N-doped vanadium pentoxide materials for inhibiting shuttle effect in lithium-sulfur batteries

Lithium-sulfur batteries have high energy density and are one of the most promising secondary batteries to alleviating energy scarcity, but many aspects limit their practical applications. Among them, the shuttle effect produced when soluble polysulfides pass through the separator is a big reason for the slow progress in commercialization. In this study, N-doped vanadium pentoxide materials (SZV) were designed and synthesized as a functional material for separator. The SZV material provides abundant adsorption sites and catalytic sites and can effectively inhibit the shuttle effect of polysulfides. The first cycle discharge capacity was 982 mAh g−1 at 1 C, and the capacity decay was only 0.056% per cycle after 1400 cycles. The SZV separator battery have an initial capacity of 869 mAh g−1 at 4 C and retain a capacity of 648 mAh g−1 after 200 cycles. Notably, the modified separator batteries can adapt to temperature changes and show excellent cycling performance. The SZV separator battery has a capacity of 700 mAh g−1 at 60 °C and 864 mAh g−1 at 10 °C after 100 cycles at 0.5 C.