Synthesis and structural characterization of some cathode materials for lithium-ion batteries

Abstract

Lithium-ion batteries are under intense scrutiny as alternative energy/power sources. Their electrochemistry is based on intercalation/deintercalation reactions of lithium ions within a crystal structure of an electrode material. Therefore, the structure itself determines both the electrode operating voltage and the transport pathways for lithium ions. Some oxide- and polyanion-based materials are synthesized by using ultrasonic spray pyrolysis method. The crystal structure refinement was based on the Rietveld full profile method. All relevant structural and microstructural crystal parameters that could be significant for electrochemical intercalation/deintercalation processes were determined. It was also shown that the structural and microstructural properties are significantly dependent on the synthesis condition. Electrochemical performances as cathode materials for lithium-ion batteries were examined through galvanostatic charge/discharge cycling. Galvanostatic cycling revealed variation in discharge curve profiles. It comes from different mechanism of lithium intercalation and also from the degree of structural order. Structural analyses revealed difference in the dimensionality of lithium-ion motion.