铁与磷的比例对磷酸铁锂性能的影响  

Impact of Iron-to-Phosphorus Ratio on Properties of Lithium Iron Phosphate

作　　者：黄焕丰 谢彦宇 王长伟 邱松发 江佳明 曾德文[2] HUANG Huanfeng;XIE Yanyu;WANG Changwei;QIU Songfa;JIANG Jiaming;ZENG Dewen(Guangdong Guanghua Sci-tech Co.,Ltd.,Shantou 515000,China;College of Chemistry and Chemical Engineering,Central South University,Changsha 410083,China)

机构地区：[1]广东光华科技股份有限公司,广东汕头515000 [2]中南大学化学化工学院,湖南长沙410083

出　　处：《化工技术与开发》2025年第3期1-8,共8页Technology & Development of Chemical Industry

基　　金：国家重点研发计划青年科学家项目(2022YFC2906000)。

摘　　要：铁与磷的比例(Fe/P比)是磷酸铁锂正极材料的一项关键指标,对所制备的磷酸铁锂的压实密度、比容量、倍率性能、产品一致性等关键性能具有较大影响。本文通过调节磷酸铁前躯体中的Fe/P比,以及额外引入磷酸二氢锂等2种方式,探究了Fe/P比对磷酸铁锂性能的影响。结果表明,采用Fe/P比为0.975的磷酸铁前躯体,倾向于合成压实密度较低、比容量和倍率性能较高的磷酸铁锂;采用Fe/P比为0.97的磷酸铁前驱体,倾向于合成压实密度较高、比容量和倍率性能较低的磷酸铁锂。引入磷酸二氢锂会降低磷酸铁锂的Fe/P比,导致磷酸铁锂的压实密度降低,比容量和倍率性能降低。As a critical parameter in lithium iron phosphate cathode materials,the iron-to-phosphorus ratio(Fe/P ratio)plays a significant role in determining key performance metrics such as compaction density,specific capacity,rate capability,and product consistency of the synthesized lithium iron phosphate(LFP).This study investigates the impact of the Fe/P ratio on LFP properties through two experimental approaches:adjusting the Fe/P ratio by employing iron phosphate precursors with varying Fe/P ratios,and introducing lithium dihydrogen phosphate.When using a phosphate precursor with a Fe/P ratio of 0.975,the resulting lithium iron phosphate exhibits a lower compaction density but demonstrates higher specific capacity and enhanced rate capability.In contrast,precursors with a Fe/P ratio of 0.97 favor the synthesis of LFP with higher compaction density,albeit at the expense of specific capacity and rate capability.Furthermore,the addition of lithium dihydrogen phosphate to reduce the Fe/P ratio leads to decreased compaction density and specific capacity,along with a notable decline in rate capability.

关 键 词：磷酸铁锂 Fe/P比 正极材料 压实密度 

分 类 号：TM911[电气工程—电力电子与电力传动]