Solid-state lithium-metal batteries with solid electrolytes are promising for next-generation energy-storage devices. However, it remains challenging to develop solid electrolytes that are both mechanically robust and strong against external mechanical load, due to the brittleness of ceramic electrolytes and the softness of polymer electrolytes. Herein, a nacre-inspired design of ceramic/polymer solid composite electrolytes with a “brick-and-mortar” microstructure is proposed. The nacre-like ceramic/polymer electrolyte (NCPE) simultaneously possesses a much higher fracture strain (1.1%) than pure ceramic electrolytes (0.13%) and a much larger ultimate flexural modulus (7.8 GPa) than pure polymer electrolytes (20 MPa). The electrochemical performance of NCPE is also much better than pure ceramic or polymer electrolytes, especially under mechanical load. A 5 × 5 cm2 pouch cell with LAGP/poly(ether-acrylate) NCPE exhibits stable cycling with a capacity retention of 95.6% over 100 cycles at room temperature, even undergoes a large point load of 10 N. In contrast, cells based on pure ceramic and pure polymer electrolyte show poor cycle life. The NCPE provides a new design for solid composite electrolyte and opens up new possibilities for future solid-state lithium-metal batteries and structural energy storage.
A.L. and X.L. contributed equally to this work. Y.Y. acknowledges support from the Air Force Office of Scientific Research (FA9550-18-1-0410). The authors greatly appreciate the funding support from the NSF MRSEC program through Columbia in the Center for Precision Assembly of Superstratic and Superatomic Solids (DMR-1420634). A.L. would like to acknowledge the financial support from the China Scholarship Council (No. 201706010086) and X.Y.C. acknowledges the Natural Science Foundation of China (No. 51774016).
- composite electrolytes
- mechanical load
- nacre structure
- solid-state batteries