Shi Peng-fei

Studies on the anodic behavior of aluminum electrodes in alkaline solution

Abstract An efficient process for developing aluminum alloys for alkaline battery anodes is described. The addition of gallium to aluminum eliminates remarkably the anisotropy of aluminum, and thus renders its electrode potential more negative. The uniform distribution of alloying elements is an essential factor for lowering the corrossion rate of the alloy. The accumulation of an alloying element at intergranular bounderies, or the formation of a secondary phase that contains the element, will result in a rise in the corrosion rate of aluminum.

Characterization of ionic conducting cross-linked polyether electrolytes

An appropriate amount of toluene 2,4-diisocyanate (TDI) was added into polyether ([(CH2 CH2O)13CH2O]n)]Li salt electrolyte to form a cross-linked network, with improving the film processability and thermal stability. The relation between the structure and ionic conductive properties of the cross-lined polyether electrolytes was investigated by means of Fourier transform infra-red spectroscopy (FTIR), differential scanning calorimetry (DSC), mechanical property and AC impedance spectroscopy. The electrolytes system is found to have two glass transitions, and it is found that the two Tgs increase with increasing salt concentration. At the same Li salt concentration, the conductivity of cross-linked polyether/LiN(CF3SO2)2 complex system is higher than that of LiClO4. At EO/Li=25∶1(mol ratio), the former conductivity changes with temperature, while the later coincids with Arrhenius formula (σ=Ae−EalRT). The cross-linked polyether/LiN(CF3SO2)2 electrolyte exhibits the maximum σ=10−4.75 S/cm at 30°C.

Degradation mechanism of the misch metal alloy hydride electrodes

Abstract Pieces of nonpulverized misch metal (Mm) alloy were used as working electrodes (WEs). The WEs were cathodically charged in H2 and O2 atmospheres, respectively, and the electrode potentials were determined. The morphologies of definite areas of WEs were observed by SEM, and the surface composition in chemical elements of these areas were determined by EPMA. The results indicated that the main causes of the degradation of WEs might be the increase of internal stress, the expansion of crystal lattice, and the preferential dissolution of Mm during charging, rather than the oxidation of the alloy by O2, which was accordant with the presence of La3+ and Ni2+ in the MH electrode of MH/Ni batteries after cycling.