PROCESS FOR PREPARING ALLOY COMPOSITE NEGATIVE ELECTRODE MATERIAL FOR LITHIUM ION BATTERIES

摘要

The present invention relates to a process for preparing an alloy composite negative electrode material having a spherical carbon matrix structure for lithium ion batteries by spray-drying carbothermal reduction. The invention covers a process for preparing a negative electrode material for a lithium ion battery with a general formula A-M/Carbon, wherein A is a metal selected from the group consisting of Si, Sn, Sb, Ge and Al; and wherein M is different from A and is at least one element selected from the group consisting of B, Cr, Nb, Cu, Zr, Ag, Ni, Zn, Fe, Co, Mn, Sb, Zn, Ca, Mg, V, Ti, In, Al, Ge; and comprising the steps of. - providing a solution comprising an organic polymer and either chemically reducible nanometric A- and M-precursor compounds, or nanometric Si and a chemically reducible M-precursor compound, when said metal A is Si; - spray-drying said solution whereby a A- and M-precursor bearing polymer powder is obtained, and -calcining said powder in a neutral atmosphere at a temperature between 500 and 1000° C for 3 to 10 hours whereby, in this carbothermal reduction, a carbon matrix is obtained bearing homogeneously distributed A-M alloy particles.