Potentiostatic and Galvanostatic Intermittent Titration Techniques

This article is concentrated on the essentials of potential and current pulses techniques, commonly known as potentiostatic and galvanostatic intermittent titration techniques (PITT and GITT, respectively). They were introduced around 35 years ago to provide thermodynamic and kinetic characterization of two- and three-component metallic alloys with Li, and were thereafter widely used for studies of Li-ion insertion into a variety of intercalation-type anodes andcathodes. Emphasis is given to description of ion diffusion in finite (confined) space versus semi-infinite diffusion in classical electrochemical cells. Special attention is also paid to intrinsic link between the diffusion time constant obtained from different electroanalytical techniques used and its dependence on the shape of the related ion intercalation isotherm. We also discuss the advantages and disadvantages in using separate incremental titration techniques as well as electrochemical impedance spectroscopy for detecting diffusion coefficients.