Speaker
Description
Hydrogen production via alkaline water electrolysis (AWE) is an important clean energy technology; however, its efficiency is challenged by poor gas-liquid transport, high ohmic losses, and material degradation. Additive manufacturing (AM), specifically laser powder bed fusion (LPBF), enables the fabrication of porous transport layers (PTLs) with precise control over porosity and feature resolution, thereby improving gas transport and overall system performance.
This research focuses on optimizing porous transport layer (PTL) structures by refining printing parameters for Inconel 718 and implementing intricate lattice designs. A diamond lattice with a unit cell size of 2x2x2 mm³ and wall thicknesses ranging from 0.1 mm to 0.5 mm is designed to investigate the ideal structure for improving bubble transport. Aside from lattice structures designed to enhance bubble removal, process-driven stochastic pores can further optimize gas-liquid interactions and increase the number of electrochemical sites by increasing the overall effective surface area. These stochastic pores are generated by adjusting hatch spacing (100-500 μm) and rotational angles (67, 60, and 90°) to create lack-of-fusion pores across the electrode. An investigation into optimal process parameter selection is conducted to achieve repeatable, high-resolution geometric fidelity across various pore structures, using advanced characterization techniques, such as X-ray computed tomography (XCT), to analyze porosity distribution and structural properties.
The combination of lattice geometries and process-driven porosity yields porosity ranges of 40-80%, hydraulic pore sizes of 0.1-0.9 mm, and tortuosity values of 1-4. These properties are expected to enhance mass-transport efficiency in anion-exchange water electrolysis (AWE) systems by enabling a diverse array of pore types, sizes, and shapes within the PTL structure. The performance of the pore network is evaluated through electrochemical testing, which includes linear sweep voltammetry, whereby at 1V, the achieved current ranged from 120 to 250 mA, while the double-layer capacitance varied from 500 to 1000 µF/cm². The resulting electrochemical performance validates the design's efficacy.
By refining design and manufacturing parameters, in tandem with electrochemical testing, this research will establish a repeatable method for producing high-resolution lattice structures with controlled porosity. The findings will inform manufacturing protocols and design guidelines that can be integrated into existing AWE systems, leading to improvements in efficiency, geometric precision, and gas transport performance in additively manufactured PTLs, thereby supporting the enhancement of clean hydrogen production technologies.
| Country | Canada |
|---|---|
| Student Awards | I would like to submit this presentation into both awards |
| Acceptance of the Terms & Conditions | Click here to agree |
