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Three dimensionally ordered macroporous (3DOM) carbons with mesoporous walls were prepared by a colloidal crystal templating method. A three dimensionally ordered composite consisting of monodisperse polystyrene (PS) latex (100-450 nm) and colloidal silica (5-50 nm) was prepared by an evaporation process of suspensions containing PS latex and colloidal silica in water. In the course of the heat treatment of this composite membrane at 573 K under an inert atmosphere, the PS was melted and penetrated into the spaces between the colloidal silica. The penetrated PS was carbonized during further heat treatment to provide a very thin carbon layer on the colloidal silica, and the macropore corresponding to the PS particle size was formed simultaneously. After this procedure, the 3DOM carbon with mesoporous walls was obtained by removing the silica particles. From the results of scanning electron microscope observations and nitrogen adsorption-desorption measurements, it was confirmed that the prepared carbon had a bimodal porous structure, and the sizes of macropores and mesopores of prepared carbon were in good agreement with the sizes of the PS and silica particles used as templates, respectively. The bimodal porous carbon, which had a specific surface area of 1500 m 2 g À1 and 5 nm mesopores, showed highest capacitance of 120 F g À1 in propylene carbonate solution containing 1 mol dm À3 (C 2 H 5 ) 4 NBF 4 . The mesopore size rather than macropore size gave significant effects on the rate capability of carbon electrode during charge and discharge. The bimodal porous carbon having 5 nm mesopores showed an excellent rate capability and its capacitance at a high current density of 4 A g À1 was 109 F g À1 .

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Fluoride ion batteries (FIBs) are regarded as promising energy storage devices, and it is important and urgent to develop cathode materials with high energy densities for use in FIBs.

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A star-shaped copolymer, poly͑styrene͒-block-poly͓poly͑ethylene glycol͒ methyl ethyl methacrylate ͑PS-block-PPEGMA 2 ͒ 8 , was synthesized by the combination of living anionic polymerization of styrene and ruthenium-catalyzed living radical polymerization of poly͑ethylene glycol͒ methyl ether methacrylate. The prepared star-shaped copolymer was characterized to evaluate its use as a solid polymer electrolyte ͑SPE͒ in lithium-ion batteries. The star polymer comprised a hard, condensed poly͑styrene͒ part at the center, which enhanced the mechanical properties of the solid-state polymer, and a soft, mobile poly͓poly͑ethylene glycol͒ methyl ethyl methacrylate͔ ͑PPEGMA͒ outer part that was responsible for the high ionic conductivity of the SPE. The design of this star polymer resulted in a well-ordered spherical microphase separation structure, in which the individual star polymers were systematically ordered to form the PPEGMA continuous phase distinctly observed in transmission electron microscopy and atomic force microscopy images. The SPE containing the lithium bis͑pentafluoroethanesulfonyl͒ imide salt exhibited high ionic conductivities due to the unique morphology of the polymer; the ionic conductivity of this salt was 10 −4 S cm −1 at 30°C and 10 −5 S cm −1 at 5°C at ͓Li͔/͓EO͔ = 0.03.Lithium-ion rechargeable batteries are energy-storage devices that have several advantages over conventional secondary batteries such as nickel-cadmium ͑Ni-Cd͒ batteries and nickel-metalhydrides ͑Ni-MH͒ batteries. The advantages of lithium-ion rechargeable batteries are their high electrical performance for a long life cycle, high energy density, low weight, and high operational voltage; further, these batteries do not exhibit memory effects. These features have caused an increase in the popularity of the use of lithium-ion batteries as standard power sources in portable devices such as mobile phones and laptop computers. The application of these batteries has further extended to large-scale equipment such as electrical-power storage systems and in-car systems. In such systems the safety of the device is one of the most important criteria to be satisfied before selecting the batteries. However, most commercially available cells contain liquid or liquid-based electrolytes that are made of flammable organic solvents; thus, these cells posses certain risks such as leakage and spontaneous combustion of the electrolyte. Therefore, there is a need to develop efficient polymer electrolytes that do not have any liquids, i.e., solid polymer electrolytes ͑SPEs͒.Poly͑ethylene oxide͒ ͑PEO͒ coupled with a lithium salt is a typical example of an ion conductive material, and its potential use as an SPE has been studied extensively. 1-25 However, the ionic conductivity of the electrolyte of this material ͑approximately 10 −7 S cm −1 ͒ at room temperature was not sufficient for its practical use in batteries. It is desirable for SPEs to exhibit liquidlike ionic conductivity and mechanical properties that are capable of separating the electrode. Alt...

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With the increasing development of electric vehicles and portable devices, there is a strong requirement for high-energy batteries. To improve battery energy, multielectron transfer electrode reactions can be applied. Previously, batteries based on fluoride-ion shuttle (F– ion shuttle batteries, FiBs) have been reported, utilizing electrodes with multielectron transfer reactions. Although these FiBs exhibit high theoretical energy densities, reported capacities are significantly less than theoretical values. Moreover, charge–discharge mechanisms are not clarified. In this study, the feasibility of FiBs as extremely high-energy batteries has been demonstrated using a model cell with a Cu cathode and a LaF3 anode. By conducting experiments under an atmosphere without impurities, the Cu/LaF3 battery has been successfully operated with almost theoretical capacity. The Cu/LaF3 battery has been exhibited a superior cycle life at 80 °C, with feasibility for room-temperature operation.