All-Solid-State Rechargeable Lithium Metal Battery with a Prussian Blue Cathode Prepared by a Nonvacuum Coating...

A Prussian blue LiFeFe(CN)₆ thin-film cathode is fabricated by a nonvacuum coating technology without post-annealing process. The thin film of the solid electrolyte lithium phosphorus oxynitride (LiPON) is deposited onto the cathode by using radio-frequency magnetron sputtering. Then, the lithium metal anode is deposited on the LiPON film by the thermal evaporation method to fabricate the all-solid-state LiFeFe(CN)₆/LiPON/Li battery with a thickness of 16 μm and a size of ∼10 cm². Electrochemical properties of LiFeFe(CN)₆/LiPON/Li battery are first investigated at various temperatures from -30 to 80 °C. Our results demonstrated that the all-solid-state LiFeFe(CN)₆/LiPON/Li battery exhibits a discharge capacity of 82.5 mA h/g for the third cycle at 60 °C and shows stable cyclic performance within 200 cycles. These results provide the feasibility to assemble an all-solid-state lithium-ion battery by combining nonvacuum and vacuum techniques through an environmentally friendly process at low temperature.