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Abstract Developing promising solid‐state Li batteries with capabilities of high current densities have been a major challenge partly due to large interfacial resistance across the electrode/electrolyte interfaces. This work represents an integrated network of self‐standing polymer electrolyte and active electrode materials with in situ UV cross‐linking. This method provides a uniform morphology of composite polymer electrolyte with low thickness of 20–40 μm. This modification leads to promising cycling results with 85% specific capacity retention in Li||LiFePO4cell over 100 cycles at high current densities of 170 mA g−1(~25 μA cm−2, 1 C).By applying this method, the interfacial resistance decreases as high as seven folds compared to noncross‐linked interfaces. The following work introduce a facile and cost‐effective method in developing fast‐charging self‐standing polymer batteries with enhanced electrochemical properties. image
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Surface‐engineered Nafion/ CNTs nanocomposite membrane with improved voltage efficiency for vanadium redox flow battery
Abstract A carbon nanotubes (CNTs) reinforced Nafion membrane (CNT/N) with reduced interfacial resistance was prepared and served as a promising ion exchange membrane for vanadium redox flow batteries (VRFBs). The reinforcement of CNT effectively enhanced the tensile properties of Nafion membranes. The electrochemical properties of CNT/N membrane were analyzed by electrochemical impedance spectroscopy (EIS) and fitted with an analytical model to investigate the ionic and interfacial resistances. The EIS measurement reveals that the exposed CNT on the composite membrane surface significantly reduced the interfacial resistance of the membrane. The VRFB single cell performance of the CNT/N shows higher voltage efficiency (93% vs 89%) and energy efficiency (86% vs 83%) than recast Nafion at a current density of 40 mA cm−2. The cycling stability measurement showed that the discharge capacity retention of the VRFB cell equipped with CNT/N was greatly enhanced. The results suggest that the incorporation of CNT in ion exchange membrane is an effective approach for achieving lower membrane bulky and interfacial resistance, and thus, improving capacity retention, voltage, and energy efficiency.
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- Award ID(s):
- 1706910
- PAR ID:
- 10360084
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Journal of Applied Polymer Science
- Volume:
- 139
- Issue:
- 7
- ISSN:
- 0021-8995
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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