Talk:Nickel-Iron Battery
On toxicity and other safety concerns:
Nickel oxide/hyroxide is indeed toxic, but as it would be contained in a battery, it seems this is likely the best place for such a substance to be. Basic safety protocol should keep anyone who should have to handle the battery and/or its components safe from harm.
Lye isn't 'toxic' it's caustic and corrosive. Either way, it doesn't get along with the body very well. However, once built, the lye will be diluted in a solution (ideally of glycerol), and so there shouldn't be much danger at all associated with the battery once built. However, utmost caution should be exercised when mixing the electrolyte (which shouldn't be a problem if waste glycerine from biodiesel production is used).
Unfortunately, nickel is also a strategic metal, which does add to its cost, but further research may point the way to better localized sources. Of course, this shouldn't be an issue as each 1kWh battery has a one time cost of 2kg nickel (as is explained in the page). All in all, I think NiFe chemistry is about the safest practical battery that could be constructed. Colin 14:45, 16 May 2011 (PDT)
Feel free to edit the section I added on toxicity, I just wanted to make sure that something was there. Yes, lye is corrosive, but I do agree that handled correctly, it can be safe. We might want to add links/comments to the effect that lye can be made from wood ashes.
You might want to do a bit of sourcing for nickel. I wonder how much it costs. - Mark J Norton
I was curious, so I did a quick search and ran the numbers myself. $251.50 for 2kg of nickel. - 5/16/11 at 9:05pm PDT
On sources of nickel: because of cost, I have been thinking about the best starting material for nickel. It seems best to me to start with nickel hydroxide mixed in with the electrolyte, in the appropriate concentration. A small amount of something like nickel nitrate might be needed to provide a thin coat of nickel metal, but I think that the hydroxide by itself should work. In either case, it makes the most sense to start with nickel, and treat it with the appropriate acids and bases to get the form we want. This way, we could even start with nickel shavings, ingots, blanks, or any other form of nickel. Colin 20:47, 24 May 2011 (PDT)
Let me elaborate on the above. The construction technique I'm envisioning for this battery involves a number of plates, all made from relatively thin sheet steel. Half of which would be plated by nickel oxyhydroxide in the first charging cycle, forming the cathode of each 1.2V cell. The steel should be carbon steel with minimal to no content of other metal. I intend on writing this into the article, but I think that it needs graphics to go along. So, the idea is that the sheets which will be the electrodes would have a tab cut out of a corner with the cnc torch table. Then, these sheets will be placed with the remaining tab (like a tab on a folder) of each plate alternating in a cell. This leaves two sets of 'tabs,' one set will be for the anode, and the other for the cathode. With this design, two long steel bars can be welded to the exposed tabs, which should allow for high current capacity, resilience, and rigidity in design. These two bars would be inside the profile of the box when viewing it from the top, so many cells can be placed snugly adjacent to each other, and then welded in series to form a 12V stack. Such a setup should easily handle the highest loads this battery should be capable of driving. Colin 20:55, 24 May 2011 (PDT)
The added information to the article is greatly appreciated, but tends to be overwhelming. At this point, I suggest this article is broken into two segments: chemistry and construction details. Anyone else agree with me? Colin 21:26, 24 May 2011 (PDT)