Powering Lithium–Sulfur Battery Performance by Propelling Polysulfide Redox at Sulfiphilic Hosts

• DOI: 10.1021/acs.nanolett.5b04166
• Publication Date: 2015-12-29T17:06:55Z
• Authors: Zhe Yuan; Hong-Jie Peng; Ting-Zheng Hou; Jia-Qi Huang; Cheng-Meng Chen; Dai-Wei Wang; Xin-Bing Cheng; Fei Wei; Qiang Zhang
• Keywords: Polysulfide; Lithium–sulfur battery

Lithium–sulfur (Li–S) battery system is endowed with tremendous energy density, resulting from the complex sulfur electrochemistry involving multielectron redox reactions and phase transformations. Originated slow kinetics of polysulfide intermediates, flood polysulfides in batteries during cycling induced low utilization, severe polarization, efficiency, deteriorated shuttle, short life. Herein, sulfiphilic cobalt disulfide (CoS2) was incorporated into carbon/sulfur cathodes, introducing strong interaction between lithium CoS2 under working conditions. The interfaces electrolyte served as adsorption activation sites for polar therefore accelerated polysulfides. high reactivity not only guaranteed effective polarization mitigation promoted efficiency by 10% but also promised discharge capacity stable performance 2000 cycles. A decay rate 0.034%/cycle at 2.0 C a initial 1368 mAh g–1 0.5 were achieved. Since propelling reaction limited to Li–S system, we foresee reported strategy herein can be applied other high-power devices through systems controllable reactions.