In situ electrochemical-electron spin resonance investigations of multi-electron redox reaction for organic radical cathodes

Journal Article · Mon Feb 29 04:00:00 EST 2016 · Journal of Power Sources

DOI:https://doi.org/10.1016/j.jpowsour.2015.11.080· OSTI ID:1243182

Huang, Qian; Walter, Eric D.; Cosimbescu, Lelia; Choi, Daiwon; Lemmon, John P.

Organic radical batteries (ORBs) bearing robust radical polymers as energy storage species, are emerging promisingly with durable high energy and power characteristics by unique tunable redox properties. Here we report the development and application of in situ electrochemical-electron spin resonance (ESR) methodologies to identify the charge transfer mechanism of Poly(2,2,6,6- tetramethylpiperidinyloxy-4-yl methacrylate) (PTMA) based organic radical composite cathodes in the charge-discharge process of lithium half cells. The in situ experiments allow each electrochemical state to be associated with the chemical state (or environment) of the radical species upon the cell cycling. In situ ESR spectra of the composite cathode demonstrate a two-electron redox reaction of PTMA. Moreover, two different local environments of radical species are found in the composite electrode that includes both concentrated and isolated radicals. These two types of radicals show similarities during the redox reaction process while behave quite differently in the non-faradic reaction of ion sorption/desorption on the electrode surface.

• Research Organization: Pacific Northwest National Laboratory (PNNL), Richland, WA (US), Environmental Molecular Sciences Laboratory (EMSL)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC05-76RL01830
• OSTI ID: 1243182
• Report Number(s): PNNL-SA-107032; 44591; 400403809
• Journal Information: Journal of Power Sources, Journal Name: Journal of Power Sources Vol. 306; ISSN 0378-7753
• Publisher: Elsevier
• Country of Publication: United States
• Language: English

Related Subjects

Environmental Molecular Sciences Laboratory