磷酸铁锂常温常压环境下时效性能研究

Aging properties of LiFePO_4 at normal temperature and pressure

对常温常压环境下保存1、30、180、360、720、1 080天的磷酸铁锂进行了研究。采用比色法比较不同时效样品Fe3+含量,化学滴定法测定不同时效样品LiOH、Li2CO3含量变化,并对不同时效样品进行了电化学性能测试。随保存时间的延长,Fe3+含量、LiOH和Li2CO3含量急剧增加,充/放电比容量降低,而且充电比容量降低得更多。

At normal temperature and pressure, the properties of LiFePO4 were studied during different aging time （1, 30, 180, 360, 720 and 1 080 days）. The content of Fe^3＋ with different aging time was examined by Colorimetry. The content of LiOH and Li2CO3 was characterized by chemical titration. The electrochemical properties of the samples with different aging time were investigated. With the increase of aging time, the content of Fe^3＋, LiOH and Li2CO3 dramatically increases, and the charge and discharge specific capacity greatly decreases, especially for charge specific capacity.