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The electrochemical properties and performances of lithium-ion batteries are primarily governed by their constituent electrode materials, whose intrinsic thermodynamic and kinetic properties are understood as the determining factor. As a part of complementing the intrinsic material properties, the strategy of nanosizing has been widely applied to electrodes to improve battery performance. It has been revealed that this not only improves the kinetics of the electrode materials but is also capable of regulating their thermodynamic properties, taking advantage of nanoscale phenomena regarding the changes in redox potential, solid-state solubility of the intercalation compounds, and reaction paths. In addition, the nanosizing of materials has recently enabled the discovery of new energy storage mechanisms, through which unexplored classes of electrodes could be introduced. Herein, we review the nanoscale phenomena discovered or exploited in lithium-ion battery chemistry thus far and discuss their potential implications, providing opportunities to further unveil uncharted electrode materials and chemistries. Finally, we discuss the limitations of the nanoscale phenomena presently employed in battery applications and suggest strategies to overcome these limitations.

A highly soluble and multi-redox phenazine-based molecule, BMEPZ, is redesigned through bio-inspiratioin as high-performance catholyte material for NORFBs. A full-flow RFB based on BMEPZ/FL redox couple exhibits cell voltage of 1.2 and 2.0 V and stable cycling. The highest energy density among NORFBs is attained based on the multi-redox capability and high solubility.

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A spatial confinement effect of copper nanoparticles in an ordered mesoporous γ-Al2O3, which is synthesized by an evaporation induced self-assembly (EISA) method, was investigated to verify the enhanced catalytic activity and stability with less aggregation of copper crystallites during direct synthesis of dimethyl ether (DME) from syngas. The surface acidity of the mesoporous Al2O3 and the metallic copper surface area significantly altered catalytic activity and stability. The ordered mesopore structures of Al2O3 were effective to suppress the aggregation of copper nanoparticles even under reductive CO hydrogenation conditions through the spatial confinement effect of the ordered mesopores of Al2O3 as well as the formation of strongly interacted copper nanoparticles with the mesoporous Al2O3 surfaces by partial formation of the interfacial CuAl2O4 species. The aggregation of copper nanoparticles on the bifunctional Cu/meso-Al2O3 having an ordered mesoporous structure was effectively suppressed due to the partial formation of the thermally stable spinel copper aluminate phases, which can further generate new acid sites for dehydration of methanol intermediate to DME.