Facile Formation of a Solid Electrolyte Interface as a Smart Blocking Layer for High‐Stability Sulfur Cathode. Issue 26 (24th April 2017)

• Record Type: Journal Article
• Authors: Guo, Junling; Du, Xinyu; Zhang, Xiaolong; Zhang, Fengxiang; Liu, Jinping
• Is Part Of: Advanced materials. Volume 29:Issue 26(2017)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2017-04-24
• Subjects: lithium polysulfide blocking -- Li–sulfur batteries -- solid electrolyte interfaces; Materials -- Periodicals; Chemical vapor deposition -- Periodicals; 620.11
• DOI: 10.1002/adma.201700273
• Languages: English
• ISSNs: 0935-9648

Abstract

Abstract : The practical application of lithium–sulfur batteries (LSBs) is hindered by their poor cycle life, which stems mainly from the "redox shuttle reactions" of dissolved polysulfides. To develop a high‐performance cathode for LSBs, encapsulation of polysulfides with a blocking layer is potentially straightforward. Herein, a novel strategy is reported encapsulate sulfur and the electrolyte together in porous carbon spheres by using a solid electrolyte interface (SEI) that can selectively sieve Li + ions while efficiently avoiding polysulfide accumulation and suppressing undesired polysulfide migration. This strategy is simple, straightforward, and effective. The carbon/sulfur cathode only needs to be cycled a few times within a voltage window of 0.3–1.0 V to form such a smart SEI, allowing the resulting cathode to exhibit superior stability extending 600 cycles. This strategy can be combined with other existing advanced sulfur cathode designs to improve the overall performance of LSBs. Abstract : A novel solid electrolyte interface (SEI) blocking layer is facilely developed to encapsulate sulfur and the electrolyte together in a porous carbon sphere cathode. The SEI selectively sieves Li + ions while efficiently preventing polysulfide accumulation and suppressing undesired polysulfide migration. With this SEI, the sulfur cathode delivers superior stability, extending 600 cycles, while maintaining a good rate capability.