Phase separation and amorphisation in lithium inserted Cu-In-Sn sulfospinels: experimental and theoretical approach

Sn-119. Mossbauer spectroscopy, X-ray diffraction (XRD) and electrochemical experiments were carried out to characterise the reaction mechanism of Lit hium with spinel phases CuxInySn2S4. The electrochemical investigations hav e shown interesting reversible capacities for these materials, and their po ssible use as anode materials in lithium-ion cells. This analysis reveals a multi-phase mechanism linked to the reduction of the cations involving a s pinel to rocksalt transformation followed by a structural breakdown. Densit y functional calculations by the linearised augmented plane wave (LAPW) met hod give a good interpretation of experimental results for crystalline phas es. (C) 2001 Elsevier Science B.V. All rights reserved.