关键词: 热电池, 铁粉加热药, 半导体, 电导率

Abstract: The combustion products of thermal battery used iron-heated powders have been studied.It is identified by X-ray diffraction(XRD) analysis that the main compositions of the combustion products are Fe、FeO and KCl.The transmission electron microscopy(TEM) shows a typical core-shell structure with un-reacted Fe particle core coated by FeO shell with a shell thickness of around 200 nm.The combusted iron-heated powders exhibit no metal property,which is contrast to previous assumption.Further measurement indicates that at the ambient temperature the combustion products show semiconductor property of the p-type with conductivity in the order of 103 S·cm-1,which is five order lower than that of the iron at 800 K.Since the FeO layer formed during the iron-heated powders combustion is thin,its contribution to the internal resistance of the thermal batteries is negligible.

Key words: thermal battery, iron heat powder, semiconductor, electrical conductivity