Provided is a method for inhibiting extractant degradation by a diluent and an extractant input manner, the method including steps of: (a) determining and analyzing the total volume of the DSX solvent when the diluent and the extractant, which are the DSX solvents, are added in the DSX process and identifying the concentration of the extractant; (b) calculating an extractant concentration according to an amount of the diluent to be added based on the analysis value of step (a), and then adding the extractant; (c) determining the ratio between the extractants through analysis after adding the extractants; (d) adding the extractant to be needed when the ratio between extractants is out of the range; and (e) adding the diluent and analyzing the ratio between the extractants.

Provided is a positive electrode active material for a lithium ion secondary battery having favorable cycle characteristics and high capacity. A covering layer containing aluminum and a covering layer containing magnesium are provided on a superficial portion of the positive electrode active material. The covering layer containing magnesium exists in a region closer to a particle surface than the covering layer containing aluminum is. The covering layer containing aluminum can be formed by a sol-gel method using an aluminum alkoxide. The covering layer containing magnesium can be formed as follows: magnesium and fluorine are mixed as a starting material and then subjected to heating after the sol-gel step, so that magnesium is segregated.

A lithium cobalt metal oxide powder is disclosed in the present disclosure. The lithium cobalt metal oxide powder has a coating structure. The lithium cobalt metal oxide powder includes a lithium cobalt metal oxide matrix. The lithium cobalt metal oxide powder further includes a Co.sub.3O.sub.4 coating layer. A general formula of the lithium cobalt metal oxide powder is Li.sub.aCo.sub.1-x-yM.sub.xN.sub.yO.sub.2.Math.rCo.sub.3O.sub.4, wherein 0.002<r≤0.05, 1≤a≤1.1, 0<x≤0.02, 0≤y≤0.005, and a<1+3r; M is a doping element; and N is a coating element. A method for making the lithium cobalt metal oxide powder as described above and a method for determining a content of Co.sub.3O.sub.4 therein are further provided. The material made in the present disclosure has an excellent electrochemical performance.

Disclosed is a ferromagnetic element-substituted room-temperature multiferroic material having ferromagnetism and ferroelectricity at room temperature, wherein the ferromagnetic element-substituted room-temperature multiferroic material includes a compound of chemical formula 1: <chemical formula 1> (Pb.sub.1-xM.sub.x)Fe.sub.1/2Nb.sub.1/2O.sub.3. In chemical formula 1, M represents a ferromagnetic element, and x represents a number greater than 0 and smaller than 1.

The present disclosure relates to positive-electrode pre-lithiation agents. One example positive-electrode pre-lithiation agent includes a catalyst and a lithium-rich material, where the catalyst is an oxide positive-electrode active material, an intensity ratio of a crystal plane diffraction peak of the catalyst to a crystal plane diffraction peak of the catalyst is less than or equal to 2, the catalyst is configured to catalyze the lithium-rich material to decompose to release active lithium, and the lithium-rich material includes at least one of lithium oxide, lithium peroxide, lithium fluoride, lithium carbonate, lithium oxalate, or lithium acetate.

A positive electrode material, including a core and a shell layer are provided. In some embodiments, a molecular formula of the core is Li.sub.1+aNi.sub.xCo.sub.yMn.sub.1-x-yM1.sub.zO.sub.2, 0.8≤x<1.0, 0<y<0.2, 0<a<0.1, 0≤z<0.1, and M1 is selected from at least one of Al, Ta, and B; and a molecular formula of the shell layer is Li.sub.1+bCo.sub.mA1.sub.nNb.sub.1-m-nM2.sub.cO.sub.2, 0.85≤m<1.0, 0<n<0.15, 0<b<0.1, 0.001≤1-m-n≤0.02, 0≤c<0.05, and M2 is selected from at least one of W, Mo, Ti, Zr, Y, and Yb.

A more efficient and lower cost method for producing electrochemically stable, and thus safe from thermal runaway, high electrochemical capacity coated lithium nickelate is disclosed. The coated nickelate hydroxide particles are formed from a mixed metal sulfate solution (MMS) serving as the starting material that is obtained from recycled lithium ion and/or nickel metal hydride batteries. The coating of the particles includes a relatively small amount of cobalt/manganese oxide forming the surface of the nickelate particles, while the core of the particles includes a relatively large amount of nickel in relation to the weight of the coating. Battery cathode electrodes may be manufactured by using the obtained coated lithium nickelate particles as the cathode active material (CAM) in forming the battery cathodes.

Disclosed herein are doped perovskite oxides. The doped perovskite oxides may be used as a cathode material in an electrochemical cell to electrochemically generate ammonia from N.sub.2. The doped perovskite oxides may be combined with nitride compounds, for instance iron nitride, to further increase the efficiency of the ammonia production.

Provided are a sacrificial positive electrode material with a reduced gas generation amount and a method of preparing the same. The method includes calcinating a raw material mixture of lithium oxide (Li.sub.2O) and cobalt oxide (CoO) to prepare a lithium cobalt metal oxide, wherein the lithium oxide (Li.sub.2O) has an average particle size (D50) of 50 .Math.m or less, and the resulting sacrificial positive electrode material has an electrical conductivity of 1 × 10.sup.-4 S/cm or more. The method of preparing a sacrificial positive electrode material can reduce the generation of gas, particularly, oxygen (O.sub.2) gas, in an electrode assembly during charging of a battery by adjusting the electrical conductivity of the sacrificial positive electrode material within a specific range using lithium oxide that satisfies a specific size, and thus the stability and lifespan of the battery including the same can be effectively enhanced.

The invention belongs to the technical field of lithium ion battery cathode materials, and discloses a preparation method and application of nanosized lithium cobalt oxide cathode materials, comprising the following steps: mixing the carbonate solution with a dispersant, adding a cobalt salt solution to react, then aging, filtering, drying the filter residue to obtain a nano-CoCO.sub.3 powder, and then calcinating it to obtain a Co.sub.3O.sub.4 precursor; mixing the Co.sub.3O.sub.4 precursor with a lithium salt, and then sintering, cooling, pulverizing and sieving to obtain the nanosized lithium cobalt oxide cathode material. The main advantages of the present invention are that the nano-CoCO.sub.3 synthesis process is simple and easy to control, the process is short, no special temperature control is required, the pH value and other conditions are not required to be precisely controlled during the reaction process, and it is suitable for large-scale industrial production.