Electrochemical comparison of LiFe0.4Mn0.595Cr0.005PO4/C and LiMnPO4/C cathode materials

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• 作者：Yuanyuan Cai ; Dongyun Zhang ; Chengkang Chang ; Zhaomin Sheng ; Kejun Huang
• 刊名：Ionics
• 出版年：2016
• 出版时间：July 2016
• 年：2016
• 卷：22
• 期：7
• 页码：1011-1019
• 全文大小：4,656 KB
• 刊物类别：Chemistry and Materials Science
• 刊物主题：Chemistry
  Electrochemistry
  Materials Science
  Physical Chemistry
  Condensed Matter
  Renewable Energy Sources
  Electrical Power Generation and Transmission
  
• 出版者：Springer Berlin / Heidelberg
• ISSN：1862-0760
• 卷排序：22

文摘

A comparison of electrochemical performance between LiFe_0.4Mn_0.595Cr_0.005PO₄/C and LiMnPO₄/C cathode materials was conducted in this paper. The cathode samples were synthesized by a nano-milling-assisted solid-state process using caramel as carbon sources. The prepared samples were investigated by XRD, SEM, TEM, energy-dispersive X-ray spectroscopy (EDAX), powder conductivity test (PCT), carbon-sulfur analysis, electrochemical impedance spectroscopy (EIS), and galvanostatic charge-discharge cycling. The results showed that LiFe_0.4Mn_0.595Cr_0.005PO₄/C exhibited high specific capacity and high energy density. The initial discharge capacity of LiFe_0.4Mn_0.595Cr_0.005PO₄/C was 163.6 mAh g−1 at 0.1C (1C = 160 mA g−1), compared to 112.3 mAh g−1 for LiMnPO₄/C. Moreover, the Fe/Cr-substituted sample showed good cycle stability and rate performance. The capacity retention of LiFe_0.4Mn_0.595Cr_0.005PO₄/C was 98.84 % over 100 charge-discharge cycles, while it was only 86.64 % for the pristine LiMnPO₄/C. These results indicated that Fe/Cr substitution enhanced the electronic conductivity for the prepared sample and facilitated the Li+ diffusion in the structure. Furthermore, LiFe_0.4Mn_0.595Cr_0.005PO₄/C composite presented high energy density (606 Wh kg−1) and high power density (574 W kg−1), thus suggested great potential application in lithium ion batteries (LIBs).KeywordsCathode materialsElectrochemical performanceEnergy densityCycle stability