Porous LiNi0.75Co0.25O2 microspheres prepared via a hydrothermal process as cathode material for lithium ion batteries

Porous LiNi0.75Co0.25O2 microspheres are successfully prepared by a simple hydrothermal process by using H[Ni0.75Co0.25OOH]3 and LiOH as starting materials in the presence of urea for the first time. The synthesized samples are characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), specific surface area (SBET), and electrochemical performance. The synthesized LiNi0.75Co0.25O2 has a good electrochemical performance with an initial discharge capacity of 169.3 mA g−1 and good capacity retention of 96.7% after 50 cycles at 0.2 C (25 mA g−1). The electrochemical lithium ion insertion/extraction process is quite reversible even at 5 C. Furthermore, the structure in the charge–discharge process is stable and the impedance increased slowly during cycling.