Compatibility of Li[sub 7]La[sub 3]Zr[sub 2]O[sub 12] Solid Electrolyte to All-Solid-State Battery Using Li Metal Anode

Electrochemical properties of (LLZ) were investigated to reveal its availability as a solid electrolyte for all-solid-state rechargeable batteries with a Li metal anode. After calcination at , a well-sintered LLZ pellet with a garnet-like structure was obtained, and its conductivity was at room temperature. The cyclic voltammogram of the Li/LLZ/Li cell showed that the dissolution and deposition reactions of lithium occurred reversibly without any reaction with LLZ. This indicates that a Li metal anode can be applied for an LLZ system. A full cell composed of a configuration was also operated successfully at expected voltage estimated from the redox potential of Li metal and . Simultaneously, an irreversible behavior was observed at the first discharge and charge cycle due to an interfacial problem between and LLZ. The discharge capacity of the full cell was . These results reveal that LLZ is available for all-solid-state lithium batteries.