A positive electrode active material contains a lithium composite oxide and a covering material. The lithium composite oxide has a crystal structure that belongs to space group Fd-3m. The ration I.sub.(111)/I.sub.(400) of a first integrated intensity I.sub.(111) of a first peak corresponding to a (111) plane to a second integrated intensity I.sub.(400) of a second peak corresponding to a (400) plane in an XRD pattern of the lithium composite oxide satisfies 0.05≤I.sub.(111)/I.sub.(400)≤0.90. The covering material has an electron conductivity of 10.sup.6 S/m or less.

Disclosed is a process for coating onto a substrate, including preparing a precursor having a general formula Q.sub.m/nMO.sub.xF.sub.y by a reaction M(OH).sub.x+yHF+m/nQ(OH).sub.n.fwdarw.Q.sup.n+.sub.m/n(MO.sub.xF.sub.y).sup.m−, wherein Q is an onium ion, selected from quaternary alkyl ammonium, quaternary alkyl phosphonium and trialkylsulfonium; M is a metal capable of forming an oxofluorometallate, where M may further comprise one or more additional metal, metalloid, and one or more of phosphorus (P), sulfur (S) and selenium (Se), iodine (I), and arsenic (As) or a combination thereof, and x>0, y>0, m≥1, n≥1; combining the precursor with a lithium ion source and with the substrate, and mixing to form a coating composition comprising a lithium oxofluorometallate having a general formula Li.sub.mMO.sub.xF.sub.y on the substrate. Further disclosed is a core-shell electrode active material including a core capable of intercalating and deintercalating lithium coated with the lithium oxofluorometallate having the general formula Li.sub.mMO.sub.xF.sub.y.

Disclosed is a process for coating onto a substrate, including preparing a precursor having a general formula Q.sub.m/nMO.sub.xF.sub.y by a reaction M(OH).sub.x+yHF+m/nQ(OH).sub.n.fwdarw.Q.sup.n+.sub.m/n(MO.sub.xF.sub.y).sup.m−, wherein Q is an onium ion, selected from quaternary alkyl ammonium, quaternary alkyl phosphonium and trialkylsulfonium; M is a metal capable of forming an oxofluorometallate, where M may further comprise one or more additional metal, metalloid, and one or more of phosphorus (P), sulfur (S) and selenium (Se), iodine (I), and arsenic (As) or a combination thereof, and x>0, y>0, m≥1, n≥1; combining the precursor with a lithium ion source and with the substrate, and mixing to form a coating composition comprising a lithium oxofluorometallate having a general formula Li.sub.mMO.sub.xF.sub.y on the substrate. Further disclosed is a core-shell electrode active material including a core capable of intercalating and deintercalating lithium coated with the lithium oxofluorometallate having the general formula Li.sub.mMO.sub.xF.sub.y.

Methods of manufacturing cathode active materials, including preparing a solution of a hygroscopic species and a reactive oxygen species, heating the solution at a temperature that is less than about 400° C. for a time sufficient for a precipitate of the cathode active material to form, and collecting the cathode active material. The cathode active materials can be used to prepare cathodes that evolve little or no oxygen during operation. The cathodes can be economically incorporated into batteries that can provide high energy density.

Methods of manufacturing cathode active materials, including preparing a solution of a hygroscopic species and a reactive oxygen species, heating the solution at a temperature that is less than about 400° C. for a time sufficient for a precipitate of the cathode active material to form, and collecting the cathode active material. The cathode active materials can be used to prepare cathodes that evolve little or no oxygen during operation. The cathodes can be economically incorporated into batteries that can provide high energy density.

A nonaqueous electrolyte solution according to one embodiment of the present disclosure contains a lithium salt and a nonaqueous solvent; the nonaqueous solvent contains fluoroethylene carbonate and a chain carboxylic acid ester having a dielectric constant of 6.0 or more; the lithium salt contains LiPO.sub.2F.sub.2 and LiSO.sub.3F; and the respective concentrations of LiPO.sub.2F.sub.2 and LiSO.sub.3F in the non-aqueous solvent are 0.15 mol/L or more.

A nonaqueous electrolyte solution according to one embodiment of the present disclosure contains a lithium salt and a nonaqueous solvent; the nonaqueous solvent contains fluoroethylene carbonate and a chain carboxylic acid ester having a dielectric constant of 6.0 or more; the lithium salt contains LiPO.sub.2F.sub.2 and LiSO.sub.3F; and the respective concentrations of LiPO.sub.2F.sub.2 and LiSO.sub.3F in the non-aqueous solvent are 0.15 mol/L or more.

A method for manufacturing an electrochemical device that may be selected from the group consisting of: lithium ion batteries with a capacity greater than 1 mAh, capacitors, supercapacitors, resistors, inductors, transistors, photovoltaic cells, fuel cells, implementing a method for manufacturing an assembly comprising a porous electrode and a porous separator comprising a porous layer deposited on a substrate having a porosity comprised between 20% and 60% by volume, and pores with an average diameter of less than 50 nm.

A process to prepare an electrode for an electrochemical storage device by spraying an aqueous slurry composition comprising water, xanthan gum, a source of conducting carbon particles and an active material on an electrode base. The slurry may be made by first mixing solid xanthan gum with the conducting carbon particles and the active material and secondly adding water to the resulting mixture. Alternatively the slurry is obtained by mixing solid xanthan gum with a carbon-based active material and adding water to the resulting mixture obtained.

A process to prepare an electrode for an electrochemical storage device by spraying an aqueous slurry composition comprising water, xanthan gum, a source of conducting carbon particles and an active material on an electrode base. The slurry may be made by first mixing solid xanthan gum with the conducting carbon particles and the active material and secondly adding water to the resulting mixture. Alternatively the slurry is obtained by mixing solid xanthan gum with a carbon-based active material and adding water to the resulting mixture obtained.