Modified Separator with Nitrogen‐doped High‐graphitized Carbon for Lithium‐sulfur Batteries

Abstract

Suppressing the shuttling of dissolved lithium polysulfides (LiPSs) is an indispensable strategy to extend the cycling life of lithium-sulfur (LiÀ S) batteries. One strategy is absorbing the LiPSs by modifying separator of LiÀ S batteries. Herein, we show a novel nitrogen-doped graphitized carbon (NGC) derived from coconut shell, which was annealed by flash Joule heating at ultrahigh temperature within seconds. The NGC was coated on the polypropylene (PP) separator to prepare the modified PP separator, which enabled the LiÀ S batteries to work stably at 1 C with a low fading rate of 0.09 % from 788 mAh g À 1 . Microscopy analysis and Raman spectrum reveal that the high-graphitization carbon with heavily nitrogen-doping strengthens the adsorption of LiPSs in the charge/ discharge process.

Coaxial Electrospun Tai Chi-Inspired Lithium-Ion Battery Separator with High Performance and Fireproofing Capacity

“…The surface of the TPP@PVDF/SiO 2 /GO separator before and after combustion was analyzed by Raman spectroscopy, as shown in Figure c. The Raman peaks at 1252 cm –1 (D) and 1500 cm –1 (G) indicated that amorphous and graphitized carbon coexisted in the surface . The intensity ratio of the D side to the G side ( I G / I D ) indicated the degree of graphitization ( S ) .…”

“…The Raman peaks at 1252 cm −1 (D) and 1500 cm −1 (G) indicated that amorphous and graphitized carbon coexisted in the surface. 58 The intensity ratio of the D side to the G side (I G /I D ) indicated the degree of graphitization (S). 10 The S values of the composite membrane before and after combustion were 0.926 and 1.248, respectively.…”

Defect engineering in carbon materials for electrochemical energy storage and catalytic conversion

“…Integration of defect-rich carbon and commercial separator is an efficacious and practicable strategy. Wei et al 244 and lower decomposition energy barrier of Li2S, thus giving combed separator higher catalytic activity and faster conversion (Fig. 10c-10f).…”

“…Integration of defect-rich carbon and a commercial separator is an efficacious and practicable strategy. Wei et al 238…”

“…Integration of defect-rich carbon and a commercial separator is an efficacious and practicable strategy. Wei et al 238 prepared N-doped graphitized carbon (NGC) derived from coconut shell to modify the PP separator. NGC has evenly distributed N elements of about 4.7 wt%, which offers strong adsorption and catalytic site for polysulfides.…”