Structural and Electronic Features of Sb-Based Electrode Materials: ~(121)Sb Moessbauer Spectrometry

摘要

Lithium insertion mechanisms in two antimony based compounds: CoSb_3 and CoSb have been studied by means of ~(121)Sb Moessbauer spectrometry. Structural and electronic modifications induced by insertion of lithium have been characterised for different depths of discharge. In all cases the insertion mechanisms can be described from several steps. In the first step antimony is partially dispersed in the metallic matrix with amorphisation of the electrode material and in a second step we can observe the alloy forming (Li_3Sb). However this amorphous alloy remains in interaction with the matrix allowing then a good reversibility.