Synthesis and characterization of amorphous 3Fe2O3•2P2O5•10H2O and its electrode performance in lithium batteries

Amorphous 3Fe(2)O(3). 2P(2)O(5). 10H(2)O was prepared by oxidation of iron (II) phosphate, obtained by spontaneous precipitation from iron(II) and phosphate aqueous solutions, by hearing in air at 100 degreesC. The material was characterized by thermal analysis, Mossbauer spectroscopy, X-ray powder diffraction, and scanning electron micrograph analysis. The material, tested as cathode in a nonaqueous lithium cell, exhibited a specific capacity of about 140 mAh g(-1) at a cur-rent density of 25 mA g(-1). The utilization was reduced to about 76% by a tenfold increase of the discharge current. it showed an excellent cyclability. More than 1000 cycles were performed at about 50% of depth of discharge, with a capacity fade lower than 0.025%. (C) 2001 The Electrochemical Society.