Ivan: Some where in your articles it would be helpfull to discuss the shipping issues with different battery chemistryies. This is something that can catch both designers and PM's off guard, at least the first time they go thru it. :)
Crusty1: There are many 'rejuvinator' devices that are used here in the states for large truck batteries. If you can get an extra couple of months usage out of a battery it is worth the 8-10 hours that the process takes.
Also, Nickel Cadmium types were notorious for growing metal-fiber 'wires', that would partially short out a cell. There appeared a capacitor-based rejuvenator that would pulse a high-current into the cell to blow out the metal fibers and breathe new life. A similar treatment was touted to break loose sulfation in lead-acid cells. The applied voltage waveform shape and duration was critical to keep from doing too much damage. In some cases, it killed the remaining life, but was sometimes worth the risk.
This is mainly for non-rechargables (acctually it could apply to rechargable too). Is there a standard load voltage drop vs load that's used to indicate the internal battery resistance is to high for practical use ? Digital cameras tend to be very picky about power supply. I've taken digitial camera batteries deemed BAD by the camera and used them succesfully in other less picky electronics. ( I wouldn't suggest using them in a pace maker). This begs the question: Are we discarding nearly good batteries ? Maybe recycling usefull batteries or worse sending them to the land fill.
As a hearing aid engineer (and one of 8.5 million users) I'm particularly interested in zinc-air technology, specifically with humidity. One engineer I know calls it a fuel cell, but nstead of pumping in O2 it extracts it out of the air.
Useful for what to whome? That was the midevil period though so anything "strange" might have branded you a witch.. without Generators to charge batteries you couldn't do much - and we didn't have generators until 1873, but wow things cascaded quickly once we had power generation.
I am very interested in this subject and wish today's products would be made compatible with rechargable lithium cells running at 3.7v and normal alkalines at 1.5v so we could start having AAA, AA, 9V (3.7x3), etc pure lithium cells. I know it might be somewhat tricky, but it would be nice to get rid of heavy, single use, low power density alkaline land fille batteries for good. With the speed we replace electronics these day's it wouldn't take long.