Samsung Advanced Institute of Technology

Anode-free (or Li-metal free) batteries with garnet-type solid-state electrolytes are considered a promising path in the development of safe and high energy-density batteries. However, their practical implementation has been hindered by the internal strain that arises from the repeated plating and stripping of Li metal at the interlayer between the solid electrolyte and negative electrode. Herein, we utilize the titanium nitrate nanotube (TiN NT) architecture and a Ag-C interlayer to mitigate the anisotropic stress caused by the recurring formation of Li deposition layers during the cycling process. The mixed ionic-electronic conducting nature of the TiN NTs effectively accommodates the entry of reduced Li into its free volume space via interfacial diffusion creep, achieving strain-free operation with nearly tenfold volume suppressing capability compared to a conventional Cu anode counterpart during the lithiation process. Notably, the fabricated Li_6.4La₃Zr_1.7Ta_0.3O₁₂ (LLZTO)-based anode-free solid-state battery full-cell, coupled with a high voltage cathode, exhibits remarkable room temperature (25 ℃) cyclability of over 600 cycles at 1 mA cm^-2 with an average coulombic efficiency of 99.8%.