Ion-conductive behavior of a novel polymer electrolyte without oxyethylene units, poly(ethylene carbonate) (PEC)-Li salt system, was reported. Salt-concentration dependence revealed that the LiCF3SO3 and LiClO4 electrolytes exhibit typical polyether-like conduction behavior. However, the LiBETI, LiBF4 and LiTFSI electrolytes were much different, and the conductivity increased and Tg decreased with increasing salt concentration. This behavior of salt-rich PEC electrolytes relates to the ‘polymer-in-salt’ system. Li+ transference number of PEC-LiBF4 (44.4 wt%) electrolyte was measured, and the value was estimated to be ∼0.5 at 100 oC.
- Yoichi Tominaga
- Vannasa Nanthana
- Daichi Tohyama