Patent ID: 7101521

Claim:
A method for the preparation of a cathode active material comprising: mixing, milling and sintering materials for synthesis of a compound represented by the general formula Li x FePO 4 , where 0<x<1; adding a carbon material at an optional time point in the course of said mixing, milling and sintering; employing Li 3 PO 4 and Fe 3 (PO 4 ) 2 or its hydrate Fe 3 (PO 4 ) 2 ·nH 2 O, where n denotes the number of hydrates, as the materials for synthesis of said Li x FePO 4 ; and exposing said compound after sintering to a gaseous medium, where the temperature is set to greater than or equal to 53° C. but less than or equal to 305° C.