Properties of a novel hard-carbon optimized to large size Li ion secondary battery studied by 7Li NMR

Kazuma Gotoh, Mariko Maeda, Aisaku Nagai, Atsushi Goto, Masataka Tansho, Kenjiro Hashi, Tadashi Shimizu, Hiroyuki Ishida

Research output: Contribution to journalArticle

55 Citations (Scopus)

Abstract

The state of lithium in a novel hard-carbon optimized to the anode of large size Li ion secondary battery, which has been recently commercialized, was investigated and compared with other existing hard-carbon samples by 7Li NMR method. The new carbon material showed a peak at 85 ppm with a shoulder signal at 7 ppm at room temperature in static NMR spectrum, and the former shifted to 210 ppm at 180 K. The latter at room temperature was attributed to Li doped in small particles contained in the sample. The new carbon sample showed weaker intensity of cluster-lithium signal than the other hard-carbon samples in NMR, which corresponded to a tendency of less "constant voltage" (CV) capacity in charge-discharge curves of electrochemical evaluation. Smaller CV capacity and initial irreversible capacity, which are the features of the novel hard-carbon, are considered to correspond to a blockade of the diffusion of Li into pore of carbon.

Original languageEnglish
Pages (from-to)1322-1328
Number of pages7
JournalJournal of Power Sources
Volume162
Issue number2 SPEC. ISS.
DOIs
Publication statusPublished - Nov 22 2006

Fingerprint

storage batteries
Secondary batteries
Carbon
Nuclear magnetic resonance
Ions
nuclear magnetic resonance
carbon
ions
Lithium
lithium
Electric potential
electric potential
room temperature
shoulders
Anodes
tendencies
anodes
porosity
Temperature
evaluation

Keywords

  • Li NMR
  • Anode
  • Battery
  • Electric vehicle
  • Hard-carbon
  • Lithium

ASJC Scopus subject areas

  • Electrochemistry
  • Fuel Technology
  • Materials Chemistry
  • Energy (miscellaneous)

Cite this

Properties of a novel hard-carbon optimized to large size Li ion secondary battery studied by 7Li NMR. / Gotoh, Kazuma; Maeda, Mariko; Nagai, Aisaku; Goto, Atsushi; Tansho, Masataka; Hashi, Kenjiro; Shimizu, Tadashi; Ishida, Hiroyuki.

In: Journal of Power Sources, Vol. 162, No. 2 SPEC. ISS., 22.11.2006, p. 1322-1328.

Research output: Contribution to journalArticle

Gotoh, Kazuma ; Maeda, Mariko ; Nagai, Aisaku ; Goto, Atsushi ; Tansho, Masataka ; Hashi, Kenjiro ; Shimizu, Tadashi ; Ishida, Hiroyuki. / Properties of a novel hard-carbon optimized to large size Li ion secondary battery studied by 7Li NMR. In: Journal of Power Sources. 2006 ; Vol. 162, No. 2 SPEC. ISS. pp. 1322-1328.
@article{3ebcea6879a744e5b695521138ae81f5,
title = "Properties of a novel hard-carbon optimized to large size Li ion secondary battery studied by 7Li NMR",
abstract = "The state of lithium in a novel hard-carbon optimized to the anode of large size Li ion secondary battery, which has been recently commercialized, was investigated and compared with other existing hard-carbon samples by 7Li NMR method. The new carbon material showed a peak at 85 ppm with a shoulder signal at 7 ppm at room temperature in static NMR spectrum, and the former shifted to 210 ppm at 180 K. The latter at room temperature was attributed to Li doped in small particles contained in the sample. The new carbon sample showed weaker intensity of cluster-lithium signal than the other hard-carbon samples in NMR, which corresponded to a tendency of less {"}constant voltage{"} (CV) capacity in charge-discharge curves of electrochemical evaluation. Smaller CV capacity and initial irreversible capacity, which are the features of the novel hard-carbon, are considered to correspond to a blockade of the diffusion of Li into pore of carbon.",
keywords = "Li NMR, Anode, Battery, Electric vehicle, Hard-carbon, Lithium",
author = "Kazuma Gotoh and Mariko Maeda and Aisaku Nagai and Atsushi Goto and Masataka Tansho and Kenjiro Hashi and Tadashi Shimizu and Hiroyuki Ishida",
year = "2006",
month = "11",
day = "22",
doi = "10.1016/j.jpowsour.2006.09.001",
language = "English",
volume = "162",
pages = "1322--1328",
journal = "Journal of Power Sources",
issn = "0378-7753",
publisher = "Elsevier",
number = "2 SPEC. ISS.",

}

TY - JOUR

T1 - Properties of a novel hard-carbon optimized to large size Li ion secondary battery studied by 7Li NMR

AU - Gotoh, Kazuma

AU - Maeda, Mariko

AU - Nagai, Aisaku

AU - Goto, Atsushi

AU - Tansho, Masataka

AU - Hashi, Kenjiro

AU - Shimizu, Tadashi

AU - Ishida, Hiroyuki

PY - 2006/11/22

Y1 - 2006/11/22

N2 - The state of lithium in a novel hard-carbon optimized to the anode of large size Li ion secondary battery, which has been recently commercialized, was investigated and compared with other existing hard-carbon samples by 7Li NMR method. The new carbon material showed a peak at 85 ppm with a shoulder signal at 7 ppm at room temperature in static NMR spectrum, and the former shifted to 210 ppm at 180 K. The latter at room temperature was attributed to Li doped in small particles contained in the sample. The new carbon sample showed weaker intensity of cluster-lithium signal than the other hard-carbon samples in NMR, which corresponded to a tendency of less "constant voltage" (CV) capacity in charge-discharge curves of electrochemical evaluation. Smaller CV capacity and initial irreversible capacity, which are the features of the novel hard-carbon, are considered to correspond to a blockade of the diffusion of Li into pore of carbon.

AB - The state of lithium in a novel hard-carbon optimized to the anode of large size Li ion secondary battery, which has been recently commercialized, was investigated and compared with other existing hard-carbon samples by 7Li NMR method. The new carbon material showed a peak at 85 ppm with a shoulder signal at 7 ppm at room temperature in static NMR spectrum, and the former shifted to 210 ppm at 180 K. The latter at room temperature was attributed to Li doped in small particles contained in the sample. The new carbon sample showed weaker intensity of cluster-lithium signal than the other hard-carbon samples in NMR, which corresponded to a tendency of less "constant voltage" (CV) capacity in charge-discharge curves of electrochemical evaluation. Smaller CV capacity and initial irreversible capacity, which are the features of the novel hard-carbon, are considered to correspond to a blockade of the diffusion of Li into pore of carbon.

KW - Li NMR

KW - Anode

KW - Battery

KW - Electric vehicle

KW - Hard-carbon

KW - Lithium

UR - http://www.scopus.com/inward/record.url?scp=33750955403&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=33750955403&partnerID=8YFLogxK

U2 - 10.1016/j.jpowsour.2006.09.001

DO - 10.1016/j.jpowsour.2006.09.001

M3 - Article

AN - SCOPUS:33750955403

VL - 162

SP - 1322

EP - 1328

JO - Journal of Power Sources

JF - Journal of Power Sources

SN - 0378-7753

IS - 2 SPEC. ISS.

ER -