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The electroactive organic materialsare promising alternativesto inorganic electrode materials for the new generation of green Li-ionbatteries due to their sustainability, environmental benignity, andlow cost. Croconic acid disodium salt (CADS) was used as Li-ion batteryelectrode, and CADS organic wires with different diameters were fabricatedthrough a facile synthetic route using antisolvent crystallizationmethod to overcome the challenges of low electronic conductivity ofCADS and lithiation induced strain. The CADS nanowire exhibits muchbetter electrochemical performance than its crystal bulk materialand microwire counterpart. CADS nanowire with a diameter of 150 nmdelivers a reversible capability of 177 mAh g–1ata current density of 0.2 C and retains capacity of 170 mAh g–1after 110 charge/discharge cycles. The nanowire structure also remarkablyenhances the kinetics of croconic acid disodium salt. The CADS nanowireretains 50% of the 0.1 C capacity even when the current density increasesto 6 C. In contrast, the crystal bulk and microwire material completelylose their capacities when the current density merely increases to2 C. Such a high rate performance of CADS nanowire is attributed toits short ion diffusion pathway and large surface area, which enablefast ion and electron transport in the electrode. The theoreticalcalculation suggests that lithiation of CADS experiences an ion exchangeprocess. The sodium ions in CADS will be gradually replaced by lithiumions during the lithiation and delithiation of CADS electrode, whichis confirmed by inductively coupled plasma test. [ABSTRACT FROM AUTHOR]

Nano-Sn/C composites are ideal anode materials for highenergyand power density Li-ion batteries. However, because of the low meltingpoint of Sn and the tendency of grain growth, especially during hightemperature carbonization, it has been a significant challenge tocreate well-dispersed ultrasmall Sn nanoparticles within a carbonmatrix. In this paper, we demonstrate an aerosol spray pyrolysis technique,as a facile and scalable method, to synthesize a nano-Sn/C compositewith uniformly dispersed 10 nm nano-Sn within a spherical carbon matrix.The discharge capacity of nano-Sn/C composite sphere anodes maintainsthe initial capacity of 710 mAh/g after 130 cycles at 0.25 C. Thenano-Sn/C composite sphere anodes can provide ∼600 mAh/g evenat a high rate of 20 C. To the best of our knowledge, such high rateperformance for Sn anodes has not been reported previously. The exceptionalperformance of the nano-Sn/C composite is attributed to the uniquenano-Sn/C structure: (1) carbon matrix offers mechanical support toaccommodate the stress associated with the large volume change ofnano-Sn, thus alleviating pulverization; (2) the carbon matrix preventsSn nanoparticle agglomeration upon prolonged cycling; and (3) carbonnetwork provides continuous path for Li ions and electrons insidethe nano-Sn/C composite spheres. [ABSTRACT FROM AUTHOR]