31results about How to "Reduce residual lithium" patented technology

The invention belongs to the field of battery materials, and specifically discloses a polymetallic phosphate-coated lithium cobaltate positive electrode material and a preparation method thereof. The invention creatively coats a polymetallic phosphate layer on the surface of a lithium cobaltate positive electrode material matrix to prepare The method is as follows: Add the prepared metal salt solution and polymer compound in pure water to react, then add lithium cobaltate aqueous solution after dispersion, stir and heat at the same time to form a gel; mix the gel evenly and add it to a mechanical fusion compactor The coating of the material is completed in the process; finally, the lithium cobalt oxide cathode material coated with polymetallic phosphate is obtained after rapid and efficient sintering at a lower temperature and then natural cooling with the furnace. The cladding layer on the surface of the lithium cobaltate positive electrode material of the present invention is a fast ion conductor, which can improve the rate performance of the material; it can also prevent the reaction between the electrode and the electrolyte, and slow down the capacity fading of the lithium cobaltate material; at the same time, the present invention The advanced technology can effectively reduce the amount of residual lithium in the finished product and improve its storage performance.

The invention discloses a silicon oxide-coated high-nickel precursor, a modified high-nickel material and a preparation method thereof, comprising the following steps: preparing a salt solution of nickel, cobalt and manganese into a mixed salt solution, mixing the mixed salt solution, The solution and the complexing agent solution are added to the reaction kettle protected by an inert atmosphere in a stirring state, and the stirring is continued, and the co-precipitation reaction is carried out under the specified reaction conditions. After the reaction is completed, filter, wash, and dry to obtain the nickel-cobalt-manganese hydroxide precursor body; Add the nickel hydroxide nickel cobalt manganese precursor to the pre-prepared silicon source solution, add ammonia water, stir until the nickel hydroxide nickel cobalt manganese precursor dissolves, age, filter, wash, and dry to obtain silicon oxide coating High nickel precursor. The present invention performs SiO on the high-nickel precursor by wet coating 2 Coating is conducive to the uniform dispersion of materials, so that SiO 2 It is coated on the surface of the precursor in the form of nanoparticles, thereby improving the cycle and storage performance of the modified high-nickel material.

Lithium zirconium phosphate fast ion conductor coated nickel cobalt lithium aluminate positive electrode material and preparation method thereof, the mass of the lithium zirconium phosphate fast ion conductor is 0.1-10wt%, and the lithium zirconium phosphate fast ion conductor is formed into a layer with a thickness of 5-30nm The coating layer is coated on lithium nickel cobalt aluminate; the positive electrode material is a spherical particle with a particle diameter of 5-15 μm. The preparation method includes the following steps: (1) Prepare a solution containing phosphorus source and zirconium source, add zirconium source solution in organic solvent or water, then add phosphorus source solution, stir, then add nickel-cobalt lithium aluminate, heat and stir to react , slowly evaporated to dryness, and put the obtained powder into an oven for drying; (2) Put the powder obtained in step (1) in a tube furnace for low-temperature rapid sintering. The positive electrode material of the present invention has good cycle stability and rate discharge performance; the method of the present invention can effectively reduce the problems of surface residual lithium and low cycle stability of ternary materials during conventional coating, the process cost is low, the process is simple, and it is suitable for large industrial production.

The invention provides a positive electrode lithium supplement material and its preparation method and application, the positive electrode lithium supplement material comprises Li 2‑x Ni 1‑ y m y o 2 and coated in Li 2‑x Ni 1‑y m y o 2 Surface Me m o n A cladding layer; wherein the M includes any one or a combination of at least two of Cu, Fe or V, and the Me includes any one or a combination of at least two of Ti, Al, Zr or B, the present invention The invention uses low-cost metal elements for precursor co-precipitation doping, which can replace part of Ni while reducing costs 2+ , reduce lithium-nickel mixing, and stabilize the structure during the cycle of the cell, reduce the amount of oxygen released, in the Li 2‑x Ni 1‑ y m y o 2 Me m o n The coating layer greatly reduces the amount of residual lithium in the finished product, improves processing and gas production performance, and at the same time can inhibit the dissolution of transition metals nickel, copper, and iron, and the anode damages the SEI film, thereby improving the cycle.

The present disclosure relates to a lithium hydroxide monohydrate, its preparation method and use, and lithium ion battery cathode material and lithium ion battery. The particle size of the lithium hydroxide monohydrate is 100-380 nm, and the monohydrate The content of Cu in lithium hydroxide is less than 1ppm, the content of Cr is less than 1ppm, the content of Ni is less than 2ppm, the content of Zn is less than 2ppm, and the content of Fe is less than 4ppm. The lithium hydroxide monohydrate has a low content of magnetic elements, and when used to prepare lithium-ion battery cathode materials, can improve the service life of the lithium-ion battery and reduce its self-discharge effect.

The invention discloses a method for preparing a high-capacity, high-compaction density, and high-nickel positive electrode material, which includes the following steps: step S1, mixing high-nickel precursors and nanometer metal oxides with two particle sizes at a high speed according to a certain ratio, and then Carry out the first sintering, lower the temperature, and sieve to obtain the intermediate; step S2, mix the intermediate with the grain growth accelerator and battery-grade lithium hydroxide at a high speed according to a certain ratio, and then perform the second sintering, and the sintering is completed and reduced After reaching room temperature, it is crushed and sieved to obtain a high-nickel material with a high compacted density. The present invention changes the particle size distribution of the precursor material by mixing two high-nickel precursors with different D50 according to a certain ratio, and improves the shortcoming of insufficient compaction. Low temperature pretreatment can make the additives evenly attached to the precursor, so that the doping elements are evenly distributed in the bulk phase of the product, which improves the stability and cycle performance of the material.

The invention discloses a doped nickel cobalt lithium manganate precursor, the molecular formula is Ni x co y mn z Al t (OH) 2+3t ·nWO 4 , where x+y+z=1, 0.4<x<1.0, 0<y≤0.5, 0<z≤0.5, 0<t<0.2, 0<n<0.2, Al and W are in the atomic scale in the precursor The uniform mixing on the surface, the primary particles of the precursor are regular lath-shaped and vertically loosely arranged, and the secondary particles are spherical in shape with a diameter distance not greater than 0.75. The preparation method of the doped nickel cobalt lithium manganate precursor is also disclosed. The doping elements in the precursor material of the present invention realize uniform mixing at the atomic level, which is beneficial to improving the electrochemical performance of the positive electrode material, and the secondary particles of the precursor material of the present invention do not crack during the production process, and the shape remains intact. The preparation method has a simple process flow, can stably prepare a good-quality precursor in batches, and has broad application prospects.

A positive active material for a rechargeable lithium battery includes: a first positive active material comprising secondary particles comprising at least two agglomerated primary particles, wherein at least a portion of the primary particles have radially arranged structure; and a second cathode active material having an individual structure. Both the first positive electrode active material and the second positive electrode active material may include a nickel-based positive electrode active material. Also provided are methods for preparing the positive electrode active material and a positive electrode rechargeable lithium battery including the positive electrode active material.

The invention relates to a lithium nickel cobalt manganate positive electrode material and a preparation method thereof. The preparation method comprises the following steps of preparing seed crystalby adopting a hydrothermal method; performing a coprecipitation reaction on the seed crystal to obtain an Ni<x>Co<y>Mn<1-x-y>(OH)<2>, enabling the precursor to be mixed with lithium hydroxide or lithium carbonate at a molar ratio of Li to (Ni+Co+Mn) of 1:1-1.2, and next, performing sintering treatment on the mixture to obtain an intermediate body; enabling the intermediate body to be mixed with lithium hydroxide, and next, spraying metal sol to obtain a pre-coating material; and performing secondary sintering on the pre-coating material to obtain the lithium nickel cobalt manganate positive electrode material. The lithium nickel cobalt manganate positive electrode material prepared by the preparation method has the monocrystal appearance; and the lithium ion battery adopting the positive electrode material is high in energy density which can reach as high as 300wh / kg, and the cycle life can reach 3,000 times.

The invention discloses a surface-coated ternary positive electrode material and a preparation method thereof, belonging to the technical field of lithium ion battery positive electrode materials. The present invention includes molecular formula is LiNi x co 1‑x‑y mn y o 2 particles, the LiNi x co 1‑x‑y mn y o 2 The particle surface is covered with Li 2 MTiO 4 Nanoparticles, wherein M is at least one metal element in Ni, Co, and Mn. The present invention LiNi x co 1‑x‑y mn y o 2 The basic crystal phase structure of the battery is not destroyed, but a new phase of nanoparticles is coated on the surface to form surface protection, increase the interface stability between the surface of the positive electrode material and the electrolyte, and further improve the cycle retention rate of the material. Enhanced electrochemical performance. The surface alkalinity of the cathode material of the invention is reduced, the water absorption is suppressed, and the processing performance is improved.

The invention discloses a high-voltage nickel-cobalt lithium manganate positive electrode material and a preparation method thereof. The nickel-cobalt lithium manganate positive electrode material refers to a nickel-cobalt lithium manganate dopant material coated with phosphate. The nickel-cobalt lithium manganate Lithium manganate dopant refers to nickel-cobalt lithium manganate doped with lanthanum and fluorine elements, and the phosphate is made by blending aluminum phosphate and diammonium hydrogen phosphate solution. The present invention can increase the interplanar spacing by doping lanthanum and fluorine elements to promote the migration of lithium ions and improve structural stability, and the surface of the material has better lithium ion conductivity and certain electronic conductivity characteristics by coating the surface with phosphate. It has higher delithiation state stability under high voltage. Moreover, the amount of residual lithium on the surface of the material is reduced, surface side reactions are suppressed, and the structural stability and cycle performance of the material under high voltage are significantly improved.

The invention discloses a preparation method of a single crystal ternary positive electrode material in the technical field of lithium ion batteries, which comprises mixing and ball milling lithium oxide and three oxides of nickel, cobalt and manganese in proportion; The first sintering is carried out at ℃; the product after the first sintering is then sintered at 650-780°C for the second time; finally, it is naturally cooled to room temperature to obtain a single crystal ternary cathode material. The present invention directly uses oxides as raw materials, avoiding the phenomenon of gas generation when hydroxides or carbonates are used as raw materials, thereby greatly improving the consistency of the atmosphere, the stability of heat and the cracking of structures; the present invention also By directly mixing lithium oxide with nickel, cobalt, and manganese oxides, it can be mixed evenly. The particle size of the sintered raw material is small, and the elements are evenly mixed, which provides the conditions for forming single crystal at a lower temperature.