Oxynitride-Based Electrode Active Materials For Secondary Electrochemical Cells

An electrochemical cell, comprising:

• a first electrode comprising an electrode active material represented by the general formula:
• AaMbXc[O(3c+1)−d,Ne]
• wherein:
• (a) A is at least one alkali metal, and 0<a≦6;
• (b) M is at least one redox active element, wherein 1<b≦4;
• (c) X is selected from the group consisting of P, As, Sb, Si, Ge, V, S, and mixtures thereof;
• (d) 2≦c≦5, 0<d≦(3c+1), and 0<e≦d;
• and
• (e) A, M, X, a, b, c, d and e are selected so as to maintain electroneutrality of the material in its nascent or “as-synthesized” state;
• a second electrode;
• and
• an electrolyte for transferring ionic charge carriers between the first electrode and the second electrode.