CN108832121B - High-nickel positive electrode material and preparation method thereof - Google Patents
High-nickel positive electrode material and preparation method thereof Download PDFInfo
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- H01M4/48—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides
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- 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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- 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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Abstract
The invention relates to a high-nickel anode material and a preparation method thereof, wherein the anode material is made of LiNi with a general formula0.25aCr2‑0.75aX1‑ 0.5aMo0.4aMn1.5‑0.2aO4The X element is at least one of Ti, Ba, Al, Mn and Ge, wherein 0<a<2. The positive electrode material has high wear resistance and high temperature resistance, and the surface of the positive electrode material is provided with particles matched with large and small particles, so that the compaction density of the material is improved.
Description
Technical Field
The invention belongs to the technical field of lithium battery equipment, and particularly relates to a high-nickel positive electrode material and a preparation method thereof.
Background
Along with the development of social economy, people have higher and higher requirements on the performance of mobile power supplies, and the matching power supplies of various portable electronic products develop towards high specific energy, high power, long storage life and high safety. Lithium primary batteries are widely used in various civil and military fields such as sensors, cameras, cardiac pacemakers, and airplanes because of their excellent performance. Currently, common lithium primary batteries include lithium manganese dioxide batteries, lithium thionyl chloride batteries, lithium sulfur dioxide batteries, lithium fluorine batteries, lithium iron batteries, and the like. Among them, the lithium manganese dioxide battery is most widely used, and has the advantages of high discharge voltage, smooth discharge, low cost of active materials, and the like, but the specific energy is lower; the carbon fluoride is the highest theoretical specific energy in the positive electrode material of the lithium primary battery, the practical specific energy of the lithium fluorine battery can reach 250-800 Wh/kg, but the practicability of the lithium fluorine battery is limited due to the high cost of the carbon fluoride material, the low-temperature performance of the battery and the non-ideal high-current working performance of the battery.
The main constituent materials of the lithium ion battery include electrolyte, isolating material, anode and cathode materials and the like. The positive electrode material occupies a large proportion (the mass ratio of the positive electrode material to the negative electrode material is 3:1-4:1), because the performance of the positive electrode material directly influences the performance of the lithium ion battery, the cost directly determines the cost of the battery. However, the particle size of the surface of the anode material of the existing lithium battery is consistent and loose, and the anode material is easy to absorb water; the high temperature resistance and the wear resistance are poor.
Disclosure of Invention
The invention aims to solve the problems and provide a high-nickel cathode material and a preparation method thereof, wherein the high-nickel cathode material has high wear resistance and high temperature resistance, and particles matched with large and small particles are arranged on the surface of the cathode material, so that the compaction density of the material is improved.
The invention realizes the purpose through the following technical scheme:
a high-nickel anode material is prepared from LiNi0.25aCr2-0.75aX1-0.5aMo0.4aMn1.5-0.2aO4The X element is at least one of Ti, Ba, Al, Mn and Ge, and the content is 0<a<2。
A preparation method of a high-nickel cathode material comprises the following steps:
a) preparing a precursor, namely mixing a nickel salt solution, a cobalt salt solution and a manganese salt solution, wherein the sum of the concentrations of three ions of nickel, cobalt and manganese in the mixed solution is 0.5-2.0 mol/L, adding a chromium salt solution and a molybdenum salt solution into the mixed solution, wherein the concentrations of chromium and molybdenum ions are 0.01-0.02 mol/L, adding a complexing agent solution, a precipitator solution and the mixed solution into a reaction kettle in a concurrent flow manner, heating and stirring for precipitation reaction, starting solid-liquid separation on overflowed slurry after full reaction, and washing and drying the separated solid product;
b) calcining the synthesized precursor for the first time, introducing non-reducing gas, cooling, crushing, calcining for the second time, simultaneously introducing non-reducing gas, cooling and grinding;
c) and (3) mixing the ground mixture and a lithium salt according to the molar ratio of the metal cations to the Li ions of 1: 1.3-1.5, uniformly mixing, sintering, introducing non-reducing gas in the sintering process, cooling along with a furnace after sintering, and then crushing and sieving.
d) Adding the substances obtained in the step, a detergent solution and a coating solution into a mixer for mixing for 0.3-1.5h, performing suction filtration on a solid-liquid mixture after mixing, drying, sieving and mixing;
e) and sintering the product obtained after sieving and mixing in the steps at the sintering temperature of 500-900 ℃ for 6-20 h, cooling the product along with the furnace after sintering is finished, and sieving the product to obtain the lithium-rich high-nickel cathode material.
As a further optimized technical scheme of the invention, the chromium salt in the step a is chromium sulfate; the molybdenum salt is molybdenum nitrate.
As a further optimized technical scheme of the invention, the temperature of the first calcination in the step b is 200-280 ℃, the calcination time is 2-3 h, the temperature of the second calcination is 500-700 ℃, and the calcination time is 3-5 h.
As a further optimized technical scheme of the invention, the sintering temperature in the step c is 700-900 ℃, and the sintering time is 9-24 h.
As a further optimized technical scheme of the invention, the detergent solution in the step d is at least one of deionized water, ethanol or a mixed solution thereof, the coating agent contains at least one of Ti, Ba, Al, Mn and Ge, and the content of the coating agent is 0.02-0.04%.
The invention has the beneficial effects that:
1) the wear resistance and the high temperature resistance of the anode material are improved by adding the chromium salt solution and the molybdenum salt solution under the condition of preparing the precursor;
2) according to the invention, the precursor is subjected to twice calcination treatments, and is crushed after the first calcination treatment, so that the moisture of the precursor is removed more thoroughly, and the particles are finer and are convenient for the next reaction by grinding after the second calcination treatment;
3) according to the invention, the high nickel ion product is treated by the coating agent, so that particles matched with large and small particles are arranged on the surface of the anode material, and the compaction density of the material is improved.
Drawings
FIG. 1 is an SEM image of a product of example one of the present invention.
Detailed Description
The present application will now be described in further detail with reference to the drawings, it should be noted that the following detailed description is given for illustrative purposes only and is not to be construed as limiting the scope of the present application, as those skilled in the art will be able to make numerous insubstantial modifications and adaptations to the present application based on the above disclosure.
Example 1
a) Preparing a nickel-cobalt-manganese precursor: uniformly mixing a nickel sulfate solution, a cobalt sulfate solution and a manganese sulfate solution which are used as raw materials, wherein the concentration of metal ions in the mixed solution is 1.0mol/L, adding a chromium sulfate solution and a molybdenum nitrate solution into the mixed solution, wherein the concentration of chromium ions and molybdenum ions is 0.01mol/L, adding a complexing agent solution, a NaOH precipitator solution and the mixed solution into a reaction kettle filled with a base solution in a concurrent flow manner, heating and stirring for precipitation reaction, starting solid-liquid separation on overflowed slurry after full reaction, and washing and drying the separated solid product to obtain a spherical nickel-cobalt-manganese precursor;
b) calcining the precursor of the lithium-rich high-nickel cathode material obtained in the step for the first time at the temperature of 200 ℃ for 3 hours, introducing non-reducing gas, cooling, crushing, calcining for the second time at the temperature of 500 ℃ for 5 hours, introducing non-reducing gas, cooling, and grinding;
c) and (3) mixing the mixture sieved in the step with a lithium salt according to the molar ratio of metal cations to Li ions of 1: 1.3, uniformly mixing, sintering at 750 ℃ for 24 hours, continuously introducing air into the furnace during the sintering, cooling along with the furnace after the sintering is finished, crushing and sieving to obtain an intermediate product of the lithium-rich high-nickel cathode material;
d) adding the product obtained in the step, deionized water and a barium nitrate coating agent solution into a high-speed mixer, mixing for 1.5h, performing suction filtration and drying on a solid-liquid mixture after mixing, and sieving;
e) and sintering the product obtained after sieving and mixing in the steps at the sintering temperature of 500 ℃ for 20 hours, cooling the product in a furnace after sintering, and sieving the product to obtain the lithium-rich high-nickel cathode material.
Through inspection, the tap density of the lithium-rich high-nickel cathode material prepared by the method of the embodiment is 2.56g/cm3Has higher wear resistance and high temperature resistance,the SEM spectrum of the product is shown in figure 1.
Example 2
a) Preparing a nickel-cobalt-manganese precursor: uniformly mixing a nickel sulfate solution, a cobalt sulfate solution and a manganese sulfate solution which are used as raw materials, wherein the concentration of metal ions in the mixed solution is 2.0mol/L, adding a chromium sulfate solution and a molybdenum nitrate solution into the mixed solution, wherein the concentration of chromium ions and molybdenum ions is 0.02mol/L, adding a complexing agent solution, a NaOH precipitator solution and the mixed solution into a reaction kettle filled with a base solution in a concurrent flow manner, heating and stirring for precipitation reaction, starting solid-liquid separation on overflowed slurry after full reaction, and washing and drying the separated solid product to obtain a spherical nickel-cobalt-manganese precursor;
b) calcining the precursor of the lithium-rich high-nickel cathode material obtained in the step for the first time at 280 ℃ for 2h, introducing non-reducing gas, cooling, crushing, calcining for the second time at 3h and 700 ℃, introducing non-reducing gas, cooling, and grinding;
c) and (3) mixing the mixture sieved in the step with a lithium salt according to the molar ratio of metal cations to Li ions of 1: 1.5, uniformly mixing, sintering at 900 ℃ for 9h, continuously introducing air into the furnace during the sintering, cooling along with the furnace after the sintering is finished, crushing and sieving to obtain an intermediate product of the lithium-rich high-nickel cathode material;
d) adding the product obtained in the step, deionized water and a chromium nitrate coating agent solution into a high-speed mixer, mixing for 0.3h, filtering, drying and sieving a solid-liquid mixture after mixing;
e) and sintering the product obtained after sieving and mixing in the steps at the sintering temperature of 900 ℃ for 10 hours, cooling the product in a furnace after sintering, and sieving the product to obtain the lithium-rich high-nickel cathode material.
Through inspection, the tap density of the lithium-rich high-nickel cathode material prepared by the method of the embodiment is 2.62g/cm3Has high wear resistance and high temperature resistance.
The above-mentioned embodiments only express several embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the present invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention.
Claims (4)
1. A preparation method of a high-nickel anode material is characterized in that the anode material is made of LiNi with a general formula0.25aCr2- 0.75aX1-0.5aMo0.4aMn1.5-0.2aO4The X element is at least one of Ti, Ba, Al, Mn and Ge, wherein 0<a<2；
The preparation method comprises the following steps:
a) preparing a precursor, namely mixing a nickel salt solution, a cobalt salt solution and a manganese salt solution, wherein the sum of the concentrations of three ions of nickel, cobalt and manganese in the mixed solution is 0.5-2.0 mol/L, adding a chromium salt solution and a molybdenum salt solution into the mixed solution to prepare a mixed solution, wherein the concentration of the ions of chromium and molybdenum is 0.01-0.02 mol/L, adding a complexing agent solution, a precipitator solution and the mixed solution into a reaction kettle in a concurrent flow manner, heating and stirring for precipitation reaction, carrying out solid-liquid separation on overflowed slurry after full reaction, and washing and drying the separated solid product;
b) calcining the synthesized precursor for the first time, introducing non-reducing gas, cooling, crushing, calcining for the second time after crushing, introducing non-reducing gas, cooling, and grinding, wherein the temperature of the first calcining is 200-280 ℃, the calcining time is 2-3 h, the temperature of the second calcining is 500-700 ℃, and the calcining time is 3-5 h;
c) and (3) mixing the ground mixture and a lithium salt according to the molar ratio of the metal cations to the Li ions of 1: 1.3-1.5, uniformly mixing, sintering, introducing non-reducing gas in the sintering process, cooling along with a furnace after sintering, and then crushing and sieving;
d) c, adding the substance obtained in the step c, a detergent solution and a coating solution into a mixer for mixing for 0.3-1.5h, performing suction filtration on a solid-liquid mixture after mixing, drying, sieving and mixing;
e) and d, sintering the product obtained after sieving and mixing in the step d at the sintering temperature of 500-900 ℃ for 6-20 h, cooling the product along with the furnace after sintering is finished, and sieving the product to obtain the required cathode material.
2. The method for preparing a high nickel positive electrode material according to claim 1, wherein: in the step a, the chromium salt is chromium sulfate; the molybdenum salt is molybdenum nitrate.
3. The method for preparing a high nickel positive electrode material according to claim 1, wherein: the sintering temperature in the step c is 700-900 ℃, and the sintering time is 9-24 h.
4. The method for preparing a high nickel positive electrode material according to claim 1, wherein: the detergent solution is at least one of deionized water, ethanol or a mixed solution thereof, the coating solution contains at least one of Ti, Ba, Al, Mn and Ge, and the content of the coating solution is 0.02-0.04%.
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| CN103022476A (en) * | 2012-12-24 | 2013-04-03 | 湖南长远锂科有限公司 | Preparation method of high-nickel-content anode material for lithium ion battery |
| JP2014075177A (en) * | 2011-01-27 | 2014-04-24 | Asahi Glass Co Ltd | Positive electrode active material for lithium ion secondary battery and method for manufacturing the same |
| CN103825016A (en) * | 2014-02-13 | 2014-05-28 | 宁波金和新材料股份有限公司 | Nickelic cathode material rich in lithium and preparation method thereof |
| CN103956472A (en) * | 2014-05-04 | 2014-07-30 | 张萍 | Preparation method of multi-element cathode material covered with titanium oxide |
| CN107394197A (en) * | 2017-07-18 | 2017-11-24 | 宁波富理电池材料科技有限公司 | A kind of positive electrode, its preparation method and lithium ion battery |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN101626080A (en) * | 2008-10-17 | 2010-01-13 | 成都晶元新材料技术有限公司 | Nickel-cobalt-manganese multiplex doped lithium ion battery anode material and preparation material thereof |
| JP2014075177A (en) * | 2011-01-27 | 2014-04-24 | Asahi Glass Co Ltd | Positive electrode active material for lithium ion secondary battery and method for manufacturing the same |
| CN103022476A (en) * | 2012-12-24 | 2013-04-03 | 湖南长远锂科有限公司 | Preparation method of high-nickel-content anode material for lithium ion battery |
| CN103825016A (en) * | 2014-02-13 | 2014-05-28 | 宁波金和新材料股份有限公司 | Nickelic cathode material rich in lithium and preparation method thereof |
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