Electrochemical Reactivity and Wetting Properties of Anodes Made from Anisotropic and Isotropic Cokes

Abstract

High quality anodes require stable raw materials. As the quality of the coke available for production of anodes is changing, future production will rely on cokes that are more isotropic with higher impurity levels than traditional raw materials. The purpose of this work was to improve the understanding of the electrochemical reactivity of different cokes. An-ode:electrolyte wetting is a key factor towards deter-mining electrochemical reactivity, which in turn is affected by anode properties, type of coke and po-larization. Pilot anodes were fabricated from single source cokes; one anisotropic coke low in impurities, and one isotropic coke with significantly higher im-purity levels. Electrochemical characterisation in-cluded chronopotentiometry, cyclic voltammetry and impedance spectroscopy. Wetting properties were studied on both unpolarised and polarised samples by a dedicated wetting apparatus, and indirectly by com-puted tomography (CT) images of frozen electrolyte films.