Data on flow cell optimization for membrane-based electrokinetic energy conversion.

Area of Science:

• Electrochemistry
• Materials Science
• Energy Conversion

Background:

• Electrokinetic Energy Conversion (EKEC) offers a method for converting pressure into electrical energy.
• Previous work established a foundational flow cell design for EKEC.
• Optimization is crucial for improving the efficiency and practicality of EKEC devices.

Purpose of the Study:

• To optimize the design of a specialized flow cell for measuring electrokinetic energy conversion (EKEC).
• To investigate and refine key parameters influencing EKEC performance, specifically hydraulic pressure profiles and electrical resistance.
• To identify the optimal electrolyte concentration for enhanced membrane performance within the EKEC system.

Main Methods:

• Utilized four-point Electrochemical Impedance Spectroscopy (EIS) to measure electrical resistance across the flow cell.
• Monitored and adjusted hydraulic pressure profiles generated by recirculating electrolyte solutions.
• Experimentally investigated Nafion 117 membrane properties in LiI/I2 solutions of varying concentrations (0.06–0.96 M).

Main Results:

• Identified optimal flow cell parameters for EKEC measurement.
• Determined the preferred LiI/I2 solution concentration by analyzing membrane properties (solution uptake, internal concentration, ion exchange capacity).
• Calculated transport coefficients and electrokinetic figures of merit using Uniform potential and Space charge models, with a focus on the streaming potential coefficient.

Conclusions:

• The study successfully optimized a flow cell for EKEC measurements.
• Specific LiI/I2 electrolyte concentrations significantly impact membrane properties and overall EKEC performance.
• The findings provide a pathway for enhancing EKEC device efficiency through careful design and material selection.