Self-organized hetero-nanodomains actuating super Li+ conduction in glass ceramics

Easy-to-manufacture Li 2 S-P 2 S 5 glass ceramics are the key to large-scale all-solid-state lithium batteries from an industrial point of view, while their commercialization is greatly hampered by the low room temperature Li + conductivity, especially due to the lack of solutions. Herein, we propose a nanocrystallization strategy to fabricate super Li + -conductive glass ceramics. Through regulating the nucleation energy, the crystallites within glass ceramics can self-organize into hetero-nanodomains during the solid-state reaction. Cryogenic transmission electron microscope and electron holography directly demonstrate the numerous closely spaced grain boundaries with enriched charge carriers, which actuate superior Li + -conduction as confirmed by variable-temperature solid-state nuclear magnetic resonance. Glass ceramics with a record Li + conductivity of 13.2 mS cm −1 are prepared. The high Li + conductivity ensures stable operation of a 220 μm thick LiNi 0.6 Mn 0.2 Co 0.2 O 2 composite cathode (8 mAh cm −2 ), with which the all-solid-state lithium battery reaches a high energy density of 420 Wh kg −1 by cell mass and 834 Wh L −1 by cell volume at room temperature. These findings bring about powerful new degrees of freedom for engineering super ionic conductors. The development of Li2S-P2S5 glass ceramics is greatly hampered by the low room temperature lithium conductivity. Here, the authors propose a nanocrystallization strategy to fabricate super lithium conductive glass ceramics.