All-solid-state lithium secondary battery with ceramic/polymer composite electrolyte

Dense lithium lanthanum titanate, (Li,La)TiO3, pellets were prepared using a spark-plasma sintering (SPS) method. The obtained (Li,La)TiO3 pellets showed relatively high lithium ion conductivity, typically 10−3 S cm−1 at 22 °C, with an activation energy of 30.1 kJ mol−1. Lithium manganese oxide, LiMn2O4, was deposited on (Li,La)TiO3 pellets by an electrostatic spray deposition (ESD) method at 400 °C without significant formation of by-products at the interface (Li,La)TiO3/LiMn2O4. An all-solid-state battery system, LiMn2O4/(Li,La)TiO3/SPE/Li, where a solid polymer electrolyte (SPE) was sandwiched between (Li,La)TiO3 and Li, showed good charge/discharge characteristics over 100 cycles at 60 °C.