Sub-10 nm V2O5 Crystals on Carbon Nanosheets for Advanced All-Solid-State Lithium Metal Batteries

V 2 O 5 , as a lithium-free cathode material, has inherent defects such as sluggish kinetics and volume change and, at the same time, requires a lithium metal anode that tends to form dendrites in liquid electrolytes. Both the lithium dendrite and the flammable electrolyte solvent bring longtime safety issues. This work introduces nonflammable inorganic–organic composite solid electrolyte to inhibit the growth of the lithium dendrite and suppress the instability caused by V 2 O 5 nanometerization. However, the long-term cycling and rate performances are still insufficient even when reducing V 2 O 5 size to about 50 nm. As an improvement, sub-10 nm V 2 O 5 /C nanosheets are designed and prepared using corn stalks as precursors through simple impregnation and calcination process. The V 2 O 5 /C offers a much better electrode/electrolyte contact and interface stability than bulk V 2 O 5 and commercial V 2 O 5 in the inorganic–organic composite solid electrolyte. The discharge capacity is 228 mAh g −1 at 0.1 C after 50 cycles and ≈110 mAh g −1 at 2.0 C.