Enhanced Critical Current Density in the Garnet Oxide Electrolyte by a Silver Interlayer

Ta-doped Li_6.4La₃Zr_1.4Ta_0.6O₁₂ (LLZTO) for solid-state lithium batteries demonstrates encouraging performance; however, they encounter issues with lithium dendrite formation that impede their widespread use. Herein, we design a LLZTO ceramic with an interlayer containing a mixed dense layer of Ag and LLZTO, prepared by one-step sintering. The Ag-rich interlayer in LLZTO can hinder the growth and the penetration of lithium dendrites though the reaction between Ag and lithium metal. Compared with the Ag-free counterpart, a higher critical current density of 0.6 mA cm^-2, in addition to a longer life span under a current density of 0.2 mA cm^-2, is achieved by adopting the interlayer in LLZTO. This research offers novel insights into the engineering of garnet-based solid electrolytes, tailored for the advancement of high-rate lithium metal batteries.