红外吸收法检测LiFePO_(4)/C的碳含量  

Determination of carbon content in LiFePO_(4)/C byinfrared absorption method

作　　者：王琳[1] 王楠[1] 王耀武 WANG Lin;WANG Nan;WANG Yaowu(Analysis and Measurement Centre of Northeastern University,Shenyang 110819,Liaoning,China;School of Metallurgy,Northeastern University,Shenyang 110819,Liaoning,China)

机构地区：[1]东北大学分析测试中心,辽宁沈阳110819 [2]东北大学冶金学院,辽宁沈阳110819

出　　处：《电池》2025年第2期396-401,共6页Battery Bimonthly

基　　金：国家重点研发计划项目(2021YFC2903205)。

摘　　要：基于自动进样-高频燃烧-红外吸收光谱原理,建立了宽范围测定碳包覆磷酸铁锂(LiFePO_(4)/C)正极材料中碳的方法。以某送检的LiFePO_(4)/C样品作为研究对象,通过SEM确定待测样品中碳的存在且分布相对均匀,探究称样量、助熔方式、分析参数和功率模式等实验条件,发现当称样量为0.0500 g,助熔方式为m(Fe)+m(W)=0.5000 g+0.7000 g,吹扫时间、延迟时间均为20 s,恒定功率模式(100%)时,结果可靠。方法的线性相关性(R 2)在低碳区、高碳区分别为0.9996、0.9990,检出限为0.0000596%,相对标准偏差(RSD,n=7)为0.80%~1.89%,样品的加标回收率为99.5%~101.5%。该方法的检测范围宽、准确性好、精密度高、自动化水平高。Based on the principle of automatic sampling-high frequency combustion-infrared absorption spectroscopy,a wide-range method for the determination of carbon in carbon-coated lithium iron phosphate(LiFePO_(4)/C)cathode materials is established.The LiFePO_(4)/C sample sent for inspection is taken as the research object,the presence and uniform distribution of carbon are proved by SEM,experimental conditions such as weighing sample size,fluxing mode,analysis parameters and power mode are explored.The experimental data are reliable when the sample weight is 0.0500 g,the fluxes are m(Fe)+m(W)=0.5000 g+0.7000 g,the purge time and delay time are 20 s and the constant power mode(100%)is used.The linear correlation(R 2)of the method is 0.9996(low carbon)/0.9990(high carbon),the detection limit is 0.0000596%,the relative standard deviation(RSD,n=7)is 0.80%-1.89%,the recovery rates of sample are 99.5%-101.5%.The method has a wide detection range,good accuracy,high precision and high automation levels.

关 键 词：红外吸收 助熔剂 正极材料 磷酸铁锂 碳包覆 碳含量 

分 类 号：TM912.9[电气工程—电力电子与电力传动] TD98[矿业工程—选矿]