Interfacial Modulation of Nano Li₇La₃Zr₂O₁₂ Composite Electrolytes Prepared by Solvent-free Method

Solid-state batteries (SSBs) with high safety are promising for the energy fields, but the development has long been limited by machinability and interfacial problems. Hence, self-supporting , flexible Nano LLZO CSEs are prepared with a solvent-free method at 25 ℃ . The 99.8 wt% contents of Nano LLZO particles enable the Nano LLZO CSEs to maintain good thermal stability while exhibiting a wide electrochemical window of 5.0 V and a high Li⁺ transfer number of 0.8 . The mean modulus reaches 4376 MPa. Benefiting from the interfacial modulation , the Li|Li symmetric batteries based on the Nano LLZO CSEs show benign stability with lithium at the current densities of 0.1 mA cm^-2 , 0.2 mA cm^-2 , and 0.5 mA cm^-2 . In addition, the Li|LiFePO₄ (LFP) SSBs achieve favorable cycling performance: the specific capacity reaches 128.1 mAh g^-1 at 0.5 C rate, with a capacity retention of about 80% after 600 cycles . In the further tests of the LiNi_0.8Co_0.1Mn_0.1O₂ (NCM811) cathodes with higher energy density, the Nano LLZO CSEs also demonstrate good compatibility: the specific capacities of NCM811-based SSBs reach 177.9 mAh g^-1 at 0.5 C rate, while the capacity retention is over 96% after 150 cycles . Furthermore, the Li|LFP soft-pack SSBs verify the safety characteristics and the potential for application, which have a desirable prospect.