Abstract: A method of preparing LiFePO4/Li3V2(PO4)3 composite cathode materials and their applications as cathode materials for lithium ion batteries are disclosed. The preparation method includes the following steps: (A) providing a mixture of iron powder, lithium salt, vanadium salt, and a phosphate salt whereafter these compounds are dissolved into a mixed acid solution; (B) drying the solution in order to obtain precursor powders; and (C) heating the precursor powders at a temperature ranging between 400 and 1000° C. to form LiFe1-y?Vy?PO4/Li3V2-y?Fey?(PO4)3 composite powders. Alternatively, prepare the composite cathode by preparing olivine LiFe1-y?Vy?PO4 and monoclinic Li3V2-y?Fey?(PO4)3 powders as in previous procedures followed by mixing adequately. The low cost of iron powder thus facilitates to prepared composite cathode materials exhibiting higher electrical conductivity and superior cycling performance at high C rates than those of olivine LiFe1-y?Vy?PO4 and monoclinic Li3V2-y?Fey?(PO4)3.

Abstract: A method for producing a positive electrode material adapted to the Li-ion secondary batteries is disclosed. The produced material has the following formula (I), Li1+xMn2?yMyO4 ??(I) wherein M is Mg, Al, Cr, Fe, Co, or Ni; 0?x?0.4, and 0?y?0.2. The method is achieved by co-precipitating a gel salts with an organic acid. First, salts of Li, Mn and M are mixed with at least a solvent to form an initial solution. The mole ratio of Li, Mn and M ions in their respective salts is (1+x):(2?y):y. Next, at least a chelate is added into the initial solution to form a suspension, which is then filtered to obtain a co-precipitate. Finally, the co-precipitate is calcined and heated to obtain the final product.

Abstract: A method for producing a positive electrode material adapted to the Li-ion secondary batteries is disclosed.

Abstract: A method for producing a positive electrode material of Li-ion secondary batteries is disclosed.

Abstract: A positive electrode material of a Li-ion secondary battery is disclosed. This positive electrode material has a formula of Li1+xMn2−yMyO4−zClz, wherein M can be magnesium (Mg), aluminum (Al), chromium (Cr), iron (Fe), cobalt (Co) or nickel (Ni) ions, 0≦x≦0.4, 0≦y≦0.3, and 0.01≦z≦1.0. By means of replacing some oxygen ions of this material with chlorine ions, the crystalline structure thereof can be varied and thus longer life cycle and better stability at high temperature can be achieved.