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Lithium-ion batteries (LIBs) experience implausible lithium plating, a deterioration in service life, and a decrease in rate performance at different lithium-ion battery operating conditions, regardless of their substantial advancements in energy conservation. Lithium plating on the anode electrode surface escalates its performance deterioration and creates safety risks for LIBs. The main cause of these issues is the limitations in electrochemical kinetics at the electrode and electrolyte interface. In this study, we emphasize the use of a voltage relaxation profile analysis to identify the onset of lithium plating during progressive cycling at various states of charge (SOC) and discharge rates. In addition, we report the utilization of Al2O3 and TiO2 coatings with different weight percentages on graphite as the new anode electrode materials for LIBs. Anode electrodes with small percentages of Al2O3 and TiO2 coatings (0.5 wt.%) on graphite did not exhibit any lithium plating even at 90% SOC at a 4 C discharge rate. This material's ability to inhibit lithium plating has thus been shown to be better than that of a graphite anode electrode alone. High-rate capability and cycle life are also obtained using these anode electrode materials for full cell system. We further demonstrate that differential open-circuit voltage (dOCV) analysis is capable of detecting the onset of Li plating while cycling, suggesting the economic viability of this approach for active Li detection. [ABSTRACT FROM AUTHOR]

Current lithium‐ion batteries have a low theoretical capacity that is insufficient for use in emerging electric vehicles and energy‐storage systems. The development of lithium‐sulfur batteries utilizing Li2S cathodes would be a promising option to overcome the capacity limitation. In this work, new three‐dimensional (3D) honeycomb‐like N‐doped carbon nanowebs (HCNs) have been synthesized through a facile aqueous solution route for use as a cathode material in lithium‐sulfur batteries. The Li2S@HCNs cathode delivers a high discharge capacity of approximately 815 mAh g−1 after 65 cycles at 0.1 C, along with a superior rate capacity of approximately 568 mAh g−1 even at 2 C. The outstanding electrochemical rate performance is ascribed to their unique 3D honeycomb‐like nanoweb structure, consisting of nanowires derived from polypyrrole. These properties greatly enhance the electrochemical reaction kinetics by providing efficient electron pathways and hollow channels for electrolyte transport. Nitrogen doping in the carbon nanowebs also considerably improves the chemisorption properties by tuning affinity between sulfur and oxygen functional groups on the carbon framework. The simple synthesis strategy and the resulting unique electrode structure could present a new avenue in nanostructure research for high‐performance lithium‐sulfur batteries. Electrifying nanowebs: Three‐dimensionally interconnected carbon‐nanowire composites are demonstrated as electrode for use in the lithium‐sulfur battery, and the electrochemical properties are investigated with Li2S. These electrodes can provide efficient pathways for charge transport and promote diffusion of the liquid electrolyte for the enhanced electrochemical reaction kinetics. [ABSTRACT FROM AUTHOR]

Current lithium-ion batteries have a low theoretical capacity that is insufficient for use in emerging electric vehicles and energy-storage systems. The development of lithium-sulfur batteries utilizing Li 2 S cathodes would be a promising option to overcome the capacity limitation. In this work, new three-dimensional (3D) honeycomb-like N-doped carbon nanowebs (HCNs) have been synthesized through a facile aqueous solution route for use as a cathode material in lithium-sulfur batteries. The Li 2 S@HCNs cathode delivers a high discharge capacity of approximately 815 mAh g -1 after 65 cycles at 0.1 C, along with a superior rate capacity of approximately 568 mAh g -1 even at 2 C. The outstanding electrochemical rate performance is ascribed to their unique 3D honeycomb-like nanoweb structure, consisting of nanowires derived from polypyrrole. These properties greatly enhance the electrochemical reaction kinetics by providing efficient electron pathways and hollow channels for electrolyte transport. Nitrogen doping in the carbon nanowebs also considerably improves the chemisorption properties by tuning affinity between sulfur and oxygen functional groups on the carbon framework. The simple synthesis strategy and the resulting unique electrode structure could present a new avenue in nanostructure research for high-performance lithium-sulfur batteries., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)