High-power rhombohedral-Fe2(SO4)3 with outstanding cycle-performance as Fe-based cathode for K-ion batteries

Jungmin Kang; Wonseok Ko; Hyunyoung Park; Yongseok Lee; Jae Hyeon Jo; Ji Ung Choi; Seung Taek Myung; Jongsoon Kim

doi:10.1016/j.ensm.2020.08.024

High-power rhombohedral-Fe₂(SO₄)₃ with outstanding cycle-performance as Fe-based cathode for K-ion batteries

Jungmin Kang
, Wonseok Ko
, Hyunyoung Park
, Yongseok Lee
, Jae Hyeon Jo
, Ji Ung Choi
, Seung Taek Myung
, Jongsoon Kim

Sejong University

Research output: Contribution to journal › Article › peer-review

15 Scopus citations

Abstract

We report rhombohedral-Fe₂(SO₄)₃ as a promising cathode material for potassium-ion batteries. Detailed structure information for rhombohedral-Fe₂(SO₄)₃ was obtained using X-ray diffraction with Rietveld refinement. Based on the structural information, possible atomic sites for K ions and ion diffusion pathway in the structure were determined using bond-valence energy landscape analyses. At C/20 (1C = 112 mA g⁻¹), rhombohedral-K_xFe₂(SO₄)₃ delivered a specific capacity of ~100 mAh g⁻¹ an average operation voltage of ~3.3 V (vs. K⁺/K), corresponding to reversible de/intercalation of ~1.78 mol K⁺ ions. Moreover, even at 5C, rhombohedral-K_xFe₂(SO₄)₃ exhibited capacity retention of ~80% of the capacity measured at C/20, indicating the outstanding power-capability. After 300 cycles at 2C, rhombohedral-K_xFe₂(SO₄)₃ maintained ~83% of its initial specific capacity with high Coulombic efficiency of more than 99%. Operando XRD analyses revealed that the XRD peaks of rhombohedral K_xFe₂(SO₄)₃ monotonously shifted during K⁺ de/intercalation, indicating a single phase reaction. First-principles calculation confirmed the good agreement between the theoretical properties of rhombohedral-K_xFe₂(SO₄)₃ and the experimental results, including the average operation voltage, power-capability, and phase reaction.

Original language	English
Pages (from-to)	276-282
Number of pages	7
Journal	Energy Storage Materials
Volume	33
DOIs	https://doi.org/10.1016/j.ensm.2020.08.024
State	Published - Dec 2020
Externally published	Yes

Keywords

Cathode
First principle calculations
High power-capability
K-ion batteries
Rhombohedral-Fe(SO)

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Access to Document

10.1016/j.ensm.2020.08.024

Cite this

@article{9b01f96ee140496da10d698702db6730,

title = "High-power rhombohedral-Fe2(SO4)3 with outstanding cycle-performance as Fe-based cathode for K-ion batteries",

abstract = "We report rhombohedral-Fe2(SO4)3 as a promising cathode material for potassium-ion batteries. Detailed structure information for rhombohedral-Fe2(SO4)3 was obtained using X-ray diffraction with Rietveld refinement. Based on the structural information, possible atomic sites for K ions and ion diffusion pathway in the structure were determined using bond-valence energy landscape analyses. At C/20 (1C = 112 mA g−1), rhombohedral-KxFe2(SO4)3 delivered a specific capacity of \textasciitilde{}100 mAh g−1 an average operation voltage of \textasciitilde{}3.3 V (vs. K+/K), corresponding to reversible de/intercalation of \textasciitilde{}1.78 mol K+ ions. Moreover, even at 5C, rhombohedral-KxFe2(SO4)3 exhibited capacity retention of \textasciitilde{}80\% of the capacity measured at C/20, indicating the outstanding power-capability. After 300 cycles at 2C, rhombohedral-KxFe2(SO4)3 maintained \textasciitilde{}83\% of its initial specific capacity with high Coulombic efficiency of more than 99\%. Operando XRD analyses revealed that the XRD peaks of rhombohedral KxFe2(SO4)3 monotonously shifted during K+ de/intercalation, indicating a single phase reaction. First-principles calculation confirmed the good agreement between the theoretical properties of rhombohedral-KxFe2(SO4)3 and the experimental results, including the average operation voltage, power-capability, and phase reaction.",

keywords = "Cathode, First principle calculations, High power-capability, K-ion batteries, Rhombohedral-Fe(SO)",

author = "Jungmin Kang and Wonseok Ko and Hyunyoung Park and Yongseok Lee and Jo, \{Jae Hyeon\} and Choi, \{Ji Ung\} and Myung, \{Seung Taek\} and Jongsoon Kim",

note = "Publisher Copyright: {\textcopyright} 2020 Elsevier B.V.",

year = "2020",

month = dec,

doi = "10.1016/j.ensm.2020.08.024",

language = "English",

volume = "33",

pages = "276--282",

journal = "Energy Storage Materials",

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publisher = "Elsevier B.V.",

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T1 - High-power rhombohedral-Fe2(SO4)3 with outstanding cycle-performance as Fe-based cathode for K-ion batteries

AU - Kang, Jungmin

AU - Ko, Wonseok

AU - Park, Hyunyoung

AU - Lee, Yongseok

AU - Jo, Jae Hyeon

AU - Choi, Ji Ung

AU - Myung, Seung Taek

AU - Kim, Jongsoon

PY - 2020/12

Y1 - 2020/12

N2 - We report rhombohedral-Fe2(SO4)3 as a promising cathode material for potassium-ion batteries. Detailed structure information for rhombohedral-Fe2(SO4)3 was obtained using X-ray diffraction with Rietveld refinement. Based on the structural information, possible atomic sites for K ions and ion diffusion pathway in the structure were determined using bond-valence energy landscape analyses. At C/20 (1C = 112 mA g−1), rhombohedral-KxFe2(SO4)3 delivered a specific capacity of ~100 mAh g−1 an average operation voltage of ~3.3 V (vs. K+/K), corresponding to reversible de/intercalation of ~1.78 mol K+ ions. Moreover, even at 5C, rhombohedral-KxFe2(SO4)3 exhibited capacity retention of ~80% of the capacity measured at C/20, indicating the outstanding power-capability. After 300 cycles at 2C, rhombohedral-KxFe2(SO4)3 maintained ~83% of its initial specific capacity with high Coulombic efficiency of more than 99%. Operando XRD analyses revealed that the XRD peaks of rhombohedral KxFe2(SO4)3 monotonously shifted during K+ de/intercalation, indicating a single phase reaction. First-principles calculation confirmed the good agreement between the theoretical properties of rhombohedral-KxFe2(SO4)3 and the experimental results, including the average operation voltage, power-capability, and phase reaction.

AB - We report rhombohedral-Fe2(SO4)3 as a promising cathode material for potassium-ion batteries. Detailed structure information for rhombohedral-Fe2(SO4)3 was obtained using X-ray diffraction with Rietveld refinement. Based on the structural information, possible atomic sites for K ions and ion diffusion pathway in the structure were determined using bond-valence energy landscape analyses. At C/20 (1C = 112 mA g−1), rhombohedral-KxFe2(SO4)3 delivered a specific capacity of ~100 mAh g−1 an average operation voltage of ~3.3 V (vs. K+/K), corresponding to reversible de/intercalation of ~1.78 mol K+ ions. Moreover, even at 5C, rhombohedral-KxFe2(SO4)3 exhibited capacity retention of ~80% of the capacity measured at C/20, indicating the outstanding power-capability. After 300 cycles at 2C, rhombohedral-KxFe2(SO4)3 maintained ~83% of its initial specific capacity with high Coulombic efficiency of more than 99%. Operando XRD analyses revealed that the XRD peaks of rhombohedral KxFe2(SO4)3 monotonously shifted during K+ de/intercalation, indicating a single phase reaction. First-principles calculation confirmed the good agreement between the theoretical properties of rhombohedral-KxFe2(SO4)3 and the experimental results, including the average operation voltage, power-capability, and phase reaction.

KW - Cathode

KW - First principle calculations

KW - High power-capability

KW - K-ion batteries

KW - Rhombohedral-Fe(SO)

UR - https://www.scopus.com/pages/publications/85091195675

U2 - 10.1016/j.ensm.2020.08.024

DO - 10.1016/j.ensm.2020.08.024

M3 - Article

AN - SCOPUS:85091195675

SN - 2405-8297

VL - 33

SP - 276

EP - 282

JO - Energy Storage Materials

JF - Energy Storage Materials

ER -