BROWSE

Related Researcher

Author

Lee, Sang-Young
Energy Soft-Materials Lab (ESML)
Research Interests
  • Soft Materials for Energy Storage/ Conversion Systems

ITEM VIEW & DOWNLOAD

Polarity-tuned Gel Polymer Electrolyte Coating of High-voltage LiCoO2 Cathode Materials

Cited 0 times inthomson ciCited 0 times inthomson ci
Title
Polarity-tuned Gel Polymer Electrolyte Coating of High-voltage LiCoO2 Cathode Materials
Author
Park, Jang-HoonCho, Ju-HyunKim, Jong-SuShim, Eun-GiLee, Yun-SungLee, Sang-Young
Keywords
Lithium-ion batteries; High-voltage lithium cobalt oxide; Polarity; Gel polymer electrolyte coating; Polyimide; Ethylene-vinyl acetate copolymer
Issue Date
2011
Publisher
한국전기화학회
Citation
전기화학회지, v.14, no.2, pp.117 - 124
Abstract
We demonstrate a new surface modification of high-voltage lithium cobalt oxide (tex:\small\textstyle$LiCoO_2$) cathode active materials for lithium-ion batteries. This approach is based on exploitation of a polarity-tuned gel polymer electrolyte (GPE) coating. Herein, two contrast polymers having different polarity are chosen: polyimide (PI) synthesized from thermally curing 4-component (pyromellitic dianhydride/biphenyl dianhydride/phenylenediamine/oxydianiline) polyamic acid (as a polar GPE) and ethylene-vinyl acetate copolymer (EVA) containing 12 wt% vinyl acetate repeating unit (as a less polar GPE). The strong affinity of polyamic acid for tex:\small\textstyle$LiCoO_2$ allows the resulting PI coating layer to present a highly-continuous surface film of nanometer thickness. On the other hand, the less polar EVA coating layer is poorly deposited onto the tex:\small\textstyle$LiCoO_2$, resulting in a locally agglomerated morphology with relatively high thickness. Based on the characterization of GPE coating layers, their structural difference on the electrochemical performance and thermal stability of high-voltage (herein, 4.4 V) tex:\small\textstyle$LiCoO_2$ is thoroughly investigated. In comparison to the EVA coating layer, the PI coating layer is effective in preventing the direct exposure of tex:\small\textstyle$LiCoO_2$ to liquid electrolyte, which thus plays a viable role in improving the high-voltage cell performance and mitigating the interfacial exothermic reaction between the charged tex:\small\textstyle$LiCoO_2$ and liquid electrolytes.
URI
http://scholarworks.unist.ac.kr/handle/201301/6157
DOI
http://dx.doi.org/10.5229/JKES.2011.14.2.117
ISSN
1229-1935
Appears in Collections:
ECHE_Journal Papers

find_unist can give you direct access to the published full text of this article. (UNISTARs only)

Show full item record

qr_code

  • mendeley

    citeulike

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.

MENU