Smoltek Hydrogen has successfully completed a long-term electrolyzer cell test

Smol­tek Hydro­gen has com­pleted a suc­cess­ful long-term test of our newly developed mater­i­al for PEM elec­tro­lyz­er cells. Dur­ing 1000 hours of con­tinu­ous oper­a­tion, at 2 A/​cm², we have pro­duced hydro­gen with only 0.2 mg iridium/​cm² without any degrad­a­tion of the nano­struc­ture in the cell hav­ing occurred. The mater­i­al, which con­sists of a cor­ro­sion-pro­tec­ted car­bon nano­struc­ture, forms one of the lay­ers in an elec­tro­lyz­er cell and the tech­no­logy aims to sig­ni­fic­antly reduce the amount of iridi­um used as cata­lysts to pro­duce hydrogen.

We have now proven that our tech­no­logy with car­bon nan­ofibers, coated with plat­in­um, cre­ates a stable struc­ture in an anode elec­trode in a PEM elec­tro­lyz­er. Our com­pet­it­ive ana­lys­is shows that we are the only one with a work­ing solu­tion for the anode side elec­trode, which is both dur­able and cre­ates a large sur­face area for the iridi­um cata­lysts. This rep­res­ents an import­ant mile­stone for the com­pany and for our dia­logues with col­lab­or­a­tion partners. 

Ellinor Ehrn­berg, Pres­id­ent of Smol­tek Hydrogen

Full-cell per­form­ance meas­ure­ments show that we have per­form­ance com­par­able to con­ven­tion­al solu­tions, with only one-tenth as much iridi­um! Dur­ing the first 10 hours of the test, the voltage rises from 2.1 to 2.5 volts, then increases only mar­gin­ally. This is not abnor­mal for a pro­cess like this in a lab envir­on­ment and it is some­thing we will optim­ize in the next step in col­lab­or­a­tion with cus­tom­ers, for example by using dif­fer­ent types of iridi­um and per­haps also ruthenium. 

Fabi­an Wenger, head of devel­op­ment at Smol­tek Hydrogen

The thing that has been most ques­tioned dur­ing the devel­op­ment of this tech­no­logy is how we could cre­ate such a con­form­al lay­er of plat­in­um that it can pro­tect the car­bon nan­ofibers against cor­ro­sion. Now, after 1,000 hours of con­tinu­ous oper­a­tion at 60°C, the fiber struc­ture is intact and we proudly state that we have solved the most import­ant ques­tion from both part­ners and com­pet­it­ors: how to cre­ate a stable nano­struc­ture for an extremely thin iridi­um layer. 

Ellinor Ehrn­berg, Pres­id­ent of Smol­tek Hydrogen

Great pro­gress in a short peri­od of time
In a short time, Smol­tek Hydro­gen has made great pro­gress towards sig­ni­fic­antly redu­cing the amount of iridi­um in the anode side elec­trode in elec­tro­lyz­er cells by using nan­ofibers as the struc­ture for the cata­lys­is in the cell stack. In the spring of 2023, the com­pany demon­strated that the newly developed mater­i­al tech­no­logy with cor­ro­sion-pro­tec­ted nan­ofibers could reduce the amount of iridi­um by 80 per­cent com­pared to a con­ven­tion­al mater­i­al (0.5 mg iridium/​cm² com­pared to 2.5 mg iridium/​cm²). This in an ini­tial long-term test with an early pro­to­type of the cell mater­i­al.
 
“Through the estab­lish­ment of our own devel­op­ment and test labor­at­ory, H2LAB, includ­ing col­lab­or­a­tions with world-lead­ing research­ers and part­ners, we have been able to accel­er­ate R&D, which has increased the per­form­ance of our cell mater­i­al for PEM elec­tro­lys­ers”, Ellinor Ehrn­berg explains.
 
Smol­tek Hydro­gen aims to reduce the amount of iridi­um in the elec­tro­lyz­er cell towards 0.1 mg/​cm². It is an ambi­tion that aligns with the hydro­gen industry’s goal to be able to scale up the pro­duc­tion of elec­tro­lys­ers for large-scale pro­duc­tion of fossil-free hydro­gen. Iridi­um is a very expens­ive and crit­ic­al pre­cious met­al with lim­ited sup­ply. Today it costs about SEK 1.7 million/​kg and is fore­cast to cost about SEK 8 million/​kg in 2030.