A sustainable platform of lignin: From bioresources to materials and their applications in rechargeable batteries and supercapacitors

Lignin, as a renewable bioresource, has been widely explored in cellulosic biofuel and several other industries. There are limited applications of lignin in the energy industry, especially in rechargeable batteries and supercapacitors, even though tremendous research work has been done regarding the use of lignin in these fields. It is vital to take lignin into consideration because its usage not only improves the performance of these devices but also reduces the cost, contributing to obtaining more sustainable and greener energy devices. This paper reviews recent developments of lignin-derived materials in rechargeable batteries and supercapacitors. It starts with a brief introduction of the benefits of lignin, followed by the fundamental nature and preparation of lignin-derived materials. Significant attention is paid to applications of lignin-derived materials in rechargeable batteries and supercapacitors including their use as binders and electrodes for rechargeable batteries, and electrodes and electrolytes for supercapacitors with a focus on the mechanisms behind their operation. The goal is to provide a detailed review of the critical aspects related to lignin utilized as an important resource for researchers working in a diverse range of fields dealing with energy storage and conversion. Lastly, a future vision on challenges and their possible solutions are presented.