Difference between approximate and rigorously measured transference numbers in fluorinated electrolytes

Hydrogen-ion transport numbers, water transference numbers, and acid absorption are reported for some cation-exchange membranes in presence of 0.1N, 1.0N, and 5.0N sulphuric acid. The transport numbers of hydrogen ion remain fairly close to unity even at the highest acid concentration; this is largely due to the retardation of the anions by the electro-osmotic water flux. With increasing acid concentration the water transference number falls to a lower limit of 1.0 mole per faraday; with the driest membrane used this value is obtained at all acid concentrations used. This behaviour suggests that when there are less than about 11 moles of water available per hydrogen ion in the membrane, association occurs between sulphonate groups and hydrogen ions, with consequent immobilization of the latter.

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A Numerical Framework for Concentrated-Solution Theory

ECS Meeting Abstracts ◽

10.1149/ma2020-024786mtgabs ◽

2020 ◽

Vol MA2020-02 (4) ◽

pp. 786-786

Author(s):

Alexander John Van-Brunt ◽

Patrick E. Farrell ◽

Charles W. Monroe

Keyword(s):

Solution Theory ◽

Concentrated Solution

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How efficient is Li+ ion transport in solvate ionic liquids under anion-blocking conditions in a battery?

Physical Chemistry Chemical Physics ◽

10.1039/c8cp06214e ◽

2018 ◽

Vol 20 (46) ◽

pp. 29174-29183 ◽

Cited By ~ 27

Author(s):

Dengpan Dong ◽

Fabian Sälzer ◽

Bernhard Roling ◽

Dmitry Bedrov

Keyword(s):

Ionic Liquids ◽

Ion Transport ◽

Transference Numbers ◽

Li Ion ◽

Correlated Motion

Anti-correlated motion of cations and anions leads to very low Li+ transference numbers in solvate ionic liquids.

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Development of Polymer Blend Electrolyte Membranes Based on Chitosan: Dextran with High Ion Transport Properties for EDLC Application

International Journal of Molecular Sciences ◽

10.3390/ijms20133369 ◽

2019 ◽

Vol 20 (13) ◽

pp. 3369 ◽

Cited By ~ 36

Author(s):

Shujahadeen B. Aziz ◽

Muhamad H. Hamsan ◽

Mohd F. Z. Kadir ◽

Wrya O. Karim ◽

Ranjdar M. Abdullah

Keyword(s):

Ion Transport ◽

Polymer Blend ◽

Lithium Perchlorate ◽

Linear Sweep Voltammetry ◽

Solid Polymer ◽

Transference Numbers ◽

Equivalent Series Resistance ◽

Electrolyte Membranes ◽

Ion Conducting ◽

Polymer Blend Electrolyte

Solid polymer blend electrolyte membranes (SPBEM) composed of chitosan and dextran with the incorporation of various amounts of lithium perchlorate (LiClO4) were synthesized. The complexation of the polymer blend electrolytes with the salt was examined using FTIR spectroscopy and X-ray diffraction (XRD). The morphology of the SPBEs was also investigated using field emission scanning electron microscopy (FESEM). The ion transport behavior of the membrane films was measured using impedance spectroscopy. The membrane with highest LiClO4 content was found to exhibit the highest conductivity of 5.16 × 10−3 S/cm. Ionic (ti) and electronic (te) transference numbers for the highest conducting electrolyte were found to be 0.98 and 0.02, respectively. Electrochemical stability was estimated from linear sweep voltammetry and found to be up to ~2.3V for the Li+ ion conducting electrolyte. The only existence of electrical double charging at the surface of electrodes was evidenced from the absence of peaks in cyclic voltammetry (CV) plot. The discharge slope was observed to be almost linear, confirming the capacitive behavior of the EDLC. The performance of synthesized EDLC was studied using CV and charge–discharge techniques. The highest specific capacitance was achieved to be 8.7 F·g−1 at 20th cycle. The efficiency (η) was observed to be at 92.8% and remained constant at 92.0% up to 100 cycles. The EDLC was considered to have a reasonable electrode-electrolyte contact, in which η exceeds 90.0%. It was determined that equivalent series resistance (Resr) is quite low and varies from 150 to 180 Ω over the 100 cycles. Energy density (Ed) was found to be 1.21 Wh·kg−1 at the 1st cycle and then remained stable at 0.86 Wh·kg−1 up to 100 cycles. The interesting observation is that the value of Pd increases back to 685 W·kg−1 up to 80 cycles.

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Numerical Analysis of Vanadium Ion Crossover Phenomena in All-Vanadium Redox Flow Batteries Based on the Concentrated Solution Theory

ECS Meeting Abstracts ◽

10.1149/ma2016-02/53/4077 ◽

2016 ◽

Keyword(s):

Numerical Analysis ◽

Solution Theory ◽

Redox Flow Batteries ◽

Flow Batteries ◽

Concentrated Solution ◽

Vanadium Redox ◽

Vanadium Ion

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Mechanism of ion transport in perfluoropolyether electrolytes with a lithium salt

Soft Matter ◽

10.1039/c7sm00794a ◽

2017 ◽

Vol 13 (32) ◽

pp. 5389-5396 ◽

Cited By ~ 9

Author(s):

Ksenia Timachova ◽

Mahati Chintapalli ◽

Kevin R. Olson ◽

Sue J. Mecham ◽

Joseph M. DeSimone ◽

...

Keyword(s):

Ion Transport ◽

Polymer Electrolytes ◽

Lithium Salt ◽

Transference Numbers ◽

Lithium Salts ◽

Fluorinated Carbon

Perfluoropolyethers (PFPEs) are polymer electrolytes with fluorinated carbon backbones that have high flash points and have been shown to exhibit moderate conductivities and high cation transference numbers when mixed with lithium salts.

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