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To address low electrical conductivity of sulfur and “poly‐sulfide shuttle” for constructing sulfur hosts with excellent cyclic stability, CoSnO3/CNTs composites are successfully synthesized by combining CoSnO3 cubes and carbon nanotubes (CNTs) via coprecipitation and annealing process. CoSnO3 cubes are bound by continuous carbon nanotube networks, with high specific surface area and vast mesoporous. CoSnO3 with multiple polar active sites has a strong chemical adsorption effect on lithium polysulfide, suppressing the shuttle effect. The carbon nanotubes have continuous conductive networks, which can provide physical confinement with polysulfides and good electrical conductivity. Through the effective combination of advantages of CoSnO3 and carbon nanotubes, CoSnO3/CNTs/S exhibits excellent sulfur storage performance. The maximum discharge capacity of CoSnO3/CNTs/S is 453.3 mAh g−1 at a current density of 0.2 C. After 500 cycles, the discharge specific capacity is still 377.7 mAh g−1. The simple synthesis of CoSnO3/CNTs/S with long cycle life provides a new direction for the future LSBs cathode material research.

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To solve the problem of low conductivity of sulfur and "shuttle effect" of lithium polysulfides, CoSnO 3 nanocubes wrapped by carbon nanofibers (CoSnO 3 @CNFs) are synthesized by coprecipitation, electrospinning and calcination techniques. CoS-nO 3 provides plentiful polar active sites, which restrains the dissolution of polysulfides with chemical interaction. Carbon nanofibers not only provide more ion transport channels, but also increase physical adsorption, provide active sites, and improve the conductivity of the electrode material. As a result, CoSnO 3 @CNFs can carry about 60 % sulfur as guest. Evaluated as cathode material for lithium-sulfur batteries, CoSnO 3 @CNFs/ S displayed an initial discharge capacity of 554.9 mA h g À 1 at 0.2 C, and retained 300.0 mA h g À 1 after 200 cycles. The simple synthesis method, high sulfur loading capacity and long cycle life make CoSnO 3 @CNFs extremely attractive for practical applications.