Composite polymer electrolyte with high inorganic additive contents to enable metallic lithium anode

Composite polymer electrolytes (CPE) are a very promising strategy for using lithium metal anodes safely. These electrolytes are formed by polymeric matrices in which ceramic nanoparticles are incorporated to modify their mechanical and conduction properties. In this work a methacrylate-based polymer matrix containing 63 wt% of ZrO2 nanoparticles (NPs) was prepared and tested as electrolyte for lithium metal batteries. The prepared CPE shows a higher ionic conductivity than the polymer matrix without ZrO2 NPs and a higher lithium transport number than Celgard with liquid electrolyte and stabilizes the processes of deposition-dissolution of lithium with respect to the reference cell, thus prolonging the cycling time without short circuits. Finally, the compatibility of the CPE with a LiFePO4 cathode was verified, achieving a stable cycling at 1.0 C and at ambient temperature, with an impressive capacity of 140.18 mAh g−1 even after 250 cycles.