Fast and Accurate Evaluation of LiFePO4 Cathode Materials by Single Particle Microelectrode

Authors

Fu-qing WANG, Contemporary Amperex Technology Limited, Ningde 352100, Fujian, China;
Yi-min WEI, Contemporary Amperex Technology Limited, Ningde 352100, Fujian, China;
Yu-zhuan SU, Contemporary Amperex Technology Limited, Ningde 352100, Fujian, China;
Bing-wei MAO, State Key Laboratory of Physical Chemistry of Solid Surfaces, Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, Fujian, China;
Kai WU, Contemporary Amperex Technology Limited, Ningde 352100, Fujian, China;
Feng-gang ZHAO, Contemporary Amperex Technology Limited, Ningde 352100, Fujian, China;
Chun-lei CHEN, State Key Laboratory of Physical Chemistry of Solid Surfaces, Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, Fujian, China;
Xing-lu LI, Contemporary Amperex Technology Limited, Ningde 352100, Fujian, China;
Jin CHONG, Contemporary Amperex Technology Limited, Ningde 352100, Fujian, China;Follow

Corresponding Author

Jin CHONG(ChongJ@ATLBattery.com)

Abstract

Single particle microelectrode enables to evaluate the electrochemical responses for single particle of active material without binder and conductive agent. Thus, the influences of additive and electrode structure on the electrochemical performance of active materials can be ignored. Furthermore, this technology can be used to evaluate active materials fast. Therefore, single particle microelectrode allows fast and accurate determination of the intrinsic performance of active material. Cyclic voltammogram (CV), cycle performance, and kinetic behavior of LiFePO4 cathode materials were evaluated by the single particle microelectrode. CV curve of LiFePO4 particle with a pair of oxidation and reduction peaks was obtained with scan rates of 20 mV?s-1, which is 400 times larger than that of composite electrode. Besides, it is found that Li+ diffusion in LiFePO4 particle is the bottleneck of electrochemical process, and the Li+ diffusion coefficient in LiFePO4 particle is about 2.4 ~ 3.2 ? 10-11 cm2?s-1. Excellent cycle performance was also proved to be the intrinsic properties of LiFePO4 cathode materials by single particle microelectrode. Therefore, single particle microelectrode is an effective method for evaluation of active materials for lithium ion batteries.

Graphical Abstract

Keywords

LiFePO4, single particle microelectrode, cyclic voltammograms, Li+ diffusion coefficient

DOI Link

https://doi.org/10.13208/j.electrochem.150714

Publication Date

2015-12-23

Online Available Date

2015-08-18

Revised Date

2015-08-04

Received Date

2015-07-14

Recommended Citation

Fu-qing WANG, Yi-min WEI, Yu-zhuan SU, Bing-wei MAO, Kai WU, Feng-gang ZHAO, Chun-lei CHEN, Xing-lu LI, Jin CHONG. Fast and Accurate Evaluation of LiFePO4 Cathode Materials by Single Particle Microelectrode[J]. Journal of Electrochemistry, 2015 , 21(6): 150714.
DOI: 10.13208/j.electrochem.150714
Available at: https://jelectrochem.xmu.edu.cn/journal/vol21/iss6/10