Spray-drying synthesis of LiMnO2@VXC-72R composite microspheres with excellent electrochemical performance

A facile synergetic strategy is reported for the synthesis of the LiMnO2@VXC-72R composite microspheres by applying spray-drying technique with nanosized LiMnO2 particles as host material and conductive carbon black (VXC-72R) as dispersing agent. In this hybrid structure, LiMnO2 nanoparticles promote the lithium-ion diffusion due to the nanosized diffusion distance, whereas well-distributed VXC-72R suppress the aggregation of LiMnO2 nanoparticles and enhance the electronic conduction. Moreover, the micro-sized spherical morphology with low specific surface area is conducive to reducing the contact area between electrolyte and composite cathode, which inhibit the manganese dissolution. Benefiting from their synergistic effect, the LiMnO2@VXC-72R composite microspheres achieve the maximum discharge capacity of 187.3 mAh g(-1) with good cycling stability at 0.1 C. After 50 cycles, the discharge capacity of composite cathode is still maintained at 173.2 mAh g(-1), which is significantly higher compared to the primary LiMnO2 particles. Moreover, the LiMnO2@VXC-72R composite microspheres exhibit outstanding rate performance with high discharge capacity.