METHOD FOR PRODUCING LITHIUM-CONTAINING COMPLEX OXIDE FOR POSITIVE ELECTRODE OF LITHIUM SECONDARY BATTERY

摘要

Disclosed is a positive electrode active material for lithium secondary batteries which is low in gas generation and high in safety while having excellent resistance to charge/discharge cycles even at a high charging voltage. Specifically disclosed is a method for producing a lithium-containing complex oxide represented by the following general formula: Li_pL_qN_xM_yO_zF_a (wherein L is B and/or P; N represents at least one element selected from the group consisting of Co, Mn and Ni; M represents at least one element selected from the group consisting of transition metal elements other than L and N, Al and alkaline earth metal elements; and 0.9 = p = 1.1, 0 = q = 0.03, 0.97 = x < 1.00, 0 = y = 0.03, 1.9 = z = 2.1, q + x + y = 1, and 0 = a = 0.02). In this method, a lithium complex oxide powder containing the N element, and if necessary the M element and fluorine, is produced; then the lithium complex oxide powder is mixed with an aqueous solution containing a source of the L element; and then the water solvent is removed from the thus-obtained mixture and the resulting is fired at 300-1050°C in an oxygen-containing atmosphere.