Sol–gel synthesis and electrochemical properties of c-axis oriented LiCoO2 for lithium-ion batteries

Abstract

To improve the performance of LiCoO₂ as a cathode for lithium-ion batteries, the electrochemical properties of c-axis oriented LiCoO₂ were studied. LiCoO₂ samples with controllable intensity ratios of peak (003) to peak (104) were synthesized via a resorcinol–formaldehyde sol–gel method, followed by an air-controlled high temperature treatment. Electrochemical measurements showed that LiCoO₂ with a low degree of c-axis orientation exhibited better performance than LiCoO₂ with a high degree of c-axis orientation. X-ray absorption spectroscopy was used to reveal the texture–property relationship between the different products. The variances could be attributed to the different electrochemical active sites created and the diffusion lengths for the lithium ions related to c-axis orientation.