High-rate performance solid-state lithium batteries achieved by infiltrating a single-layer LLZO scaffold

Ceramic-based lithium metal batteries widespread application is limited by the persistent difficulty in achieving stable performance under high c-rate conditions. Herein, we designed flat, thin (∼200 μm) Li 6.45 Al 0.05 La 3 Zr 1.6 Ta 0.4 O 12 single-layer 3D porous scaffolds by the tape-casting technique. Leveraging a meticulously engineered single-layer scaffold, lithium metal is uniformly infiltrated to an average thickness of 35 μm, ensuring seamless interfacial contact. Concurrently, a solid polymer electrolyte is integrated, facilitating the formation of a robust composite solid polymer-garnet separator with a precise thickness of 165 μm, all within a unified structural framework. The integrated single-framework not only reinforces structural and interfacial stability of the metallic anode but also facilitates rapid Li + transport, markedly enhancing ionic conductivity. This synergistic effect enables exceptionally high-rate performance, paving the way for more efficient and reliable electrochemical applications. Full cells with lithium iron phosphate cathode and the Li-infiltrated single-layer ceramic/polymer electrolyte cycled at record current rates of 2C and 5C at room temperature and achieved 100 % capacity retention for 30 cycles at 0.1C. The discharge specific capacities at 2C and 5C are 106.4 and 76.7 mAh g −1 , respectively. This innovative single-layer framework is designed to enable high-current-density, room-temperature solid-state lithium-metal batteries while eliminating the need for stacking pressure. • Single-layer LLZO (Li 6.45 Al 0.05 La 3 Zr 1.6 Ta 0.4 O 12 ) scaffold is prepared by tape casting. • Lithium metal was infiltrated into the single-layer scaffold's interconnected pores. • A solid garnet-polymer separator is fabricated within unified framework. • Solid-state full cell with LiFePO 4 exhibits capacity 106.7 (2C) and 76.7 mAh g −1 (5C).