Measurements of the electric conductivity of an electrode as it transitions between static and flowable modes

Abstract

Electrochemical systems which store energy or desalinate water employ either static electrodes or flowable suspension electrodes. Flowable electrodes enable important functionalities not available to static electrodes, but suffer from significantly lower electric conductivity, typically of order 1 or 10 mS/cm. To combine the benefits of static and flowable electrodes, we here propose and demonstrate an electrode which can be switched between a flow-through static mode and flowable mode in operando. We provide first-time measurements of the electrode's electric conductivity as it undergoes velocity cycling and transitions between modes. The electrode achieves a gigantic conductivity of over 10,000 mS/cm while in static mode, and demonstrates repeatable switching between static and flowable modes at a tunable transition velocity. Such switchable electrodes can in the future enable novel, highly versatile electrochemical systems. Keywords: Electrochemistry, Energy conversion, Flowable electrodes, Flow batteries, Capacitive deionization