Phthalocyanine-based solid-state electrolyte for high-capacity and long-life lithium-ion batteries

A new solid-state electrolyte (SSE) with low energy activation for lithium-ion conduction was designed and tested in an all-solid-state battery configuration with a lithium metal anode and a lithium iron phosphate (LiFePO[Formula: see text] cathode. The aromatic character of the phthalocyanine-based SSE facilitates cell stabilization against lithium metal dendrites, and the low energy of activation enables battery cycling at -20 °C. The use of the phthalocyanine-based SSE necessitated the development of an in-situ process for the formation of an effective solid electrolyte interphase (SEI) layer between the anode and the SSE. Such a procedure enabled battery cycling over a 12-to-16-month time frame. The cells delivered high discharge capacities of up to 291.3 mAh/g at 23 °C and 194.5 mAh/g at -20 °C. All cells were fabricated in a dry room via simple solution casting of the soluble SSE onto either an aerosol-jet-deposited or tape-cast LiFePO 4 cathode.