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The potential of organic electrodes in lithium‐ion batteries (LIBs) is highlighted by their cost‐effectiveness and natural abundance. However, the dissolution of the active material in the electrolyte is a major obstacle to their use in LIBs. Although high‐concentration electrolytes (HCEs) have been proposed to address this issue, they face challenges such as high viscosity, poor wettability, and suboptimal ion conductivity. Hence, this study introduces diluted electrolytes as non‐solvating electrolytes to offset the physical limitations of HCEs and suppress the dissolution of organic electrodes. When a diluted electrolyte is used, perylene‐3,4,9,10‐tetracarboxylic dianhydride (PTCDA)—a notable organic electrode material—demonstrates superior capacity retention and rate performance, achieving 91% of capacity retained at 1000 mA g−1 over 1000 cycles. Through electrochemical and spectroscopic measurements and molecular dynamics simulations, the diluted electrolyte successfully inhibits and demonstrates the dissolution of the active material, preventing capacity loss and the detrimental shuttle effect. This study presents a promising strategy for achieving highly reversible organic electrode‐based LIBs through the development of nonsolvating electrolytes. [ABSTRACT FROM AUTHOR]

All-solid-state batteries (ASSBs) are promising alternatives to lithium-ion batteries owing to their high energy density and safety. Recent studies on "anodeless" electrodes with Li-soluble metallic materials (e.g., silver nanoparticles) and carbon materials in ASSBs have shown improvements in the energy density of these cells. However, poor dispersion between metal nanoparticles and carbon materials in anodeless electrodes leads to disproportionate electrochemical phenomena. Moreover, the dendritic growth and uneven reactions caused by these imbalances impair the life cycle of ASSB cells. To address this issue, we introduce carbon-supported silver nanoparticle-based anodeless electrodes. Ag ion complexes were thermally reduced, and the reduced silver nanoparticles were well dispersed on the carbon surface. This electrode reduces overpotential during the lithiation process with less silver and provides high-rate performance. An ASSB cell using the anodeless electrode with carbon-supported silver nanoparticles exhibits 91% capacity retention after 500 cycles. [ABSTRACT FROM AUTHOR]

Li–O2 batteries attract extensive attention because they exhibit the highest theoretical energy density among the rechargeable batteries reported so far. However, most studies have focused on improving the cyclability and efficiency of Li–O2 batteries under low-capacity conditions instead of under practical conditions. Here, we increase the capacity range of Li–O2 batteries to a practical condition of 5 mA h cm−2 by introducing CF3(CF2)2I as a dual-functional additive. An electrolyte comprising 1 M LiNO3 in N,N-dimethylacetamide and CF3(CF2)2I provides stable cycle retention and high reversibility even at high areal capacity. Ab initio molecular dynamics simulations demonstrate that the reaction between CF3(CF2)2I and Li metal is spontaneous and leads to the simultaneous formation of LiF as a protective layer on Li metal and LiI as a redox mediator for the oxygen evolution reaction. This study provides new insights for the development of electrolyte additives toward practical Li–O2 batteries. [ABSTRACT FROM AUTHOR]

Lithium oxygen batteries (LOBs) are considered promising next‐generation lithium batteries owing to their high theoretical specific energy density. However, several issues must be addressed for realizing the practical applications of LOBs. Among them, the evolution of singlet oxygen (1O2)—which undergoes vigorous reactions that compromise the stability of the system—is a key challenge. The high overpotential induced by low‐conductivity lithium peroxide necessitates the use of a redox mediator (RM) to facilitate the charging process; however, RMs can also be degraded by 1O2, which limits their efficacy in the long term. Recently, it was revealed that certain RMs play a role in suppressing the generation of 1O2. In this review, the relationship between the RM and 1O2 is described. Based on recent understandings, clear insight into RM reactions toward 1O2 and possible future research directions will be provided. [ABSTRACT FROM AUTHOR]

A stable electrolyte is critical for practical application of lithium–oxygen batteries (LOBs). Although the ionic conductivity and electrochemical stability of the electrolytes have been extensively investigated before, their oxygen solubility, viscosity, volatility, and the stability against singlet oxygen (1O2) still need to be comprehensively investigated to provide a full picture of the electrolytes, especially for an open system such as LOBs. Herein, a systematic investigation is reported on the localized high‐concentration electrolytes (LHCEs) using different fluorinated diluents in comparison with those of conventional electrolytes. The physical properties and activation energies for reactions with singlet oxygen (1O2) of these electrolytes are calculated by density functional theory. The electrochemical performances of LOBs using these electrolytes are compared. This study reveals that the correlation between the stability of the electrolytes and their physical and electrochemical properties depends strongly on the diluents in LHCEs. Therefore, it shines light on the rational design of new electrolytes for LOBs. [ABSTRACT FROM AUTHOR]

The goal of limiting global warming to 1.5 °C requires a drastic reduction in CO2 emissions across many sectors of the world economy. Batteries are vital to this endeavor, whether used in electric vehicles, to store renewable electricity, or in aviation. Present lithium-ion technologies are preparing the public for this inevitable change, but their maximum theoretical specific capacity presents a limitation. Their high cost is another concern for commercial viability. Metal-air batteries have the highest theoretical energy density of all possible secondary battery technologies and could yield step changes in energy storage, if their practical difficulties could be overcome. The scope of this review is to provide an objective, comprehensive, and authoritative assessment of the intensive work invested in nonaqueous rechargeable metal-air batteries over the past few years, which identified the key problems and guides directions to solve them. We focus primarily on the challenges and outlook for Li-O2 cells but include Na-O2, K-O2, and Mg-O2 cells for comparison. Our review highlights the interdisciplinary nature of this field that involves a combination of materials chemistry, electrochemistry, computation, microscopy, spectroscopy, and surface science. The mechanisms of O2 reduction and evolution are considered in the light of recent findings, along with developments in positive and negative electrodes, electrolytes, electrocatalysis on surfaces and in solution, and the degradative effect of singlet oxygen, which is typically formed in Li-O2 cells. [ABSTRACT FROM AUTHOR]