Kinetics of the electrochemical intercalation of lithium into carbon and silicon-carbon films: The determination by non-steady-state techniques

Kinetics of the electrochemical intercalation of lithium into thin pyrolyti c-carbon and silicon-carbon films on nickel substrates is determined using potentiostatic and galvanostatic switching-on techniques. The investigation is carried out at 298 K in 1 M LiClO4 solutions in mixed organic solvents, such as propylene carbonate + dimetoxyethane (7 : 3) and propylene carbona te + diethylcarbonate (3 : 1). The polarization curves are linear at polari zations of -0.100 to 0.100 V. The polarization resistance depends on the na ture of the film and solvent and on the currentless electrode storage time. Lithium diffusion coefficients in carbon and silicon-carbon matrices are d etermined.