Bio‐Waste Derived Carbon as Interlayer and Scaffold for Li‐S Batteries

Abstract

In an attempt to explore bio‐waste derived carbon for sulfur cathode and to exploit it further as an interlayer along with an interest to understand the individual and synergistic effect of bio‐carbon, jamun seed derived porous carbon (bio‐carbon) is deployed. Bio‐carbon contains micro‐pores and bestowed with high specific surface area of 2029 m2/g and pore volume of 1.2 ccm/g. Specifically, 60 wt.% S@bio‐carbon cathode with bio‐carbon interlayer exhibits 642 mAh/g at C/2 rate up to 75 cycles, which is two times higher than the capacity obtained without bio‐carbon interlayer. Notably, bio‐carbon interlayer leads to a 2–3 fold decrease in shuttle current and improves the performance of Li−S cell. Besides, effect of combination of bio‐carbon and Super‐P carbon as scaffold and/or as interlayer is studied, wherein bio‐carbon as scaffold and as interlayer outperforms in terms of capacity retention, better Coulombic efficiency and higher active material holding capability in Li−S batteries. Furthermore, even at a high rate of 3C, bio‐carbon/S‐60 cathode with bio‐carbon interlayer exhibits a capacity of 256 mAh/g, mainly due to the facile lithium kinetics of sulfur in the jamun seed derived bio‐carbon interlayer containing Li−S batteries.

Repurposing Waste Tires as Tunable Frameworks for Use in Sodium-Ion and Lithium–Sulfur Batteries

“…With such strong emphasis on the impact of the carbon framework and impurities in efficient and successful Na half-cell function, it is hence unsurprising that the design of carbon materials for alternative systems such as lithium–sulfur (Li–S) would draw inspiration from these works, despite dealing with a completely different redox mechanism. Most research on the carbon component of the Li–S cell electrode has focused primarily on the carbon morphology, ,,,,,− much like in the case of Na-ion and Li-ion cells. This is not unreasonable considering the primary role of carbon in a Li–S cell electrode is as a conductive framework.…”

“…In addition to Na half-cell technologies, there is also profitability of waste-derived carbons to be used as electrode components for lithium–sulfur (Li–S) cells. − While the capacity source of Li–S cells is reliant on sulfur-containing materials rather than carbon, the incorporation of a carbon framework as a component in the electrode is often necessary for the Li–S cell to be sufficiently conductive for current to pass through due to the insulating nature of sulfur. Reports focusing on the design of these carbon frameworks for Li–S cell electrodes also typically focus on the functionality of these materials as a means to physically confine redox-active sulfur species, thus mitigating the loss of active material from shuttling in the electrolyte. − …”