I realize that the rechargable alkaline cells would be more expensive than a motorcycle battery, the charger would be more expensive, and I'd have to replace the alk. cells more frequently then the motorcycle battery. I'm willing to spend the extra $$$ if it will buy me more portability and less mess and hassle, and if the D cells will in fact be adequate.
I think the D cells should give me 12 amp-hours, which is about what many small lead-acid batteries are good for. I suspect that this might be adequate for my needs, particularly since the corrector plate is relatively small and should not require nearly as much heat as an 8" or 10" SCT corrector to keep it dew-free. I arrived at the 12 amp-hour figure as follows: 1. I measured the discharge curve of a conventional alkaline AA penlight cell, and found that it had put out 1.5 amp-hours by the time the cell voltage had dropped from 1.5 volts to 1.15 volts. It actually put out nearly 2 amp- hours by the time the discharge curve took a nose dive and the cell was really dead. 2. I assume that amp-hour capacity is directly proportional to cell volume, for two cells of the SAME DESIGN, but different sizes. I measured a D cell and a AA cell, and found that the volume ratio was roughly 12/1.5, so a _conventional_ alkaline D cell should be good for 12 amp-hours. 3. Further assuming that a _rechargable_ alk. D cell has the same capacity as a _conventional_ alk. D cell, so it should also be good for 12 amp-hours.
Does anyone have any experience using rechargable alkaline cells for doing this? Can anyone think of any potential problems? Is 12 amp-hours enough? Is there any other type of battery I should be also considering?
Thanks in advance for any info. -- Gerry