The invention relates to novel electrodes containing one or more active materials comprising: AaM1vM2wM3xM4YM5zO2−C(Formula 1) wherein A comprises either sodium or a mixed alkali metal in which sodium is the constituent; M1 is nickel in oxidation state less than or equal to 4+, M2 comprises a metal in oxidation state less than or equal to 4+, M3 comprises a metal in oxidation state 2+, M4 comprises a metal in oxidation state less than or equal to 4+, and M5 comprises a metal in oxidation state 3+ wherein 0≦a≦1 v>0 at least one of w and y is >0 x≧0 z≧0 c>0.1 where (a, v, w, x, y, z and c) are chosen to maintain electroneutrality. Such materials are useful, for example, as electrode materials in sodium-ion battery applications. AaM1VM2WM3XM4YM5ZO2−c  (Formula 1)