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Abstract This work investigates the application of poly(3,4‐ethylenedioxythiophene) polystyrenesulfonate (PEDOT:PSS) with polyethylene oxide (PEO) in lithium batteries (LIBs). This composite film comprising PEDOT:PSS and PEO was 3D printed onto a carbon nanofiber (CNF) substrate to serve as a layer between the polypropylene (PP) separator and the lithium anode in LIBs. The resulting CNF‐PEDOT:PSS‐PEO film exhibited superior mechanical and thermal properties compared to conventional PP separators. Mechanical tests revealed a high Young's modulus and puncture strength for the composite film. Thermal stability tests indicated that the CNF‐PEDOT:PSS‐PEO film remained stable at higher temperatures compared to the commercial PP separator, and combustion tests confirmed its superior fire‐resistance properties. In terms of conductivity, the composite film maintained comparable ionic conductivity to the commercial PP separator. Electrochemical tests demonstrated that LIBs incorporating the CNF‐PEDOT:PSS‐PEO film exhibited slight improvement in cycling performance, with a 7.9 % increase in long‐term cycling capacity compared to LIBs using only the commercial PP separator. These findings indicate that the developed CNF‐PEDOT:PSS‐PEO composite film holds promise to improve safety, while maintaining the electrochemical performance of LIBs by reducing dendrite formation and enhancing thermal stability.
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This content will become publicly available on November 1, 2025
Cathodically deposited ZIF-8 compact layer on an 8-µm ultrathin polypropylene separator to enhance the performance of lithium-sulfur and lithium-metal batteries
The development of high-performance battery technologies necessitates ultrathin separators with superior mechanical strength and electrochemical properties. We present an innovative 1 µm thick, pinhole-free zeolitic imidazolate framework-8 (ZIF-8) layer, cathodically deposited on an 8 µm thick commercial polypropylene (PP) film in a rapid process, resulting in a ZIF-8@8-µm PP flexible membrane. This crack-free ZIF-8 layer, featuring angstrom-scale pores and chemical polar groups, functions as a Li+ sieve, regulating Li+ transport, controlling Li deposition, and blocking dissolved active cathode materials. It also enhances Li+ diffusion and transference number, extending the Sand’s time for Li dendrite formation. Consequently, the ZIF-8@8-µm PP separator addresses polysulfide shuttling in Li-S batteries and Li dendrite formation in Li-metal batteries, significantly improving their performance compared to conventional separators. Our findings indicate that while the 8-μm PP alone is unsuitable as a battery separator, the ZIF-8@8-μm PP, possesses the mechanical strength and electrochemical properties necessary for developing both Li-S and Li-metal batteries, as well as application in conventional Li-ion batteries with enhanced volumetric energy densities.
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- PAR ID:
- 10553414
- Publisher / Repository:
- Elsevier, ScienceDirect
- Date Published:
- Journal Name:
- Chemical Engineering Journal
- Volume:
- 500
- Issue:
- C
- ISSN:
- 1385-8947
- Page Range / eLocation ID:
- 157192
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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