Garnet Based Li-Metal Batteries

Abstract

Metallic lithium metal is considered the “Holy Grail” for high-energy density batteries. However, using lithium metal in organic liquid electrolyte systems faces many challenges in terms of both battery performance and safety. A fundamental strategy is to develop a solid-state electrolyte (SSE) to mechanically suppress lithium dendrites and intrinsically eliminate SEI formation. Meanwhile, numerous solid-state inorganic Li+ electrolytes are being investigated to replace liquid organic LIB electrolytes and enable Li metal anode. Due to their high ion conductivity and excellent stability, Li-stuffed garnets are particularly attractive, which exhibit the most promising physical and chemical properties for SSEs. However, major challenges still exist in garnet based electrolytes, including: (1) Being either too thick with corresponding high ASR or too mechanically fragile when thin (~20 μm); (2) High temperature processing that is incompatible with most anode/cathode materials; and (3) High interfacial impedance for cell operations. In this talk, I will discuss our recent research progress on Li metal batteries with garnet electrolytes, including: (1) interface layer treatments to improve the wetting between Li metal anode and garnet electrolytes, and stabalize Li metal-garnet interface; (2) Garnet nanofibers that allows the development of flexible, all solid state electrolyte. I will also breiflydiscuss cell integrations and performance.