Titanium-Based Static Mixer Electrodes to Improve the Current Density of Slurry Electrodes

ChemElectroChem. 2023 Feb 1;10(3):e202200928. doi: 10.1002/celc.202200928. Epub 2023 Jan 10.

Abstract

Complex geometries for electrodes are a great challenge in electrochemical applications. Slurry electrodes have been one example, which use complex flow distributors to improve the charge transfer between the current collector and the slurry particles. Here we use titanium-based flow distributors produced by indirect 3D-printing to improve further the electron transfer from highly conductive flow distributors to the slurry particles for a vanadium redox flow application. The titanium static mixers are directly coated with graphite to increase the activity for vanadium redox reactions. Increasing layers of graphite have shown an optimum for the positive and negative electrolytes. The application of heat treatment on the electrodes improves the anodic and cathodic current peaks drastically. Testing the highly conductive static mixers in a self-made redox flow cell results in 110 mA cm-2 discharge polarization.

Keywords: conducting materials; electrochemistry; redox flow battery; slurry electrode; static mixer.