Evolutionary Design of Low Molecular Weight Organic Anolyte Materials for Applications in Nonaqueous Redox Flow Batteries

Christo S. Sevov, Rachel E.M. Brooner, Etienne Chénard, Rajeev S. Assary, Jeffrey S. Moore, Joaquín Rodríguez-López, Melanie S. Sanford

Research output: Contribution to journalArticlepeer-review

Abstract

The integration of renewable energy sources into the electric grid requires low-cost energy storage systems that mediate the variable and intermittent flux of energy associated with most renewables. Nonaqueous redox-flow batteries have emerged as a promising technology for grid-scale energy storage applications. Because the cost of the system scales with mass, the electroactive materials must have a low equivalent weight (ideally 150 g/(mol·e-) or less), and must function with low molecular weight supporting electrolytes such as LiBF4. However, soluble anolyte materials that undergo reversible redox processes in the presence of Li-ion supports are rare. We report the evolutionary design of a series of pyridine-based anolyte materials that exhibit up to two reversible redox couples at low potentials in the presence of Li-ion supporting electrolytes. A combination of cyclic voltammetry of anolyte candidates and independent synthesis of their corresponding charged-states was performed to rapidly screen for the most promising candidates. Results of this workflow provided evidence for possible decomposition pathways of first-generation materials and guided synthetic modifications to improve the stability of anolyte materials under the targeted conditions. This iterative process led to the identification of a promising anolyte material, N-methyl 4-acetylpyridinium tetrafluoroborate. This compound is soluble in nonaqueous solvents, is prepared in a single synthetic step, has a low equivalent weight of 111 g/(mol·e-), and undergoes two reversible 1e- reductions in the presence of LiBF4 to form reduced products that are stable over days in solution.

Original languageEnglish (US)
Pages (from-to)14465-14472
Number of pages8
JournalJournal of the American Chemical Society
Volume137
Issue number45
DOIs
StatePublished - Oct 28 2015

ASJC Scopus subject areas

  • Catalysis
  • Chemistry(all)
  • Biochemistry
  • Colloid and Surface Chemistry

Fingerprint Dive into the research topics of 'Evolutionary Design of Low Molecular Weight Organic Anolyte Materials for Applications in Nonaqueous Redox Flow Batteries'. Together they form a unique fingerprint.

Cite this