Dielectric Relaxation Behavior of a Poly(ethylene carbonate)‐Lithium Bis‐(trifluoromethanesulfonyl) Imide Electrolyte

• DOI: 10.1002/macp.201500125
• Publication Date: 2015-07-06T19:10:57Z
• Authors: Joh Motomatsu; Hidekazu Kodama; Takeo Furukawa; Yoichi Tominaga
• Keywords: Imide

A new class of polymer electrolytes, consisting poly(ethylene carbonate) (PEC) and metal salts, is expected to find application in all‐solid‐state batteries because its excellent performance as an electrolyte. To study the ion‐conductive mechanism PEC‐based broadband dielectric spectroscopy used analyze correlation between relaxation ionic conduction PEC‐lithium bis‐(trifluoromethanesulfonyl) imide electrolytes over a broad range salt concentration (0–150 mol%) at 40 °C. The PEC system has two modes, α β , associated respectively with segmental motion local chains. conductivity increases exponentially increasing concentration, while frequency ( f ) decreases strength (Δ ε low concentrations, whereas contrast Δ being saturated high concentrations above 10 mol%. It believed that mobility segment enhanced by factors. first intermolecular interactions decrease, given existence many ion pairs aggregated ions around domains where dissociated are highly concentrated. second intramolecular CO CH 2 lowered ion–dipole interaction. image