| 主权项 |
1. A method for producing a fused product comprising the following steps:
a) mixing raw materials so as to form a starting charge; b) performing step b1) or step b2) to melt the starting charge to obtain a liquid mass; c) cooling the liquid mass until there is complete solidification, so as to obtain a fused product in which the amount by weight of an amorphous phase is less than 80%; d) optionally, crushing and/or grinding and/or performing granulometric selection of said fused product; e) subjecting the fused product to thermal treatment at a plateau temperature less than a melting point Tm of said fused product and between Tm−800° C., or 500° C. if Tm−800° C. is less than 500° C., and Tm−50° C., for a holding time at the plateau temperature greater than 90 minutes, and in a reducing environment, said step e) being optional if step b2) is performed; and f) optionally, crushing and/or grinding and/or performing granulometric selection of said fused product; wherein: said fused product has a crystalline part including more than 99.3 wt % of one and the same crystalline phase of formula (Li1−aAa)1+x(G1−bJb)y[(XO4)1−dDd]zEe (LAGJXODE phase), in which (i) Li is the element lithium, (ii) A is a substituent of lithium selected from the elements Na, K, and mixtures thereof, (iii) a is less than or equal to 0.2, (iv) G is selected from the elements Fe, Mn, Ni, Co, V, and mixtures thereof, (v) J is a substituent of G selected from Nb, Y, Mg, B, Ti, Cu, Cr, and mixtures thereof, (vi) b is less than or equal to 0.5, (vii) XO4 is an oxoanion in which O denotes the element oxygen and X is selected from the elements P, S, Si, Nb, Mo, and mixtures thereof, (viii) D is selected from the anions F−, OH−, Cl−, and mixtures thereof, (ix) d is less than or equal to 0.35, (x) E is selected from the element F, the element Cl, the OH group, and mixtures thereof, (xi) 0≦e≦2, (xii) −0.2≦x≦2, (xiii) 0.9≦y≦2, and (xiv) 1≦z≦3; step b1) includes melting the starting charge until the liquid mass is obtained at a temperature Tlm greater than the melting point Tm of the fused product obtained at the end of step e); and step b2) includes melting the starting charge in an oxidizing environment until the liquid mass is obtained at a temperature Tlm greater than the melting point Tm of the fused product obtained at the end of step c), wherein when step b2) is performed: the LAGJXODE phase of the fused product is such that e=0, G is Fe and X is P; the element Fe is supplied to (i) more than 97% of its weight by FePO4(H2O)n with 0≦n≦6, (ii) more than 3% of its weight by Fe2O3, (iii) more than 5% of its weight by Fe3O4, or (iv) more than 97% of its weight by a mixture of FeO and of FePO4(H2O)n with 0≦n≦6, said mixture comprising less than 97% of FePO4(H2O)n with 0≦n≦6; and the temperature Tlm of step b2) being such that: Tlm is greater than 1250° C. and less than 1350° C. when the element Fe is supplied to more than 97% of its weight by FePO4(H2O)n with 0≦n≦6 or the mixture of FeO and of FePO4(H2O)n with 0≦n≦6; or Tlm is greater than 1350° C. when the element Fe is supplied to more than 3% of its weight by Fe2O3 or 5% of its weight by Fe3O4. |
