Wide Working Temperature Range Rechargeable Lithium–Sulfur Batteries: A Critical Review

At the technological forefront of energy storage, there is still a continuous upsurge in demand for high energy and power density batteries that can operate at a wide range of temperature. Rechargeable lithium sulfur batteries stand out among other advanced cell concepts owing to their ultrahigh theoretical gravimetric energy density characteristic as well as merits of low cost and environmental friendliness. Although achieving good operability of ambient lithium sulfur batteries, extending their workability to both higher and lower temperatures is also of paramount importance especially for future task-specific applications. As a first attempt, this review presents a comprehensive understanding on the advances, challenges, and future research directions on lithium sulfur batteries operating at both low and high temperature extremes. From a material perspective, the workability of sulfur-containing cathode materials, advanced electrolytes (from conventional liquid to quasi- and all-solid-state electrolytes), lithium metal anodes and the electrochemically inert components (separators and interlayer materials) at extreme temperatures are thoroughly analyzed. The insurmountable challenges and mechanistic understandings caused by thermal changes are critically reviewed. Finally, potential future research directions and prospects for lithium sulfur batteries operated at a wide range of temperature are also proposed.     

In Situ Reconstruction of Electrocatalysts for Lithium–Sulfur Batteries: Progress and Prospects

The current research of Li–S batteries primarily focuses on increasing the catalytic activity of electrocatalysts to inhibit the polysulfide shuttling and enhance the redox kinetics. However, the stability of electrocatalysts is largely neglected, given the premise that they are stable over extended cycles. Notably, the reconstruction of electrocatalysts during the electrochemical reaction process has recently been proposed. Such in situ reconstruction process inevitably leads to varied electrocatalytic behaviors, such as catalytic sites, selectivity, activity, and amounts of catalytic sites. Therefore, a crucial prerequisite for the design of highly effective electrocatalysts for Li–S batteries is an in-depth understanding of the variation of active sites and the influence factors for the in situ reconstruction behaviors, which has not achieved a fundamental understanding and summary. This review comprehensively summarizes the recent advances in understanding the reconstruction behaviors of different electrocatalysts for Li–S batteries during the electrochemical reaction process, mainly including metal nitrides, metal oxides, metal selenides, metal fluorides, metals/alloys, and metal sulfides. Moreover, the unexplored issues and major challenges of understanding the reconstruction chemistry are summarized and prospected. Based on this review, new perspectives are offered into the reconstruction and true active sites of electrocatalysts for Li–S batteries.     

Combined Defect and Heterojunction Engineering in ZnTe/CoTe2@NC Sulfur Hosts Toward Robust Lithium–Sulfur Batteries

Lithium–sulfur batteries (LSBs) are feasible candidates for the next generation of energy storage devices, but the shuttle effect of lithium polysulfides (LiPSs) and the poor electrical conductivity of sulfur and lithium sulfides limit their application. Herein, a sulfur host based on nitrogen-doped carbon (NC) coated with small amount of a transition metal telluride (TMT) catalyst is proposed to overcome these limitations. The properties of the sulfur redox catalyst are tuned by adjusting the anion vacancy concentration and engineering a ZnTe/CoTe₂ heterostructures. Theoretical calculations and experimental data demonstrate that tellurium vacancies enhance the adsorption of LiPSs, while the formed TMT/TMT and TMT/C heterostructures as well as the overall architecture of the composite simultaneously provide high Li⁺ diffusion and fast electron transport. As a result, v-ZnTe/CoTe₂@NC/S sulfur cathodes show excellent initial capacities up to 1608 mA h g⁻¹ at 0.1C and stable cycling with an average capacity decay rate of 0.022% per cycle at 1C during 500 cycles. Even at a high sulfur loading of 5.4 mg cm^–2, a high capacity of 1273 mA h g⁻¹ at 0.1C is retained, and when reducing the electrolyte to 7.5 µL mg⁻¹, v-ZnTe/CoTe₂@NC/S still maintains a capacity of 890.8 mA h g⁻¹ after 100 cycles at 0.1C.     

Description of the Magnetization Oscillations of a Silicon Nanostructure in Weak Fields at Room Temperature. The Lifshitz–Kosevich Formula with Variable Effective Carrier Mass

Semiconductors - A formalism of the statistical approach to describing de Haas–van Alphen oscillations known as the Lifshitz–Kosevich formula is developed as applied to a...