LITHIUM SILICATE COMPOUND, METHOD FOR PRODUCING SAME, POSITIVE ELECTRODE ACTIVE MATERIAL AND POSITIVE ELECTRODE FOR SECONDARY BATTERIES, AND SECONDARY BATTERY

摘要

This lithium silicate compound is represented by general formula Li2-a+bAaMn(1-x-y)CoxMySiO4+alphaClbeta (wherein A represents at least one element that is selected from the group consisting of Na, K, Rb and Cs; M represents at least one element that is selected from the group consisting of Mg, Ca, Al, Ni, Fe, Nb, Ti, Cr, Cu, Zn, Zr, V, Mo and W; and the subscripts respectively satisfy 0 <= a < 0.2, 0 <= b < 1, 0 < x < 1, 0 <= y <= 0.5, -0.25 <= alpha <= 1.25 and 0 <= beta <= 0.05). This lithium silicate compound is used as a positive electrode active material for secondary batteries, which has a high discharge average voltage and is capable of absorbing and desorbing lithium ions.