I have a bunch of AA sized Nimn batteries that I want to keep charged.
For some applications, I have put into a PVC tube to make a 12v battery pack. (See http://www.fieldlines.com/story/2007/3/8/144911/7099 ). Because I already had this "pack" made, I've been hooking up a 12V 1A power supply directly to the pack in order to charge the batteries.
The problem is that I have an odd number of batteries. 10 batteries makes a 12V pack, but I have something like 23 - not divisible by 10.
I was thinking of ditching the pack idea (for charging) and rigging up a charging "bus line" that ran something closer to the voltage of a single cell. Then I'd put the cells in parallel, and it wouldn't matter if I was charging 1 or 100. Would that work? I figured if a cell was near dead, it would keep the line voltage below 1.2 volts, and if they were all charged, the supply voltage would keep them all charged up?
Another question, does the voltage matter that much, or is it the current that matters? Do I have to use something that puts out only 1.2 volts, or can I use something like, say, a CD-Player adapter (4.5v), or can I use a 12v supply, or do I need to ignore the voltage and instead concentrate on getting the correct amperage? I'm hoping to not have to babysit them.
Thanks!