Here’s a cool way to make your own battery pack with a little voltmeter!
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!