The lithium-sulfur battery is considered one of the most promising candidates for portable energy storage devices due to its low cost and high energy density.However, many critical issues, including polysulfide shuttling, self-discharge, lithium dendritic growth, and thermal hazards need to be addressed before the commercialization of lithium-sulfur batteries. To this end, tremendous efforts have been made to explore battery configurations and components, such as electrodes, electrolytes, and separators, among which the separator plays an especially critical role in addressing aforementioned issues. Thus, this review analyzes the mechanisms and interactions of these critical issues and summarizes both the function of separators and recent progress made towards remedying such issues. Additionally, promising directions for the development of separators in lithium-sulfur batteries are proposed. K E Y W O R D Slithium dendrite, lithium-sulfur batteries, self-discharge, separator, shuttle effect, thermal hazardsThe first two authors contributed equally to this work.
High utilization efficiency of electrode materials is of great importance for achieving excellent electrochemical performance of supercapacitors. In this paper, we report growth of aligned polyaniline (PANI) nanowires on internal surface of macroporous carbon (MC) derived from luffa sponge fibers for increasing their utilization efficiency. The pores in the MC are densely packed, straight, and parallel with the diameter at micrometer scale, which provide easy paths for reaction solution to penetrate and thus enable growth of the PANI nanowires on the internal wall surface. Due to full exposure towards electrolyte the PANI nanowires exhibit high utilization efficiency, leading to high specific capacitance up to 1500 F g -1 (1 A g -1 ). As the macropores allow easy penetration of the electrolyte the PANI nanowires show high rate capability with the capacitance retention up to 70% with increasing the current density from 1 to 10 A g -1 . Symmetric supercapacitors assembled using the MC/PANI materials possess high energy density (19 Wh kg -1 at 0.5 kW kg -1 ) and long cycle life (83% retention after 7000 cycles). Considering the abundance and green production of the luffa sponge the MC/PANI composites are promising for industrial application of supercapacitors.
Electrochemical performance and production cost are the main concerns for the practical application of supercapacitors. Here we report a simple and universally applicable method to prepare hybrid metal oxides by metal redox reaction utilizing the inherent reducibility of metals and oxidbility of for the first time. As an example, Ni(OH)2/MnO2 hybrid nanosheets (NMNSs) are grown for supercapacitor application by self-reaction of Ni foam substrates in KMnO4 solution at room temperature. The obtained hybrid nanosheets exhibit high specific capacitance (2,937 F g−1). The assembled solid-state asymmetric pseudocapacitors possess ultrahigh energy density of 91.13 Wh kg−1 (at the power density of 750 W kg−1) and extraordinary cycling stability with 92.28% capacitance retention after 25,000 cycles. Co(OH)2/MnO2 and Fe2O3/MnO2 hybrid oxides are also synthesized through this metal redox mechanism. This green and low-cost method is capable of large-scale production and one-step preparation of the electrodes, holding promise for practical application of high-performance pseudocapacitors.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.