Doug Wilson has built a cool Altoids battery pack! Not sure what it is about the Altoids tins, but it seems that projects make great use out of them! This one seems to have all the bells and whistles. If you are looking for inspiration there are full build details on the site.
“I have a 10 cell ‘AA’ NiMH battery pack (12V @ 1.6AH) that I use for backpacking. It needed a home! I also wanted a voltmeter built-in so I could keep track of it’s condition and charging (I live in the woods, you have to keep chasing the sun with your solar panel..). Radio Shack didn’t have any cases / boxes that suited me so I got thinking about that Super-Sized Giant Altoids tin I had and thought it might work. Bingo! The battery pack, LED voltmeter ( www.rainbowkits.com ), switches and connectors all just fit!
Actually, I’m telling a little white lie – don’t go off to the market to find that jumbo-sized Altoids tin, I made it by cutting the bottoms out of 3 regular tins and soldering them all together with a 4th.. A lot of folks use the Altoids tins for QRPp rigs, so I started to think of them not as just a project box, but as a project form-factor. A four unit high box fit my needs perfectly.”