Structural and electrochemical properties of Li 2Mn 0.5Fe 0.5SiO 4/C cathode nanocomposite

Youngmin Chung, Seung-Ho Yu, Min Seob Song, Sung Soo Kim, Won Il Cho

Research output: Contribution to journalArticle

9 Citations (Scopus)

Abstract

The Li 2Mn 0.5Fe 0.5SiO 4 silicate was prepared by blending of Li 2MnSiO 4 and Li 2FeSiO 4 precursors with same molar ratio. The one of the silicates of Li 2MnSiO 4 is known as high capacitive up to ∼330 mAh/g due to 2 mole electron exchange, and the other of Li 2FeSiO 4 has identical structure with Li 2MnSiO 4 and shows stable cycle with less capacity of ∼170 mAh/g. The major drawback of silicate family is low electronic conductivity (3 orders of magnitude lower than LiFePO 4). To overcome this disadvantage, carbon composite of the silicate compound was prepared by sucrose mixing with silicate precursors and heat-treated in reducing atmosphere. The crystal structure and physical morphology of Li 2Mn 0.5Fe 0.5SiO 4 was investigated by X-ray diffraction, scanning electron microscopy, and high resolution transmission electron microscopy. The Li 2Mn 0.5Fe 0.5SiO 4/C nanocomposite has a maximum discharge capacity of 200 mAh/g, and 63% of its discharge capacity is retained after the tenth cycles. We have realized that more than 1 mole of electrons are exchanged in Li 2Mn 0.5Fe 0.5SiO 4. We have observed that Li 2Mn 0.5Fe 0.5SiO 4 is unstable structure upon first delithiation with structural collapse. High temperature cell performance result shows high capacity of discharge capacity (244 mAh/g) but it had poor capacity retention (50%) due to the accelerated structural degradation and related reaction.

Original languageEnglish
Pages (from-to)4205-4209
Number of pages5
JournalBulletin of the Korean Chemical Society
Volume32
Issue number12
DOIs
Publication statusPublished - 2011 Dec 20
Externally publishedYes

Fingerprint

Silicates
Electrochemical properties
Structural properties
Nanocomposites
Cathodes
Electrons
High resolution transmission electron microscopy
Sucrose
Carbon
Crystal structure
X ray diffraction
Degradation
Scanning electron microscopy
Composite materials

Keywords

  • Cathode
  • Lithium manganese iron silicate
  • Lithium-ion battery
  • Physical blending
  • Polyanion system

ASJC Scopus subject areas

  • Chemistry(all)

Cite this

Structural and electrochemical properties of Li 2Mn 0.5Fe 0.5SiO 4/C cathode nanocomposite. / Chung, Youngmin; Yu, Seung-Ho; Song, Min Seob; Kim, Sung Soo; Cho, Won Il.

In: Bulletin of the Korean Chemical Society, Vol. 32, No. 12, 20.12.2011, p. 4205-4209.

Research output: Contribution to journalArticle

Chung, Youngmin ; Yu, Seung-Ho ; Song, Min Seob ; Kim, Sung Soo ; Cho, Won Il. / Structural and electrochemical properties of Li 2Mn 0.5Fe 0.5SiO 4/C cathode nanocomposite. In: Bulletin of the Korean Chemical Society. 2011 ; Vol. 32, No. 12. pp. 4205-4209.
@article{3f9b92f1a4254998a04b143e800cbdfe,
title = "Structural and electrochemical properties of Li 2Mn 0.5Fe 0.5SiO 4/C cathode nanocomposite",
abstract = "The Li 2Mn 0.5Fe 0.5SiO 4 silicate was prepared by blending of Li 2MnSiO 4 and Li 2FeSiO 4 precursors with same molar ratio. The one of the silicates of Li 2MnSiO 4 is known as high capacitive up to ∼330 mAh/g due to 2 mole electron exchange, and the other of Li 2FeSiO 4 has identical structure with Li 2MnSiO 4 and shows stable cycle with less capacity of ∼170 mAh/g. The major drawback of silicate family is low electronic conductivity (3 orders of magnitude lower than LiFePO 4). To overcome this disadvantage, carbon composite of the silicate compound was prepared by sucrose mixing with silicate precursors and heat-treated in reducing atmosphere. The crystal structure and physical morphology of Li 2Mn 0.5Fe 0.5SiO 4 was investigated by X-ray diffraction, scanning electron microscopy, and high resolution transmission electron microscopy. The Li 2Mn 0.5Fe 0.5SiO 4/C nanocomposite has a maximum discharge capacity of 200 mAh/g, and 63{\%} of its discharge capacity is retained after the tenth cycles. We have realized that more than 1 mole of electrons are exchanged in Li 2Mn 0.5Fe 0.5SiO 4. We have observed that Li 2Mn 0.5Fe 0.5SiO 4 is unstable structure upon first delithiation with structural collapse. High temperature cell performance result shows high capacity of discharge capacity (244 mAh/g) but it had poor capacity retention (50{\%}) due to the accelerated structural degradation and related reaction.",
keywords = "Cathode, Lithium manganese iron silicate, Lithium-ion battery, Physical blending, Polyanion system",
author = "Youngmin Chung and Seung-Ho Yu and Song, {Min Seob} and Kim, {Sung Soo} and Cho, {Won Il}",
year = "2011",
month = "12",
day = "20",
doi = "10.5012/bkcs.2011.32.12.4205",
language = "English",
volume = "32",
pages = "4205--4209",
journal = "Bulletin of the Korean Chemical Society",
issn = "0253-2964",
publisher = "Wiley-Blackwell",
number = "12",

}

TY - JOUR

T1 - Structural and electrochemical properties of Li 2Mn 0.5Fe 0.5SiO 4/C cathode nanocomposite

AU - Chung, Youngmin

AU - Yu, Seung-Ho

AU - Song, Min Seob

AU - Kim, Sung Soo

AU - Cho, Won Il

PY - 2011/12/20

Y1 - 2011/12/20

N2 - The Li 2Mn 0.5Fe 0.5SiO 4 silicate was prepared by blending of Li 2MnSiO 4 and Li 2FeSiO 4 precursors with same molar ratio. The one of the silicates of Li 2MnSiO 4 is known as high capacitive up to ∼330 mAh/g due to 2 mole electron exchange, and the other of Li 2FeSiO 4 has identical structure with Li 2MnSiO 4 and shows stable cycle with less capacity of ∼170 mAh/g. The major drawback of silicate family is low electronic conductivity (3 orders of magnitude lower than LiFePO 4). To overcome this disadvantage, carbon composite of the silicate compound was prepared by sucrose mixing with silicate precursors and heat-treated in reducing atmosphere. The crystal structure and physical morphology of Li 2Mn 0.5Fe 0.5SiO 4 was investigated by X-ray diffraction, scanning electron microscopy, and high resolution transmission electron microscopy. The Li 2Mn 0.5Fe 0.5SiO 4/C nanocomposite has a maximum discharge capacity of 200 mAh/g, and 63% of its discharge capacity is retained after the tenth cycles. We have realized that more than 1 mole of electrons are exchanged in Li 2Mn 0.5Fe 0.5SiO 4. We have observed that Li 2Mn 0.5Fe 0.5SiO 4 is unstable structure upon first delithiation with structural collapse. High temperature cell performance result shows high capacity of discharge capacity (244 mAh/g) but it had poor capacity retention (50%) due to the accelerated structural degradation and related reaction.

AB - The Li 2Mn 0.5Fe 0.5SiO 4 silicate was prepared by blending of Li 2MnSiO 4 and Li 2FeSiO 4 precursors with same molar ratio. The one of the silicates of Li 2MnSiO 4 is known as high capacitive up to ∼330 mAh/g due to 2 mole electron exchange, and the other of Li 2FeSiO 4 has identical structure with Li 2MnSiO 4 and shows stable cycle with less capacity of ∼170 mAh/g. The major drawback of silicate family is low electronic conductivity (3 orders of magnitude lower than LiFePO 4). To overcome this disadvantage, carbon composite of the silicate compound was prepared by sucrose mixing with silicate precursors and heat-treated in reducing atmosphere. The crystal structure and physical morphology of Li 2Mn 0.5Fe 0.5SiO 4 was investigated by X-ray diffraction, scanning electron microscopy, and high resolution transmission electron microscopy. The Li 2Mn 0.5Fe 0.5SiO 4/C nanocomposite has a maximum discharge capacity of 200 mAh/g, and 63% of its discharge capacity is retained after the tenth cycles. We have realized that more than 1 mole of electrons are exchanged in Li 2Mn 0.5Fe 0.5SiO 4. We have observed that Li 2Mn 0.5Fe 0.5SiO 4 is unstable structure upon first delithiation with structural collapse. High temperature cell performance result shows high capacity of discharge capacity (244 mAh/g) but it had poor capacity retention (50%) due to the accelerated structural degradation and related reaction.

KW - Cathode

KW - Lithium manganese iron silicate

KW - Lithium-ion battery

KW - Physical blending

KW - Polyanion system

UR - http://www.scopus.com/inward/record.url?scp=84255184102&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84255184102&partnerID=8YFLogxK

U2 - 10.5012/bkcs.2011.32.12.4205

DO - 10.5012/bkcs.2011.32.12.4205

M3 - Article

VL - 32

SP - 4205

EP - 4209

JO - Bulletin of the Korean Chemical Society

JF - Bulletin of the Korean Chemical Society

SN - 0253-2964

IS - 12

ER -