Lithium Storage Performance of Hard Carbons Anode Materials Prepared by Different Precursors

Authors

Zhen-Lang Liang, Department of New Energy Materials and Devices, School of Materials and Energy, Guangdong University of Technology, Guangzhou 510000, Guangdong, China;
Yao Yang, Department of New Energy Materials and Devices, School of Materials and Energy, Guangdong University of Technology, Guangzhou 510000, Guangdong, China;
Hao Li, Department of New Energy Materials and Devices, School of Materials and Energy, Guangdong University of Technology, Guangzhou 510000, Guangdong, China;
Li-Ying Liu, Department of New Energy Materials and Devices, School of Materials and Energy, Guangdong University of Technology, Guangzhou 510000, Guangdong, China;
Zhi-Cong Shi, Department of New Energy Materials and Devices, School of Materials and Energy, Guangdong University of Technology, Guangzhou 510000, Guangdong, China;Follow

Corresponding Author

Zhi-Cong Shi(zhicong@gdut.edu.cn)

Abstract

Hard carbon is one of the most promising anode material for lithium ion batteries (LIBs) owing to its high stability, widespread availability, low-cost, and excellent performance. The electrochemical properties of hard carbon materials depend strongly on the type of precursors. It is, therefore, very important to choose an excellent hard carbon precursor. Polyacrylonitrile, petroleum pitch and peanut shells were used as raw materials to prepare different hard carbon anode materials for LIBs. These hard carbon anode materials were successfully synthesized in two steps. The selected precursor was firstly carbonized at 600℃ for 1 h in argon atmosphere using heating rate of 1℃·min^-1, and then was further carbonized at 1200℃ for 1h in argon atmosphere using heating rate of 5℃·min^-1. Under such a low heating rate, a relatively small specific surface area could be obtained as much as possible for the hard carbon anode material. The surface morphology and phase structure of as synthesized hard carbon materials were analyzed by scanning electron microscopy, X-ray diffractometer, nitrogen adsorption analyzer and Raman spectrometer. The ion carrier storage mechanism was further investigated using cyclic voltammetry by examining whether the ion insertion/extraction mechanism is surface-controlled pseudocapacitance or diffusion-limited intercalation. It was further verified that the lithium storage mechanism of hard carbon anode materials is in line with the “adsorption-intercalation” mechanism. The results indicated that polyacrylonitrile-derived hard carbon anode material had low impedance by EIS test. This may be the reason why the low voltage platform of polyacrylonitrile-derived hard carbon materials had a higher specific capacity. The electrochemical performance of different hard carbon materials were investigated through galvanostatic charge and discharge tests. The peanut shell-derived hard carbon material showed the highest initial specific capacity (579.1 mAh·g^-1), but the lowest initial coulombic efficiency (49.35%). The petroleum pitch-derived one delivered the highest initial coulombic efficiency (85.97%), but the lowest initial specific capacity (301.7 mAh·g^-1). Comparing the cycle performance of these three hard carbon materials, polyacrylonitrile-derived hard carbon materials exhibited the excellent cycling performance (87.17% of capacity over 500 cycles). This study would provide useful assistance to understand the precursor-derived electrochemical properties of hard carbon anode material in practical applications.

Graphical Abstract

Keywords

lithium ion battery, anode material, hard carbon, electrochemical performance

DOI Link

https://doi.org/10.13208/j.electrochem.201242

Publication Date

2021-04-28

Online Available Date

2021-02-18

Revised Date

2021-01-22

Received Date

2021-01-02

Recommended Citation

Zhen-Lang Liang, Yao Yang, Hao Li, Li-Ying Liu, Zhi-Cong Shi. Lithium Storage Performance of Hard Carbons Anode Materials Prepared by Different Precursors[J]. Journal of Electrochemistry, 2021 , 27(2): 177-184.
DOI: Hard carbon is one of the most promising anode material for lithium ion batteries (LIBs) owing to its high stability, widespread availability, low-cost, and excellent performance. The electrochemical properties of hard carbon materials depend strongly on the type of precursors. It is, therefore, very important to choose an excellent hard carbon precursor. Polyacrylonitrile, petroleum pitch and peanut shells were used as raw materials to prepare different hard carbon anode materials for LIBs. These hard carbon anode materials were successfully synthesized in two steps. The selected precursor was firstly carbonized at 600℃ for 1 h in argon atmosphere using heating rate of 1℃·min^-1, and then was further carbonized at 1200℃ for 1h in argon atmosphere using heating rate of 5℃·min^-1. Under such a low heating rate, a relatively small specific surface area could be obtained as much as possible for the hard carbon anode material. The surface morphology and phase structure of as synthesized hard carbon materials were analyzed by scanning electron microscopy, X-ray diffractometer, nitrogen adsorption analyzer and Raman spectrometer. The ion carrier storage mechanism was further investigated using cyclic voltammetry by examining whether the ion insertion/extraction mechanism is surface-controlled pseudocapacitance or diffusion-limited intercalation. It was further verified that the lithium storage mechanism of hard carbon anode materials is in line with the “adsorption-intercalation” mechanism. The results indicated that polyacrylonitrile-derived hard carbon anode material had low impedance by EIS test. This may be the reason why the low voltage platform of polyacrylonitrile-derived hard carbon materials had a higher specific capacity. The electrochemical performance of different hard carbon materials were investigated through galvanostatic charge and discharge tests. The peanut shell-derived hard carbon material showed the highest initial specific capacity (579.1 mAh·g^-1), but the lowest initial coulombic efficiency (49.35%). The petroleum pitch-derived one delivered the highest initial coulombic efficiency (85.97%), but the lowest initial specific capacity (301.7 mAh·g^-1). Comparing the cycle performance of these three hard carbon materials, polyacrylonitrile-derived hard carbon materials exhibited the excellent cycling performance (87.17% of capacity over 500 cycles). This study would provide useful assistance to understand the precursor-derived electrochemical properties of hard carbon anode material in practical applications.