Spherically shaped vanadium pentoxide (V2O5) cathode powders with porous or dense morphologies are prepared directly via spray pyrolysis by varying the preparation temperatures between 600 and 1000°C. The powders prepared at 600°C consist of nanometer-sized rod-shaped crystals with porous structures. The V2O5 powders prepared at 1000°C have spherical shapes, clean surfaces, and dense structures, because of complete melting of the powders that occurs inside the hot-wall reactor. The Brunauer–Emmett–Teller (BET) surface areas of the V2O5 powders decrease from 24.7 to 3.2m2 g−1 when the preparation temperature increases from 600 to 1000°C. The V2O5 powders prepared at 1000°C have better cycle properties than those prepared at 600 and 800°C. The discharge capacity of the V2O5 powders prepared at 1000°C decreases from 432mAhg−1 to 263mAhg−1 after 20 cycles, in which the capacity retention is 61%.