Automated Electrochemical Characterization for Redox Flow Batteries Using The Electrolab: Molecules, Polymers, Electrolytes and their Complex Interactions

Designing superior redox flow batteries (RFBs) requires advanced electrochemical characterization techniques that elucidate manifold transport, reactivity, stability, and interactive properties of molecules, electrolytes, and other materials present in these systems. The modularity of many RFB designs enables significant flexibility in the choice of experimental conditions, thus making it imperative to swiftly identify those that lead to improved properties. This not only requires the ability to carry out many experiments in a timely fashion, but also to use electroanalytical approaches in a comprehensive and clever way. To accomplish these objectives, our group has recently introduced The Electrolab, an automated electrochemical platform that combines hardware, software, a dispensing robot, and custom designed e-chips which altogether enable characterization campaigns with minimal supervision while maximizing diagnostic power. The Electrolab is sufficiently versatile to enable both relatively simple but tedious experiments such as determining diffusion coefficients, to systematic experiments incorporating titrations, to more sophisticated measurements of lifetime of redox species using microelectrode e-chips.<br/>In this presentation, we will first describe new opportunities in the use of redox-active polymers for the construction of redox flow batteries. Unlike small molecules, polymeric redox active materials exhibit dynamics that are highly dependent on aspects such as electrolyte concentration and type. I will then explain how the Electrolab incorporates functions to systematically explore these dependencies, including automated robotic titrations which enable to rapidly identify limiting factors. Finally, I will describe how a different type of redox titration experiment based on scanning electrochemical microscopy can be developed and automated to understand charge transfer performance between redox mediators and charge storage media such as redox polymers. Putting together automated electrochemistry, advanced techniques based on microelectrodes, and new concepts for energy storage based on polymeric materials, promises new directions in the identification of RFB systems.