CATHODIC ACTIVE MATERIAL, CATHODE, AND NONAQUEOUS SECONDARY BATTERY

摘要

A cathodic active material invention has a composition represented by general formula (1): Li(1-a)A a Fe(1-x-b)M(x-c)P(1-y)Si y O4 .multidot. (1), where A is at least one type of element selected from the group consisting of Na, K, Fe, and M; Fe has an average valence of +2 or more; M is an element having a valence of +2 or more and at least one type of element selected from the group consisting of Zr, Sn, Y, and Al, the average valence of M being different from the average valence of Fe; 0 < a <= 0.125; a = b + c + d, where b is the number of moles of Fe in A, c is the number of moles of M in A, and d is the total number of moles of Na and K in A; 0 < x <= 0.5; and 0 < y <= 0.5. The cathodic active material not only excels in terms of safety and cost, but also can provide a long-life battery.