Polymer-based supercapacitors (PSCs) have the potential for large-scale practical application because of their high theoretical capacitance. The effect of environmental temperature on the practical applications of PSCs and its underlying mechanism has been long neglected. In this work, a graphene-silver-polypyrrole nanocomposite was prepared by an eco-friendly hydrothermal in situ polymerization method at temperatures ranging from -45 degrees C to 80 degrees C. The ternary hybrid nanocomposites exhibited a high specific capacitance of 611.5 F g(-1)/586 F g(-1) at a current density of 1.0 A g(-1) and a remarkable cycling stability of 93% and 82.4% capacitance retention after 3000 cycles at -45 degrees C and 80 degrees C, respectively. Furthermore, they also achieved excellent flexibility in a wide temperature range as all-solid-state supercapacitors. The outstanding electrochemical performance of the graphene-silver-polypyrrole supercapacitors in such a wide temperature range exceeds that of similar polypyrrole-based super capacitors reported previously. (C) 2017 Elsevier B.V. All rights reserved.