An Ultrahigh Capacity Graphite/Li₂S Battery with Holey-Li₂S Nanoarchitectures.

ABSTRACT: The pairing of high-capacity Li₂S cathode (1166 mAh g^-1) and lithium-free anode (LFA) provides an unparalleled potential in developing safe and energy-dense next-generation secondary batteries. However, the low utilization of the Li₂S cathode and the lack of electrolytes compatible to both electrodes are impeding the development. Here, a novel graphite/Li₂S battery system, which features a self-assembled, holey-Li₂S nanoarchitecture and a stable solid electrolyte interface (SEI) on the graphite electrode, is reported. The holey structure on Li₂S is beneficial in decomposing Li₂S at the first charging process due to the enhanced Li ion extraction and transfer from the Li₂S to the electrolyte. In addition, the concentrated dioxolane (DOL)-rich electrolyte designed lowers the irreversible capacity loss for SEI formation. By using the combined strategies, the graphite/holey-Li₂S battery delivers an ultrahigh discharge capacity of 810 mAh g^-1 at 0.1 C (based on the mass of Li₂S) and of 714 mAh g^-1 at 0.2 C. Moreover, it exhibits a reversible capacity of 300 mAh g^-1 after a record lifecycle of 600 cycles at 1 C. These results suggest the great potential of the designed LFA/holey-Li₂S batteries for practical use.

SUBMITTER: Ye F 

PROVIDER: S-EPMC6051237 | biostudies-literature | 2018 Jul

REPOSITORIES: biostudies-literature