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Ferric chloride-graphite intercalation compounds (FeCl3 -GICs) with stage 1 and stage 2 structures were synthesized by reacting FeCl3 and expanded graphite (EG) in air in a stainless-steel autoclave. As rechargeable Li-ion batteries, these FeCl3 -GICs exhibit high capacity, excellent cycling stability, and superior rate capability, which could be attributed to their unique intercalation features. This work may enable new possibilities for the fabrication of Li-ion batteries., (Copyright © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Dual‐ion batteries have shown promising prospect in energy storage, owing to their low material costs, high power capability, and environmental friendliness. However, graphite as the cathode always suffers from structural damage and electrode/electrolyte interface instability, which greatly deteriorate their electrochemical performance. Here, tris(trimethyl‐silyl) phosphite (TMSP) is added as an electrolyte additive to improve the electrochemical performance. TMSP not only scavenges the deleterious species generated by electrolytes, but also produces a thin and uniform cathode–electrolyte interphase layer on graphite. Hence, the electrochemical performance is greatly promoted. In graphite||graphite, the capacity retention is ≈96.8% at 30 °C or 92.5% after 3000 cycles in the presence of TMSP, much better than those without TMSP (62% at 30 °C or 27% after 200 cycles). [ABSTRACT FROM AUTHOR]

Abstract: Honeycomb-like graphitic macroporous carbon (HGMC) was synthesized by means of pyrolysis of NH4HCO3 using Mg powder as reductant in an autoclave at 550°C. The characterization of structure and morphology was carried out by X-ray diffraction (XRD), Raman spectrum, field-emission scanning electron microscopy (FESEM), and (High-resolution) transmission electron microscope [(HR)TEM]. The results of nitrogen adsorption–desorption indicate that the products are macropore materials with the pore size of 1–3μm, and the Brunauer–Emett–Teller (BET) surface area was 14m2/g. As a typical morphology, the possible growth process of HGMC was also investigated and discussed. The experimental results show that the in situ formed MgO microparticles play a template role during the HGMC formation. [Copyright &y& Elsevier]

Abstract: Carbon fibrils with length of 2–3μm formed by stacking graphite sheets of ∼10–40nm in thickness along the 〈001〉 direction were prepared by pyrolysis of tetrahydrofuran at 600°C in the existence of metallic nickel. The spacing of adjacent sheets concentrated on ∼3.8nm and ∼50nm. Metallic nickel played a catalytic role in the formation of carbon fibrils, and a possible formation process was proposed. [Copyright &y& Elsevier]

Graphite, as a typical carbon allotrope, is demonstrated as an available intercalation-type anode material for potassium-ion batteries (PIBs). The main challenges associated with graphite anodes are structural pulverization and instability of the solid electrolyte interphase (SEI) resulting from the repeated volume change during charge/discharge. In this work, a layer of interweaved carbon nanotubes (CNTs) are grown on the surface of micro-size graphite flakes through controllable in-situ catalytic chemical vapor deposition method (CCVD), and the CNTs content can be easily adjusted by varying the deposition time. The CNTs-interweaved layer can not only stabilize the graphite structure but also enhance the diffusion kinetics of K+ during cycling. Furthermore, CNTs also provide a certain amount of capacity. The composite material of in situ growing carbon nanotubes and modified graphite flakes (CNTs-MG) exhibit a reversible capacity of 234 mAh g−1 at 2 A g−1 after 1500 cycles, which is obviously better than that of counterpart graphite flakes. Besides, the K storage mechanism and the effect of the contents of CNTs are also investigated systemically by in-situ Raman spectra and electrochemical characterizations. Image 1 • The combined material of CNTs and graphite is flexible, porous and well-conductive. • The material exhibits leading rate performance and cyclic stability. • Mechanism of CNTs growth and potassium storage is also studied. [ABSTRACT FROM AUTHOR]