Carbon nano-onion-modified Ni-cathode materials for Ni-based batteries and a sustainable future

Identifier:  TFM:563

Handle: https://hdl.handle.net/20.500.11797/TFM563

Authors:  Andreo Acosta, Andrés Alberto

Abstract:
Ni-based batteries like Ni-Fe, Ni-Zn and Ni-MH were extendedly used in the previous century since their invention due to their great efficiency, high output power and eco-friendly and safe character. Nonetheless, their relatively low cycle life and material instabilities set them aside from the future large-scale production and commercialisation in favour of other systems such as the Li-ion and Pb-acid batteries. In order to overcome these limitations, in the current work we analyse the improvement in performance derived from the use of carbon nano-onions (CNOs) compared to other carbon materials, e.g. graphite powder, in the design and fabrication of cathode materials. In these terms, we fabricated CNOs/Ni(OH)2 composites-modified glassy carbon electrodes (GCEs) that enhanced the electrochemical signal by a maximum factor of 10 in cyclic voltammetry studies, and the specific capacity of the electrodes from 20.4 to 72.3 mAh=g, with a capacity retention of 62.6% at a rate of 10 C after 5 cycles. Moreover, we further analyse and compare the distinct role of several syntheses of and nickel hydroxides in the electrochemical performance and behaviour as the cathode active materials for the mentioned Ni-based batteries.