....Final issue is the juice in the cells.
It is a concentrated Potassium Hydroxide fluid. New cells have several drops of extra liquid, and the inter plate separators are well saturated, but all the old used cells that I have dissected are pretty dry, and show sections of blackened very dry separators....
Great information. I had been wondering what exactly the electrolyte looks like - and imagining, erroneously, that it was a free flowing liquid inside the cells. But then, I had been examining some picts at your website of disassembled cells, and now your summary above: saturated separators with "several drops of extra liquid" in new cells; old cells "pretty dry"... Now I shouldn't have to cut open any batteries, at least for now...
One other thing I wanted to mention, after re-reading a bit of this thread. It has to do with 'how low do you go?', the difference, if any, between a battery drained via prolonged self-discharge vs. a manual 'super' deep discharge, etc. Of course I don't know anything along these lines for sure, and I'm no electrochemistry expert, not even close. BUT, my hunch is that it shouldn't matter what means are used to get cell voltages low, as long as all cells DO get low.
I think that's the critical difference: most of the manual discharges have been at relatively higher rates (i.e. relative to the rate of a self-discharge), on multiple cells in series, and usually not to very low voltages. The result is that not all cells reach the critical low voltage threshold - so not all cells get 'fixed', and performance doesn't bounce back as you'd expect or want. But a prolonged self-discharge DOES drain all the cells to that critical low threshold (I'm thinking 0.19V-0.78V per cell, yet really interpreting the research as indicating 0.19V, all else being equal).
Point is, based on my reading, once you see that critical voltage, it indicates that this or that 'phase' is gone - it's like a chemical, scientific fact: you see this or that potential/voltage because this or that chemistry is going on; if you don't see this or that voltage then this or that chemistry is no longer happening. So, I don't think it matters how the cells get low, so long as they get low. I mean, it matters for other reasons - like you wouldn't use a 50A load to take 120 cells down to 0 volts. But it doesn't, or shouldn't, matter in terms of getting rid of voltage depression, as I understand it...
One aspect that remains a bit unclear to me is the variation one might see in the real-world vs. the technical/theoretical values. For example, I'm using 0.19V-0.78V based on my interpretation of stuff in that book. And then, I saw about 0.63V for each cell in those sticks that sat for a year. And Keith saw similar values. Of course there will be variation based on measuring instruments; that's not really what I'm concerned about.
I'm concerned about the meaning of that range between, say, 0V and 0.78V. In my limited experience it has seemed as though there's very little difference, capacity-wise, performance-wise, functionally, between say 0.63V and zero. For example, you stick a 75w bulb on a pack with all the cells at 0.63V or zero, and in either case the bulb is going to be dark or go dark in seconds. The extent to which it doesn't simply reflects the extent to which some cells are not discharged as much...
Point is, there's wiggle room in these numbers - such as 0.19V per cell - when it comes to the realities of doing the work, discharging the packs or sticks or individual cells, measuring, etc... The technical/theoretical value is cut and dried - or it is in the sense that, if we've picked the right number, by nature it is cut and dried; generalizing that value to the work we have to do is a bit different.
If, for example, that critical threshold IS 0.19V, how do you ensure that each cell in a 120 cell series reaches it (barring 120 DVMs)? It seems like, you can only be sure if you take the pack to zero...
Anyway, I think I mentioned before that the great task seems to just boil down to discharging the pack or stick or whatever more or less completely. Light bulbs, fixed watt resistors - things that complete the task with lower and lower currents the lower the state of charge gets, seem to do it, seem to be the way to go. You try to limit the number and duration of cell reversals as much as possible, by whatever means; the lower the pack gets the less deeply reversed cells will be driven; etc. etc...