The present invention relates to novel electrode active materials represented by the general formula AaMb(XY4)2Zd, wherein:(a) A is one or more alkali metals, and 0<a≦8;(b) M is at least one metal capable of undergoing oxidation to a higher valence state, and 1≦b≦3;(c) XY4 is selected from the group consisting of X′O4−xY′x, X′O4−yY′2−y, X″S4, and a mixture thereof, where X′ is P, As, Sb, Si, Ge, S, and mixtures thereof; X″ is P, As, Sb, Si, Ge, and mixtures thereof, Y′ is halogen, 0≦x<3, 0<y<4, and 0<c≦3; and(d) Z is OH, a halogen, or mixtures thereof, and 0<d≦6.