Abstract
Diffusion coefficients of ion in graphitic materials are responsible for high-rate batteries. However, the complex electrochemical response presented a challenge to accurately measure the diffusion coefficient of alkali-metal ions in graphitic materials. Here we design a method to identify the diffusion coefficients of Li+ and Na+ in highly oriented pyrolytic graphite (HOPG) with and without presence of liquid electrolyte infiltration. The results reveal inherent high diffusivity of Li+ in HOPG (∼10−7 cm2·s−1), as compared to HOPG with electrolyte infiltration (∼10−8 cm2·s−1), while Na+ has almost no interlayer diffusion without solvent infiltration. The presence of electrolyte has different effect on the interlayer diffusion of Li+ and Na+.
Funder
National Key R&D Program of China
National Natural Science Foundation of China
Publisher
The Electrochemical Society
Subject
Materials Chemistry,Electrochemistry,Surfaces, Coatings and Films,Condensed Matter Physics,Renewable Energy, Sustainability and the Environment,Electronic, Optical and Magnetic Materials