Article
  • Influence of Heat Treatment on Separators for Lithium Secondary Batteries
  • Lee S, Ryu SW
  • 리튬 이차전지용 분리막에 대한 열처리의 영향
  • 이새미, 류상욱
Abstract
Heat treatment effect of polyethylene (PE) separators was investigated after storage at 80, 100 and 120 ℃ for 1 h. All the samples showed enhanced tensile strength and modulus after heat treatment, but thermal shrinkage up to 15% was observed in PE films having newly formed dimple structure on the surface of fiber after annealed at 100 and 120 ℃. Although there was 5% of thermal shrinkage after annealing at 80 ℃, no such serious changes in PE fiber was observed. Furthermore, the separator was found to have enhanced cell performance with 1.3 and 2.3 times higher tensile strength and modulus after heat treatment at 80 ℃ for 1 h.

본 연구에서는 리튬 이차전지용 분리막을 80, 100, 120 ℃의 온도에서 각각 1시간 동안 열처리하여 형상 및 물성의 변화에 미치는 영향을 평가하였다. 열처리는 전자빔처리에 의한 사슬절단 산화반응과 달리 화학적 반응을 수반하지 않았으며, 흥미롭게도 인장강도 및 탄성계수가 향상되는 효과를 보여주었다. 하지만 100 ℃ 및 120 ℃에서 처리된 분리막의 경우 PE 섬유사에 상당량의 주름이 형성되었으며 각각 7.5 및 15%의 면적수축이 관찰되었다. 결과적으로 80 ℃, 1시간의 처리 조건을 통하여 5%의 면적 수축이 발생되었지만 일반 분리막대비 향상된 전지특성을 유지하면서 최대 1.3배의 인장강도 및 2.3배의 탄성계수를 확보할 수 있었다.

Keywords: separator; heat treatment; tensile strength; discharge capacity; lithium ion battery.

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  • Polymer(Korea) 폴리머
  • Frequency : Bimonthly(odd)
    ISSN 0379-153X(Print)
    ISSN 2234-8077(Online)
    Abbr. Polym. Korea
  • 2023 Impact Factor : 0.4
  • Indexed in SCIE

This Article

  • 2012; 36(1): 93-97

    Published online Jan 25, 2012

  • Received on Aug 26, 2011
  • Accepted on Dec 24, 2011