氯化物法制备MCFC隔膜用α-LiAlO_2细料的研究

INVESTIGATION ON FINE -LiAlO2 POWDER FOR MATRIX MATERIAL IN MCFC BY MEANS OF CHLORIDE SYNTHESIS

用氯化物法制得α－ＬｉＡｌＯ２细料．两种反应物料分别在６５０℃和５５０℃反应１ｈ，生成α－ＬｉＡｌＯ２．经过水洗等，产生水合作用，生成水合物（ＬｉＡｌＯ２）２·５Ｈ２Ｏ．此水合物失水后，又变为α－ＬｉＡｌＯ２细料．其粒度分别为０．３３μｍ和０．４５μｍ．反应物的粒度和性质及反应温度等对产物α－ＬｉＡｌＯ２粒度均有一定影响．在本方法中，吸入反应机理仍起主要作用．以此细和粗α－ＬｉＡｌＯ２粉料为原料，用流铸法制得电池隔膜．用此隔膜和两张烧结多孔Ｎｉ板组装的电池在２００ｍＡ／ｃｍ２放电时，输出电压为０．８５Ｖ．６次再起动。

Fine -LiAlO2 powder was prepared by Chloride synthesis and its hydrate (LiAlO2)25H2O was brought out by hydration of fine -LiAlO2 powder prepared upon the reaction of reactant A(or B) in the chloride at 650 (or 550 ) for 1 h. Its particle size is 0.33 m(or 0.45 m) and BET surface area is 140(or 124 )m2/g. The granularity of fine -LiAlO2 powder was dependent on the granularity and properties of reactants and reaction temperature and so forth. Imbibition mechanism still plays a significant factor in the Chloride synthesis. The matrix was prepared with the mixture of fine and coarse -LiAlO2 powder and by the flow cast. Its average pore diameter is 0.36 m and porosity is 64.4%. Cell voltage of MCFC(electrode area 28 cm2 or 110 cm2)assembled with the matrix and two sintered and porous Ni plates as anode and cathode is 0.854 V at 200 mA/cm2. The cell was operated for 6 thermal circles without reducing its performance.