Silkworm Excrement Derived In‐situ Co‐doped Nanoporous Carbon as Confining Sulfur Host for Lithium Sulfur Batteries

Abstract

Lithium sulfur batteries (Li−S) are widely proposed as the next generation energy storage systems due to their super high energy density. However, one of the challenges remains in the “shuttle effects” of polysulfides, which hinders the practical application of Li−S. To address the above issue, herein, we propose an innovative design strategy of in‐situ co‐doped nanoporous carbon (ICPC) derived from silkworm excrement to achieve the strong chemical bonding and strict physical confinement of sulfur. As a result, the migration of polysulfides might be suppressed by the synergistic effects of physical and chemical interactions, which is helpful for the significant improvement of electrochemical performance. After 100 stable cyclic discharge‐charge tests at the current density of 0.2 C, the reversible capacity of the as obtained ICPC−S composite cathode still maintains around 500 mAh g−1, corresponding to 67% capacity retention. More importantly, high Coulombic efficiency of nearly 100% can be realized, suggesting the greatly avoided “shuttle effects”. Such a novel design of in‐situ co‐doped nanoporous carbon opens up new possibilities for high performance lithium sulfur batteries.

Application of Aqueous Saline Process to Extract Silkworm Pupae Oil (Bombyx mori): Process Optimization and Composition Analysis

“…In general, insects and pupae are composites containing proteins, lipids, and polysaccharides. Silkworm pupae have been reported to be 30-55% protein, 10-15% carbohydrates, and 25-30% oil, which is rich in various saturated and unsaturated fatty acids [37][38][39][40][41]. The high protein and fat content of silkworm pupae indicate their extensive potential as an alternative source for food and feed.…”

In‐situ Generated Ultra‐High Dispersion Sulfur 3D‐Graphene Foam for All‐Solid‐State Lithium Sulfur Batteries with High Cell‐Level Energy Density

“…[5][6][7][8] However, LiÀ S batteries still face several inevitable issues, such as the insulating property of sulfur and lithium sulfide, the shuttle effect and volume expansion during cycling, which cause the irreversible loss of active materials. [9][10][11] Replacing liquid electrolyte with solid electrolyte and assembling all-solid-state LiÀ S batteries (ASSLSBs) are good solutions to eliminate the shuttle effect and safety issues, such as (Li, La)TiO 3 , LATP, LAGP, Li garnet [12][13][14][15] , Li 2 S-P 2 S 5 and Li 2 S-SiS 2 solid electrolytes. [16,17] Liang et al used the PEO/LATP (ceramic)/ PEO (4.8 × 10 À 4 S cm À 1 ) as solid electrolyte can achieve an initial discharge capacity of 1035 mAh g À 1 (sulfur utilization 60%) at 0.1 C. [18] Suzuki et al used Li 3.…”

Carbon Foam Fibers with a Concentric Tube‐Core/Three‐Dimensional Nanosheet‐Sheath Structure for High‐Performance Lithium‐Sulfur Batteries

“…For the EIS patterns, it consists of a semicircle and a slopping line, corresponding to charge transfer resistance (R ct ) and diffusion resistance (R s ) in the low and high frequency, respectively [27] . Among them, the value of R s can be obtained from the bulk resistance [28] . For HPCF‐800/S and HPCF‐900/S cathodes, the R s value is 7.23 and 11.93 Ω, respectively.…”