Article
  • Fabrication of Porous EVOH Separator Membrane Using NIPS Process for Next-Generation Lithium-ion Battery

  • Su-Jong Bae*,#, Myoungsoo Shin****,#, Seungmin Yoo*****,† , and Woo-Jin Song*, **, ***,†

  • *Department of Polymer Science and Engineering, Chungnam National University, Daejeon 34134, Korea
    **Department of Organic Materials Engineering, Chungnam National University, Daejeon 34134, Korea
    ***Department of Chemical Engineering and Applied Chemistry, Chungnam National University, Daejeon 34134, Korea
    ****Anode Material R&D Group, POSCO Future M Co., Ltd, Sejong, Korea
    *****Department of Chemical Engineering, Ulsan College, Ulsan 44022, Korea

  • NIPS를 이용한 차세대 리튬이온전지용 다공성 EVOH 분리막의 제조

  • 배수종*,# · 신명수****,# · 유승민*****,† · 송우진*, **, ***,†

  • *충남대학교 고분자공학과, **충남대학교 유기재료공학과, ***충남대학교 응용화학공학과 ****포스코퓨처엠, *****울산과학대학교 화학공학과

  • Reproduction, stored in a retrieval system, or transmitted in any form of any part of this publication is permitted only by written permission from the Polymer Society of Korea.

Abstract

Lithium-ion batteries have safety problems such as explosion and fire due to the low thermal stability of the polyolefin-based separator. In this study, a separator was fabricated using a nonsolvent-induced phase separation (NIPS) method of ethylene-vinyl alcohol (EVOH) polymer surface-modified with (3-Glycidyloxypropyl)trimethoxysilane (GPTMS), and the electrochemical performance was evaluated. When producing the EVOH separator film, the surface was modified with GPTMS to have improved physical properties, and a GPTMS-treated EVOH (G-EVOH) separator having a uniform pore size was produced by selecting a solvent and a non-solvent. It was confirmed that this separator has improved electrolyte wettability and thermal stability (at 140 ℃) compared to polypropylene (PP) separators. Full-cell was fabricated with a configuration of LiCoO2|Graphite electrode and G-EVOH, and as a result of evaluating the life characteristics at 2C, the capacity retention rate after 90 cycles was improved by 75% compared to PP.


리튬이온전지는 폴리올레핀계 분리막의 낮은 열안정성으로 인해 폭발, 화재 등의 안전성 문제를 가지고 있다. 본 연구에서는 (3-glycidyloxypropyl)trimethoxysilane(GPTMS)로 표면개질한 ethylene-vinyl alcohol(EVOH)고분자를 nonsolvent-induced phase separation(NIPS)방법을 이용해 분리막을 제작하였으며, 리튬이온전지 내에서 분리막의 전기화학적 성능을 평가하였다. EVOH 분리막 필름 제작 시 GPTMS로 표면 개질함으로써 향상된 물성을 가질 수 있도록 하였으며, 용매 및 비용매의 선별을 통해 균일한 기공 크기를 갖는 (GPTMS-treated EVOH) (G-EVOH) 분리막을 제작했다. 이 분리막은 polypropylene(PP) 분리막 대비 향상된 전해질 젖음성과 열안정성(at 140 ℃)을 가지는 것을 확인하였다. LiCoO2|Graphite 전극 구성과 G-EVOH분리막의 조합으로 완전셀을 제작하였으며, 2C에서 수명 특성 평가를 진행한 결과 90싸이클 이후 용량유지율이 PP대비 75% 향상되었다.


Keywords: separator membrane, nonsolvent-induced phase separation, lithium-ion battery, porous film.

  • 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

  • 2023; 47(5): 628-633

    Published online Sep 25, 2023

  • 10.7317/pk.2023.47.5.628
  • Received on May 15, 2023
  • Revised on Jun 5, 2023
  • Accepted on Jun 7, 2023

Correspondence to

  • Seungmin Yoo*****, Woo-Jin Song*, **, ***

  • *Department of Polymer Science and Engineering, Chungnam National University, Daejeon 34134, Korea
    **Department of Organic Materials Engineering, Chungnam National University, Daejeon 34134, Korea
    ***Department of Chemical Engineering and Applied Chemistry, Chungnam National University, Daejeon 34134, Korea
    *****Department of Chemical Engineering, Ulsan College, Ulsan 44022, Korea

  • E-mail: smyoo@uc.ac.kr, wjsong@cnu.ac.kr