LISICON-Based Amorphous Oxide for Bulk-Type All-Solid-State Lithium-Ion Battery

The use of oxide electrolytes promises the safety of Li-ion batteries but complicates the fabrication of electrochemical interfaces. Herein, we report the facile preparation of ionic-transferable interfaces between the electrode and electrolyte in oxide-based bulk-type all-solid-state lithium-ion batteries (ASS-LIBs) owing to the deformability of the LISICON–Li3BO3 amorphous oxide, which cannot be realized with currently popular crystalline oxide electrolytes. The amorphous oxide was used to assemble an ASS-LIB even without firing. Moreover, low-temperature heat treatment with a spark-plasma sintering process effectively enhanced the charge–discharge performance of the ASS-LIB: the amorphous oxide was further densified until colorless, and re-formation of a nanosized LISICON crystalline phase in the oxide–electrolyte matrix occurred. The interfacial formability provided by the LISICON–Li3BO3 amorphous oxide is an effective route for the successful design of bulk-type oxide-based ASS-LIBs.