Solution: Use a single LiFePO4 3.2V AA cell coupled with a dummy cell.
LiFePO4 is Lithium Iron Phosphate, a safer alternative to the usual Lithium Ion or Lithium Polymer. See http://en.wikipedia.org/wiki/Lifepo4
The dummy cell is just a chunk of wood filed down to be cylindrical and the same length as a AA cell. A hole is drilled down the center and a 2″ long wood screw is screwed in. The end of the screw would be ground down, as it is usually too sharp to put into the battery enclosure. One can also put a small amount of crushed aluminum foil over the end of the screw so that it fits nicely in the battery enclosure.
Although LiFePO4 batteries are safer than most Lithium-based batteries but this comes at a price: About half or third the power capacity. Fortunately, because they hold their voltage well over their discharge cycle, this isn't a big problem on cameras. Plus you can carry extra as they are light and you only need one when in the past you needed two!
A few cautionsRead More...
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