A Separator Modified with Rutile Titania and Three-Dimensional Interconnected Graphene-Like Carbon for Advanced Li-S Batteries

As an advanced energy-storage system, Li-S batteries have attracted much attention, but there is still a series of problems hindering their commercialization, such as the 'shuttle effect' and corrosion of lithium anodes. To alleviate these two important problems simultaneously, we modified the separators with spherical rutile TiO2 with oxygen vacancies (abbreviated OT) and three-dimensional interconnected graphene-like carbon (abbreviated GC) for advanced Li-S batteries to improve the electrochemical performance. The modified separators (abbreviation OTCD) have low charge transfer impedance, a catalytic effect on polysulfides, and a barrier effect on polysulfides, which can suppress the 'shuttle effect' and prevents the corrosion of lithium anodes in Li-S batteries. The as-prepared Li-S batteries show good cycling stability for 250 cycles with 0.048 % capacity decay per cycle at 1 C. Moreover, the SEM images of lithium anodes after 50 cycles showed that the lithium anodes were uncorroded. This work provides a practical and effective reference for the advanced Li-S batteries.

Automated summary

By modifying the separators with spherical rutile TiO2 and three-dimensional interconnected graphene-like carbon, the electrochemical performance of Li-S batteries can be improved by alleviating the 'shuttle effect' and corrosion of lithium anodes.