【摘要】 二硫化铁 (黄铁矿 )是目前广泛使用的先进的LiSi FeS2 热电池的阴极 ,具有资源丰富、价格便宜、电化学性能优良等特点。但由于二硫化铁在热电池工作温度下 (5 0 0℃左右 )不稳定 ,成为研究长寿命热电池的一大障碍。为得到较稳定的二硫化铁 ,对它的晶体结构作了详细研究 ,指出该材料由三种晶形 (立方体、五角十二面体和八面体 )和两种导型 (n和p导型 )组成。目前国内外对混合型二硫化铁的电化学性质的研究比较深入并得到实际应用 ,但对各种纯净晶形和导型的二硫化铁的研究未见报道。本文对此已作了深入研究。指出 :五角十二面体 (n型 )二硫化铁具有较高的热稳定性和放电容量 ,但其开路电压和工作电压较低 ,适合于长寿命热电池使用。立方体 (p型 )和混合型二硫化铁 ,具有较低的热稳定性和放电容量 ,但开路电压和工作电压较高 ,适合于短寿命和中等寿命热电池使用。更多还原

【Abstract】 The FeS 2(pyrite) is a popular material used as cathode for advanced LiSi-FeS 2 thermal battery at present due to its advantages, such as abundant resource, low cost and good electrochemical characteristics. How- ever, the instability of FeS 2 at working temperature(about 500 ℃) make it a main hindrance for developing long-life thermal battery. The crystal structure of FeS 2 was studied for getting a stable material. The results show that FeS 2 material consists of three types of crystal structure(cubic crystal, pyritohedron crystal and octahedral crystal) and two conduction types(n type and p type). Up to date, the electrochemical characteristics of mixed FeS 2 have been studied deeply at home and abroad. However, the electrochemical characteristics of FeS 2 with different crystal structures have not been reported. The results of our study on the project indicated that the FeS 2 with pyritohedron crystal-structure(n type) performances higher thermal stability and discharge capacity while its open-circuit voltage and working voltage is lower than those of the FeS 2 with cubic crystal structure (p type) and the mixed FeS 2, thus it is suitable for the cathode material in long-life thermal battery. The FeS 2 with cubic crystal structure (p type) and the mixed FeS 2 have lower thermal stability and discharge capacity while their open-circuit voltage and working voltage are higher than that of the FeS 2 with pyritohedron crystal structure(n type), thus it is fit for cathode material in short-life and medium-life thermal battery.更多还原