Negative Electrode Composite Material, Production Method, Negative Electrode and Lithium-Ion Battery

摘要

This invention relates to a negative electrode material, a method for producing this material, and to a negative electrode and a lithium-ion battery comprising this material. The material of the invention comprises an active phase consisting of a material M based on Al, Si, Sn, Sb or a mixture thereof, and a support phase consisting of a material X_aY_bO_c, where: O is an oxygen; Y is a cation with oxidation degree m=3, 4, 5 or 6; X is a cation with oxidation degree d=1, 2, 3, 4 or 5, X ensuring the electroneutrality of X_aY_bO_c; and where: c is such that 2<=c<=10; b is such that 1<=B<=4; AND A=(2C-bm)/d. An interface of mixed composition exists between the X_aY_bO_c material and the active phase M, the said interface consisting of the elements M, X, Y and O. X_aY_bO_c may be for example BPO₄. The production method comprises a first heat treatment of a mixture of oxides of X and Y to obtain a material XYO₄; a cooling followed by a grinding of the material obtained; a mixing of the ground material with M; a second heat treatment of the mixture obtained to obtain the said material of the invention; and a cooling of the said material.