To provide a high performance and highly reliable β-alumina ceramics free from the occurrence of surface deterioration or surface defects which are caused by moisture adsorption occurred while a battery assembly is completed after firing, especially rapid desorption of excess moisture from the surface of the β-alumina ceramics by heat treating and rapid re-adsorption of moisture after heat treatment, a method for producing the same and a solid electrolyte- type battery using the ceramics.
The β-alumina ceramics is formed into a prescribed shape by grinding using an aqueous grinding liquid and the shaped β-alumina ceramics is heat-treated at ≤200°C so that the amount of the moisture adsorbed is controlled to ≤0.7 mg/cm2. Then, the β-alumina ceramics wherein the moisture content is controlled in a prescribed range is stored in an atmosphere having a relative humidity of ≤40%. It is preferable that the change rate of the amount of adsorbed moisture is ≤50% after the β-alumina ceramics wherein the moisture content is controlled to ≤0.7 mg/cm2 is stored in an atmosphere having the relative humidity of ≤40% for ten days.
UEMATSU HIDEKI
IIO SATOSHI
