30results about How to "Reduce the amount of residual alkali" patented technology

The invention discloses an aluminum oxide coated nickel-cobalt-manganese ternary positive electrode material, a preparation method and application thereof. The preparation method of the material comprises the following steps: (1) dripping aluminum nitrate into ammonium hydroxide, reacting until precipitates are not increased any longer, adding citric acid and nitric acid, and preparing an AlOOH sol; (2) mixing a nickel-cobalt-manganese precursor and a lithium source uniformly, and sintering to obtain a nickel-cobalt-manganese ternary material; and (3) putting the nickel-cobalt-manganese ternary material into the AlOOH sol, carrying out calcinations after drying, and finally obtaining the aluminum oxide coated nickel-cobalt-manganese ternary positive electrode material. An aluminum oxide coating layer is coated on the surface of the nickel-cobalt-manganese ternary material, so that the amount of residual alkali on the surface of the material is reduced, a side reaction between the material and an electrolyte is inhibited effectively, and the safety performance of a battery is improved; moreover, in the battery prepared from the material, an Li-Al-Co-O protective layer is formed by the aluminum oxide coating layer during working on the surface of the material, and the protective layer can resist the corrosion of HF on active materials, so that the cycle performance of the batteryis improved.

The invention provides a modified low residual alkali type high nickel ternary cathode material and a preparation method and application thereof. According to the preparation method, a high nickel ternary cathode material and hydrogen phosphate are dispersed in a solvent uniformly, then an obtained mixed solution is stoved, then a stoved product is sintered, so as to enable residual alkali on thesurface of the high nickel ternary cathode material and hydrogen phosphate to react to generate phosphate. The process shows how the modified low residual alkali type high nickel ternary cathode material is produced. Remarkable reduction of residual alkali and pH of the modified low residual alkali type high nickel ternary cathode material help prevent residual alkali from directly contacting withelectrolyte to produce side effects, and cause high ionic conductivity between reaction interfaces of the modified low residual alkali type high nickel ternary cathode material and the electrolyte, thereby reducing impedance; further, the rate performance of the material is improved remarkably; and high temperature cycle performance of the material is improved remarkably.

The invention provides a ternary positive electrode material, a preparation method thereof and a lithium ion battery. The ternary positive electrode material is mainly composed of a high-nickel ternary material core and a cobalt borate coating layer. The preparation method comprises the steps of 1) mixing a boron source and a cobalt source, and sintering in a protective atmosphere to obtain cobaltborate; and 2) mixing cobalt borate with the high-nickel ternary material, and heating in an oxidizing atmosphere to obtain the ternary positive electrode material. According to the ternary positiveelectrode material provided by the invention, the high-nickel ternary material core, the cobalt borate coating layer and the lithium cobalt borate positioned between the high-nickel ternary material core and the cobalt borate coating layer are matched with one another, so that the ternary positive electrode material is low in residual alkali content and good in rate discharge capacity and cycle performance. The preparation method provided by the invention is short in process, simple to operate and easy for industrial large-scale production.

The invention especially discloses a preparation method for a lithium metatitanate-coated nickel-cobalt-lithium aluminate positive electrode material, belonging to the field of positive electrode materials of lithium ion batteries. The preparation method for the lithium metatitanate-coated nickel-cobalt-lithium aluminate positive electrode material is characterized by comprising the following steps: adding titanium dioxide and nickel-cobalt-lithium aluminate powder into a coating device and carrying out sufficient dispersion, adsorption and recombination so as to obtain solid powder; and putting the solid powder into a muffle furnace, carrying out heating, roasting the solid powder in an air atmosphere and then carrying out natural cooling to room temperature so as to obtain lithium metatitanate-coated nickel-cobalt-lithium aluminate. According to the invention, lithium metatitanate is used for surface coating and used as a conductor material for Li<+>, so intercalation and deintercalation of Li<+> can be better realized, and the cycle performance and rate performance of the material are improved; and through coating with lithium metatitanate, humidity sensitivity of NCA is reduced, direct contact between the electrode material and an organic electrolyte is decreased, so the structural stability of NCA is further improved and security of the material is enhanced.

The invention provides a ternary positive electrode material, a preparation method thereof and a lithium ion battery. The ternary positive electrode material comprises a core and a composite coating layer coating the core, the core is a high-nickel ternary material, and the composite coating layer comprises a boron-containing compound and a phosphorus-containing compound. The method comprises the following steps: mixing a boron source, a phosphorus source and a high-nickel ternary material, and sintering in an oxidizing atmosphere to obtain the ternary positive electrode material. According to the ternary positive electrode material provided by the invention, through the high-nickel ternary material core and the composite coating layer including the boron-containing compound and the phosphorus-containing compound, the residual alkali amount is low, and the rate discharge capacity and the cycle performance are good.

The invention provides a Mg-doped nickel-cobalt-aluminum ternary cathode material and a preparation method and application thereof. The Mg-doped nickel-cobalt-aluminum ternary cathode material has thechemical formula of (LiaNi1-x-yCoxAly)1-bMgbO2, with y>0, 1-x-y>0, 1</=a</=1.1, and 0<b</=0.01. The preparation method comprises: sintering a ternary cathode material precursor Ni1-x-yCoxAly(OH)2+y;adding a lithium source and a doping material into the sintering resultant, and carrying out sintering; performing tertiary sintering to obtain the target product. The Mg-doped nickel-cobalt-aluminumternary cathode material prepared herein has good cycle performance. The preparation method having the triple sintering steps has simple technicality and controllable process and facilitates industrial large-scale production.

The invention provides a doped nickel-cobalt-aluminum ternary lithium-ion battery positive electrode material as well as a preparation method and application. A chemical formula of the material is asfollows: (LiaNi1-x-yCoxAly)1-bMbO2, wherein x is greater than 0 and y is greater than 0; the 1-x-y is greater than 0; the a is greater than or equal to 1 and less than or equal to 1.1; the b is greater than 0 and less than or equal to 0.01. A preparation method of the material comprises the following steps: firstly, sintering a ternary positive electrode material precursor Ni1-x-yCoxAly(OH)2+y; then adding a sintered product into a lithium source and a doping material and sintering; finally, carrying out third-time sintering to obtain a target product. The doped nickel-cobalt-aluminum ternarylithium-ion battery positive electrode material synthesized by the preparation method provided by the invention has good circulating performance. The preparation method provided by the invention comprises three times of sintering steps and has the advantages of simple technology, controllable process and easiness for industrialized mass production.

The invention provides an Al-doping nickel-cobalt-aluminum ternary lithium ion battery positive electrode material as well as a preparation method and a purpose thereof. The material has a chemical formula of (LiaNi1-x-yCoxAly)1-bAlbO2, wherein the x is greater than 0; the y is greater than 0; 1-x-y is greater than 0; the a is greater than or equal to 1 but smaller than or equal to 1.1; the b is greater than 0 but smaller than or equal to 0.01. According to the preparation method of the material, firstly, a three-ingredient positive electrode material precursor Ni1-x-yCoxAly(OH)2+y is sintered; then, a lithium source and doping materials are added into the obtained materials after the sintering; sintering is performed; finally, the third time sintering is performed; target products are obtained. The doping nickel-cobalt-aluminum ternary lithium ion battery positive electrode material synthesized by the preparation method has excellent circulation performance. The preparation method comprises three times sintering steps; the process is simple; the process is controllable; the industrial mass production is easy.

The invention provides a composite externally-coated positive electrode material and a preparation method thereof, a positive electrode and a lithium ion battery. The composite externally-coated positive electrode material comprises positive electrode material particles, a composite coating layer is of a single-layer structure, at least part of an outer surface of the positive electrode material particle is coated with the composite coating layer, and the composite coating layer contains lithium, nickel, cobalt, manganese and boron elements. The composite externally-coated positive electrode material is advantaged in that a gas production problem is effectively improved, moreover, the composite coating layer optimizes the defects that a single coating layer is poor in conductive chemical performance, incomplete, low in capacity and first effect and the like, the firing temperature is reduced, and the residual alkali amount of a final product is reduced.

The invention discloses a lithium iron manganese phosphate coated single crystal quaternary positive electrode material, wherein the molecular formula is LiNixCoyMnzM1-x-y-zO2@(LiMnaFe1-aPO4), x is more than or equal to 0.50 and less than or equal to 0.90, y is more than or equal to 0.05 and less than or equal to 0.20, z is more than or equal to 0.05 and less than or equal to 0.30, 1-x-y-z is more than or equal to 0 and less than or equal to 0.03, a is more than or equal to 0.5 and less than or equal to 1, and the lithium iron manganese phosphate coated single crystal quaternary positive electrode material is composed of a single crystal quaternary positive electrode material and a lithium iron manganese phosphate nano coating layer coating the surface of the single crystal quaternary positive electrode material. The preparation method comprises the following steps: mixing a lithium source and a precursor to prepare a single crystal quaternary positive electrode material, mixing the single crystal quaternary positive electrode material with a coating agent lithium iron manganese phosphate, calcining, cooling, and sieving to obtain the lithium iron manganese phosphate coated single crystal quaternary positive electrode material. According to the invention, the obtained lithium iron manganese phosphate coated single crystal quaternary positive electrode material product is fine in particle, uniform in coating distribution and excellent in electrochemical performance, and the preparation method is simple to operate and easy for industrial production.

The invention relates to a lithium ion battery positive electrode material, and particularly provides a preparation method of a gradient high-nickel single-crystal ternary material. The preparation method comprises the following steps of: (1) taking nanoscale high-nickel ternary material particles as crystal nucleuses; (2) carrying out a first coprecipitation reaction on the crystal nucleuses and a first nickel-cobalt-manganese-containing solution, adding a second nickel-cobalt-manganese-containing solution into the solution after the first coprecipitation reaction is completed, carrying out a second coprecipitation reaction, and carrying out coprecipitation reactions for n times according to the method, wherein the nickel content in the first nickel-cobalt-manganese-containing solution to the nth nickel-cobalt-manganese-containing solution is reduced in a gradient manner, and the manganese content is increased in a gradient manner; and (3) mixing the product of the nth coprecipitation reaction, a lithium source and the crystal nucleuses, and calcining the mixture in an oxygen-containing atmosphere. The gradient high-nickel single-crystal ternary material prepared by adopting the method has an obvious single-crystal form, the structural strength of ternary material particles is effectively improved, the residual alkali amount on the surface of the material is reduced, and the discharge capacity and the cycle performance of a battery can be effectively improved when the gradient high-nickel single-crystal ternary material is applied to the battery.

The invention discloses a positive electrode material and a preparation method thereof, and a lithium ion battery containing the positive electrode material. The positive electrode material comprisesa ternary positive electrode material and an iridium oxide layer being coated on a surface of the ternary positive electrode material. The preparation method comprises steps of 1) carrying out primarysintering of a ternary precursor, mixing the obtained primary sintering powder with a lithium source, and carrying out secondary sintering to obtain secondary sintered powder; 2) mixing the secondarysintered powder obtained in the 1) with an iridium source, carrying out hydrothermal reaction, and carrying out solid-liquid separation after the reaction to obtain solid which is a hydrothermal product; and 3) sintering the hydrothermal product obtained in the 2) to obtain the positive electrode material. The positive electrode material is advantaged in that the positive electrode material is low in residual alkali content and good in cycle performance; when the iridium oxide is doped into the crystal structure of the ternary positive electrode material, electrochemical performance is more excellent; the preparation method is simple and easy to control, and doping of the iridium oxide into the ternary positive electrode material crystal structure can be realized by regulating and controlling preparation conditions.

The invention belongs to the technical field of lithium ion battery positive electrode materials, and particularly relates to a nickel manganese tungsten lithium ion battery positive electrode material and a preparation method thereof.The chemical formula of the nickel manganese tungsten lithium ion battery positive electrode material is LiNixMnyWzO2, and the positive electrode material is prepared through a solvothermal reaction and a high-temperature solid-phase reaction in sequence; the solvothermal reaction is that a nickel source compound, a manganese source compound and a tungsten source compound are subjected to solvothermal reaction in a water solvent containing a precipitator to prepare nickel-manganese-tungsten precursor powder; according to the high-temperature solid-phase reaction, nickel-manganese-tungsten precursor powder and a lithium source compound are subjected to ball milling and mixing, then heating sintering is conducted in the oxygen atmosphere, then heat preservation sintering is conducted, and the prepared nickel-manganese-tungsten lithium ion battery positive electrode material LiNixMnyWzO2 has excellent electrochemical activity, structural stability and safety performance.

The invention provides a preparation method of 1, 4-butanediol diglycidyl ether, and relates to the technical field of organic synthesis. According to the invention, an efficient Lewis acid catalyst is adopted in an etherification reaction stage of 1, 4-butanediol and epoxy chloropropane, then a catalyst is added through a main reaction, an aqueous alkali solution is dropwise added in a segmented mode, and negative-pressure closed-loop reflux dehydration is conducted in a segmented mode, so that the water content of a reaction system is reduced, the reaction forward process is promoted, the prepared 1, 4-butanediol diglycidyl ether product is low in hydrolytic chlorine and high in yield, the residual alkali amount and TOC of wastewater are reduced, the problems of too high residual alkali amount and high organic matter content in saline water are solved, and industrial clean production of the 1, 4-butanediol diglycidyl ether is realized; and the preparation method has the advantages of stable process, continuous production operation, avoidance of tedious solid caustic soda feeding, high safety, low raw material consumption and low production cost.