An electrochemically active nanostructured silver copper fluoride (SCF) perovskite, AgCuF3, was synthesized via a mechanochemical reaction between AgF and CuF2 precursors. Phase composition and electrochemical properties of the SCF perovskites produced under various synthetic parameters were studied. The optimum SCF perovskite sample exhibited an appreciable electrochemical performance through the use of conductive carbon matrix in a primary lithium half cell. A high specific capacity of 270 mAh g−1 was achieved at a cutoff voltage of 2 V with 190 mAh g−1 above 3 V, leading to a total volumetric energy density of 3666 Wh L−1 at >3 V and 4848 Wh L−1 at >2 V.