AUTHOR=Quiroga-González Enrique , Morales-Merino Emma TITLE=Mexican Onyx Waste as Active Material and Active Material’s Precursor for Conversion Anodes of Lithium Ion Batteries JOURNAL=Frontiers in Energy Research VOLUME=9 YEAR=2021 URL=https://www.frontiersin.org/journals/energy-research/articles/10.3389/fenrg.2021.593574 DOI=10.3389/fenrg.2021.593574 ISSN=2296-598X ABSTRACT=

For the first time a limestone has been used as active material or active material’s precursor for electrodes of Li ion batteries. Limestones are very abundant, what is a condition for a sustainable development of energy storage devices. Mexican onyx has been used as a model of limestone in this work, mainly composed of calcite (calcium carbonate). Waste powder of this material from handcraft production was used, reducing costs. The material was carbonized and pyrolyzed, producing calcium oxide covered with carbon. Mexican onyx either treated or untreated works well as anode material for Li ion batteries, storing charges by conversion. Despite the grains of this material were as big as 50 μm, the material with no treatment showed a maximum Li storage capacity of 530.16 mAh/g at C/3.3, while the pyrolyzed one showed a maximum reversible capacity of 220 mAh/g at 1.37C and of 158 mAh/g at 5.48C, performance even better than the performance of graphite.