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A novel graphite material for lithium ion batteries was prepared by encapsulation of an ionic conductive polymer on the surface of natural graphite particles via radiation-initiated polymerization. The graphite obtained shows great improvement in electrochemical performance such as initial coulombic efficiency and cycleability compared with the original natural graphite. Raman spectroscopy indicates that the structural stability of the graphite surface is enhanced due to the fact that encapsulated polymers can depress the exfoliation of graphite layers caused by co-intercalation of solvent molecules. The solid electrolyte interface (SEI) film formed on the encapsulated graphite electrode retains a stable morphology during repeated cycling, and thus avoids an increase in the electrode's impedance.

We have obtained carbon anode materials based on a melamine resin. Through elemental analysis, X-ray powder diffraction, BET measurement and X-ray photoelectron spectroscopy, the effects of heat-treatment temperature and doping of phosphorus were investigated. Temperature affects mainly the nitrogen content, the size of graphite crystallites and the number of micropores in the carbons, and thus their reversible capacity changes with temperature. The highest reversible capacity occurs at 600 °C. The addition of phosphoric acid can affect the carbon structure and relative content of graphene nitrogen. Its behaviour changes with temperature. Only at high temperature, can the doped phosphorus favour the enhancement of reversible capacity.

An ionic liquid polymer, poly (1-alkyl-3-(acryloyloxy)hexylimidazolium iodide), was employed as an iodine-free electrolyte in all-solid-state dye-sensitized solar cells with an overall conversion efficiency of 5.29% under AM 1.5 simulated solar light (100 mW cm(-2)) illumination.

Nanocomposite polymer electrolytes containing poly(ether urethane) (PEUR)/poly(ethylene oxide) (PEO)/modified SiO(2) were prepared for all-solid-state dye-sensitized solar cells with a high efficiency of 4.86% and an active area of 0.25 cm(2) under AM1.5 conditions at 100 mW cm(-2) irradiation.