Photo-activated Acid Battery

[FrankG]

The concept below has been on my mind for the last week or so, and I thought this might be the best place to discuss it...

Is there such a thing as a "Photo-Activated Acid", or for that matter a "Photo-Activated Aklaline" compound?

The idea being that if such a chemical compound existed, and could be made soluable in an electrolyte suspension, it could be used as both the collector and storage device.

Initially my thought is of a flat (horizontal) cell that would be litterally charged by the sun, if surface are was an issue (and adequate ionic differential between the dis-similar metallic anode/cathode plates) a pump could circulate the electrolyte to the top of an inclined plane that would spread the liquid over a greater surface.

My electro-chemical fantasy is scalable to create landscaped acidic water features around ones house (under glass) or integrated into shallow roofs as needed.

Unfortunately I have neither the time nor background to take such a concept beyond "gee I wonder" type thought exercises... Though would appreciate any feedback (both pro and con) on whether this is a realistic idea...

All the best!

FrankG

www.theworkshop.ca

frank@theworkshop.ca

[Ungrounded Lightning Rod]

I've seen a rechargable (nicad, I think) with solar cells built into the side.

I think the idea was to pop a couple of 'em into a flashlight with a transparent plastic housing and leave it on the windowsill or otherwise exposed to light.  That way it stays fully charged and any time you need it it's ready.

Photovoltaic is a bit more complex than something you can pour into the electrolyte of a battery (at least currently) and high-energy-density storage chemistries are very hostile environments.  Thus I don't think you'll be seeing something like you described any time soon.

Even life processes (which have to do something like you describe) keep the energy factory separate from the rest of the machinery by membranes in separate organelles (chloroplasts, mitochondria), just because of this issue.  And most plants that use photosynthesys-gathered energy from those organelles to make relatively benign sugar from CO2 and water then have to polimerize the sugar into starch to keep it from raising the osmotic pressure and blasting the cell apart.

The closest I've heard to what you descirbe is an organic system that makes hydrogen gas when exposed to light.  But even there the hydrogen isn't stored at high density in the solar collecting system for later use in an integral fuel-cell.  Instead it needs to be bubbled off and collected.

[richhagen]

Hi Frank, While I am not aware of any chemicals that could be used to do what you want, my main reason for responding was to ask you how your TWS-1850 is coming along.  Rich

[FrankG]

Ungrounded,

Your thoughts are right on track with where I was headed, ie; mimic nature and the Photosynthisis process, but agree that the practice is far trickier than that theory.

Ideally if the process was inorganic, and the electrolyte would simple raise it's pH under the influence of photons and lower it's pH under discharge we'd all be rolling in surplus energy...

What little I could find on the web related to some sort of peptide or ammino acid that was being used for DNA type research, and it's pH could be manipulated by exposure to light... Not at all on the scale that I was hoping for...

...fg

[FrankG]

Hey Rich,

The large mill ground to a halt last spring for a number of reasons... I built another mill for a local business here in town and that took a couple of months...

But the main issue was driving multiple steppers synchronously per axis as well as implementing some sort of current limiting scheme (beyond dropping voltage through large resistors)...

I have half of the solution designed and working, but may still have to use some resistors to limit stepper current. Where the project is really stalled is that the company that has one of my mills wants the larger unit (TWS-1850)... But since they encountered such a steep learning curve and had staffing problems, I felt that the remainder of the mill should be completed with thier main operator on-site over say 4 or 5 full days.

It's frustrating to say the least in that I would like to either get it out of the shop or finish it for my own use, but lack the enthusiasm to build a unit that is for another...

It is currently just a bench that has all my EV related batteries stored inside on it.

I'm glad that you've asked about it though as it should be finshed regardless of the circumstances.

[richhagen]

Well, you've always got a few irons in the fire, so to speak.  I enjoy reading your projects, and have been working on larger cnc machines.  I have acquired a more primative JRGO (a type by that name built from free plans available at CNCZone.com)type router with 24" of travel that I am trying to configure.  The metal one I started with 40" of travel has similarly ground to a halt as the linear bearings I selected were too thin and have too much sag for the gantry.  When I get around to it I will probably figure out a work around.  At any rate, I keep an eye on your site (www.theworkshop.ca) and look forward to your postings there.  Rich