Effect of temperature on the performances and in situ polarization analysis of zinc-nickel single flow batteries

The recently proposed high power density zinc-nickel single flow batteries (ZNBs) exhibit great potential for larger scale energy storage. The urgent needs are in the research into temperature adaptability of ZNBs before practical utilization. Furthermore, making clear their polarization distribution is essential to direct the further improvement of battery performance. Here, we focus on the trends in the polarization distribution and effect of temperature on the performance of ZNBs. The result shows that ZNBs can operate in the temperature range from 0 degrees C to 40 degrees C with acceptable energy efficiency (53%-79.1%) at 80 mA cm(-2). The temperature sensitivity of coulombic efficiency and energy efficiency are 0.65% degrees C-1 and 0.98% degrees C-1 at 0 degrees C-20 degrees C, respectively. The positive polarization is much larger than the negative polarization at all studied temperatures. The charge overpotential of the positive electrode is more sensitive to temperature. These results enable us to better evaluate the application prospect of ZNBs and point a clear struggling orientation to further improve the battery performance. (C) 2013 Elsevier B.V. All rights reserved.