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Abstract: Tin phosphide (Sn4P3) with a layered structure was synthesized by direct ball-milling method and tested for possible use as an electroactive anode material in alkaline aqueous solution. The experimental results demonstrated that the Sn4P3 electrode could deliver a discharge capacity of 775mAh/g at the constant current of 200mA/g, 716mAh/g at 2000mA/g and 511mAh/g at 5000mA/g respectively, showing a superiorly high rate capability in alkaline aqueous solution. The excellent electrochemical activity of the Sn4P3 material is found to arise from the cooperative interaction of the P and Sn atoms in the layered crystalline structure, in which the Sn atom layers serve as a conductive framework providing an electronic passage for the 5-electron oxidation of the P atoms. [Copyright &y& Elsevier]

A novel positive-temperature-coefficient (PTC) electrode was prepared by coating a thin layer of epoxy-carbon PTC material in between the electroactive LiCoO2 layer and the electrode substrate and used for self-actuating thermal cut-off of Li-ion batteries when the batteries are overheated. Experimental results from cyclic voltammetry, impedance spectrometry and charge–discharge measurements demonstrate that the PTC electrode exhibits normal electrochemical behaviors at ambient temperature, but shows an enormous increase in the resistance at the temperature range of 100–130 °C. This PTC behavior of the electrode provides a current-limiting effect, acting as a reversible thermal shutdown switch for rechargeable lithium batteries. [Copyright &y& Elsevier]

A Na-rich poly(diphenylaminesulfonic acid sodium) (PDS) is prepared by oxidative polymerization and tested as an organic Na-host cathode for Na-ion batteries. Due to the highly self-doped benzenesulfonic anions grafted on the polyaniline backbones, this redox-active polymer demonstrates a reversible capacity of 100 mAh g − 1 at an average potential of ~ 3.4 V, reaching its theoretical value of reversible 1 Na insertion/extraction reaction. In addition, this polymer cathode also exhibits considerable rate capability and cycling stability, possibly serving as a low cost and sustainable cathode of Na-ion batteries for widespread electric storage applications. [ABSTRACT FROM AUTHOR]

Abstract: A new fire retardant-dimethyl methyl phosphate (DMMP) was tested as a nonflammable electrolyte solvent for Li-ion batteries. It is found that in the addition of chloro-ethylene carbonate (Cl-EC) as an electrolyte additive, the electrochemical reduction of DMMP molecules can be completely suppressed and the graphite anode can be cycled very well with high initial columbic efficiency (∼84%) and excellent cycling stability in the DMMP electrolyte. The prismatic C/LiCoO2 batteries using 1.0molL−1 LiClO4 +10% Cl-EC+DMMP electrolyte exhibited almost the same charge and discharge performances as those using conventional carbonate electrolytes, suggesting a feasible use of this new electrolyte for constructing nonflammable Li+-ion batteries. [Copyright &y& Elsevier]

Abstract: FeSi6/graphite composite was prepared by mechanical ball milling. The FeSi6 alloy particles consist of an electrochemically active silicon phase and inactive phases FeSi2, distributed uniformly in the graphite matrix. The composite anode offers a large reversible capacity (about 800mAhg−1) and good cycleability, due to the buffering effect of the inactive FeSi2 phase and graphite layers on the volumetric changes of Si phase during lithium–Si alloying reaction. Since FeSi6 alloy is a low-cost industrial material, this alloy compound provides a possible alternative for development of high capacity lithium-ion batteries. [Copyright &y& Elsevier]

Abstract: Polytriphenylamine (PTPAn) was chemically synthesized and tested as a cathode material for high-rate storage and delivery of electrochemical energy. It is found that the polymer has not only superior high power capability but also high energy density at prolonged cycling. At a moderate rate of 0.5C, PTPAn gives a high average discharge voltage of 3.8V and quite a high capacity of 103mAhg−1, which is very close to the theoretical capacity (109mAhg−1) as expected from one electron transfer per triphenylamine monomer. Even cycled at a very high rate of 20C, the polymer can still deliver a capacity of 90mAhg−1 at 1000th cycle with a nearly 100% coulombic efficiency. The excellent electrochemical performances of PTPAn are explained from the structural specificity of the polymer where the radical redox centers are stabilized and protected by conductive polymeric backbone, making the radical redox and charge-transporting processes kinetically facile for high-rate charge and discharge. [Copyright &y& Elsevier]

Abstract: Dimethyl methyl phosphonate (DMMP) was selected and tested as a non-flammable solvent for primary and secondary lithium batteries, because of its non-flammability, good solvency of lithium salts and appropriate liquidus properties. Experimental results demonstrated that DMMP can solvate considerable amount of commonly used lithium salts to form non-flammable and Li+-conducting electrolyte, which has very wide electrochemical window (>5V vs. Li) and excellent electrochemical compatibility with metallic lithium anode and oxide cathodes. Primary Li–MnO2 cells using DMMP-based electrolyte showed almost the same discharge performances as those using organic carbonate electrolytes, and also, Li–LiMn2O4 cells using DMMP electrolyte exhibited greatly improved cycleability and dischargeability, suggesting a feasible application of this new electrolyte for constructing high performance and non-flammable lithium batteries. [Copyright &y& Elsevier]

Abstract: A compound 4-tertbutyl-1,2-dimethoxybenzene (TDB) was synthesized and tested as a redox shuttle for overcharge protection of Li–LiFePO4 batteries. This isomer of tertbutyl-substituted dimethoxybenzene is miscible with the organic polar electrolytes and provides a solution for the poor solubility of ditertbutyl-substituted 1,4-dimethoxybenzenes as a redox shuttle additive. The experimental results demonstrated that the shuttle molecules added in the electrolyte cannot only provide feasible overcharge protection, but also have indiscernible detrimental influences on the charge–discharge behaviors of Li–LiFePO4 cells, showing a great prospect for practical applications in commercial rechargeable lithium batteries. [Copyright &y& Elsevier]

Abstract: A series of VB x (x =0.1, 0.25, 0.5, and 1) are prepared by a mechanochemical reaction of elemental B and V powders and tested as alternative high capacity anodic materials for alkaline air batteries. The VB x (x =0.25, 0.5, and 1) anodes tested can deliver an extraordinary capacity of >2000mAhg−1, twice higher than the theoretical capacity of metallic Zn currently used as high capacity anodes in aqueous primary batteries. The strong discharge capabilities observed from electrochemically inert boron (B) and passive vanadium (V) in the VB x samples are suggested to result from a combined chemical interaction, in which the B atoms are electrochemically activated by bonding with V atoms to partially decrease the covalent stability of elemental B component. At the same time, the electrochemically activated B can alleviate, in turn, the anodic polarization of metallic V element by clamping the electrode potential to a region where elemental V is in active state. [Copyright &y& Elsevier]