The core-shell Li4Ti5O（12） @ polyaniline composites（LP） have been synthesized via an in situ synthesis with different mole ratios（25：1, 50：1 and 100：1, aniline：LTO）. As an anode material of lithium-ion batte...The core-shell Li4Ti5O（12） @ polyaniline composites（LP） have been synthesized via an in situ synthesis with different mole ratios（25：1, 50：1 and 100：1, aniline：LTO）. As an anode material of lithium-ion batteries,the LP-2 electrodes（50：1） exhibit a high initial reversible capacity of 205 mAh g^（-1）with an initial coulombic efficiency of 97.6% at 0.1 C. Even at a high current density of 10 C, the reversible capacity of the LP-2 electrodes still remains at 102 mAh g^（-1）. Moreover, the LP-2 electrodes retain an impressive high capacity of 161 mAh g^（-1）after 100 cycles at 1 C, with 0.11% capacity fading per cycle. The promising electrochemical performance may be attributed to the significantly decreasing charge-transfer impedance of the LP composite and reductive polarity difference between the cathode and the electrolyte.展开更多
Composite polymer electrolytes（CPEs） comprising poly（vinilydene fluoride-hexafluoro propylene）, PVDF-coHFP and zinc triflate, Zn（CF3SO3）2 with varying concentrations of ZrO_2 nanofillers were prepared by solutio...Composite polymer electrolytes（CPEs） comprising poly（vinilydene fluoride-hexafluoro propylene）, PVDF-coHFP and zinc triflate, Zn（CF3SO3）2 with varying concentrations of ZrO_2 nanofillers were prepared by solution casting technique with N,N-dimethyl formamide（DMF） as the common solvent. The polymer electrolyte specimen with the particular composition 75 wt% PVDF-co-HFP： 25 wt% Zn Tf ＋ 7 wt% Zr O2 showed the highest conductivity of 4.6 × 10-4 S/cm at 298 K as confirmed from impedance measurements and favored by the rich amorphous phase of the CPE revealed from room temperature X-ray diffraction analysis（XRD）. The electrical conductivity relaxation time and its distribution within the materials have been evaluated from the electric modulus M 2 and impedance Z＂ data which showed the occurrence of non-Debye type of relaxation phenomenon. The changes in the surface morphology of the CPEs were examined using scanning electron microscopy（SEM）. The electrochemical stability window of CPE is found to be 2.6 V with a thermal stability up to 300 °C. An electrochemical cell has been fabricated based on Zn/MnO_2 electrode couple under a constant load of 1 MΩ and its discharge characteristics have been evaluated.展开更多
基金supported by the “973” Special Preliminary Study Plan (No. 2014CB260411)the National Key Technology R&D Program (No. 2013BAF09B02)+2 种基金the National Natural Science Foundation of China (No. 51472152)the Innovation Team Assistance Foundation of Shaanxi Province (No. 2013KCT-06)the Graduate Innovation Fund of Shaanxi University of Science and Technology
文摘The core-shell Li4Ti5O（12） @ polyaniline composites（LP） have been synthesized via an in situ synthesis with different mole ratios（25：1, 50：1 and 100：1, aniline：LTO）. As an anode material of lithium-ion batteries,the LP-2 electrodes（50：1） exhibit a high initial reversible capacity of 205 mAh g^（-1）with an initial coulombic efficiency of 97.6% at 0.1 C. Even at a high current density of 10 C, the reversible capacity of the LP-2 electrodes still remains at 102 mAh g^（-1）. Moreover, the LP-2 electrodes retain an impressive high capacity of 161 mAh g^（-1）after 100 cycles at 1 C, with 0.11% capacity fading per cycle. The promising electrochemical performance may be attributed to the significantly decreasing charge-transfer impedance of the LP composite and reductive polarity difference between the cathode and the electrolyte.
基金financially supported by the National Centre for Nanoscience and Nanotechnology,University of Madras for SEM analysis and financial assistance received in the form of a research grant
文摘Composite polymer electrolytes（CPEs） comprising poly（vinilydene fluoride-hexafluoro propylene）, PVDF-coHFP and zinc triflate, Zn（CF3SO3）2 with varying concentrations of ZrO_2 nanofillers were prepared by solution casting technique with N,N-dimethyl formamide（DMF） as the common solvent. The polymer electrolyte specimen with the particular composition 75 wt% PVDF-co-HFP： 25 wt% Zn Tf ＋ 7 wt% Zr O2 showed the highest conductivity of 4.6 × 10-4 S/cm at 298 K as confirmed from impedance measurements and favored by the rich amorphous phase of the CPE revealed from room temperature X-ray diffraction analysis（XRD）. The electrical conductivity relaxation time and its distribution within the materials have been evaluated from the electric modulus M 2 and impedance Z＂ data which showed the occurrence of non-Debye type of relaxation phenomenon. The changes in the surface morphology of the CPEs were examined using scanning electron microscopy（SEM）. The electrochemical stability window of CPE is found to be 2.6 V with a thermal stability up to 300 °C. An electrochemical cell has been fabricated based on Zn/MnO_2 electrode couple under a constant load of 1 MΩ and its discharge characteristics have been evaluated.
