An ambient-temperature superionic conductive, electrochemically stable, plastic cross-linked polymer electrolyte for lithium metal battery

A plastic cross-linked polymer is prepared using acrylonitrile as a monomer and poly(ethylene glycol diacrylate) as a linking agent. A phase diagram-guide rational design is introduced to fabricate the polymer composite electrolyte in the case of succinonitrile complexed with lithium bis-trifluoromethanesulfonimide. The plastic cross-linked polymer-based electrolyte films with ambient-temperature superionic conductivity (2.33 mS cm-1) and a wide electrochemical window (0-5.6 V vs. Li/Li+) have been demonstrated. The charging and discharging experiments of the plastic polymer composite electrolyte-based lithium batteries show that the plastic polymer electrolyte can cycle normally and safely at a current density of 0.5 mA cm-2. These batteries exhibit excellent average coulombic efficiency of 98.5% in the first 150 cycles. The initial capacity at 25 degrees C is 127.5 mAh g-1 (0.2 C), which is close to the value achieved by liquid-electrolyte-based cells under similar conditions. The capacity retention is 91% after 150 cycles. An ambient-temperature superionic conductive and plasticized cross-linked acrylate polymer electrolyte film has been prepared successfully. The SPE50 with optimized ionic conductivity (over 2.33 x 10-3 S cm-1), Li+ transference number (0.55) and electrochemical window (reaching 5.6 V) was achieved at room temperature, and the Li/SPE50/LiFePO4 battery exhibits excellent average coulombic efficiency of 98.5% in the first 150 cycles. Preparation and optimization of electrochemically stable superionic polymer-based electrolyte and its battery performance.image