Inhibiting the shuttle effect of soluble polysulfides and improving slow reaction kinetics are key factors for the future development of Li–S batteries. Herein, edelweiss shaped NiCo2O4 hollow nanospheres with a high surface area were prepared by a simple template method to modify the separator to realize multiple physical constraints and strong chemical anchoring on the polysulfides. On one hand, the good electrolyte wettability of NiCo2O4 promoted the migration of Li-ions and greatly improved the dynamics. On the other hand, mesoporous NiCo2O4 nanomaterials provided many strong chemical binding sites for loading sulfur species. The hollow structure also provided a physical barrier to mitigate the sulfur species diffusion. Therefore, the modified separator realized multiple physical constraints and strong chemical anchoring on sulfur species. As a result, the sulfur cathode based on this composite separator showed significantly enhanced electrochemical performance. Even at 4 C, a high capacity of 505 mAh g−1 was obtained, and about 80.6% could be retained after 300 cycles.

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With precision agriculture developing rapidly worldwide, water-saving, energy-saving, environment-friendly, and efficient agricultural production activities are effective ways to address human needs for agricultural products under the conditions of intensifying climate change, limited available arable land resources, and rapid population growth. Ground-based plant-protection machinery applied to large fields has difficulty solving the pest and disease prevention needs of mountain orchards since they feature undulating topography changes and low standardization of orchards. Unmanned aerial vehicles (UAVs) have broad development prospects in pest control in mountain orchards because of their advantages of not being restricted by terrain, strong maneuverability, and hover ability. This paper reviews the recent development of plant-protection UAVs from three perspectives, i.e., positioning and navigation technology, flight attitude control technology, and route planning in mountain orchards. We highlight that the future research should focus on following technology development, including (1) positioning navigation technology with high positioning accuracy and strong anti-interference capability, (2) intelligent control technology with high dynamic stability and better calculation accuracy, and (3) the optimization of the route-planning algorithm covering multiple constraints and the cluster cooperative operation scheme of plant-protection UAVs applicable to mountain orchards. These reviewed results could provide a reference for the future development of plant-protection UAVs, which will become the focus of future research.