CN109585824A - A kind of preparation method of the porous manganate cathode material for lithium of spherical hollow - Google Patents
A kind of preparation method of the porous manganate cathode material for lithium of spherical hollow Download PDFInfo
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- CN109585824A CN109585824A CN201811412953.3A CN201811412953A CN109585824A CN 109585824 A CN109585824 A CN 109585824A CN 201811412953 A CN201811412953 A CN 201811412953A CN 109585824 A CN109585824 A CN 109585824A
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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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- 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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- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
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- H01M4/02—Electrodes composed of, or comprising, active material
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- H01M4/362—Composites
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- 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
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- 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
- H01M4/5825—Oxygenated metallic salts or polyanionic structures, e.g. borates, phosphates, silicates, olivines
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- 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
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- H01M4/02—Electrodes composed of, or comprising, active material
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- H01M4/624—Electric conductive fillers
- H01M4/625—Carbon or graphite
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Abstract
The invention discloses a kind of preparation methods of the porous manganate cathode material for lithium of spherical hollow, belong to lithium ion battery preparation technical field.This method specific steps include: to weigh lithium salts, manganese salt, glucose by 1: 2: 0.5~20 molar ratio and be configured to aqueous solution, it is transferred to after being sufficiently stirred in 50ml high-pressure hydrothermal reaction kettle and carries out insulation reaction, after cooled to room temperature, then washed, suction filtration, drying, LiMn can be obtained2O4The spherical core-shell structure of@C, then low temperature calcination to get arrive the porous manganate cathode material for lithium of spherical hollow of the invention.The advantages that present invention assists one step hydro thermal method using glucose, and self assembly prepares the manganate cathode material for lithium of the porous pattern of spherical hollow, has preparation process simple, easy to operate, low in cost.The positive electrode is of uniform size, morphology controllable, good dispersion, with excellent chemical property when using as anode material for lithium-ion batteries.
Description
Technical field
The invention belongs to lithium ion battery preparation technical fields, and in particular to a kind of porous lithium manganate lithium ion of spherical hollow
The preparation method of cell positive material.
Background technique
The LiMn2O4 of spinel structure is considered as most potential one of anode material for lithium-ion batteries.Traditional solid phase
It is sintered synthetic lithium manganate and needs higher temperature and longer reaction time, energy consumption is high, and particle size is not easy to control.In order to develop
The preparation of positive electrode with rapid kinetics, nanostructure mangaic acid lithium has received widespread attention, such as nano particle, nanometer
Line/nanometer rods etc..Especially nanometer perforated electrodes effective contact area for increasing electrolyte and positive electrode, shortens lithium ion
Diffusion length, lithium ion volume contraction and expansion caused by deintercalation repeatedly during buffer cycles.
Hydrothermal synthesis method can be such that aqueous solution intermediate ion is uniformly mixed, and product purity is high, and granularity and pattern are easy to control, be to obtain
The common preparation method of nano particle.Hydro-thermal method synthesizes LiMn2O4It is closely related with raw material and additive used.Such as: using two
When manganese oxide is as the source Mn, since its reactivity is poor, LiMn is synthesized2O4Required the hydro-thermal reaction time is longer, is up to 2-24
It；If using potassium permanganate and lithium hydroxide as raw material, while a certain amount of acetone is added, the organic solvents such as ethyl alcohol can shorten conjunction
At LiMn2O4The required hydro-thermal time.But these nano particles are easily reunited, unfavorable to the circulation and high rate performance of positive electrode.
Chinese invention patent (Authorization Notice No.: CN102931393B) provides a kind of LiMn of porous spherical structure2O4's
Preparation method.It is specific: by NH4HCO3And MnSO4Spheric manganese carbonate is settled out in alcohol solvent, after centrifugation, filtration washing
Calcining obtains porous spherical Mn2O3Presoma, the presoma and LiOH again pass by high-temperature calcination and obtain porous spherical LiMn2O4。
Chinese invention patent (Authorization Notice No. CN104409719B) provides a kind of porous spherical LiMn2O4Positive material
Preparation method for material.It is specific: a certain amount of hydrogen peroxide being added in the aqueous solution of manganese salt, under agitation, adds carbonic acid
Sodium and sodium hydroxide, and obtained precipitating is centrifuged, washs, dry, by the sediment and lithium carbonate after drying
It is calcined after mixing, the LiMn of porous spherical can be obtained2O4。
Above-mentioned preparation method is there are process complexity, and morphology controllable is bad, the defects of using corrosive reagents.Therefore, it seeks
A kind of simple process is sought, easy to operate, low in cost, the porous manganate cathode material for lithium of the spherical hollow of good dispersion has important
Practical significance.
Summary of the invention
The technical problem to be solved in the present invention is that having overcome the deficiencies of the prior art and provide a kind of simple and effective, it is based on
Hydro-thermal method one-step synthesis obtains LiMn2O4The core-shell structure of carbon ball is coated, and then the spherical hollow for obtaining self assembly is porous
LiMn2O4The preparation method of positive electrode.
In order to solve the above technical problems, the present invention is achieved by the following technical programs, include the following steps:
(1) by soluble lithium salt, soluble manganese salt, glucose, 1: 2: 0.5~20 mixing, is made mixing water in molar ratio
Solution, being sufficiently stirred dissolves it sufficiently；
(2) mixed aqueous solution prepared by step (1) is moved in high-pressure hydrothermal reaction kettle, is sealed, and in 140~200 DEG C
Heat preservation 5~for 24 hours；
(3) hydrothermal product that step (2) obtain is washed and is filtered through deionized water and dehydrated alcohol respectively；
(4) step (3) are washed into filtered product and 1~3h is dried under the conditions of 80 DEG C, room temperature to be dropped to carries out
Carefully grinding obtains LiMn2O4The spherical core-shell structure of@C；
(5) product that step (4) obtain is calcined with the heating rate of 1~4 DEG C/min 1 under the conditions of 400~550 DEG C~
20h can be obtained the porous LiMn of spherical hollow2O4。
Further, the soluble lithium salt in the step (1), soluble manganese salt, glucose mix at 1: 2: 5 in molar ratio
It closes.
Further, the high-pressure hydrothermal reaction kettle in the step (2) is the water heating kettle of inner liner polytetrafluoroethylene.
Further, step (5) the calcining heating rate is 4 DEG C/min.
Compared with prior art, the present invention has following technical effect that
(1) simple process that the present invention uses, green carbon source (glucose) template, preparation condition is mild, and calcination temperature is low,
Heat treatment time is short, saves the energy, low in cost.
(2) in hydrothermal reaction process of the invention, one-step synthesis obtains LiMn2O4, and effectively shorten synthesis LiMn2O4
Required the hydro-thermal reaction time.
(3) in hydrothermal reaction process of the invention, a step obtains LiMn in situ2O4The spherical core-shell structure of@C.
(4) for the present invention during low temperature calcination, carbon ball is calcined removing, and the spherical hollow for obtaining self assembly is porous
LiMn2O4Material, the scantling is uniform, morphology controllable, good dispersion.
(5) the porous LiMn of spherical hollow that the present invention obtains2O4Have when material is used as anode material for lithium-ion batteries
Excellent chemical property.
Detailed description of the invention
Fig. 1 is scanning electron microscope (SEM) photo that LiMn2O4 made from the embodiment of the present invention 1 coats carbon ball；
As shown in Figure 1, the carbon ball of LiMn2O4 cladding is about 5~10 μm.
Fig. 2 is X-ray diffraction (XRD) map of the porous LiMn2O4 of spherical hollow made from the embodiment of the present invention 2；
The map shows that product is single-phase LiMn2O4。
Fig. 3 is scanning electron microscope (SEM) photo of the porous LiMn2O4 of spherical hollow made from the embodiment of the present invention 2；
The photo shows that hollow porous LiMn has been prepared in the present invention2O4Material；The size of the hollow porous ball 1~
2μm。
Fig. 4 is the first charge-discharge curve under the porous LiMn2O4 1C of spherical hollow made from the embodiment of the present invention 2；
The map shows in 1C (148mAg-1) under multiplying power, there are two platforms in charging and discharging curve, about respectively in 4.0V
Near 4.15V, the capacity of first charge-discharge is respectively 114mAhg-1And 110mAhg-1。
Specific embodiment
In order to further appreciate that technology contents of the invention, the present invention, but this hair are described in detail below in conjunction with drawings and examples
It is bright to be not limited to following embodiments.
Embodiment 1
Weigh the LiNO of 0.6g3, the 50%Mn (NO of 4.04ml3)2Solution, the C of 8.6g6H12O6·H2O is dissolved into deionization
It in water, is sufficiently stirred, dissolves it sufficiently, then mixed aqueous solution is moved in 50ml reaction kettle, it is natural in 180 DEG C of reaction 12h
It is cooled to room temperature.Hydro-thermal reaction product carries out to the multiple washing of deionized water and dehydrated alcohol respectively, after suction filtration, in 80 DEG C
Under the conditions of dry 1h, LiMn can be obtained2O4The powder of the spherical core-shell structure of@C；After dry powder is carefully ground again, with 4 DEG C/
Min is warming up to 500 DEG C of calcining 5h, and the porous LiMn of spherical hollow can be obtained2O4Positive electrode.
Embodiment 2
Weigh the LiNO of 0.6g3, the 50%Mn (NO of 4.04ml3)2Solution, the C of 8.6g6H12O6·H2O is dissolved into deionization
It in water, is sufficiently stirred, then mixed aqueous solution is moved in 50ml reaction kettle, in 160 DEG C of reaction 12h, cooled to room temperature.It will
Hydro-thermal reaction product carries out the multiple washing of deionized water and dehydrated alcohol respectively, after suction filtration, the dry 1h under conditions of 80 DEG C,
LiMn can be obtained2O4The powder of the spherical core-shell structure of@C；Dry powder after carefully grinding, is warming up to 500 again with 4 DEG C/min
DEG C calcining 5h, the porous LiMn of spherical hollow can be obtained2O4Positive electrode.
Embodiment 3
Weigh the LiNO of 0.6g3, the 50%Mn (NO of 4.04ml3)2Solution, the C of 8.6g6H12O6·H2O is dissolved into deionization
It in water, is sufficiently stirred, then mixed aqueous solution is moved in 50ml reaction kettle, in 200 DEG C of reaction 6h, cooled to room temperature.It will
Hydro-thermal reaction product carries out the multiple washing of deionized water and dehydrated alcohol respectively, after suction filtration, the dry 1h under conditions of 80 DEG C,
LiMn can be obtained2O4The powder of the spherical core-shell structure of@C；Dry powder after carefully grinding, is warming up to 450 again with 1 DEG C/min
DEG C calcining 8h, the porous LiMn of spherical hollow can be obtained2O4Positive electrode.
Embodiment 4
Weigh the LiNO of 0.6g3, the 50%Mn (NO of 4.04ml3)2Solution, the C of 17.2g6H12O6·H2O, be dissolved into from
It in sub- water, is sufficiently stirred, then mixed aqueous solution is moved in 50ml reaction kettle, for 24 hours in 140 DEG C of reactions, cooled to room temperature.
Hydro-thermal reaction product carries out to the multiple washing of deionized water and dehydrated alcohol respectively, it is dry under conditions of 80 DEG C after suction filtration
3h can obtain LiMn2O4The powder of the spherical core-shell structure of@C；Dry powder after carefully grinding, is warming up to again with 1 DEG C/min
550 DEG C of calcining 5h, can be obtained the porous LiMn of spherical hollow2O4Positive electrode.
Claims (4)
1. a kind of preparation method of the porous manganate cathode material for lithium of spherical hollow, it is characterised in that the following steps are included:
(1) by soluble lithium salt, soluble manganese salt, glucose, 1: 2: 0.5~20 mixing, is made mixed aqueous solution in molar ratio,
Being sufficiently stirred dissolves it sufficiently；
(2) mixed aqueous solution prepared by step (1) is moved in high-pressure hydrothermal reaction kettle, is sealed, and kept the temperature in 140~200 DEG C
Reaction 5~for 24 hours；
(3) hydrothermal product that step (2) obtain is washed and is filtered through deionized water and dehydrated alcohol respectively；
(4) step (3) are washed into filtered product and 1~3h is dried under the conditions of 80 DEG C, room temperature to be dropped to, it is careful to carry out
Grinding obtains LiMn2O4The spherical core-shell structure of@C；
(5) product that step (4) obtain is calcined into 1~20h with the heating rate of 1~4 DEG C/min under the conditions of 400~550 DEG C,
It can be obtained the porous LiMn of spherical hollow2O4。
2. the preparation method of the porous manganate cathode material for lithium of spherical hollow as described in claim 1, which is characterized in that the step
Suddenly the soluble lithium salt in (1), soluble manganese salt, glucose 1: 2: 5 mixing in molar ratio.
3. the preparation method of the porous manganate cathode material for lithium of spherical hollow as described in claim 1, which is characterized in that the step
Suddenly the high-pressure hydrothermal reaction kettle in (2) is the water heating kettle of inner liner polytetrafluoroethylene.
4. the preparation method of the porous manganate cathode material for lithium of spherical hollow as described in claim 1, which is characterized in that the step
Suddenly (5) calcining heating rate is 4 DEG C/min.
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP3846601B2 (en) * | 1996-06-13 | 2006-11-15 | 株式会社ジーエス・ユアサコーポレーション | Positive electrode active material for lithium battery, method for producing the same, and battery comprising the active material |
| CN102280617A (en) * | 2011-07-06 | 2011-12-14 | 中国科学院过程工程研究所 | Carbon material modified composite lithium manganese oxide cathode material applied to lithium ion battery and preparation method thereof |
| CN102790210A (en) * | 2012-08-23 | 2012-11-21 | 广州市香港科大霍英东研究院 | Method for preparing cathode material lithium manganate of lithium ion battery by supercritical hydrothermal reaction |
| CN104600286A (en) * | 2015-01-29 | 2015-05-06 | 扬州大学 | Preparation method of positive active material hollow spherical lithium manganate of lithium ion battery |
| CN106025260A (en) * | 2016-07-06 | 2016-10-12 | 上海交通大学 | Ternary cathode material of hollow spherical nano-structure and preparing method thereof |
-
2018
- 2018-11-23 CN CN201811412953.3A patent/CN109585824A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP3846601B2 (en) * | 1996-06-13 | 2006-11-15 | 株式会社ジーエス・ユアサコーポレーション | Positive electrode active material for lithium battery, method for producing the same, and battery comprising the active material |
| CN102280617A (en) * | 2011-07-06 | 2011-12-14 | 中国科学院过程工程研究所 | Carbon material modified composite lithium manganese oxide cathode material applied to lithium ion battery and preparation method thereof |
| CN102790210A (en) * | 2012-08-23 | 2012-11-21 | 广州市香港科大霍英东研究院 | Method for preparing cathode material lithium manganate of lithium ion battery by supercritical hydrothermal reaction |
| CN104600286A (en) * | 2015-01-29 | 2015-05-06 | 扬州大学 | Preparation method of positive active material hollow spherical lithium manganate of lithium ion battery |
| CN106025260A (en) * | 2016-07-06 | 2016-10-12 | 上海交通大学 | Ternary cathode material of hollow spherical nano-structure and preparing method thereof |
Non-Patent Citations (1)
| Title |
|---|
| 宋修梅: "LiMn2O4正极材料的制备及第一性原理研究", 《中国优秀硕士学位论文全文数据库 工程科技Ⅱ辑》 * |
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Application publication date: 20190405 |