Abstract：In order to improve the adsorption capability of carbon materials toward polysulfides, a porous conductive material was prepared by in-situ deposition of MnO2 on surfaces of activated carbon fiber in its felt (ACFF), named MnO2@ACFF. The MnO2@ACFF was placed between separator and sulfur electrode as an interlayer. The existence of MnO2@ACFF interlayer effectively controlled polysulfide shuttle when using heavy S-loaded electrode, thereby promoting utilization of active substance and coulombic efficiency, improving the electrode cyclability ascribed to the decrease in electrode polarization and electrochemical impedance, preventing the electrode from sudden failure. The sulfur electrode with an S-loading of 15mg/cm2, delivered a discharge capacity of 430 mA·h/g after 350 evaluation cycles at a current density of 2 mA/cm2. Though increase in S-loading led to the deterioration of sulfur electrode, the sulfur electrodes with S-loading of 20 mg/cm2 and 30 mg/cm2 presented the discharge capacities of 736 mA·h/g and 446 mA·h/g after 100 cycles at 0.1 C, respectively, meanwhile the retention rate of specific capacity reached 65%, the areal specific capacity and energy density kept 64% and 42%, higher than those of lithium-ion batteries.
FLORES Jose,LI Zhoupeng. Effect of an Interlayer Derived from MnO2 Modification of Activated Carbon Fiber Felt on Cycle Stability of Sulfur Electrode with High Sulfur Loadings[J]. Chemical Reaction Engineering and Technology, 2023, 39(3): 219-226.
