SYNTHESIS OF LITHIUM-IRON-PHOSPHATES UNDER HYDROTHERMAL CONDITIONS

摘要

The present invention relates to a process for the preparation of compounds of general formula (I) Lia-bMb1Fe1-cMc2Pd-eMe3Ox, wherein Fe has the oxidation state +2 and M1, M2, M3, a, b, c, d, e and x are: M1: Na, K, Rb and/or Cs, M2: Mn, Mg, Al, Ca, Ti, Co, Ni, Cr, V, M3: Si, S, F a: 0.8-1.9, b: 0-0.3, c: 0-0.9, d: 0.8-1.9, e: 0-0.5, x: 1.0-8, depending on the amount and oxidation state of Li, M1, M2, P, M3, wherein compounds of general formula (I) are neutrally charged, comprising the following steps (A) providing a mixture comprising at least one lithium-comprising compound, at least one iron-comprising compound, in which iron has the oxidation state 0, and at least one M1-comprising compound, if present, and/or at least one M2-comprising compound, if present, and/or least one M3-comprising compound, if present, and at least one compound comprising at least one phosphorous atom in oxidation state +5, and (B) heating the mixture obtained in step (A) at a temperature of 100 to 500° C. and at an autogeneous pressure to obtain a compound of general formula (I).