Low Cost Bipolar Plates for Large Scale PEM Electrolyzers

Abstract

PEM electrolysis is a promising technology for large scale storage of surplus electricity, though it is still costly mainly due to the manufacture of large area and high purity Ti bipolar plates (BPP). In this work we have developed an Au/Ti coating deposited by electrodeposition/thermal spraying on stainless steel BPP. The coating was physically characterized with SEM and electrochemically evaluated in simulated anode conditions. Interfacial contact resistance (ICR) vs. compaction pressure measurements showed that the coating is highly conductive. It successfully protected the stainless steel substrate from corrosion. However, the Au modification detached after 6 h of application of a potential of 2 V vs. RHE. Consequently the Au modification has to be replaced by either another precious metal or a corrosion resistant electroceramic. The coating reported herein could have a large impact on the cost of PEM electrolyzers for large scale electricity storage from renewables.

Comprehensive investigation of novel pore-graded gas diffusion layers for high-performance and cost-effective proton exchange membrane electrolyzers

“…The cost of thermal spraying of GDLs to reach the benchmark in terms of performance and cost for large-scale m 2 -size production has been estimated as 20-100 USD m À2 . 25 Overall, the results suggest the possibility of using thermal spraying for manufacturing the entire stack interconnector on a stainless steel BPP, including for the protective Ti coating, 18,24,25,29 to the large/medium pore-size GDLs (this work) and backing layer. 32 All of them could be produced in one manufacturing step, representing a significant cost reduction for the interconnectors, which account for almost 70% of the total stack value.…”

“…2 This task usually requires a complex flow field geometry, which increases the manufacturing cost of the titanium BPPs. 17,18 The BPPs are often combined with very thin GDLs to maintain a uniform electrical connection with the electrode. 19 The second cell design focuses on the GDL, while the BPP is simply regarded as a separator and can be a flat metal sheet without a flow field.…”

Durable Membrane Electrode Assemblies for Proton Exchange Membrane Electrolyzer Systems Operating at High Current Densities

“…For example, BPPs are manufactured on titanium thanks to its corrosion stability in oxidative environments, but machining this metal is complicate and expensive [16,17]. Recently, coated stainless steel has proven to be an alternative base material for BPPs, showing similar durability than the titanium ones [18,19].…”

A Thin Layer of Activated Carbon Deposited on Polyurethane Cube Leads to New Conductive Bioanode for (Plant) Microbial Fuel Cell

“…Thus, the studied resistances were the anolyte resistance (R S ), the biofilm resistance (R BIO ), the contact resistance between PU/AC electrodes and titanium current collectors (R CR ) and the resistance of electrodes without biofilm (R PU/AC ). Moreover, it was assumed that the R CR was equal to 1 Ω as earlier indicated by Gago et al [57] and that the R S was the inverse of the anolyte conductivity multiplied by the distance between current collectors. For the R PU/AC , it was the initial ohmic resistance that was deducted from the measured in situ R ohmic bioanode before inoculation of anolytes.…”