CN103633308A - Lithium, nickel, cobalt, aluminum and oxygen-rich cathode material and preparation method thereof - Google Patents

Lithium, nickel, cobalt, aluminum and oxygen-rich cathode material and preparation method thereof Download PDF

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Publication number
CN103633308A
CN103633308A CN201310615074.1A CN201310615074A CN103633308A CN 103633308 A CN103633308 A CN 103633308A CN 201310615074 A CN201310615074 A CN 201310615074A CN 103633308 A CN103633308 A CN 103633308A
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positive electrode
nickel cobalt
sintering
solution
cobalt
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陈涨宗
袁徐俊
沙金
沈震雷
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NINGBO JINHE LITHIUM BATTERY MATERIAL CO., LTD.
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Ningbo Jinhe New Materials Co Ltd
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    • HELECTRICITY
    • H01BASIC ELECTRIC ELEMENTS
    • H01MPROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00Electrodes
    • H01M4/02Electrodes composed of, or comprising, active material
    • H01M4/36Selection of substances as active materials, active masses, active liquids
    • H01M4/362Composites
    • H01M4/366Composites as layered products
    • HELECTRICITY
    • H01BASIC ELECTRIC ELEMENTS
    • H01MPROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00Electrodes
    • H01M4/02Electrodes composed of, or comprising, active material
    • H01M4/36Selection of substances as active materials, active masses, active liquids
    • H01M4/48Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides
    • H01M4/52Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides of nickel, cobalt or iron
    • H01M4/525Selection 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
    • HELECTRICITY
    • H01BASIC ELECTRIC ELEMENTS
    • H01MPROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00Secondary cells; Manufacture thereof
    • H01M10/05Accumulators with non-aqueous electrolyte
    • H01M10/052Li-accumulators
    • H01M10/0525Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
    • YGENERAL 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
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02EREDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/10Energy storage using batteries

Abstract

The invention discloses a lithium, nickel, cobalt, aluminum and oxygen-rich cathode material. The lithium, nickel, cobalt, aluminum and oxygen-rich cathode material has the general formula of Li1+n Ni0.7+x Co0.3-x-y-z Aly Mz O2, wherein x is more than 0 and less than 0.3, y is more than 0.01 and less than 0.1, z is more than or equal to 0 and less than 0.03, x+y+z is less than 0.3, n is more than 0 and less than 0.25, and M is one or combination of more in cobalt, manganese, magnesium, titanium, zirconium, fluorine, boron and aluminum. The method comprises the following steps of preparing a nickel-cobalt-aluminum precursor; then, mixing the nickel-cobalt-aluminum precursor with an excessive lithium source; and sintering at high temperature, and removing residual lithium on the surfaces of the particles by a washing and cladding way so as to reduce the content of impurity lithium in a finished product and the pH value, so that the lithium, nickel, cobalt, aluminum and oxygen-rich cathode material can be prepared. The lithium, nickel, cobalt, aluminum and oxygen-rich cathode material is low in cation mixing degree and excellent in electrical property and cycle life; the preparation method is simple in technology, convenient to operate, high in degree of automation and low in pollution.

Description

A kind of rich lithium nickel cobalt alumina positive electrode and preparation method thereof
Technical field
The present invention relates to technical field of lithium-ion battery, especially refer to a kind of anode material for lithium-ion batteries, refer to particularly a kind of rich lithium nickel cobalt alumina positive electrode and preparation method thereof.
Background technology
Lithium ion battery, as novel green power supply, has voltage high, and energy density is large, good cycle, the plurality of advantages such as self discharge is little, memoryless benefit, have been widely used in the fields such as mobile phone, notebook computer, UPS, various portable power tool, electronic instrument.Along with scientific and technical progress, people also more come also high to the requirement of lithium ion battery, people need the lithium rechargeable battery that service time is longer, size is less, weight is lighter, this just requires its positive electrode need to meet high-energy-density, high security and good cycle performance etc., but all there is certain defect in the lithium of the cobalt of ripe application acid in the market, LiMn2O4, LiFePO4 and conventional nickel-cobalt-manganese ternary material, can not meet above-mentioned requirements simultaneously.And lithium nickel cobalt alumina positive electrode has than the much higher characteristic of above-mentioned positive electrode capacity, by suitable processing is carried out in the aspects such as its synthetic method, doping vario-property, improve its cycle performance and security performance, be expected to make lithium nickel cobalt alumina positive electrode to become the leading anode material for lithium-ion batteries in market.
The synthetic method of existing lithium nickel cobalt alumina positive electrode is mainly solid-phase synthesis and liquid phase synthesizing method.Solid-phase synthesis generally carries out sintering after compound, lithium source and the doping element compound mixing with nickel cobalt aluminium, but this solid phase mixing mode can not reach the even of atomic level, and performance is difficult to give full play to; Although liquid phase synthesizing method can head it off, complex process, yield poorly.From actual production angle, consider, solid-phase synthesis is prepared lithium nickel cobalt alumina positive electrode and is more suitable for undoubtedly large-scale production, but working condition is harsh, controls difficulty, particularly sintering atmosphere is required strictly, must be in oxygen atmosphere sintering.In addition, the control of sintering temperature is also comparatively difficult, because its temperature domain of walker is narrower, temperature is low reacts insufficient, and temperature height can decompose, and is difficult to complete reaction.And there is Ni in high-nickel material synthetic 2+be difficult to completely to Ni 3+change, can cause Ni in high-temperature sintering process 2+and Li +produce the phenomenon of cation mixing, also can make the poor heat stability of material and cause that irreversible capacity is high first.
Summary of the invention
Technical problem to be solved by this invention is for above-mentioned prior art present situation, and provide cation mixing degree low, a kind of rich lithium nickel cobalt alumina positive electrode that electrical property and cycle life are outstanding, and provide that technique is simple, easy to operate, automaticity is high, pollute the preparation method of little a kind of rich lithium nickel cobalt alumina positive electrode.
The present invention solves the problems of the technologies described above adopted technical scheme:
A rich lithium nickel cobalt alumina positive electrode, wherein: the general formula of rich lithium nickel cobalt alumina positive electrode is Li 1+nni 0.7+xco 0.3-x-y-zal ym zo 20 < x < 0.3 wherein, 0.01 < y < 0.1,0≤z < 0.03, x+y+z < 0.3,0 < n < 0.25, M element is one or more in cobalt, manganese, magnesium, titanium, zirconium, fluorine, boron, aluminium.
The technical measures of optimizing also comprise:
It is spherical that the molecular structure of above-mentioned rich lithium nickel cobalt alumina positive electrode is class, and the longitudinal radius of molecular structure and the lateral radius ratio of rich lithium nickel cobalt alumina positive electrode are 0.5 to 2.0.
A preparation method for rich lithium nickel cobalt alumina positive electrode, comprises the following steps:
Step 1: nickel cobalt aluminium presoma is carried out to pre-oxidation calcination processing, and pre-oxidation calcination processing temperature is 300 ℃ to 800 ℃, and the pre-oxidation calcination processing time is 5h to 25h, and cooling with stove after pre-oxidation calcination processing, fragmentation is sieved;
Step 2: be to carry out sintering after 1:1.02 to 1:1.25 mixes according to the mol ratio of metal cation and lithium ion by the mixture after sieving in step 1 and lithium salt solution, sintering temperature is 650 ℃ to 950 ℃, sintering sintering 5h to 25h, during sintering, in stove, continue to pass into oxygen or air, cooling with stove after sintering, fragmentation is sieved, and obtains rich lithium nickel cobalt alumina positive electrode intermediate product;
Step 3: the intermediate product obtaining in step 2 is added in high-speed mixer and mixed with detergent solution, and incorporation time is 0.1h to 2h, after mixing carries out solidliquid mixture suction filtration and dries, and sieves;
Step 4: the mixed product that sieves in step 3 is carried out to sintering processes, and sintering temperature is 200 ℃ to 800 ℃, and sintering time is 5h to 30h, cooling with stove after sintering, obtains rich lithium nickel cobalt alumina positive electrode after sieving.
Before above-mentioned step 1, be also provided with nickel cobalt aluminium presoma preparation process: nickel salt solution, cobalt salt solution and aluminum salt solution are mixed, concentration of metal ions after mixing in solution is 0.5mol/l to 2.0mol/l, again solution stream after enveloping agent solution, precipitant solution and mixing are added in reactor, add thermal agitation and carry out precipitation reaction, the slurry starting overflowing after fully reacting carries out Separation of Solid and Liquid, solid product after separation, after washing, drying, obtains spherical nickel cobalt aluminium presoma.
Above-mentioned detergent solution is the mixed liquor of deionized water or ethanol or deionized water and ethanol.
Above-mentioned precipitant solution is NaOH precipitant solution.
In above-mentioned step 3 mixed process, add covering; At least one in covering containing element cobalt, manganese, magnesium, titanium, zirconium, fluorine, boron, aluminium.
Above-mentioned nickel salt solution is at least one in nickel sulfate solution, nickel chloride solution, and cobalt salt solution is at least one in cobalt sulfate solution, cobalt chloride solution, and aluminum salt solution is at least one in aluminum sulfate solution, liquor alumini chloridi.
In above-mentioned step 1, nickel ion, cobalt ions, aluminum ions mol ratio are 0.75 ~ 0.85:0.1 ~ 0.2:0.03 ~ 0.07.
Lithium salts in above-mentioned step 3 is at least one in lithium carbonate, lithium hydroxide, lithium acetate, lithium oxalate.
Compared with prior art, the invention has the advantages that:
Nickel cobalt aluminium presoma is mixed with excessive lithium source, then at high temperature carry out sintering, again by the coated means of washing, remove the residual lithium of particle surface, reduce impurity lithium content and the pH value of finished product, thereby obtain perfect structure, physicochemical property and electrical property be good rich lithium nickel cobalt alumina positive electrode all.The rich lithium nickel cobalt alumina positive electrode synthesizing by this method, cation mixing degree is low, and electrical property and cycle life are outstanding; On the other hand, reduce the dependence of NCA material sintering process to oxygen in the past, can in air atmosphere, carry out sintering and synthesize, reduced production difficulty.Rich lithium nickel cobalt alumina positive electrode stability and the consistency by preparation method of the present invention, prepared are better, can realize automaticity high, and simple to operate, environmental pollution is few, is conducive to suitability for industrialized production; Adopt in addition in positive electrode prepared by the present invention that nickel content is high and cobalt content is low, greatly reduced the cost of raw material.
The rich lithium nickel of the lithium ion battery cobalt alumina positive electrode that utilizes the present invention to prepare, it is spherical that crystal size is evenly distributed, crystal morphology is class, has good bulk density; Its specific capacity can reach 180mAh/g ~ 200 mAh/g, and 1C discharges and recharges 300 weeks circulation volume conservation rates and is greater than 90%, and tap density is 2.3 ~ 2.9g/cm 3, average grain diameter is 5 ~ 20um, and it is low that impurity lithium content is less than 0.2%, 85 ℃ of high temperature flatulence rate, and the reversible capacity between 3.0V ~ 4.3V is greater than 180Ah/g; Utilize the rich lithium nickel of lithium ion battery cobalt alumina positive electrode prepared by the present invention to there is very high capacity and good cycle performance, have good anti-high temperature flatulence performance simultaneously.
Accompanying drawing explanation
Fig. 1 is the SEM collection of illustrative plates of the product of the embodiment of the present invention one;
Fig. 2 is the XRD collection of illustrative plates of the product of the embodiment of the present invention one;
Fig. 3 is for making the capability retention figure of the battery of anode with the product of the embodiment of the present invention one.
Embodiment
Below in conjunction with accompanying drawing, the embodiment of the present invention is described in further detail.
A rich lithium nickel cobalt alumina positive electrode, the general formula of rich lithium nickel cobalt alumina positive electrode is Li 1+nni 0.7+xco 0.3-x-y-zal ym zo 20 < x < 0.3 wherein, 0.01 < y < 0.1,0≤z < 0.03, x+y+z < 0.3,0 < n < 0.25, M element is one or more in cobalt, manganese, magnesium, titanium, zirconium, fluorine, boron, aluminium; It is spherical that the molecular structure of rich lithium nickel cobalt alumina positive electrode is class, 0.5 < a/b < 2.0 in its SEM collection of illustrative plates, longitudinal radius that wherein a is material molecule, the lateral radius that b is material molecule.
A preparation method for rich lithium nickel cobalt alumina positive electrode, comprises the following steps:
Step 1: the preparation of nickel cobalt aluminium presoma: nickel salt solution, cobalt salt solution and aluminum salt solution are mixed, concentration of metal ions after mixing in solution is 0.5mol/l to 2.0mol/l, again solution stream after enveloping agent solution, precipitant solution and described mixing are added in reactor, add thermal agitation and carry out precipitation reaction, the slurry starting overflowing after fully reacting carries out Separation of Solid and Liquid, solid product after separation, after washing, drying, obtains spherical nickel cobalt aluminium presoma; The nickel cobalt aluminium presoma occurring in claim 3 refers to the nickel cobalt aluminium compound of using for the preparation of lithium battery.Precipitant solution is NaOH precipitant solution; Enveloping agent solution is can be with metalion forms the compound solution of complex ion, can be cyanide, hydroxide, citrate, pyrophosphate, thiosulfate, sulphite etc.
Step 2: the nickel cobalt aluminium presoma obtaining in step 1 is carried out to pre-oxidation calcination processing, and pre-oxidation calcination processing temperature is 300 ℃ to 800 ℃, and the pre-oxidation calcination processing time is 5h to 25h, and cooling with stove after pre-oxidation calcination processing, fragmentation is sieved;
Step 3: be to carry out sintering after 1:1.02 to 1:1.25 mixes according to the mol ratio of metal cation and lithium ion by the mixture after sieving in step 2 and lithium salt solution, sintering temperature is 650 ℃ to 950 ℃, sintering sintering 5h to 25h, during sintering, in stove, continue to pass into oxygen or air, cooling with stove after sintering, fragmentation is sieved, and obtains rich lithium nickel cobalt alumina positive electrode intermediate product;
Step 4: the intermediate product obtaining in step 3 is added in high-speed mixer and mixed with detergent solution, and incorporation time is 0.1h to 2h, after mixing carries out solidliquid mixture suction filtration and dries, and sieves; Detergent solution is the mixed liquor of deionized water or ethanol or deionized water and ethanol;
Step 5: the mixed product that sieves in step 4 is carried out to sintering processes, and sintering temperature is 200 ℃ to 800 ℃, and sintering time is 5h to 30h, cooling with stove after sintering, obtains rich lithium nickel cobalt alumina positive electrode after sieving.
In described step 4 mixed process, add covering; At least one in covering containing element cobalt, manganese, magnesium, titanium, zirconium, fluorine, boron, aluminium.
In described step 1, nickel salt is at least one in nickelous sulfate, nickel chloride, and cobalt salt is at least one in cobaltous sulfate, cobalt chloride, and aluminium salt is at least one in aluminum sulfate, aluminium chloride.
In described step 1, nickel ion, cobalt ions, aluminum ions mol ratio are 0.75 ~ 0.85:0.1 ~ 0.2:0.03 ~ 0.07.
Lithium salts in described step 3 is at least one in lithium carbonate, lithium hydroxide, lithium acetate, lithium oxalate.
Below in conjunction with experiment, be described further:
Embodiment mono-:
Step 1: the preparation of nickel cobalt aluminium presoma: the nickel sulfate solution that is 0.75:0.20:0.05 by the mol ratio of Ni:Co:Al, cobalt sulfate solution, aluminum sulfate solution are that raw material mixes, concentration of metal ions after mixing in solution is 1.0M, again by enveloping agent solution, precipitant solution together with solution after described mixing and stream add in the reactor that end liquid is housed, add thermal agitation and carry out precipitation reaction, the slurry starting overflowing after fully reacting carries out Separation of Solid and Liquid, solid product after separation, after washing, drying, obtains spherical nickel cobalt aluminium presoma;
Step 2: the nickel cobalt aluminium presoma just obtaining in step 1 carries out pre-oxidation calcination processing, and pre-oxidation calcination processing temperature is 650 ℃, and the pre-oxidation calcination processing time is 12h, and cooling with stove after pre-oxidation calcination processing, fragmentation is sieved;
Step 3: be to carry out sintering after 1:1.1 mixes according to the mol ratio of metal cation and lithium ion by the mixture after sieving in step 2 and lithium carbonate, sintering temperature is 900 ℃, sintering sintering 20h, during sintering, in stove, continue to pass into air, cooling with stove after sintering, fragmentation is sieved, and obtains nickel cobalt alumina positive electrode intermediate product;
Step 4: the intermediate product obtaining in step 3 is added in high-speed mixer and mixed with detergent solution, add covering simultaneously; Incorporation time is 1h, after mixing, solidliquid mixture is carried out to suction filtration and dries, and sieves; In the covering of the present embodiment, comprise cobalt element.
Step 5: the mixed product that sieves in step 4 is carried out to sintering processes, and sintering temperature is 600 ℃, and sintering time is 10h, cooling with stove after sintering, obtains nickel cobalt alumina positive electrode after sieving.
The tap density 2.46g/cm of the nickel cobalt alumina positive electrode of preparing in the present embodiment after testing, 3, impurity lithium content is 0.06%, and this positive electrode processing characteristics is good, and while being made into battery, capacity is 186mAh/g, and it is 95.7% that 1C discharges and recharges 300 weeks capability retentions, and battery performance is good, and without disadvantageous changes such as bulging, 85 ℃ of thickness conservation rates are 106.2%.
Embodiment bis-:
Step 1: the preparation of nickel cobalt aluminium presoma: the nickel sulfate solution that is 0.77:0.18:0.05 by the mol ratio of Ni:Co:Al, cobalt sulfate solution, aluminum sulfate solution are that raw material mixes, concentration of metal ions after mixing in solution is 1.0M, again by enveloping agent solution, precipitant solution together with solution after described mixing and stream add in the reactor that end liquid is housed, add thermal agitation and carry out precipitation reaction, the slurry starting overflowing after fully reacting carries out Separation of Solid and Liquid, solid product after separation, after washing, drying, obtains spherical nickel cobalt aluminium presoma;
Step 2: the nickel cobalt aluminium presoma just obtaining in step 1 carries out pre-oxidation calcination processing, and pre-oxidation calcination processing temperature is 500 ℃, and the pre-oxidation calcination processing time is 12h, and cooling with stove after pre-oxidation calcination processing, fragmentation is sieved;
Step 3: be to carry out sintering after 1:1.12 mixes according to the mol ratio of metal cation and lithium ion by the mixture after sieving in step 2 and lithium hydroxide, sintering temperature is 850 ℃, sintering sintering 18h, during sintering, in stove, continue to pass into air, cooling with stove after sintering, fragmentation is sieved, and obtains nickel cobalt alumina positive electrode intermediate product;
Step 4: the intermediate product obtaining in step 3 is added in high-speed mixer and mixed with detergent solution, and incorporation time is 1.5h, after mixing carries out solidliquid mixture suction filtration and dries, and sieves;
Step 5: the mixed product that sieves in step 4 is carried out to sintering processes, and sintering temperature is 700 ℃, and sintering time is 12h, cooling with stove after sintering, obtains nickel cobalt alumina positive electrode after sieving.
After testing, the tap density 2.43g/cm3 of the rich lithium nickel cobalt alumina positive electrode of preparing in the present embodiment, impurity lithium content is 0.05%, this positive electrode processing characteristics is good, and while being made into battery, capacity is 189mAh/g, it is 95.5% that 1C discharges and recharges 300 weeks circulation conservation rates, battery performance is good, and without disadvantageous changes such as bulging, 85 ℃ of thickness conservation rates are 107.1%.
Embodiment tri-:
Step 1: the preparation of nickel cobalt aluminium presoma: the nickel chloride solution that is 0.8:0.15:0.05 by the mol ratio of Ni:Co:Al, cobalt chloride solution, liquor alumini chloridi are that raw material mixes, concentration of metal ions after mixing in solution is 1.5M, again by enveloping agent solution, precipitant solution together with solution after described mixing and stream add in the reactor that end liquid is housed, add thermal agitation and carry out precipitation reaction, the slurry starting overflowing after fully reacting carries out Separation of Solid and Liquid, solid product after separation, after washing, drying, obtains spherical nickel cobalt aluminium presoma;
Step 2: the nickel cobalt aluminium presoma just obtaining in step 1 carries out pre-oxidation calcination processing, and pre-oxidation calcination processing temperature is 450 ℃, and the pre-oxidation calcination processing time is 12h, and cooling with stove after pre-oxidation calcination processing, fragmentation is sieved;
Step 3: be to carry out sintering after 1:1.15 mixes according to the mol ratio of metal cation and lithium ion by the mixture after sieving in step 2 and lithium acetate, sintering temperature is 830 ℃, sintering sintering 15h, during sintering, in stove, continue to pass into oxygen, cooling with stove after sintering, fragmentation is sieved, and obtains nickel cobalt alumina positive electrode intermediate product;
Step 4: the intermediate product obtaining in step 3 is added in high-speed mixer and mixed with detergent solution, add covering simultaneously; Incorporation time is 2h, after mixing, solidliquid mixture is carried out to suction filtration and dries, and sieves; In the covering of the present embodiment, comprise manganese, magnesium elements.
Step 5: the mixed product that sieves in step 4 is carried out to sintering processes, and sintering temperature is 550 ℃, and sintering time is 12h, cooling with stove after sintering, obtains nickel cobalt alumina positive electrode after sieving.
After testing, the tap density 2.49g/cm3 of the rich lithium nickel cobalt alumina positive electrode of preparing in the present embodiment, impurity lithium content is 0.07%, this positive electrode processing characteristics is good, and while being made into battery, capacity is 192mAh/g, it is 95.2% that 1C discharges and recharges 300 weeks circulation conservation rates, battery performance is good, and without disadvantageous changes such as bulging, 85 ℃ of thickness conservation rates are 108.7%.
Embodiment tetra-:
Step 1: the preparation of nickel cobalt aluminium presoma: the nickel chloride solution that is 0.83:0.1:0.07 by the mol ratio of Ni:Co:Al, cobalt chloride solution, liquor alumini chloridi are that raw material mixes, concentration of metal ions after mixing in solution is 1.5M, again by enveloping agent solution, precipitant solution together with solution after described mixing and stream add in the reactor that end liquid is housed, add thermal agitation and carry out precipitation reaction, the slurry starting overflowing after fully reacting carries out Separation of Solid and Liquid, solid product after separation, after washing, drying, obtains spherical nickel cobalt aluminium presoma;
Step 2: the nickel cobalt aluminium presoma just obtaining in step 1 carries out pre-oxidation calcination processing, and pre-oxidation calcination processing temperature is 480 ℃, and the pre-oxidation calcination processing time is 12h, and cooling with stove after pre-oxidation calcination processing, fragmentation is sieved;
Step 3: be to carry out sintering after 1:1.1 mixes according to the mol ratio of metal cation and lithium ion by the mixture after sieving in step 2 and lithium oxalate, sintering temperature is 800 ℃, sintering sintering 12h, during sintering, in stove, continue to pass into air, cooling with stove after sintering, fragmentation is sieved, and obtains nickel cobalt alumina positive electrode intermediate product;
Step 4: the intermediate product obtaining in step 3 is added in high-speed mixer and mixed with detergent solution, add covering simultaneously; Incorporation time is 2h, after mixing, solidliquid mixture is carried out to suction filtration and dries, and sieves; In the covering of the present embodiment, comprise titanium, zr element.
Step 5: the mixed product that sieves in step 4 is carried out to sintering processes, and sintering temperature is 450 ℃, and sintering time is 12h, cooling with stove after sintering, obtains nickel cobalt alumina positive electrode after sieving.
After testing, the tap density 2.48g/cm3 of the rich lithium nickel cobalt alumina positive electrode of preparing in the present embodiment, impurity lithium content is 0.06%, this positive electrode processing characteristics is good, and while being made into battery, capacity is 190mAh/g, it is 96.2% that 1C discharges and recharges 300 weeks circulation conservation rates, battery performance is good, and without disadvantageous changes such as bulging, 85 ℃ of thickness conservation rates are 107.5%.
Embodiment five:
Step 1: the preparation of nickel cobalt aluminium presoma: the nickel chloride solution that is 0.85:0.12:0.03 by the mol ratio of Ni:Co:Al, cobalt chloride solution, liquor alumini chloridi are that raw material mixes, concentration of metal ions after mixing in solution is 1.5M, again by enveloping agent solution, precipitant solution together with solution after described mixing and stream add in the reactor that end liquid is housed, add thermal agitation and carry out precipitation reaction, the slurry starting overflowing after fully reacting carries out Separation of Solid and Liquid, solid product after separation, after washing, drying, obtains spherical nickel cobalt aluminium presoma;
Step 2: the nickel cobalt aluminium presoma just obtaining in step 1 carries out pre-oxidation calcination processing, and pre-oxidation calcination processing temperature is 600 ℃, and the pre-oxidation calcination processing time is 10h, and cooling with stove after pre-oxidation calcination processing, fragmentation is sieved;
Step 3: be to carry out sintering after 1:1.09 mixes according to the mol ratio of metal cation and lithium ion by the mixture after sieving in step 2 and lithium carbonate, sintering temperature is 770 ℃, sintering sintering 10h, during sintering, in stove, continue to pass into air, cooling with stove after sintering, fragmentation is sieved, and obtains nickel cobalt alumina positive electrode intermediate product;
Step 4: the intermediate product obtaining in step 3 is added in high-speed mixer and mixed with detergent solution, add covering simultaneously; Incorporation time is 2h, after mixing, solidliquid mixture is carried out to suction filtration and dries, and sieves; In the covering of the present embodiment, comprise fluorine, boron, aluminium element.
Step 5: the mixed product that sieves in step 4 is carried out to sintering processes, and sintering temperature is 550 ℃, and sintering time is 12h, cooling with stove after sintering, obtains nickel cobalt alumina positive electrode after sieving.
After testing, the tap density 2.45g/cm3 of the rich lithium nickel cobalt alumina positive electrode of preparing in the present embodiment, impurity lithium content is 0.08%, this positive electrode processing characteristics is good, and while being made into battery, capacity is 194mAh/g, it is 95.1% that 1C discharges and recharges 300 weeks circulation conservation rates, battery performance is good, and without disadvantageous changes such as bulging, 85 ℃ of thickness conservation rates are 109.1%.
Compare with existing preparation method:
Step 1: the preparation of nickel cobalt aluminium presoma: be that raw material mixes by Ni:Co:Al mol ratio 0.75:0.20:0.05 nickel sulfate solution, cobalt sulfate solution, aluminum sulfate solution, concentration of metal ions after mixing in solution is 1.0 mol/L, again by enveloping agent solution, precipitant solution together with solution after described mixing and stream add in the reactor that end liquid is housed, add thermal agitation and carry out precipitation reaction, the slurry starting overflowing after fully reacting carries out Separation of Solid and Liquid, solid product after separation, after washing, drying, obtains spherical nickel cobalt aluminium presoma;
Step 2: the nickel cobalt aluminium presoma obtaining in step 1 is carried out to pre-oxidation calcination processing, and sintering temperature is 650 ℃, sintering 12h, cooling with stove after sintering, fragmentation is sieved;
Step 3: the mixture after sieving in step 2 and lithium salts are mixed to laggard row according to metal sun and Li ion mol ratio 1:1.02 and carry out high-temperature calcination, sintering temperature is 900 ℃, sintering 20h, continue during this time to pass into oxygen, cooling with stove after sintering, fragmentation obtains lithium nickel cobalt alumina positive electrode after sieving.
After testing, the tap density 2.43g/cm3 of lithium nickel cobalt alumina positive electrode prepared by this method, impurity lithium content is 0.35%, this positive electrode processing characteristics is poor, easily produces jelly phenomenon, while being made into battery, capacity is 178mAh/g, it is 84.3% that 1C discharges and recharges 300 weeks circulation conservation rates, and battery bulging phenomenon is serious, 85 ℃ high temperature thickness conservation rates 134.3%.
Embodiment data and comparative example data are compared as follows:
Numbering Impurity lithium content Capacity mAh/g 300 weeks circulation volume conservation rates The high temperature thickness conservation rate of 85 ℃/4h
Comparative example 0.35% 178 84.3% 134.3%
Embodiment mono- 0.05% 186 95.7% 106.2%
Embodiment bis- 0.05% 189 95.5% 107.1%
Embodiment tri- 0.07% 192 95.0% 108.0%
Embodiment tetra- 0.06% 190 96.2% 107.5%
Embodiment five 0.08% 194 95.1% 109.1%
In above-described embodiment, while choosing the two-end-point of corresponding span during value, little on experimental result impact.
In above-described embodiment, nickel salt, cobalt salt, aluminium salt are chosen the mixture of sulfate, hydrochloride or sulfate and hydrochloride, all do not affect experimental result.
Most preferred embodiment of the present invention is illustrated, and the various variations of being made by those of ordinary skills or remodeling can not depart from the scope of the present invention.

Claims (10)

1. a rich lithium nickel cobalt alumina positive electrode, is characterized in that: the general formula of described rich lithium nickel cobalt alumina positive electrode is Li 1+nni 0.7+xco 0.3-x-y-zal ym zo 20 < x < 0.3 wherein, 0.01 < y < 0.1,0≤z < 0.03, x+y+z < 0.3,0 < n < 0.25, M element is one or more in cobalt, manganese, magnesium, titanium, zirconium, fluorine, boron, aluminium.
2. a kind of rich lithium nickel cobalt alumina positive electrode according to claim 1, it is characterized in that: it is spherical that the molecular structure of described rich lithium nickel cobalt alumina positive electrode is class, and the longitudinal radius of molecular structure and the lateral radius ratio of described rich lithium nickel cobalt alumina positive electrode are 0.5 to 2.0.
3. a preparation method for rich lithium nickel cobalt alumina positive electrode, is characterized in that: comprise the following steps:
Step 1: nickel cobalt aluminium presoma is carried out to pre-oxidation calcination processing, and pre-oxidation calcination processing temperature is 300 ℃ to 800 ℃, and the pre-oxidation calcination processing time is 5h to 25h, and cooling with stove after pre-oxidation calcination processing, fragmentation is sieved;
Step 2: be to carry out sintering after 1:1.02 to 1:1.25 mixes according to the mol ratio of metal cation and lithium ion by the mixture after sieving in step 1 and lithium salt solution, sintering temperature is 650 ℃ to 950 ℃, sintering sintering 5h to 25h, during sintering, in stove, continue to pass into oxygen or air, cooling with stove after sintering, fragmentation is sieved, and obtains rich lithium nickel cobalt alumina positive electrode intermediate product;
Step 3: the intermediate product obtaining in step 2 is added in high-speed mixer and mixed with detergent solution, and incorporation time is 0.1h to 2h, after mixing carries out solidliquid mixture suction filtration and dries, and sieves;
Step 4: the mixed product that sieves in step 3 is carried out to sintering processes, and sintering temperature is 200 ℃ to 800 ℃, and sintering time is 5h to 30h, cooling with stove after sintering, obtains rich lithium nickel cobalt alumina positive electrode after sieving.
4. the preparation method of a kind of rich lithium nickel cobalt alumina positive electrode according to claim 3, it is characterized in that: before described step 1, be also provided with nickel cobalt aluminium presoma preparation process: by nickel salt solution, cobalt salt solution and aluminum salt solution mix, concentration of metal ions after mixing in solution is 0.5mol/l to 2.0mol/l, again by enveloping agent solution, after precipitant solution and mixing, solution stream add in reactor, add thermal agitation and carry out precipitation reaction, the slurry starting overflowing after fully reacting carries out Separation of Solid and Liquid, solid product after separation is through washing, after oven dry, obtain spherical nickel cobalt aluminium presoma.
5. the preparation method of a kind of rich lithium nickel cobalt alumina positive electrode according to claim 3, is characterized in that: described detergent solution is the mixed liquor of deionized water or ethanol or deionized water and ethanol.
6. the preparation method of a kind of rich lithium nickel cobalt alumina positive electrode according to claim 4, is characterized in that: described precipitant solution is NaOH precipitant solution.
7. according to the preparation method of a kind of rich lithium nickel cobalt alumina positive electrode described in claim 5 or 6, it is characterized in that: in described step 3 mixed process, add covering; At least one in described covering containing element cobalt, manganese, magnesium, titanium, zirconium, fluorine, boron, aluminium.
8. the preparation method of a kind of rich lithium nickel cobalt alumina positive electrode according to claim 4, it is characterized in that: described nickel salt solution is at least one in nickel sulfate solution, nickel chloride solution, cobalt salt solution is at least one in cobalt sulfate solution, cobalt chloride solution, and aluminum salt solution is at least one in aluminum sulfate solution, liquor alumini chloridi.
9. the preparation method of a kind of rich lithium nickel cobalt alumina positive electrode according to claim 4, is characterized in that: in described step 1, nickel ion, cobalt ions, aluminum ions mol ratio are 0.75 ~ 0.85:0.1 ~ 0.2:0.03 ~ 0.07.
10. the preparation method of a kind of rich lithium nickel cobalt alumina positive electrode according to claim 3, is characterized in that: the lithium salts in described step 3 is at least one in lithium carbonate, lithium hydroxide, lithium acetate, lithium oxalate.
CN201310615074.1A 2013-11-28 2013-11-28 Lithium, nickel, cobalt, aluminum and oxygen-rich cathode material and preparation method thereof Pending CN103633308A (en)

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CN107180950A (en) * 2017-04-17 2017-09-19 张保平 A kind of ternary cathode material of lithium ion battery NCM, NCA spray drying process preparation method
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CN108298598A (en) * 2018-01-22 2018-07-20 邴玉萍 A method of reducing the residual lithium in nickel cobalt lithium aluminate cathode material surface
TWI734960B (en) * 2018-03-20 2021-08-01 美商飛翼新能源公司 Nickel-cobalt-aluminum ternary lithium ion battery cathode material, preparation method and application thereof, and lithium ion battery
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