| 摘要 |
PURPOSE:To prevent vessel melt-down in case solid electrolyte is damaged, by making a collector electrode of a metal of low melting point which is implanted in implanted in sodium negative electrode. CONSTITUTION:A negative electrode 2 is made of a material of low melting point. Due to the thermal conductivity of sodium, which is a metal, higher enough than that of sulfur, most part of heat generated by sodium-sulfur reaction is transmitted to the sodium side. In case a crack is generated in a solid electrolyte 3, the negative electrode 2 made of a material of low melting point immediately metals to be capable of shutting down the circuit between positive and negative electrodes. The material of the negative electrode 2 is required to have good electric conductivity and good corrosion resistance against sodium, as well as low melting point. Appropriate materials which satisfy these requirements are aluminum which has melting point at about 660 deg.C, aluminum- silicon-magnesium alloy which can have melting point lowered as low as near 600 deg.C, and others. |
