Im looking for literature or ideas, how to seal electrochemical cells for oled or electrochromic useage. Those cells usually contain liquid solvents containing electrolytes and air sensitive molecules, that "die" if oxygen or vapour enters the cell.
So i need a technique, that allows very air tight sealing, but also does not require temperatures above 150°C or extreme pressure. Many polymer films or seals are not tight enough. In addition i need to fill the cell with the liquid and cannot allow any air bubbles, which excludes many procedures.
I know commertial products have the same requirements, so there must be some solutions to these problems, but i really have trouble finding them.
I would suggest to consider UV polymerization of acrylated monomers and oligomers.
I would encourage you to visit the following links below and discuss the matter with the agent (online help), may be he can guide you in the right direction:
https://www.pineinst.com/echem/productsubcats.asp?categoryID=20
http://adamschittenden.com/electrochemical%20cells.php
Hope this helps.
Tin, indium, gold and indium-gold alloy wires are suitable as relative soft but vacuum-tight materials; low pressure or ultrasonic is enough for joint. Red copper cement seems to be fit (for glass) - it need some time to hardening. It is lab (not industrial) solution
Try contacting Delo Adhesives. UV curable epoxy resins. Try their Katiobond range of glues. What are you gluing? ITO, glass, plastic?
Im gluing two glass substrates, with ITO layers so the surface can be either ITO or glass. The problem is, the molecules envolved, mainly viologenes and phenazines are reduced and oxidizes for their functionalty in the latter cell. But upon construction heavy reduction or oxidation in their environment leads to "overoxidation" and often destroys the function of the molecules. I already tried katiobond and some two componend epoxy, but they use redox reactions for hardening, which destroyed my molecules, so they are not working.
I have no experience with the metal alloy wires, i will certainly look into this. They might be problematic thou, because they might short some contact, or are not stable against electrochemistry, but they might work, so thanks very much.
Very interesting. Now that you mention it we also get the same phenomenon happening in our cells when we use ITO coated polycarbonate when using UV curable glue. For ITO coated glass we do not have problems. The polymers die around the edge and form a halo. Optical transmission below about 420nm through PC is not good and we were surprised that the glue was curing at all. We use a high intensity UV wand. But I suspect that the glue is only partially curing and that we are getting migration of the uncured hardner into the polymers which is causing unwanted redox reactions. One of my work colleagues was talking to a former Gentex person and said that they were unable to get the UV curable glues to work and ended up using thermal cure glues. Can your polymers cope with 120-130C temperatures? Perhaps thermal glues are the better option.
I am already looking into thermal cure glues, problematic is the expansion of the liquid electrolyte, but it seems to be an option. Very intereseting that you mentioned gentex we were actually discussing to buy one of their mirrors and see how they capsulte them, but i think that is obsolete now =).
Any thermal curing glues that you can recommend?
For Laboratory solution, you may try to use Aluminium foil (kitchen rolls) coated with some very thin layer of glue (cyanocrylate for example) or coated with a very thin layer of wax (petroleum or polyethylene wax). Aluminium is a total barrier. If you glue the both sides of the electrochromic with the aluminium foil (U shape) then you may have a higher level of airtightness. Prefer thick aluminium foil (100-150µm) as Aluminium has poor mechanical resistance.
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