Systems and methods for an ultra-high voltage cobalt-free cathode for alkali ion batteries may include an anode, a cathode, and a separator, with the cathode comprising an active material ANi(1-x)MnxSbOy, where x is a number between 0.0 and 1.0, y is an integer, and A comprises one or more of lithium, sodium, and potassium. The anode may include one or more of an alkali metal, silicon, and carbon. In one example, x is a value in the range between 0.05 and 0.9 and y is a value in the range between 1 and 8 where a specific capacity of the active material is greater than 50 milliamp-hours per gram. In another example, x is a value in the range between 0.4 and 0.6 and y is a value in the range between 1 and 8, where a specific capacity of the active material is greater than 70 milliamp-hours per gram.