9 results about "Lithium tungstate" patented technology

This invention relates to a polymer-based composite solid-state electrolyte, its preparation method, and a lithium solid-state battery. By weight, the polymer-based composite solid-state electrolyte comprises 5-15 parts of polymer, 5-15 parts of lithium salt, and 0.5-2.5 parts of composite filler; the composite filler includes barium titanate, with lithium tungstate coated on its surface. The polymer-based composite solid-state electrolyte of this invention exhibits high ionic conductivity and electrochemical stability, with an ionic conductivity as high as 2.86 mS / cm and an electrochemical stability window of 5.4 V. Simultaneously, the interface between the polymer-based composite solid-state electrolyte and the electrode is more stable, resulting in excellent cycle performance.

The application relates to the technical field of battery diaphragm, and discloses a lithium ion battery diaphragm with high viscosity and high safety, which is prepared from the following components in parts by weight: 15-20 parts of polyolefin, 80-85 parts of pore-forming agent and 2-4 parts of filler; the viscosity average molecular weight of the polyolefin is 1-4 million; the raw material of the filler comprises component A and component B in a mass ratio of 1:19-19:1; the component A comprises barium stearate; and the component B comprises one or more of lithium molybdate, lithium tungstate and lithium tantalate. Through the technical scheme, the problem of low strength of the lithium battery diaphragm in the related art is solved.

This invention belongs to the field of cathode materials, and provides a ternary cathode material, its preparation method, and a battery. The tungsten content of the ternary cathode material provided by this invention gradually decreases along a direction perpendicular to the surface of the ternary cathode material towards the interior, and the tungsten element in the ternary cathode material is mainly distributed within a depth range of 100 nm. The tungsten element material on the outer surface of the ternary active material includes tungsten oxide and lithium tungstate. The formed lithium tungstate consumes the residual lithium on the surface of the ternary active material, reducing the residual lithium content on the surface of the ternary cathode material. In the preparation method of the ternary cathode material provided by this invention, tungsten chloride with a low melting point is deposited on the surface of the ternary active material, and then the tungsten chloride is oxidized to tungsten oxide using an oxidation reaction to obtain the ternary cathode material. This reduces heat consumption while ensuring that the tungsten element is uniformly distributed on the surface of the ternary cathode material, thereby obtaining a ternary cathode material with high compressive strength, low surface residual lithium content, and good cycle performance.

The invention discloses a ternary positive electrode material precisely coated with a bifunctional material and a preparation method of the ternary positive electrode material, and belongs to the field of lithium ion batteries. The preparation method comprises the following steps: step 1) adopting a sol-gel method to obtain LiAl (WO4) 2 powder; and 2) uniformly dispersing LiAl (WO4) 2 powder, Co (OH) 2 and the ternary positive electrode material Lix (NiaCobMnc) O2 to obtain a mixture, and sintering the mixture to obtain the ternary positive electrode material accurately coated with the bifunctional material, and 3) crushing the ternary positive electrode material precisely coated with the bifunctional material to obtain the ternary positive electrode material. According to the invention, lithium aluminum tungstate is coated at a relatively low temperature during one-time sintering, and cobaltous hydroxide is coated at a relatively high temperature, so that the cycling stability and safety of the ternary positive electrode material under high voltage can be improved, and meanwhile, the ionic conductivity of the ternary positive electrode material can be improved, so that the charge-discharge performance of the battery is improved.

The invention relates to a polymer-based composite solid electrolyte, a preparation method and a lithium solid-state battery. The polymer-based composite solid electrolyte is prepared from the following components in parts by mass: 5 to 15 parts of polymer, 5 to 15 parts of lithium salt and 0.5 to 2.5 parts of composite filler, the composite filler comprises barium titanate, and the surface of the barium titanate is coated with lithium tungstate. The polymer-based composite solid electrolyte disclosed by the invention has relatively high ionic conductivity and electrochemical stability, the ionic conductivity of the polymer-based composite solid electrolyte is up to 2.86 mS / cm, and an electrochemical stability window is up to 5.4 V. Meanwhile, the interface between the polymer-based composite solid electrolyte and the electrode is more stable, and the cycle performance is excellent.

The invention provides a lithium nickel cobalt aluminate positive electrode material and a preparation method and application thereof, and the preparation method comprises the following steps: mixing and sintering a lithium nickel cobalt aluminate primary sintering material and a cobalt source to obtain a secondary sintering material; and mixing and sintering a tungsten source, a lithium source and the secondary sintering material to obtain the nickel cobalt lithium aluminate positive electrode material. According to the preparation method disclosed by the invention, a fast ion conductor layer is formed by firstly coating a cobalt source and then coating a tungsten source and a lithium source, and meanwhile, the cobalt source and the lithium source in secondary coating form a lithium cobalt oxide coating layer, so that a surface layered structure of the positive electrode material is reconstructed, and a lithium cobalt oxide coating layer and a lithium tungstate coating layer are generated on the surface of nickel cobalt lithium aluminate; the interface characteristic of the positive electrode material is improved, and the cycle performance of the material is improved while the discharge capacity is improved.

This invention provides a method for estimating the amount of coating present on the surface of a positive electrode active material. [Solution] An estimation method comprising: obtaining the lithium content (Li) and the content of metals other than lithium in the positive electrode active material (Me) in the battery, assuming that the lithium content derived from the positive electrode active material is 1 mole, and calculating the ratio of Li to Me; obtaining the amount of Ni and Li mixed in the positive electrode active material and calculating the molar ratio of the mixing amounts; obtaining the lithium carbonate content and calculating the molar ratio of lithium derived from lithium carbonate; obtaining the lithium hydroxide content and calculating the molar ratio of lithium derived from lithium hydroxide; and calculating the molar ratio of lithium derived from lithium tungstate using the following formula (1). [Li / Me]-(1-[Ni mixing])=[Li mixing]+[Li2CO3]+[LiOH]+[Lithium tungstate] Equation (1)

The present application relates to the field of battery technology and provides a secondary battery and its preparation method, energy storage system and electrical equipment, which are at least beneficial to improving the cycle performance of the secondary battery. The method includes: preparing a positive electrode sheet, the preparation steps including: preparing a composite lithium supplement material including boron-doped graphene, lithium tantalate and lithium tungstate by freeze-drying; preparing boron-lithium iron phosphate by electrostatic self-assembly; mixing the composite lithium supplement material, boron-lithium iron phosphate, conductive agent and adhesive in a mass ratio of (1.5~2.2): (93.8~94.5): (0.8~1.2): (1.7~2.1) to obtain a positive electrode slurry; applying the positive electrode slurry to the surface of the positive electrode current collector and drying it to obtain a positive electrode sheet; providing a negative electrode sheet and a separator, winding the positive electrode sheet, separator and negative electrode sheet or stacking them, and then placing them in a shell, and injecting electrolyte into the shell to obtain a secondary battery.

The invention provides doped lithium tungstate as well as a preparation method and application thereof. The preparation method of the doped lithium tungstate comprises the following steps: mixing a tungsten source and a lithium source in water, adding a doping agent to obtain slurry, grinding the slurry in an ice-water bath, carrying out spray drying on the slurry to obtain powder, sintering the powder, and crushing to obtain the doped lithium tungstate LixWyMzO4. According to the technical scheme, low-energy-consumption preparation of lithium tungstate is realized, and the product has uniform nanoscale particle size distribution and controllable doped element content. According to the method, the problems of particle aggregation, high energy consumption and uneven doping in the traditional process are effectively solved, the obtained material can be used as an efficient modifier of a ternary positive electrode, and by improving the uniformity of a coating layer and the conductivity of bulk phase ions, the initial DCR of a battery is improved, and the first efficiency and the charge-discharge capacity of the battery are improved.