Polydopamine hydrophilic modification of polypropylene separator for lithium ion battery

• Published in: Journal of applied polymer science Vol. 131; no. 15; pp. np - n/a
• Main Authors: Wang, Dan, Zhao, Zhongling, Yu, Lina, Zhang, Kejin, Na, Hui, Ying, Shanqiang, Xu, Dechao, Zhang, Guo
• Format: Journal Article
• Language: English
• Published: Hoboken, NJ Blackwell Publishing Ltd 05.08.2014; Wiley; Wiley Subscription Services, Inc
• Subjects: Applied sciences; batteries and fuel cells; Certification testing; coatings; Contact angle; Direct energy conversion and energy accumulation; Discharge; Electrical engineering. Electrical power engineering; Electrical power engineering; Electrochemical conversion: primary and secondary batteries, fuel cells; Exact sciences and technology; Forms of application and semi-finished materials; hydrophilic polymers; Liquids; Lithium-ion batteries; Materials science; Miscellaneous; nanostructured polymers; Polymer industry, paints, wood; Polymers; Polypropylenes; porous materials; Separators; Technology of polymers; Tensile strength; Wettability; nanostructured polymers; batteries and fuel cells; Polymer solid electrolyte; Wettability; Surface properties; Olefin polymer; porous materials; Lithium Hexafluophosphates; Dopamine; Coating material; Electrical properties; Propylene polymer; Ionic conductivity; Mechanical properties; Secondary cell; Experimental study; Tensile strength; Surface treatment; Lithium battery; hydrophilic polymers; Electrochemical properties; coatings; Morphology; Oxidative polymerization; Separator
• ISSN: 0021-8995; 1097-4628
• DOI: 10.1002/app.40543

ABSTRACT The modified polypropylene (PP) separators with self‐polymerization of dopamine on the surfaces are prepared by a simple solution‐immersion method to improve the interfacial hydrophilic and discharge performance. The contact angle test and the liquid electrolyte uptake capacity test results show that the wettability and the electrolyte‐retention ability of polydopamine‐modified separator are improved significantly. The robust and thin polydopamine layer on the surface also enhances thermal performance and tensile strength of the modified PP separator certified by DSC and tensile strength tests. The ionic conductivity of the modified PP separator is up to 3.08 mS·cm−1, ∼2.5 times of the bare separator. Good discharge capacity retention and C‐rate discharge performance are demonstrated by a 2025 coin half‐cell with the liquid electrolyte‐soaked polydopamine modified PP separator sandwiched between lithium metal anode and LiFePO4 cathode. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40543.