A high cycling stability of dual‐ion batteries is greatly challenging, as the size required for inserting anions matches only insufficiently with the interlayer spacing of graphite which is often used as positive electrode. Herein, an activated expanded graphite (AEG) electrode is successfully prepared via KOH treatment. The loose structure of AEG accommodates the volume expansion caused by anion intercalation, and the large specific surface area facilitates the immersion of electrolyte ions to afford more energy density. Thus, the cycling stability is largely enhanced without losing capacity. Matching with activated carbon as negative electrode and an ionic liquid electrolyte, the assembled dual‐ion battery achieves an energy density of 43 Wh kg−1 at the power density of 756 W kg−1 within a working window of 0–3.6 V. Specifically, the energy density retains 83 % after 50 cycles. Such effective and low‐cost electrode optimization opens up a new route toward full enhancement on the cycling performance of positive electrodes for dual‐ion batteries.

Dual‐ion batteries are promising devices, owing to their compatibility of high energy density and high power density, provide that the volume expansion of positive graphite and the decomposition of the electrolyte are well addressed. Herein, we report a facile strategy of using low‐cost carbon fiber paper for package enhancement of dual‐ion batteries. The three‐dimensional structure offers both conductivity and structure integrity, while the highly graphitic fiber paper endows the high intercalation potential towards high energy density. High stability results from such integrative electrode structure. Matching with electrical double‐layer capacitive graphene and ionic liquids, with a wide electrochemical stability window, a dual‐ion battery has been fabricated to achieve a specific energy of 149 Wh/kg at a specific power of 1011 W/kg, and the specific energy retains 85 % after 1000 cycles. This accessible 3D paper electrode provides a new route for an integral electrode construct that can be used in ultrastable, high‐efficiency energy‐storage devices.

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In this study, an experiment platform was built up to determine the key parameter, mass transfer coefficient, of the ventilation and dehumidification process in main cable of suspension bridge. On the basis of experimental studies, an empirical formula of the mass transfer coefficient was obtained, which can greatly contribute to control the content of moisture in the main cable of suspension bridges.

The aim of the paper is to analyze the effect of the additives on thermal conductivity of the phase change material. The experiment about heat storage and heat release performance of the composite phase change material which uses sodium acetate trihydrate as host material is studied. The effect of the expanded graphite on the composite phase change material is investigated. The results show that: expanded graphite which can be dispersed evenly in the composite phase change material, the thermal stability is well, significantly improve the thermal conductivity of the composite phase change material.