3 results about "Lithium tungstate" patented technology

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.

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.

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)