We meet again at May 9, this time at the NanoEnergieTechnikZentrum, NETZ. Leander is back from his holidays and amazingly added lots of CAD files to the website. Roland brought a package that was shipped to my name but it contained nothing related to the Open Fuel Cell but Merch for to the Pint of Science Festival which I organized around that time. This sparked a discussed about Open Fuel Cell Merch and a Logo – but first things first.
Livia asks how many of the sealings we need for one cell. Burghard says it’s two and looks at the sealings. The sealings of the original Open Fuel Cell were printed by Burghard using a filament with a scab hardness of 70. Livia printed the new sealings with a scab hardness of 90. So, we still need to check if they will be gas-proof after assembly.
Alexandra and Roland report that they made a few more MEAs by pressing the catalyst coated gas diffusion layers onto the proton exchange membrane. Then they ironed the rim together – Burghard calls this process precision ironing.
But the big project of today is electroplating. We finally gathered all the equipment – we have
- the electroplating set from Amazon
- the new 3D-printed tank, this time with the long side being the open one
- the stainless steel electrode which I ordered online
- a metal wall setup which Livia brought to help holding the electrodes in place
- a gold electrolyte which we also ordered on Amazon
- two different Nickel electrolytes
The story behind the Nickel electrolytes is this: A few weeks ago we had to realize that as a private customer, one cannot order this Nickel Electrolyte from Tiffoo (which was used before at the Chair of manufacturing engineering and at ZBT). However, we found a different provider, from which we were able to order Nickel electrolyte as a private customer. SInce we want all OFC components to be as accessible as possible, we ordered this one. For reasons which will become apparent later on, we will refer to the former one as the “good stuff” and the ladder one as the “crappy stuff”.
We are excited to finally make our first lab visit (our building technician was not amused when I asked him if we could electroplate in the seminar room). He referred us to a lab which is currently not used. So we carry all the stuff over there.
The lab is pretty empty. I even had to go to another lab to ask for some deionized water and some isopropanol for cleaning. We set up the electrode plating setup and fill the tank with the Nickel electrolyte (the “crappy stuff”). I am excited, dutifully wear nitrile gloves and lab goggles, and – under Roland’s observing gaze – put the PCB plate into the tank. One cable is connected to the plate, the other one to the stainless steel electrode in the tank. I start tuning through the different voltage and amp settings at the power source. Roland draws my attention to the bubbles that form on the PCB plate surface and tells me that this is a good sign. We are probably depositing Nickel onto the plate, he says. After a minute or so, he says thinks it should be enough and we switch off the power and take out the plate. It looks weird. Not silver at all. Rather smeary.
We try again. More bubbles, no silverish deposition on the plate. We are pretty clueless, so I start running around in the NETZ building searching for people with some solid electrochemistry knowledge. I find Ignatio and bring him to our lab. He also has no idea why we have no Nickel deposition.
Anyway, after a while of systematic testing we found the solution (pun intended): if we used the Nickel electrolyte from Tifoo (the one that can only be shipped to business customers), we manage to get a nice deposition within just about a minute, using the same settings which we used for the other Nickel electrolyte (the one which can be ordered as a private person. The bottles don’t really tell us an awful lot about concentrations or anything. I am sure we could inquire, but for now the most important thing for us to note is that we managed to do Nickel electroplating! It’s just a bit unfortunate that it needs the one that private persons can’t order.
