TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preparation (Claimed): Preparation of (I) comprises: (a) preparing a mixture containing at least one lithium-, a manganese-, iron-, metal (M2+)- and phosphate ion (PO43-)-precursor compound; (b) heating the mixture at 450-850 degrees C; and (c) isolating (I). Preferred Process: In the step (a), further carbon containing components are added. In the step (c), the obtained (I) is mixed with the carbon containing components. Preferred Components: (I) additionally contain carbon, which is evenly distributed in the entire (I). The carbon of the each particle of the mixed (I) is covered. The amount of carbon in (I) is less than or equal to 4 wt.%. The cathode further contains lithium-metal-oxygen-compounds comprising lithium cobalt dioxide (LiCoO2) and lithium nickel oxide (LiNiO2), lithium iron phosphate (LiFePO4), lithium manganese phosphate (LiMnPO4) and/or lithium manganese iron phosphate (LiMnFePO4). The cathode is free of conductive additives. The lithium source comprises lithium hydroxide, lithium oxide, lithium oxalate, lithium acetate or lithium carbonate. The iron source is iron (Fe2+) salt comprising iron(II) sulfate, iron(II) chloride, iron(II) phosphate, iron(II) oxide, iron(II) hydrogen phosphate or iron-organyl salt or a iron (Fe3+) salt comprising iron(III) phosphate, iron(III) oxide, iron(III) chloride or mixed iron salts such as iron(II,III) oxide. The manganese source is manganese (Mn2+) salts comprising manganese(II) sulfate, manganese(II) chloride, manganese(II) oxide, manganese hydrogen phosphate, manganese oxalate, manganese acetate or a manganese (Mn3+) salt comprising manganese(III) phosphate, manganese(III) oxide, manganese(III) chloride or a mixed manganese salt such as manganese(II, III) oxide. The phosphate ion source is phosphoric acid, a phosphate, hydrogen phosphate, dihydrogen phosphate or phosphorus pentoxide. Preferred Definitions:    M = Zn or Ca (where y is greater then 0 to less than 0.15, and x is greater than 0 to less than 0.35) or Mg (where x is 0.01-0.11, y is greater than 0.07 to 0.20, and x+y is less than 0.2).    SPECIFIC COMPOUNDS - 3 Compounds (I) are disclosed i.e. lithium-manganese-metal phosphate compound of formula (LiMn(0.56)Fe(0.33)Mg(0.1)P04) (Ia), (LiMn(0.56)Fe(0.33)Mg(0.10)P04) (Ib) and (LiMn(0.80)Fe(0.10)Mg(0.10)P04) (Ic).    EXAMPLE - Lithium carbonate (92.9 g) with iron(III) phosphate monohydrate (47.02 g), manganese(II) carbonate (54.02 g) and manganese hydroxide (4.92 g) and cellulose acetate (5 wt.%) were wet-grinded in isopropanol. The solvent was evaporated and the dry mixture was then sintered in an inert gas chamber furnace at 750 degrees C for 11 hours. The resulting product was then ground with a variable speed rotor mill to obtain lithium-manganese-metal phosphate compound (Ia).