Optimized Sulfonated Poly(Ether Ether Ketone) Membranes for In-House Produced Small-Sized Vanadium Redox Flow Battery Set-Up
Abstract
:1. Introduction
2. Experimental Details
2.1. Materials
2.2. Preparation of SPEEK Powders
2.3. Preparation of Membranes
2.4. Chemical–Physical Characterization of the Membranes
2.5. Preparation of the Chloride-Based VRFB Electrolyte
2.6. Single-Cell VRFB Tests (Charge/Discharge Measurements and EIS)
2.7. In-House Five-Cell VRFB Stack System
3. Results and Discussion
3.1. Membranes Characterization
3.2. Single-Cell VRFB Tests
3.3. Optimization of Single-Cell VRFB
3.4. Five-Cell VRFB Stack System
4. Conclusions
Supplementary Materials
Author Contributions
Funding
Data Availability Statement
Acknowledgments
Conflicts of Interest
References
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Membrane | (cm2·s−1) | (106 S·s·cm−3) | σ (S·cm−1) | σafterVuptake (S·cm−1) | σloss (%) |
---|---|---|---|---|---|
Nafion 115 | 1.52 10−8 | 5.9 | 9.00·10−2 | 5.52·10−2 | 38 |
SPEEK50-0 | 3.23 10−10 | 49.2 | 1.59·10−2 | 1.39·10−2 | 13 |
SPEEK50-10 | 3.55 10−10 | 17.2 | 1.59·10−2 | 6.12·10−3 | 62 |
SPEEK50-20 | 1.22 10−9 | 15.9 | 2.60·10−2 | 1.94·10−2 | 25 |
SPEEK64-0 | 8.60 10−10 | 25.3 | 2.18·10−2 | 9.25·10−3 | 58 |
SPEEK64-10 | 2.60 10−9 | 18.8 | 4.90·10−2 | 3.46·10−2 | 29 |
SPEEK64-20 | 9.09 10−10 | 27.5 | 2.00·10−2 | 1.60·10−2 | 20 |
Membrane | Cycle Time (h) | Mean Charge Voltage (V) | Mean Discharge Voltage (V) | Coulombic Efficiency (%) |
---|---|---|---|---|
Nafion 115 | 9.35 | 1.53 | 1.12 | 85.5 |
SPEEK50-0 | 15.32 | 1.64 | 0.93 | 96.1 |
SPEEK64-20 | 14.79 | 1.58 | 1.02 | 97.1 |
Configuration | Rs (mΩ) | Rct (mΩ) | CPE (mF) | W (S s0.5) | Rtot (mΩ) |
---|---|---|---|---|---|
STD-Nafion115 | 261 | 425 | 8.5 | 36.5 | 686 |
STD-SPEEK50-0 | 987 | 147 | 7.0 | 136 | 1134 |
OPT-Nafion115 | 193 | 195 | 9.8 | 66.7 | 388 |
OPT-SPEEK50-0 | 184 | 136 | 11.5 | 210 | 320 |
Operating Parameter | Details |
---|---|
Electrolyte temperature | 25 ± 2 °C |
Optimized composition of the electrolyte | [V3+] = 1.25 M, [VO2+] = 1.25 M [SO42−] = 2.50 M [Cl−] = 6.00 M |
Anode face velocity | 1.5 cm·s−1 |
Cathode face velocity | 1.5 cm·s−1 |
Charge method | Constant current |
Charge current density (cycle 1) | 20 mA·cm−2 |
Charge current density (cycle > 1) | 20–60 mA·cm−2 |
Top-of-charge cut-off voltage (per cell) | 1.7–2.0 V |
Discharge method | Constant current |
Discharge current density (cycle 1) | 20–100 mA·cm−2 |
Discharge current density (cycle > 1) | 20–100 mA·cm−2 |
Bottom-of-discharge cut-off voltage (per cell) | 0.7 V |
Carbon felt | GFD SGL 4.6 |
Compression rate | 0.2 |
Electrode area | 459 cm2 (17 cm × 27 cm) |
Bipolar Plate | PPG86 SGL |
Membrane | Optimized SPEEK |
Cycle | Current Density (mA/cm2) | Current (A) | Electrolyte Volume (L) | Discharge Capacity (Ah/L) | Coulombic Efficiency (%) | Mean Charge Voltage (V) | Mean Discharge Voltage (V) |
---|---|---|---|---|---|---|---|
1 * | 20 | 9.2 | 3 | - | - | 8.7 | 3.9 |
2 | 20 | 9.2 | 3 | 6.7 | 94.5 | 8.6 | 3.9 |
3 | 50 | 23.0 | 3 | 7.1 | 87.1 | 8.8 | 3.8 |
4 | 50 | 23.0 | 5 | 6.2 | 87.3 | 8.8 | 3.8 |
5 | 80 | 36.7 | 5 | 5.5 | 79.5 | 8.9 | 3.6 |
6 | 100 | 44.3 | 5 | 4.9 | 74.0 | 9.6 | 3.4 |
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Rizzuti, A.; Dilonardo, E.; Cozzolino, G.; Matera, F.; Carbone, A.; Musio, B.; Mastrorilli, P. Optimized Sulfonated Poly(Ether Ether Ketone) Membranes for In-House Produced Small-Sized Vanadium Redox Flow Battery Set-Up. Membranes 2024, 14, 176. https://doi.org/10.3390/membranes14080176
Rizzuti A, Dilonardo E, Cozzolino G, Matera F, Carbone A, Musio B, Mastrorilli P. Optimized Sulfonated Poly(Ether Ether Ketone) Membranes for In-House Produced Small-Sized Vanadium Redox Flow Battery Set-Up. Membranes. 2024; 14(8):176. https://doi.org/10.3390/membranes14080176
Chicago/Turabian StyleRizzuti, Antonino, Elena Dilonardo, Gennaro Cozzolino, Fabio Matera, Alessandra Carbone, Biagia Musio, and Piero Mastrorilli. 2024. "Optimized Sulfonated Poly(Ether Ether Ketone) Membranes for In-House Produced Small-Sized Vanadium Redox Flow Battery Set-Up" Membranes 14, no. 8: 176. https://doi.org/10.3390/membranes14080176