Long Cycle Life Organic Polysulfide Catholyte for Rechargeable Lithium Batteries.

ABSTRACT: Organic compounds with active sites for lithiation can be used as electrode materials for lithium batteries. Their tunable structures allow a variety of materials to be made and investigated. Herein, a spectrum of dipyridyl polysulfides (Py2S x , 3 ≤ x ≤ 8) is prepared in electrolyte by a one-pot synthesis method from dipyridyl disulfide (Py2S2) and elemental sulfur. It renders up to seven dipyridyl polysulfides (i.e., Py2S3, Py2S4, Py2S5, Py2S6, Py2S7, and Py2S8) which show fully reversible electrochemical behavior in lithium batteries. In the discharge, the initial lithiation occurs at 2.45 V leading to the breakage of Sα-Sβ bonds in Py2S x and formation of lithium 2-pyridinethiolate, in which lithium is coordinated in between N and S atoms. The left sulfur species act as elemental sulfu

SUBMITTER: Wang DY 

PROVIDER: S-EPMC7029628 | biostudies-literature | 2020 Feb

REPOSITORIES: biostudies-literature