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.