Structure and electrochemistry of FePO4∙2H2O hydrate

K. Zaghib , Christian Julien (1)

1 INSP - Institut des Nanosciences de Paris

We report the structural and electrochemical characteristics of FePO4 dihydrate exhibiting a monoclinic structure (P21/n space group). We have applied Raman and FTIR spectroscopy to study the local structure. Vibrational features analyzed using the molecular group model show the strong inductive effect in the [FePO4] framework. The electrode FePO4·2H2O material inserts 0.7 Li ions per mole leading to coulombic efficiency of 74% for the first cycle and specific capacity of 106 mAh g−1. Infrared spectrum of the lithiated product shows structural modifications due to the lithium insertion and the reduction of iron ions.

Mots clés: Iron phosphate; Lithium batteries; Raman; FTIR

K. Zaghib, Christian Julien. Structure and electrochemistry of FePO4∙2H2O hydrate. Journal of Power Sources, 2005, 142 (1-2), pp.279. ⟨10.1016/j.jpowsour.2004.09.042⟩. ⟨hal-00017249⟩