Research Projects

Objective: New redox polymers with tuned redox potential. Aqueous, neutral pH, polymeric redox flow battery with energy density 20 Wh/L. Detail single cell performance evaluation and comparative data with VRFB.

Summary: Redox-active organic materials (ROMs) have been recently attracted intense research attention as alternative energy materials for achieving high-energy density, cost-effective, redox flow batterries (RFBs) compared with the benchmark vanadium redox flow battery (VRB) system. Very few redox active organic molecules (ROMs) possess a combination of compelling properties in terms of solubility, redox potential, cost, and stability which makes it even more challenging to couple two such ROMs into RFB chemistry of practical importance. To further advance the organic RFB technology, it is essential to extract the developmental pipeline from prior ROM design and prototyping efforts. One of the such organic molecule is 2,2,6,6-tetramethylpiperidine-1-oxy1 free radical (TEMPO). It’s thermodynamically stable and kinetically fast redox behavior makes it as an interesting starting point. They have exceptional stable charging/discharging characteristics in flexible secondary batterries. The first of kind organic radical battery (ORB) was proposed by NEC in 2001, where they have claimed the power density higher than the normal lithium ion-battery. The basic constituent of the battery was radical polymer made from polymerization of 4-(Glycidyloxy)-2,2,6,6-tetramethylpiperidine-1-oxy1 (epichlorohydrine modified TEMPO). In another report, poly (2,2,6,6-tetramethylpiperidinyloxy methacrylate) (PTMA), has been reported as an potential battery material. Norbornene as well as conducting polymer tethered TEMPO has been also reported as potential organic radical battery material. They have clearly demonstrated much higher power and energy densities, and found themselves into fore most candidates for future sustainable energy applications. Herein, we proposed the synthesis of different nitroxide, galvinoxyl and isoquinoline based redox active molecules as well as polymers for organic radical batteries which are believed to be most thermodynamically stable and kinetically fast redox moieties. Using these molecules, derivatives and polymers we have envisioned to make the flexible organic redox flow batteries with high power and energy densities compared to vanadium redox flow batteries for practical applications.