Abstract
Low conductivity and shuttle effect of lithium polysulfides (LiPSs) are the major impediments to the development of lithium-sulfurbatteries. Therefore, there is an urgent need for a reasonably designed host to simultaneously meet the needs of sulfur and LiPSs storage and improve the conductivity of the cathode material. In this work, inspired by synergetic effect, we design excellent adsorptive TiO2@yV2O5 (y = 0.025–0.045) bifunctional composites. And the different compositions of matrix material can be fabricated via manipulating the amount of KOH, which combines the advantages of high stability of TiO2 and strong adsorption of V2O5. The V2O5 exists inside TiO2 and part of it is used to provide a cavity, which can buffer volume expansion and store LiPSs and sulfur. The other can enhance the activity and energy of TiO2, thereby go a step further enhance the reaction kinetics. In addition, this TiO2@0.040 V2O5/S electrode exhibits high capacity retention of 91% and 93% at 0.5 C and 1 C after 50 cycles. And the cell exhibits a small polarization (202 mV at 0.1 C, 202 mV at 0.2 C and 234 mV at 0.5 C).
NSTL
Elsevier