Hydrogen Reduction of LiCoO2 Cathode Mat

This study investigates the hydrogen reduction of LiCoO2 cathode material, focusing on its thermodynamic analysis, microstructure evolution, and the underlying reduction mechanisms. The objective is to explore hydrogen as a cleaner alternative to carbon for the recycling and recovery of cobalt and lithium from Li-ion battery materials. Methodologically, the study employs thermodynamic simulations paired with experimental work to assess reaction behavior and microstructural changes. Results indicate that metallic Co can be successfully generated starting at 400 °C, remaining stable up to 1200 °C, with its formation significantly influenced by the molar amount of H2 used. Final experimental outcomes reveal a range of reduction products, including Li2O, LiOH, Li2O2 for lithium, and Co, CoO, Co2O4 for cobalt, contingent on the reduction temperature. Notably, the period between 800 °C and 900 °C facilitates the generation of cobalt in larger masses, suggesting a more efficient reduction process during this range. Overall, the insights gained from this research are poised to optimize recycling parameters for Li-ion batteries.