Robust interface and reduced operation pressure enabled by co-rolling dry-process for stable all-solid-state batteries
Dong Ju Lee, Yuju Jeon, Jung-Pil Lee, Lanshuang Zhang, Ki Hwan Koh, Feng Li, Anthony U. Mu, Junlin Wu, Yuting Chen, Steven G. McNulty, Wei Tang, Marta Vicencio, Dapeng Xu, Ji Young Kim, Zheng Chen
Abstract
Abstract The dry-process is a sustainable and promising fabrication method for all-solid-state batteries by eliminating solvents. However, a pragmatic fabrication design for thin and robust solid-state electrolyte (SSE) layers has not been established. Herein, we report a dry-process approach that enhances mechanical stability of SSE layers from film fabrication to cell operation. By co-rolling thick SSE and positive electrode feeds, a uniform, thin SSE layer (50 µm) and a high loading positive electrode layer (5 mAh cm −2 ) with high active material ratio (80 wt%) are simultaneously achieved. This SSE-positive electrode integrated film exhibits enhanced physical properties and cyclability (> 80% retention after 500 cycles) at low stack pressure (2 MPa) compared to the freestanding counterparts, attributed to reinforced and intimate SSE-positive electrode interface constructed during co-rolling process. Additionally, an all-solid-state pouch cell with high stack-level specific energy (310 Wh kg −1 ) and energy density (805 Wh L −1 ) operating at 30 °C and 5 MPa is demonstrated.