铁电极活性粉的制备及其高倍率放电性能的研究

PREPARATION OF IRON ELECTRODE ACTIVE POWDER AND STUDY OF ITS HIGH RATE DISCHARGE BEHAVIOR

采用无机合成技术，通入Ｏ２及滴加ＮａＯＨ溶液，加热硫酸亚铁与ＮＨ４ＮＯ３的混合溶液使部分二价铁被氧化成三价，沉淀物经过滤和干燥后，在氩气氛下６７０℃焙烧１ｈ得到铁电极活性粉．经Ｘ射线衍射分析，该活性粉的成分是单相四氧化三铁．利用该活性粉所制备的铁电极，在不添加任何添加剂的条件下，以１００ｍＡ／ｇ放电的容量为２４５．５ｍＡ·ｈ／ｇ．该电极的高倍率放电性能好，以１２０ｍＡ／ｇ放电的容量为２１６ｍＡ·ｈ／ｇ．

Inorganic synthetic method has been used to prepare the active powder of iron electrode. The process is that the solution of FeSO 4 and NH 4NO 3 was heated wth the flow of O 2 and addition of NaOH solution for 1 hour. Then, the precipitate was filtered and dried, and the active powder was obtained after the precipitate was heated in argon gas at 670℃ for 1 hour. The XRD analysis shows that the active powder is single phase of Fe 3O 4. The discharge capacity of the iron electrode made of the powder was 245.5 mA·h/g at 100 mA/g. The electrode shows good behavior at high discharge rate and can be discharged under the current of 1200 mA/g with the capacity of 216 mA·h/g.