Solution Combustion Synthesis and Electrochemical Characterization of Mixed-Anion Phosphates As Electrode Material for Na-Ion Batteries

Wednesday, 4 October 2017
Prince George's Exhibit Hall D/E (Gaylord National Resort and Convention Center)
S. Ryu (Korea Advanced Institute of Science and Technology), Y. H. Jung (Pohang Accelerator Laboratory), J. E. Wang, J. H. Kim, and D. K. Kim (Korea Advanced Institute of Science and Technology)
Low cost with wide availability of sodium resources makes Na-ion battery (NIB) a promising alternative to energy storage system (ESS) for Li-ion technology. For grid applications, ESS requires large storage capacity, high power density and long lifetime of batteries. In this regard, polyanion-type based materials with the 3-D framework structure have attracted much attention due to high operating voltage and structural stability. Among the various polyanion-type materials, a mixed-anion phosphate is known to have a high power, small volume change and high thermal stability properties. However, these phosphates synthesized by solid state process have limitations such as poor electronic conductivity and sluggish kinetics of the electrochemical reaction.

In this study, solution combustion synthesis (SCS) of nano-sized Na4Mn3(PO4)2(P2O7) and its electrochemical properties are reported. The structure and the phase stability was confirmed by powder X-ray diffraction (XRD). The morphological changes were further characterized using scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The electrochemical performance of nano-sized Na4Mn3(PO4)2(P2O7) was evaluated using cyclic voltammetry and galvanostatic charge-discharge cycling. Nano-sized Na4Mn3(PO4)2(P2O7) electrodes exhibit better electrochemical performance than that of micro-sized particles obtained by solid state method. A complete physico-chemcial and electrochemical characterization of nano-sized Na4Mn3(PO4)2(P2O7) will be discussed in detail.