Figure 1 : Schematic of the lithiation process in various sulphur-based nanostructure morphologies.

From: Sulphur–TiO2 yolk–shell nanoarchitecture with internal void space for long-cycle lithium–sulphur batteries

Figure 1

(a) Bare sulphur particles undergo large volumetric expansion and polysulphide dissolution upon lithiation, resulting in rapid capacity decay and low Coulombic efficiency. (b) Although the core–shell morphology provides a protective coating, cracking of the shell will occur upon volume expansion of sulphur during lithiation, leading to polysulphide dissolution as well. (c) The yolk–shell morphology provides internal void space to accommodate the volume expansion of sulphur during lithiation, resulting in a structurally intact shell for effective trapping of polysulphides.