We report the outstanding electrochemical performance of LiNi0.5Mn1.5O4 porous microellipsoids with a core–shell configuration synthesized by a simple self-template method. The structure and electrochemical properties of the products are investigated via X-ray diffraction, scanning electron microscopy, Brunauer–Emmett–Teller method and various electrochemical analysis techniques. LiNi0.5Mn1.5O4 porous microellipsoids have a discharge capacity of 110.3 mA h g−1 after 400 cycles at a rate of 5C (735 mA g−1). The capacity retention ratio is 93.7% of the maximum capacity (142.3 mA h g−1) after 150 cycles under 5C rate at elevated temperature (55 °C). The porous ellipsoidal product could be a promising cathode material for high-performance lithium ion batteries.