FIELD: electrical engineering.
SUBSTANCE: invention relates to the field of electrical engineering, namely, to a silicon material used as an active material of a negative electrode of a lithium-ion secondary battery. Proposed silicon material for the active material of the negative electrode has a width of the forbidden zone in the range of more than 1.1 eV and not more than 1.7 eV and contains nanoscale crystallites of silicon. Oxygen content in said material is not more than 20 % by weight and is obtained by performing heat treatment in a non-oxidizing atmosphere.
EFFECT: secondary battery containing a negative electrode of the proposed silicon material has an increased discharge capacity and an increased cyclic life.
12 cl, 3 dwg, 7 ex, 1 tbl
