High Stable Sulfur Cathode with Self‐Healable and Physical Confining Polydimethylsiloxane Interlayer

Abstract

Li‐sulfur (Li−S) batteries are promising high‐performance power sources, but their practical application is significantly impeded by the large volume change and diffusion of polysulfides (i. e., shuttle effect). Here we report that such issues can be effectively addressed by rationally designing a self‐healable and confining interfacial nanolayer. The goal is achieved by encapsulating individual sulfur microparticles with a polydimethylsiloxane (PDMS) nanoshell cross‐linked by dynamic imine bonding. The nanoshell well adapts the volume change, timely remediates itself after breaking, but also in situ confines the generated polysulfides, which ensures a “robust micro‐interface” between each sulfur particle and the electrolyte in the cycling process. Consequently, the resulting sulfur cathodes exhibit excellent energy‐storage performances even at a high sulfur loading. We believed that this design of a multifunctional micro‐interfacial layer provides an alternative insight into the intrinsic problems of sulfur cathodes.

More than Just a Binder: Versatile Block Copolymer Enhances the Electrochemical Performance of a Nickel-Rich Cathode

“…It is rich in aromatic rings and interacts with carbon-conductive agents through π–π stacking. The PDMS blocks can be swollen by the electrolyte solution, and the electrochemical kinetics will be significantly enhanced. ,− Furthermore, both PEI and PDMS blocks exhibit stronger interactions with lithium ions compared to EC, DMC, and PVDF. Therefore, the PEMS binder can effectively tune the solvation structure of lithium ions by expelling EC and DMC molecules from the solvation sheath through which the oxidative decomposition of the electrolyte solvent can be inhibited.…”