从LaNiO的B位掺杂出发，采用溶胶-凝胶法制备了一系列掺杂co和Fe离子的高催化活性的LaNj-Co（Fe）vC，型钙钛矿电催化剂。并进一步研究了催化剂对于氧还原反应和氧析出反应的电催化性能。筛选出最佳催化活性的催化剂一将LaNiOxFe03和LaNio催化剂制备的双功能氧电极初步应用于MH-空气蓄电池：结果表明：使用较高催化活性的LaNi0为氧电极催化剂的电池性能比使用LaNi08Fe203为催化剂的电池高，但是电池放电容量的衰减比LaNiFe203为催化剂的电池大。这是由于钙钛矿催化剂晶格内的co离子不如Fe离子稳定造成的，两种催化剂制备的双功能氧电极都在152 h的充放电循环时间内保持了比较好的工作状态。

双功能氧电极的开发是二次空气电池的关键问题。以开发高性能的双功能氧电极为目的，制备了LaNiM、O（M=Co.Fe；y=0，0.2）钙钛矿氧化物作为双功能氧电极的电催化剂，以活性碳为栽体，聚四氟乙烯乳液为粘接剂制备双功能氧电极，采用三电极体系测试了氧电极的稳态极化曲线和电化学交流阻抗谱，并对其阴极极化和阳极极化的交流阻抗谱图进行分析，通过等效电路的拟舍研究了该系列双功能氧电极氧还原反应的工作机理。结果表明，对于LaNi0化舍物，B位掺杂可显著提高催化剂的电催化性能，电极氧还原反应的极化主要由电荷转移反应和Nernstian扩散过程造成。

Treated FeS2 samples were prepared by natural FeS2 samples which were ground first, heated in nitrogen and then washed in acid. The levels of impurity elements, primarily present asmetallic oxides and sulfides, are higher in the natural FeS than those in the treated sample. Scan-ning electron microscopy shows that the grain sizes of treated FeS:, particles are smaller than thoseof natural FeS2 particles. The electrochemical performance of Li/treated FeS2 cells is attributed tothe smaller grain sizes and higher purity of treated FeS particles in comparison to the natural FeSsample.

Olivine-type LiFePO4/C composite cathode materials were synthesized by a solid-state reaction methodin an inert atmosphere. The glucose was added as conductive precursors before the formation of the crystallinephase. The effects of glucose content on the properties of as-synthesized cathode materials were investigated. Thecrystal structure and the electrochemical performance were characterized by X-ray diffraction (XRD), scanningelectron microscopy (SEM), laser particle-size distribution measurement and electrochemical performance testing. The material has a single crystal olivine structure with grain-sizes ca. 100-200rim. SEM micrographs and thecorresponding energy dispersive spectrometer (EDS) data confirm that the carbon particulates produced by glucosepyrogenation are uniformly dispersed among the LiFePO4 grains, ensuring a good electronic contact. Impedancespectroscopy was used to investigate the ohmic and kinetic contributions to the cell performance. It is found thatincreasing the carbon content leads to a reduction of the cell impedance due to the reduction of the charge transferresistance. The galvanostaticaUy charge and discharge tests show that the material obtained by adding 10% C (bymass) gives a maximum discharge capacity of 140.8mA. h. g, 1 at the same rate (C/10). The material also displaysa more stable cycle-life than the others.

Some rare earth doping spinel LiMn2-RE, Oa(RE=La, Ce, Nd) cathode materials for lithium ion batteries were synthesized by the solid-state reaction method. "File structure characteristics of these produced samples were investi-gated by XRD, SEM, and particle size distribution analysis. According to the microstructure and charge-discharge testing, the effect of doping rare earth on stabilizing the spinel structure was analyzed. Through a series of doping experiments, it is shown that when the doping content x within the range of 0. 01～0. 02 the cycle performance of the materials is greatly improved. The discharge capacity of the sample LiMnl 9sLao. o204, LiMnl 9sCe0 0204 and LiMni 98Nd0 0204 remain 119. 1, 114. 2 and 117. 5mAh'g-i after 50 cycles.