Fig. 4: The self-adaptation verification of ULCE toward PANI-V2O5 cathode.

a Current challenge arising in V-based cathode and the mechanism of solidified layer to improve the structural stability. b The concentration of V ions in the electrolyte after 10 cycles with three different types of electrolyte. c The cycling ability of PANI-V2O5 full cell with ULCE at −80 °C. d The capacity ability of PANI-V2O5 full cell with ULCE at various temperatures. e The rate performance of cells with ULCE at −80 °C and f corresponding charge and discharge curves.