Investigation of Polyanion Materials with Multiple Intercalation Cations: Na Ions in Na-Ion Full Cell

Wednesday, 4 October 2017
Prince George's Exhibit Hall D/E (Gaylord National Resort and Convention Center)
E. Paharik, K. Rudman, and G. Koenig (University of Virginia)
As the market for secondary batteries increases to include electric vehicles, load-leveling systems, and storage for intermittent energy generation, significant battery research has been directed towards improving battery safety, reliability, robustness, and cost. Replacing the LiCoO2 cathode with less expensive and more environmentally friendly manganese or iron based materials has been one research direction aimed at meeting some of these goals. In addition, alternative earth abundant cations such as Na+ or Mg++ as the intercalation species would also be an attractive battery option. Phosphate polyanion materials are promising low cost active materials due to their high thermal stability and reasonable gravimetric capacities, and are suitable for use in both aqueous and organic electrolytes and with a variety of intercalation ions due in part to their open framework structures. Herein, we examine the electrochemical behavior of a variety of phosphate polyanion batteries within a suite of different electrolytes for systematic investigations of the electrochemical behavior of the polyanion compounds with different intercalation cations. Electrochemical characterization will be described for phosphate polyanion structures, particularly Ti and Fe based NASICON structured materials, within electrolytes containing a variety of cation species.