Solution combustion synthesis of layered LiNi0.5Mn0.5O2 and its characterization as cathode material for lithium-ion cells

LiNi0.5Mn0.5O2, a promising cathode material for lithium-ion batteries, is synthesized by a novel solution-combustion procedure using acenaphthene as a fuel. The powder X-ray diffraction (XRD) pattern of the product shows a hexagonal cell with a = 2.8955 Å and c = 14.1484 Å. Electron microscopy investigations indicate that the particles are of sub-micrometer size. The product delivers an initial discharge capacity of 161 mAh g−1 between 2.5 and 4.6 V at a 0.1 C rate and could be subjected to more than 50 cycles. The electrochemical activity is corroborated with cyclic voltammetric (CV) and electrochemical impedance data. The preparative procedure presents advantages such as a low cation mixing, sub-micron particles and phase purity.

► LiNi0.5Mn0.5O2 is a promising cathode material for lithium-ion batteries but cation mixing is a problem.
► A novel acenaphthene assisted solution combustion (AASC) process used to overcome cation mixing problem.
► AASC enables least cation mixing, near nano structures, phase purity, etc. as compared to other synthesis techniques.
► XRD I0 0 3/I1 0 4 indicates electrochemical reactivity—obtained value of 1.5688 is the maximum one traced in literature.
► AASC process enables to synthesize best layered lithium cathode active materials.