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Amorphous iron͑III͒ phosphate was synthesized by spontaneous precipitation from equimolar aqueous solutions of Fe(NH 4 ) 2 (SO 4 ) 2 •6H 2 O and NH 4 H 2 PO 4 , using hydrogen peroxide as the oxidizing agent. The material was characterized by chemical analysis, thermogravimetrical analysis, differential thermoanalysis, X-ray powder diffraction, and scanning electron microscopy. The material was tested as a cathode in nonaqueous lithium cells. Galvanostatic intermittent titration technique was used to follow the lithium intercalation process. The effect of firing on the specific capacity was also tested. The material fired at 400°C showed the best electrochemical performance, delivering about 0.108 Ah g Ϫ1 when cycled at C/10 rate. The capacity fade upon cycling was found as low as 0.075% per cycle.

Nanocrystalline LiFePO4 was obtained by heating amorphous nanosized LiFePO4. The amorphous material was obtained by lithiation of FePO4 synthesized by spontaneous precipitation from equimolar aqueous solutions of normalFefalse(NH4)2false(SO4)2⋅6H2O and NH4H2PO4, using hydrogen peroxide as the oxidizing agent. The materials were characterized by chemical analysis, thermogravimetric and differential thermal analysis, X-ray powder diffraction, and scanning electron microscopy. The Brunauer- Emmett-Teller method was used to evaluate the specific surface area. Nanocrystalline LiFePO4 showed very good electrochemical performance delivering about the full theoretical capacity false(170 Ah kg−1false) when cycled at the C/10 rate. A capacity fade of about 0.25% per cycle affected the material upon cycling. © 2002 The Electrochemical Society. All rights reserved.

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