An integrated optimization strategy by Joule heating technique enabling rapid fabrication of robust Li_1.3Al_0.3Ti_1.7(PO₄)₃ solid-state electrolyte for all-solid-state lithium metal batteries

The advancement of high-energy–density and intrinsically safe all-solid-state lithium metal batteries (ASSLMBs) is crucial for the comprehensive electrification of energy consumption. Nevertheless, intrinsic defects in solid-state electrolytes (SSEs) and suboptimal interfacial contacts often lead to uncontrolled dendritic growth during practical battery operation. To address these challenges, this study proposes an integrated optimization strategy for bulk-phase defects and interfacial contacts of Li_1.3Al_0.3Ti_1.7(PO₄)₃ (LATP) SSEs based on ultra-fast Joule heating sintering (UHS) technique. Introducing specific sintering auxiliaries and a dual-process sintering approach can achieve the rapid densification of LATP SSEs. Additionally, the thermal pulse welding (TPW) technique for the integrated anode/SSE/cathode further provides superior SSE/electrode interface contact, facilitating the in-situ formation of a continuous ion-conducting network for improved electrochemical kinetics. The optimized Li||LATP||NCM811 ASSLMBs demonstrate exceptional specific capacity (185.9 mAh/g at 0.2 C) and robust cycling stability (90.9 % capacity retention after 100 cycles). This integrated optimization strategy can offer a critical technical reference for the rapid fabrication of high-performance ASSLMBs.