TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Components: The inorganic material does not include a nitride of a transition metal. The compound with the olivine crystal structure is of formula (LixMeyMzPO4-dX1d) (I), (LixMn1-zM1zPO4-dX1d) (II), ((1-r)LixMeyMzPO4-dX1d-rM2bZ1c) (III) or ((1-r)LixMn1-zM1zPO4-dX1d-rM2bZ1c) (IV). The compound with the olivine crystal structure includes at least one comprising lithium iron phosphate, a metal compound of formula (LiFe1-aMnaPO4) (V) or lithium manganese phosphate. The inorganic material includes a nitride or carbide of a metalloid element comprising group 13, group 14 or group 15 of the periodic table of elements. The inorganic material includes boron. The inorganic material comprises at least one of boron nitride, boron carbide, silicon nitride, silicon carbide, boron nitride-boron carbide complex, boron nitride-silicon nitride complex and boron nitride-silicon carbide complex, preferably at least one of an amorphous boron nitride, a boron nitride with a cubic crystalline structure, a boron nitride with a hexagonal crystalline structure, and a boron nitride with a wurtzite crystalline structure. The inorganic material is in the form of at least one comprising a nanoparticle, nanofiber, nanomesh and nanotube. The inorganic material has a Mohs hardness greater than a Mohs hardness of the compound with the olivine crystal structure. The inorganic material has an electrical conductivity lower than that of amorphous carbon. The inorganic material has: a Mohs hardness of 1 or greater; and an electrical conductivity of 10-1 S/cm or less. The composite cathode active material further comprises a carbonaceous material. The carbonaceous material is present at 0.1-30 wt.%. The precursor of the compound with the olivine crystal structure includes lithium precursor, phosphate precursor, and transition metal precursor. In formula (I):x = 0.6-1.1;y = 0-1.1;z = 0-1;x+y+z = 1.6-2.2;d = 0-0.2;Me = Fe, Mn, Ni or Co;M = Mg, Ca, Cu, Nd, Sr, Ba, Ti, Zr, Nb, Mo, W, Zn, Al or Si; andX1 = S or F.In formula (II):x = 0.6-1.1;z = 0-0.2;d = 0-0.2;M1 = Fe, Ni, Co, Mg, Ca, Cu, Nd, Sr, Ba, Ti, Zr, Nb, Mo, W, Zn, Al or Si; andX1 = S or F.In formula (III):x = 0.6-1.1;y = 0-1.1;z = 0-1;x+y+z = 1.6-2.2;d = 0-0.2;r = 0-1 (preferably 0.01-0.3);Me = Fe, Mn, Ni or Co;M = Mg, Ca, Cu, Nd, Sr, Ba, Ti, Zr, Nb, Mo, W, Zn, Al or Si;M2 = B, Si, Ge, As or Sb;Z1 = C or N;X1 = S or F;b = 1-5; andc = 1-5.In formula (IV):x = 0.6-1.1;z = 0-0.2;d = 0-0.2;r = 0-1 (preferably 0.01-0.3);M1 = Fe, Ni, Co, Mg, Ca, Cu, Nd, Sr, Ba, Ti, Zr, Nb, Mo, W, Zn, Al or Si;X1 = S or F;M2 = B, Si, Ge, As or Sb;Z1 = C or N;b = 1-5; andc = 1-5.In formula (V):a = 0-1.Preferred Method: The step of sintering is performed at 400-900 degrees C for 2-48 hours.