Graphene-based materials as electrode constituents of energy storage devices

Energy production and storage have become key issues due to the ever-increasing demand of electricity in modern days. Rechargeable batteries are recognized as the primary power sources for applications from portable electronic devices to electric vehicles. Recently, there has been a growing interest in investigating graphene nanocomposite materials for various energy storage applications, such as electrode constituents in Li-based batteries (LiBs). With its unique structural, mechanical, and electrical properties, graphene can be a critical component in nanostructured electrode materials with improved capacity and cyclability, enabling the development of advanced batteries and new battery technologies to cover the increasing demand for high energy/power demanding applications.This contribution reviews the recent achievements in graphene utilization in negative electrodes for LiBs and introduces the latest progress of flexible graphene-based LiBs. In this respect, the application of vertically arranged multilayered graphene carbon nanowalls as high power LiB anode will be detailed as well as the novel spray-drying procedure towards hybrid 3D/2D Cu/Ni mixed oxide composite microspheres with graphene nanosheets. The superior cycling behaviour of the newly elaborated electrodes is demonstrated in lab-scale Li metal and Li-ion cells (LiFePO4 cathode and, eventually, polymer electrolyte separators) capable of very stable and prolonged reversible cycling with excellent durability exceeding thousands of cycles, good specific capacity and capacity retention when subjected to ultrafast current regimes. A survey of the scientific advances achieved thanks to the use of graphene in the so called “beyond Li-ion” technologies, namely Na-ion and Li-sulphur batteries, will be also envisaged.