Fast charging is considered to be a key requirement for widespread economic success of electric vehicles. Current lithium‐ion batteries (LIBs) offer high energy density enabling sufficient driving range, but take considerably longer to recharge than traditional vehicles. Multiple properties of the applied anode, cathode, and electrolyte materials influence the fast‐charging ability of a battery cell. In this review, the physicochemical basics of different material combinations are considered in detail, identifying the transport of lithium inside the electrodes as the crucial rate‐limiting steps for fast‐charging. Lithium diffusion within the active materials inherently slows down the charging process and causes high overpotentials. In addition, concentration polarization by slow lithium‐ion transport within the electrolyte phase in the porous electrodes also limits the charging rate. Both kinetic effects are responsible for lithium plating observed on graphite anodes. Conclusions drawn from potential and concentration profiles within LIB cells are complemented by extensive literature surveys on anode, cathode, and electrolyte materials—including solid‐state batteries. The advantages and disadvantages of typical LIB materials are analyzed, resulting in suggestions for optimum properties on the material and electrode level for fast‐charging applications. Finally, limitations on the cell level are discussed briefly as well.

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This study reports on the use of tetrabutylammonium dihydrogen trifluoride (TBAH 2 F 3 ) ionic liquid-based electrolytes in the aluminum (Al)−air battery system. The conductivity and activation energy of the electrolytes are reported alongside with electrochemical measurements and Al surface characterizations. The activation process of the Al surface is demonstrated and monitored in the ionic liquid-based electrolyte. The successful activation of the Al surface is obtained via the action of the H 2 F 3 − species present in the ionic liquid. The active species in the electrolyte are analyzed with the use of an attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy method, applied prior and subsequent to cell discharge. Primary Al−air cell evaluations with the use of different anodic discharge current loads, as well as different volume fractions of propylene carbonate (PC), were conducted. Using the electrochemical impedance spectroscopy (EIS) technique, we were able to monitor the wetting process of the air cathode. The use of TBAH 2 F 3 -based electrolytes resulted in high cell capacities (over 70% of the theoretical value). The results achieved and reported in this study are promising and present an additional option for an ionic liquid-based electrolyte for Al−air batteries.

A straightforward, benign, scalable and low-cost molten-state synthesis of nickel phosphides with tunable phase composition, applied both as electrocatalysts for hydrogen evolution reaction and as anode materials for Li-ion batteries.

The fabrication of sulfur-containing carbonaceous anode materials (CS) that show exceptional activity as anode material in Na-ions batteries is reported. To do so, a general and straightforward bottom-up synthesis of CS materials with precise control over the sulfur content and functionality is introduced. The new synthetic path combined with a detailed structural analysis and electrochemical studies provide correlations between i) the sulfur content and chemical species and ii) the structural, electronic, and electrochemical performance of the associated materials. As a result, the new CS substances demonstrate excellent activity as Na-ion battery anode materials, reaching capacity values above 500 mAh g −1 at a current density of 0.1 A g −1 , as well as high reversible sodium storage capabilities and excellent cycling durability. The results reveal the underlying working principles of carbonaceous materials, alongside the storage mechanism of the Na + ions in these advanced sodium-ion battery anode materials and provide a new avenue for their practical realization.

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