Smoltek’s low-iridium PTE reach target of 0.1 mg iridium/​cm2

Smol­tek has developed a por­ous trans­port elec­trode (PTE) that reduces the amount of iridi­um cata­lysts in PEM elec­tro­lyz­ers to a min­im­al 0.1 mg/​cm², thus reach­ing the level that is con­sidered to make large-scale pro­duc­tion of PEM elec­tro­lyz­ers profitable.

0.1 mg iridi­um per square cen­ti­meter – a tech­no­lo­gic­al breakthrough

We are the only ones to pro­duce hydro­gen with only 0.1 mg iridium/​cm² without com­prom­ising cell per­form­ance. We have thus solved one of the hydro­gen industry’s biggest tech­nic­al chal­lenges – the lim­ited avail­ab­il­ity of iridi­um, which has so far been an obstacle to large-scale pro­duc­tion of PEM electrolyzers.

^{Ellinor Ehrn­berg, Pres­id­ent of Smol­tek Hydrogen}

In addi­tion to the lim­ited avail­ab­il­ity of the scarce pre­cious met­al (glob­al sup­ply only 9 tons/​year), the high costs of iridi­um have also been a source of lim­ited invest­ment will­ing­ness for PEM electrolyzers.

250-hour dur­ab­il­ity shows same res­ult as 1,000-hour test 2024
In a recent dur­ab­il­ity test over 250 hours of con­tinu­ous oper­a­tion (at 2 A/​cm²), Smol­tek Hydrogen’s PTE pro­duced hydro­gen with a cata­lyst load­ing of only 0.1 mg iridium/​cm² – without any degrad­a­tion of the nano­struc­ture of the elec­tro­lyz­er cell. The test res­ults demon­strate that the company’s anode elec­trode tech­no­logy is dur­able and effi­cient, while redu­cing iridi­um usage by 95 per­cent com­pared to con­ven­tion­al technology.

This test showed the same res­ults as the 1,000-hour dur­ab­il­ity test we car­ried out in April 2024, but now with half the amount of iridi­um. When we saw that the cell per­form­ance was equi­val­ent at both 0.1 mg and 0.2 mg iridi­um, we chose to dis­con­tin­ue the test and focus devel­op­ment on oth­er parts of the PTE tech­no­logy for the next longer dur­ab­il­ity test.

^{Fabi­an Wenger, Head of R&D at Smol­tek Hydrogen}

Smoltek’s PTE is mak­ing a mark in the hydro­gen industry
Smol­tek Hydrogen’s nano­struc­ture for PTE has been developed in record time. The first pro­to­types with 0.5 mg iridium/​cm² began ser­i­ous test­ing in 2023. The res­ults showed that fur­ther research into how Smol­tek’s nano­struc­tures can be con­figured to sur­vive in the harsh elec­tro­chem­ic­al envir­on­ment of an elec­tro­lyz­er cell could make it pos­sible to reach down to 0.1 mg iridium/​cm².

High iridi­um usage has long been a major tech­nic­al chal­lenge for the rap­idly grow­ing green hydro­gen industry pro­duced from inter­mit­tent energy sources such as sol­ar and wind power, as today’s con­ven­tion­al PEM elec­tro­lyz­ers use around 2.0 mg iridium/​cm². The res­ults from last year’s reli­ab­il­ity test with 0.2 mg iridium/​cm² made a big impres­sion in the hydro­gen industry, and the com­pany received inquir­ies from sev­er­al poten­tial cus­tom­ers who expressed interest in con­duct­ing their own tests of the technology.

Our tech­no­logy is expec­ted to sig­ni­fic­antly reduce the costs of pro­du­cing PEM cells. Pre­vi­ously, the will­ing­ness to invest in PEM elec­tro­lyz­ers has been lim­ited by high costs for, among oth­er things, iridi­um, but now we have proven that we have a solu­tion to this chal­lenge and are well pre­pared for the major growth that is now being scaled up globally.

^{Ellinor Ehrn­berg, Pres­id­ent of Smol­tek Hydrogen}

Read the offi­cial press release of this news.