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High energy density Li−S battery has attracted wide attention because of its promising application in long driving‐range electric vehicles. However, the shuttle effect of polysulfides, electrical insulation and volume‐change of sulfur, remain great challenges. Herein, inspired from a natural mimosa pudica structure, we present a novel nanocomposite which consists of a mimosa pudica‐structured carbon matrix coating with sulfur. The biomimetic configuration is able to structurally‐respond to the volume‐change of sulfur during charge/discharge; and the carbon matrix provides a good conductivity for rapid electron transfer. The carbon/sulfur composite‐based Li−S batteries exhibit a good electrochemical performance including a stable capacity after 1000 cycles, along with a Coulombic efficiency as high as 99.6 %, and an excellent rate‐performance even after three rounds of measurements. In addition, the density function theory modeling is investigated, which confirms the adsorption effect of carbon towards the polysulfides including Li2S4, Li2S6, and Li2S8, enabling a long‐term cycling stability. [ABSTRACT FROM AUTHOR]

Lithium-sulfur battery cathodes still remain a challenge on capacity decay due to the shuttle effect even though a series of strategies have been tried. Here we report a novel matryoshka-like CuS@void@Co 3 O 4 architecture of double micro-cubes (μ -cubes) that locks sulfur between the CuS core and the Co 3 O 4 shell. Plenty of existing spaces between the μ -cubes suffice a high loading of sulfur and volumetric accommodation. The robust, double closed cubes configuration greatly enhances the confinement of polysulfides. In parallel, the CuS core increases the electronic conductivity and contributes to additional capacity, while the Co 3 O 4 shell ensures a better interface activity. A high Li+ ion diffusion coefficient is obtained during the sulfur and lithium sulfide transformation. The constructed battery displays an initial capacity up to 1480 mAh g−1, and a Coulombic efficiency (CE) exceeding 99%. A capacity retention higher than 500 mAh g−1 with a CE larger than 99.8% after cycling 400 times at 0.2 C are achieved. In addition, under a temperature of −5 °C, a high capacity of 700 mAh g−1 at 0.2 C after 200 cycles is achieved, indicating a good low-temperature tolerance. [ABSTRACT FROM AUTHOR]