Rechargeable battery technologies (such as Li-ion, Li-S, Na-ion, Li-O2 batteries) and supercapacitors are among the most promising power storage and supply systems in terms of their widespread applicability, and tremendous potential owing to their high energy and power densities.
In this review, we focus on the topics of supercapacitors and batteries, which include lithium ion batteries (LIBs), sodium ion batteries (SIBs), and Li-S batteries. Fig. 1 shows a Ragone diagram comparing the energy density and power density of different energy storage devices and a combustion engine.
Layered materials, which have a unique anisotropic structure with strong in-plane bonds but weak interaction between layers, have been widely investigated as electrodes for batteries and supercapacitors. However, their limited capacity and sluggish ion diffusion hinder their ability to meet the requirements for higher energy and power density.
The energy storage mechanisms for batteries and supercapacitors mainly include intercalation/de-intercalation, conversion, alloying/de-alloying, and surface capacitive adsorption/desorption.
6.1.1. Graphite Graphite is perhaps one of the most successful and attractive battery materials found to date. Not only is it a highly abundant material, but it also helps to avoid dendrite formation and the high reactivity of alkali metal anodes.
Applications of nanomaterials in batteries and supercapacitors include: Electrodes in batteries and capacitors. Anodes, cathodes and electrolytes in Li-ion (LIB) batteries. Inks printable batteries and supercapacitors. LIB cathodes. Anode coatings to prevent corrosion. Nanofiber-based polymeric battery separators. Biodegradable green batteries.