CoS_2材料的纯化工艺优化及其在热电池中的应用

Optimization of purification technology and its application of CoS_2 in thermal battery

利用真空管式高温烧结法对CoS_2材料进行了热处理,以达到除去CoS_2材料中杂质硫的目的。采用SEM、XRD和TG-DSC对材料进行了微观形貌、晶相结构和热稳定性的测试,比较了不同纯化处理工艺对材料性能的影响。测试结果表明,500~560℃的高温烧结对CoS_2材料微观形貌影响较小,颗粒之间呈现一定的团聚现象,团聚体为微米级;550℃,18 h高温烧结后材料晶相结构发生了改变,变为Co3S4,550℃,10 h高温烧结后获得的材料仍为黄铁矿型CoS_2;550℃的高温烧结后CoS_2材料DSC曲线相对平滑,没有明显的杂质峰,具有最好的热稳定性。采用热电池活性检验单体电池自动放电系统对材料进行了电性能的测试,脉冲放电曲线的测试结果表明,CoS_2材料纯化处理后,整个放电过程中,其单体电池放电电压都明显提高,且具有更高的容量和更好的抗脉冲性能。

Heat treatment of CoS_2 was conducted in a vacuum tube furnace in order to get rid of impurity of sulfur. The morphology, crystal structure and thermal stability of CoS_2 was characterized by SEM, XRD and TG-DSC,respectively. The effect of process parameters on material properties was also studied. The test results show that morphologies of CoS_2 are changed slightly at the treated temperature of 500-560 ℃, and the aggregate about micro level appears between particles; the crystal structure of CoS 2 is changed to Co3 S4 at the treated temperature of 550 ℃for 18 h, which is maintained as pyrite CoS_2 treated for 10 h; DSC curves of CoS_2 treated at 550 ℃ shows smooth level without impurity peak. The automatic discharge system of single thermal battery was used for the electrical performance test. The pulse discharge curve shows that purified CoS 2 displays higher discharge voltage, larger capacity and better anti pulse performance.