Lithium-ion batteries (LIBs) have been widely used for portable electronics and electric vehicles; however, the low capacity in the graphite anode limits the improvement of energy density. Transition-metal selenides are promising anode material candidates due to their high theoretical capacity and controllable structure. In this study, we successfully synthesize a bimetallic transition-metal selenide nanocube composite, which is well embedded in a nitrogen-doped carbon matrix (denoted as CoNiSe2/NC). This material shows a high capacity and excellent cycling for Li-ion storage. Specifically, the reversible capacity approaches ∼1245 mA h g–1 at 0.1 A g–1. When cycled at 1 A g–1, the capacity still remains at 642.9 mA h g–1 even after 1000 cycles. In-operando XRD tests have been carried out to investigate the lithium storage mechanism. We discover that the outstanding performance is due to the unique CoNiSe2/NC nanocomposite characteristics, such as the synergistic effect of bimetallic selenide on lithium storage, the small particle size, and the stable and conductive carbon structure. Therefore, this morphology structure not only reduces the volume change of metal selenides but also produces more lithium storage active sites and shortens lithium diffusion paths, which results in high capacity, good rate, and long cycling.

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The safety issue represents a long‐standing obstacle that retards large‐scale applications of high‐energy lithium batteries. Among different causes, thermal runaway is the most prominent one. To date, various approaches have been proposed to inhibit thermal runaway; however, they suffer from some intrinsic drawbacks, either being irreversible (one‐time protection), using volatile and flammable electrolytes, or delayed thermal protection (140–150 °C). Herein, this work exploits a non‐volatile, non‐flammable, and thermo‐reversible polymer/ionic liquid gel electrolyte as a built‐in safety switch, which provides highly precise and reversible thermal protection for lithium batteries. At high temperature, the gel electrolyte experiences phase separation and deposits polymer on the electrode surfaces/separators, which blocks Li+ insertion reactions and thus prevents thermal runaway. When the temperature decreases, the gel electrolyte restores its original properties and battery performance resumes. Notably, the optimal protection effect is achieved at 110 °C, which is the critical temperature right before thermal runaway. More importantly, such a thermal‐protection process can repeat multiple times without compromising the battery performance, indicating extraordinary thermal reversibility. To the authors' knowledge, such a precise and reversible protection effect has never been reported in any electrolyte systems, and this work opens an exciting avenue for safe operation of high‐energy Li batteries.

Aims: Production of chili (Capsicum annuum Linnaeus; Solanaceae) in rain-fed regions of Nepal during the winter is constrained by the limited availability of soil moisture. Mulching has been a proven tool to conserve soil moisture and enhance yield. A field study was conducted in the winter of 2019 to identify the most suitable mulch that enhances the yield and yield attributing parameters of chili. Study Design: Seven treatments with three replications were evaluated under the randomized complete block design. Among the treatments, rice straw (5 kg/plot) and water reed (5 kg/plot) were used as natural mulches. While, plastic mulches: transparent (25 µ), silver (25 µ), black (25 µ), and black thick (50 µ) (double thickness) were used as synthetic mulches. Only soil with no mulch was the control. Place and Duration of Study: The study was conducted at Bangau, Dang, Nepal from November 2019 to May 2020. Methodology: We measured soil temperature at 10 cm depth using soil thermometer, and calculated soil moisture through oven dry method. Similarly, weight of ten fresh and ten dry fruits was recorded from each plot using an electronic scale. Number of fruits per plant was also counted. All the data were analyzed using ANOVA and means were separated following a post hoc test. Results: The highest soil moisture (18.38%), number of fruits per plant (24.91), fruit fresh weight per ten fruits (59.86 g), and fruit dry weight per ten fruits (14.65 g) were recorded in black thick plastic mulched plots. Furthermore, the lowest fresh weed weight (95.30 g) was also measured in black thick plastic mulched plots. Whereas, the highest soil temperature (18.92°C) was recorded in transparent plastic mulched plots. Conclusion: This study concludes black thick plastic as the most effective among the treatments tested in this study in enhancing yield and yield attributing parameters of chili.