Abstract: The invention relates to An active material for a rechargeable lithium ion battery, comprising metal (M) based particles and a silicon oxide SiOx with 0<x<2, wherein said SiOx is an intimate mixture of amorphous silicon (Si) and crystalline silicon dioxide (SiO2); wherein the metal (M) is preferably selected from the group consisting of Si, Sn, In, Al, Fe and combinations thereof.

Abstract: The invention relates to a negative electrode powder for a lithium-ion rechargeable battery comprising a mixture comprising carbon and SiOx, with 0<x<1, wherein the SiOx consists of a nanometric composite of crystalline SiO2 and amorphous Si. The method for preparing the powder comprises the steps of providing an aqueous solution comprising an anti-agglomeration agent, dispersing a silicon comprising organic compound in the aqueous solution, hydrothermally treating the aqueous solution at a temperature between 90 and 180° C. for a period of 0.5 to 24 h, preferably between 110 and 140° C. for a period of 0.5 to 4 h, thereby forming a suspension of SiO2 and Si in the aqueous solution, evaporating the solution, thereby obtaining a slurry, subjecting the slurry to a coking process whereby a solid residue is formed, calcining the solid residue at a temperature between 500 and 1300° C., preferably between 600 and 1000° C., in a non-oxidizing atmosphere.

Abstract: The invention relates to a powder comprising particles containing a core and a shell, said powder preferably having a surface area (BET) of at most 50 m2/g, said core containing silicon (Si) and said shell containing silicon oxide SiOx with 0<x?2, wherein said silicon oxide contains Sin+ cations with n being an integer from 1 to 4, wherein said silicon oxide contains Si4+ cations in an amount of at least 70 mol % from the total amount of Sin? cations.

Abstract: The invention relates to a negative electrode powder for a lithium-ion rechargeable battery comprising a mixture comprising carbon and SiOx, with 0<x<1, wherein the SiOx consists of a nanometric composite of crystalline SiO2 and amorphous Si. The method for preparing the powder comprises the steps of providing an aqueous solution comprising an anti-agglomeration agent, dispersing a silicon comprising organic compound in the aqueous solution, hydrothermally treating the aqueous solution at a temperature between 90 and 180° C. for a period of 0.5 to 24 h, preferably between 110 and 140° C. for a period of 0.5 to 4 h, thereby forming a suspension of SiO2 and Si in the aqueous solution, evaporating the solution, thereby obtaining a slurry, subjecting the slurry to a coking process whereby a solid residue is formed, calcining the solid residue at a temperature between 500 and 1300° C., preferably between 600 and 1000° C., in a non-oxidizing atmosphere.

Abstract: The invention relates to An active material for a rechargeable lithium ion battery, comprising metal (M) based particles and a silicon oxide SiOx with 0<x<2, wherein said SiOx is an intimate mixture of amorphous silicon (Si) and crystalline silicon dioxide (SiO2); wherein the metal (M) is preferably selected from the group consisting of Si, Sn, In, Al, Fe and combinations thereof.

Abstract: This invention relates to a negative electrode material for lithium-ion batteries comprising silicon and having a chemically treated or coated surface influencing the zeta potential of the surface. The active material consists of particles or particles and wires comprising a core (11) comprising silicon, wherein the particles have a positive zeta potential in an interval between pH 3.5 and 9.5, and preferably between pH 4 and 9.5. The core is either chemically treated with an amino-functional metal oxide, or the core is at least partly covered with OySiHx groups, with 1<x<3, 1<y<3, and x>y, or is covered by adsorbed inorganic nanoparticles or cationic multivalent metal ions or oxides.