COMPOSITE NEGATIVE ELECTRODE MATERIAL, PRODUCTION METHOD THEREOF, NEGATIVE ELECTRODE AND LITHIUM-ION BATTERY

摘要

The invention relates to a negative electrode material, a method of producing said material, a negative electrode and a lithium-ion battery comprising said material. The inventive material comprises an active phase comprising a material M based on Al, Si, Sn, Sb or a mixture thereof and a support phase comprising a material X_aY_bO_c, wherein: O is an oxygen; Y is a cation with a degree of oxidation (m) of 3, 4, 5 or 6; X is a cation with a degree of oxidation (d) of 1, 2, 3, 4 or 5, whereby X ensures the electroneutrality of X_aY_bO_c; and c is such that 2 = c = 10; b is such that 1 = b = 4; and a = (2c-bm)/d. According to the invention, a mixed composition interface exists between material X_aY_bO_c and active phase M, said interface comprising elements M, X, Y and O. For example, X_aY_bO_c can be BPO₄. The inventive production method comprises the following steps consisting in: subjecting a mixture of oxides of X and Y to a first thermal treatment, in order to obtain material XYO₄; cooling and subsequently grinding the material obtained; mixing the ground material with M; subjecting the mixture thus obtained to a second thermal treatment, in order to obtain the inventive material; and cooling said material.