Synthesis of lithium-cobalt oxides by sol-gel method and their cathodical discharge behavior at 500 °C

Abstract

Three kinds of lithium-cobalt oxides with lithium to cobalt atomic ratios of 0.6, 0.8 and 1.0 respectively were prepared using nitrates and citric acid by sol-gel process. During the baking of the dry-gel powder, two exothermic peaks occur, followed by the formation of Li₂O and Co₃O₄ and then the combination of LiCoO₂, which is testified by DTA and XRD. The powder formed from an alkaline sol is finer than that from the acidic one. There are a single phase intercalation of lithium ion and an electrochemical reduction reaction for higher-valence cobalt ion when simulating the discharging process of Li-B/LiCl-KCl/lithium-cobalt oxides at 500 °C, and the voltage and specific capacity are not sensitive to the initial ratios of lithium to cobalt.

Keywords

sol-gel / LiCoO₂ / thermal battery / cathode

References

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