Controlling Electrodeposition Via Electrokinetic Phenomena and Phase Separation

Abstract

This talk will review the basic physics of dendritic instabilities in electrodeposition and how they may be suppressed, in some cases, by controlling electrokinetic phenomena in the electrolyte or phase separation in the electrode: 1) It is shown both theoretically and experimentally that, if electrodeposition occurs in charged porous media above the diffusion-limited current, then dendritic growth can be suppressed by surface conduction and electro-osmotic flows through the phenomenon of “shock electrodeposition”, as in many examples with copper. 2) It is also shown theoretically and experimentally that dendritic electrodeposition on a multiphase electrode can be avoided by avoiding the separation of a resistive phase, as illustrated by lithium plating on graphite. Examples include composite metal materials manufacturing, metal nanotube growth in templates, rechargeable metal batteries, and conductive-bridge random access memory (CB-RAM). These phenomena may also be leveraged to enhance the selectivity of electrodeposition for metal separations.