Inhibition on polysulfides dissolve during the discharge-charge by using fish-scale-based porous carbon for lithium-sulfur battery

The fish scale derived hierarchical porous carbon has been studied as an inhibitor to capture the polysulfides for lithium-sulfur battery by ex situ ultraviolet-visible absorption spectroscopy and SEM analysis. The results showed that the capacity retention of the cathode with porous carbon as additive increased from 44% to 59% after 50 cycles at 0.1 C compared with the common cathode. Attracted on the excellent performance of cathode with porous carbon, the asymmetry electrode was fabricated by coating a porous layer on the cathode to trap the polysulfides produced during the discharge-charge process further. The initial discharge specific capacity is 1426 mAhg−1 with a capacity retention of 81% after 50 cycles at 1 C, and retains a reversible capacity of 990 mAhg−1 after 100 cycles with coulombic efficiency above 98%.