 | 江苏师范大学 | Preparation method of cobalt-doped zinc-based metal selenide composite electrode for lithium ion battery |
| CN112098486A (en) * | 2020-09-18 | 2020-12-18 | 湖北中烟工业有限责任公司 | N, P co-doped nano carbon-based framework material modified electrode and preparation method and application thereof |
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