Thin-film Materials for Solid-State Rechargeable Lithium Batteries

摘要

Thin-film materials for solid-state rechargeable lithium batteries were fabricated by physical vapor deposition. The cathode is a lithium cobalt oxide (LiCoO_2) film, separated from the anode (metallic lithium) by an electrolyte of lithium phosphorus oxynitride (LiPON). The LiCoO_2 was deposited by RF sputtering, annealed after deposition and x-ray diffraction patterns showed higher crystallinity with 2 hours of annealing in vacuum with a temperature of 650 °C. LiPON was deposited by reactive RF sputtering (nitrogen) and metallic lithium by thermal evaporation. Ionic conductivity of LiPON films was measured at room temperature of 26 °C and 6.3×10~(-7) S.cm~(-1) obtained. Electrical resistivity of a 3 μm thickness lithium film was 7.6×10~(-8) Ω.m, measured during deposition.