Na3V2(PO4)3-Graphene Nanocomposite As Stable Cathodes for Na-Ion Batteries

Tuesday, 7 October 2014: 14:40
Sunrise, 2nd Floor, Star Ballroom 2 (Moon Palace Resort)
X. Li, J. Liu (Pacific Northwest National Laboratory), C. Wang (Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory), D. Choi, W. Wang, and V. Sprenkle (Pacific Northwest National Laboratory)


Na-ion batteries, because of the high abundance and uniform geographic distribution of Na sources, have been regarded as low cost and high efficiency energy storage devices for stationary applications.1-2 However, it is difficult to find high energy and stable cathode materials for reversible Na ion insertion and extraction because of the large radius of Na ions (~40% larger than Li ions). Recently, layer structured metal oxides and NASICON structured Na3V2(PO4)3 have been demonstrated to be good cathode candidates.1-7 Na0.44MnO2 is known to have excellent cycling stability and can have a theoretical capacity of ~120 mAh/g when it cycles between Na0.22MnO2 and Na0.66MnO2. However, it has to be pre-cycled to 2V in order to fully use the capacity. Na3V2(PO4)3 is at discharge state and has a theoretical capacity of ~117 mAh/g. Yet it suffers from a low conductivity and usually needs large amount of carbon in electrode preparation. In this work, we synthesized Na3V2(PO4)3-graphene nanocomposite and demonstrated its excellent cycling stability and rate performance as cathodes for Na-ion batteries. A capacity of ~102 mAh/g was obtained at 0.5C current density and the capacity retention was ~99% after 600 cycles.

Results and Discussion


The Na3V2(PO4)3-graphene nanocomposite has 10% graphene. It was mixed with conductive carbon (10%) and binder (10%) and casted on an aluminum substrate. Long cycle stability was demonstrated in coin cells with Na metal as the counter electrode. A capacity of ~102 mAh/g was obtained at 0.5C and the capacity retention was ~99% after 600 cycles. We also studied the rate performance. The capacity at 2C rate is ~70 mAh/g.

 Fig. 1.  Long term cycling stability of the Na3V2(PO4)3-graphene nanocomposite.




The authors would like to acknowledge financial support from the U.S. Department of Energy’s (DOE’s) Office of Electricity Delivery & Energy Reliability (OE) (under Contract No. 57558). We also are grateful for enlightening discussions with Dr. Imre Gyuk of the DOE-OE Grid Storage Program. (A portion of) The research was performed using EMSL, a national scientific user facility sponsored by the Department of Energy's Office of Biological and Environmental Research and located at Pacific Northwest National Laboratory.



  1. 1.       MD Slater, DH Kim, EJ Lee, and CS Johnson. Adv. Funct. Mater. 23(2013):947.
  2. 2.       HL Pan, Y-S Hu, and LQ Chen. Energy Environ. Sci. 6 (2013): 2338.
  3. 3.       YL. Cao, LF Xiao, W Wang, DW Choi, ZM Nie, JG Yu, LV Saraf, ZG Yang, and J Liu. Adv. Mater. 23 (2011): 3155.
  4. 4.       D Kim, E Lee, M Slater, W Lu, S Rood, and CS Johnson. Electrochem. Commun. 18(2012 ): 66.
  5. 5.       M Sathiya, K Hemalatha, K Ramesha, JM Tarascon, AS Prakash. Chem. Mater. 24(2012):1846.
  6. 6.       ZL Jian, WZ Han, X Lu, HX Yang, YS Hu, J Zhou, ZB Zhou, JQ Li, W Chen, DF Chen, and LQ Chen. Adv. Engery Mater. 3(2013):156.
  7. 7.       K Saravanan, CW Mason, A Rudola, KH Wong, and P Balaya. Adv. Energy Mater. 3(2013): 444.