Improved lithium-metal/vanadium pentoxide polymer battery incorporating crosslinked ternary polymer electrolyte with N-butyl-N-methylpyrrolidinium bis(perfluoromethanesulfonyl)imide

Li metal polymer batteries incorporating crosslinked ternary PEO/PYR14TESI/LiTESI solid polymer electrolyte (SPE) have been prepared, using V2O5 as active cathode material. As a result of the optimization of the SPE as well as the cell assembly and cycling conditions, V2O5 lithium metal polymer batteries allow reaching 796 Wh kg(-1) (of V2O5) at C/10 at 40 degrees C and maintaining 663 Wh kg(-1) after 200 cycles at 40 degrees C. This is higher than the theoretical specific energy of LiCoO2 vs. Li of 609 Wh kg(-1). Cycling at 80 degrees C allows reaching 270 mAh g(-1) at C/2 and 210 mAh g(-1) at 1 C, while at 20 degrees C it is still possible to reach a discharge capacity of almost 100 mAh g(-1) at low rates. Post-cycling SEM and EDX imaging showed that, after 200 cycles at 40 degrees C, if the plating of Li is not fully homogeneous, no sign of dendrite growth nor obvious vanadium dissolution and redeposition on the anode side occurred. (C) 2014 Elsevier B.V. All rights reserved.