Lithium Intercalation Layer Eliminate Dendrite to Achieve Stable Long-Life Lithium-Sulfur Battery

Abstract

High energy density battery technology for portable electronics and grid energy system are in high demand. Lithium anode considered as the suitable electrode for commercialization of lithium-ion battery because of having highest specific capacity, lowest reduction potential and low density. However, uncontrolled lithium dendrite growth results in low coulombic efficiency, internal short-circuit of the cells. Here, we demonstrate δ-CsPbI3 as a protective layer for lithium metal anode fabricated by a low-cost, facile spray coating methodology. Furthermore, experimental and density function theory study confirms the lithium ion intercalate in the crystal structure of δ-CsPbI3. Lithium intercalation into δ-CsPbI3 fast the lithium ion migration, stabilize the electrodeposition and maintain the integrity of SEI layer. We observe a dendrite free plating for 1000 hours at a current density of 1 mA cm-2 and discharge capacity of 1 mAh cm-2. We achieve a starting discharge capacity of 823 mAh g-1 and coulombic efficiency of ⁓100% throughout 1000 cycles with decay rate of ⁓0.035% per cycle in a Li-Sulfur full cell configuration. Our new concept accomplish a stable lithium metal for future commercialization and open up new area of research to achieve safe lithium anode.