CN108682832A - Lithium battery composite negative pole material and preparation method thereof - Google Patents
Lithium battery composite negative pole material and preparation method thereof Download PDFInfo
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- CN108682832A CN108682832A CN201810594371.5A CN201810594371A CN108682832A CN 108682832 A CN108682832 A CN 108682832A CN 201810594371 A CN201810594371 A CN 201810594371A CN 108682832 A CN108682832 A CN 108682832A
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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
- H01M4/364—Composites as mixtures
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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
- H01M4/485—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides of mixed oxides or hydroxides for inserting or intercalating light metals, e.g. LiTi2O4 or LiTi2OxFy
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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
- H01M4/50—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides of manganese
- H01M4/505—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides of manganese of mixed oxides or hydroxides containing manganese for inserting or intercalating light metals, e.g. LiMn2O4 or LiMn2OxFy
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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
- H01M4/525—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides of nickel, cobalt or iron of mixed oxides or hydroxides containing iron, cobalt or nickel for inserting or intercalating light metals, e.g. LiNiO2, LiCoO2 or LiCoOxFy
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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 discloses a kind of lithium battery composite negative pole material, including the internal complex microsphere with gap structure, the complex microsphere is lithium titanate and nano-silicon forms complex microsphere, and the grain size of the nano-silicon is 40~60nm.And the preparation method of lithium battery composite negative pole material is disclosed, the application effectively increases electric conductivity, especially suitable for the large-scale and higher household electrical appliances of utilization rate.
Description
Technical field
The present invention relates to lithium battery material fields, and in particular to a kind of lithium battery composite negative pole material and its preparation side
Method.
Background technology
It by lithium metal or lithium alloy is negative material, using the battery of non-aqueous electrolytic solution that lithium battery, which is a kind of,.1912
Year lithium metal battery is proposed and is studied by Gilbert N.Lewis earliest.When the 1970s, M.S.Whittingham is carried
Go out and the lithium ion battery that begins one's study.Since the chemical characteristic of lithium metal is very active so that the processing of lithium metal preserves, makes
With very high to environmental requirement.So lithium battery is not applied for a long time.With the development of science and technology, present lithium battery
Have become mainstream.
It is most of currently on the market to use negative material of the lithium titanate as lithium battery, but the intrinsic conductivity of lithium carbonate
It is relatively low, only 10-9S/cm, belongs to insulator, poorly conductive, poor and specific capacity declines so as to cause performance when high power charging-discharging
Subtract comparatively fast, heavy-current discharge performance is undesirable.
Invention content
To solve the above-mentioned problems, a kind of lithium battery composite negative pole material of present invention offer and preparation method thereof, effectively
Electric conductivity is improved, especially suitable for the large-scale and higher household electrical appliances of utilization rate.
To achieve the goals above, the present invention uses following technical scheme：A kind of lithium battery composite negative pole material, including
Inside has the complex microsphere of gap structure, and the complex microsphere is lithium titanate and nano-silicon forms complex microsphere, described
The grain size of nano-silicon is 40~60nm.
Further, the lithium titanate is the lithium titanate for adulterating manganese and cobalt.
Further, a kind of preparation method of lithium battery composite negative pole material, includes the following steps：
1) manganese carbonate, lithium titanate, cobalt oxide are uniformly mixed according to a certain percentage, are put into stirring ball mill and carry out machinery
300 mesh sieve is crossed in activation after dry；
2) nano-silicon, agraphitic carbon, N- methyl pyrrole network alkanones are matched according to a certain percentage, ultrasonic wave dispersion 20min is stirred
It mixes uniformly, the product after step 1) is sieved is uniformly mixed with nano-silicon solution, is placed in roller furnace calcines 4 under nitrogen protection
~6h, calcination temperature are 600~700 DEG C, Temperature fall；
3) powder after Temperature fall is put into ball mill ball milling, is again placed in roller furnace after the completion of ball milling, in nitrogen
2~4h is calcined under protection, calcination temperature is 1000~1500 DEG C, and natural cooling obtains negative material after removing magnetic screening.
Further, the molar ratio of element is Mn in the step 1):Li：Co=1.6:0.621：0.2.
Further, in step 2), in terms of mass parts, the nano-silicon is 20~40 parts, agraphitic carbon 80~100
Part, 200~220 parts of N- methyl pyrrole networks alkanone.
Negative material made from this law is with adhesive MSi, super conductive black, sodium carboxymethylcellulose according to 80:2:
1.5:1 ratio is dissolved in water to form slurry, and the slurry is coated on copper foil and is fabricated to negative plate.
Compared with prior art, what the present invention was brought has the beneficial effect that：By the present invention in that with doping metals example manganese and
The lithium titanate of cobalt replaces part cobalt, the cost of material of manganese to be significantly less than cobalt, reduce production cost, while changing significantly using manganese
It has been apt to the conductivity of lithium titanate, nano-silicon is added, there is space inside nano-silicon, be full of when being expanded convenient for silicon, and nano-silicon subtracts
The small volume of silicon, is conducive to the cycle performance of battery, particularly suitable for the white goods used repeatedly.
And then the present invention is calcined by multiple ball milling by first activating doped lithium titanate, promoted battery high temperature resistant and
Explosion-proof performance, negative material made from this law, can effectively prevent lithium titanate in charge and discharge process and reacts with electrolyte, to
The chemical property of battery is improved, specific capacity is more than 250mAh/g after recycling 80 times, and capacity is protected after being recycled 150 times in 10C multiplying powers
Holdup ＞ 97%.
Specific implementation mode
With reference to specific embodiment, the present invention is described in detail.
Embodiment 1
1) it is Mn according to the molar ratio of element by manganese carbonate, lithium titanate, cobalt oxide:Li：Co=1.6:0.621：0.2 mixing
Uniformly, it is put into stirring ball mill and carries out mechanical activation, 300 mesh sieve is crossed after dry；
2) in terms of mass parts, by 20 parts of nano-silicon, 80 parts of agraphitic carbon, 200 parts of N- methyl pyrrole networks alkanone, ultrasonic wave dispersion
20min is stirred evenly, and the product after step 1) is sieved is uniformly mixed with nano-silicon solution, is placed in roller furnace under nitrogen protection
Middle calcining 4h, calcination temperature are 600 DEG C, Temperature fall；
3) powder after Temperature fall is put into ball mill ball milling, is again placed in roller furnace after the completion of ball milling, in nitrogen
2h is calcined under protection, calcination temperature is 1000 DEG C, and natural cooling obtains negative material after removing magnetic screening.
Specific nature is shown in Table 1.
Embodiment 2
1) it is Mn according to the molar ratio of element by manganese carbonate, lithium titanate, cobalt oxide:Li：Co=1.6:0.621：0.2 mixing
Uniformly, it is put into stirring ball mill and carries out mechanical activation, 300 mesh sieve is crossed after dry；
2) in terms of mass parts, by 30 parts of nano-silicon, 90 parts of agraphitic carbon, 210 parts of N- methyl pyrrole networks alkanone, ultrasonic wave dispersion
20min is stirred evenly, and the product after step 1) is sieved is uniformly mixed with nano-silicon solution, is placed in roller furnace under nitrogen protection
Middle calcining 5h, calcination temperature are 650 DEG C, Temperature fall；
3) powder after Temperature fall is put into ball mill ball milling, is again placed in roller furnace after the completion of ball milling, in nitrogen
3h is calcined under protection, calcination temperature is 1250 DEG C, and natural cooling obtains negative material after removing magnetic screening.
Specific nature is shown in Table 1.
Embodiment 3
1) it is Mn according to the molar ratio of element by manganese carbonate, lithium titanate, cobalt oxide:Li：Co=1.6:0.621：0.2 mixing
Uniformly, it is put into stirring ball mill and carries out mechanical activation, 300 mesh sieve is crossed after dry；
2) in terms of mass parts, by 40 parts of nano-silicon, 100 parts of agraphitic carbon, 220 parts of N- methyl pyrrole networks alkanone, ultrasonic wavelength-division
Scattered 20min is stirred evenly, and the product after step 1) is sieved is uniformly mixed with nano-silicon solution, is placed in roller-way under nitrogen protection
6h is calcined in stove, calcination temperature is 700 DEG C, Temperature fall；
3) powder after Temperature fall is put into ball mill ball milling, is again placed in roller furnace after the completion of ball milling, in nitrogen
4h is calcined under protection, calcination temperature is 1300 DEG C, and natural cooling obtains negative material after removing magnetic screening.
Specific nature is shown in Table 1.
Reference examples
1) it is Mn according to the molar ratio of element by manganese carbonate, lithium titanate, cobalt oxide:Li：Co=1.6:0.621：0.2 mixing
Uniformly, it is put into stirring ball mill and carries out mechanical activation, 300 mesh sieve is crossed after dry；
2) in terms of mass parts, by 40 parts of nano-silicon, 100 parts of agraphitic carbon, 220 parts of N- methyl pyrrole networks alkanone, ultrasonic wavelength-division
Scattered 20min is stirred evenly, and the product after step 1) is sieved is uniformly mixed with nano-silicon solution, is placed in roller-way under nitrogen protection
6h is calcined in stove, calcination temperature is 700 DEG C, Temperature fall；
3) powder after Temperature fall is put into ball mill ball milling, is again placed in roller furnace after the completion of ball milling, in nitrogen
4h is calcined under protection, calcination temperature is 1300 DEG C, and natural cooling obtains negative material after removing magnetic screening.
Specific nature is shown in Table 1.
Table 1
The basic principles and main features and the features of the present invention of the present invention have been shown and described above.The technology of the industry
Personnel are it should be appreciated that the present invention is not limited to the above embodiments, and the above embodiments and description only describe this
The principle of invention, without departing from the spirit and scope of the present invention, various changes and improvements may be made to the invention, these changes
Change and improvement is both fallen in the range of claimed invention.The scope of protection of present invention is by appended claims
And its equivalent thereof.
Claims (5)
1. a kind of lithium battery composite negative pole material, it is characterised in that：It is described including the internal complex microsphere with gap structure
Complex microsphere be that lithium titanate and nano-silicon form complex microsphere, the grain size of the nano-silicon is 40~60nm.
2. lithium battery composite negative pole material according to claim 1, it is characterised in that：The lithium titanate is doping manganese
With the lithium titanate of cobalt.
3. a kind of preparation method of lithium battery composite negative pole material, it is characterised in that：Include the following steps：
1) manganese carbonate, lithium titanate, cobalt oxide are uniformly mixed according to a certain percentage, are put into stirring ball mill and carry out mechanical live
Change, 300 mesh sieve is crossed after dry；
2) nano-silicon, agraphitic carbon, N- methyl pyrrole network alkanones are matched according to a certain percentage, it is equal that ultrasonic wave disperses 20min stirrings
It is even, by step 1) be sieved after product be uniformly mixed with nano-silicon solution, be placed under nitrogen protection in roller furnace calcine 4~
6h, calcination temperature are 600~700 DEG C, Temperature fall；
3) powder after Temperature fall is put into ball mill ball milling, is again placed in roller furnace after the completion of ball milling, in nitrogen protection
2~4h of lower calcining, calcination temperature are 1000~1500 DEG C, and natural cooling obtains negative material after being sieved except magnetic.
4. the preparation method of lithium battery composite negative pole material according to claim 3, it is characterised in that：The step
1) molar ratio of element is Mn in:Li：Co=1.6:0.621：0.2.
5. the preparation method of lithium battery composite negative pole material according to claim 4, it is characterised in that：In step 2),
In terms of mass parts, the nano-silicon be 20~40 parts, 80~100 parts of agraphitic carbon, 200~220 parts of N- methyl pyrrole networks alkanone.
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Cited By (2)
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| CN111180663A (en) * | 2018-11-13 | 2020-05-19 | 北方奥钛纳米技术有限公司 | Negative electrode material and preparation method thereof, negative plate and lithium ion battery |
| CN111244408A (en) * | 2019-12-26 | 2020-06-05 | 河南新太行电源股份有限公司 | Preparation method of negative electrode material of lithium ion power battery |
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| CN111244408A (en) * | 2019-12-26 | 2020-06-05 | 河南新太行电源股份有限公司 | Preparation method of negative electrode material of lithium ion power battery |
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