The little-known AAAA battery can be very useful indeed. It’s very small, and thus can be crammed into tight spaces. It’s nearly as compact as some of the larger lithium coin cells that you might reach for in a small project. However, it can still maintain the high current draw of a big alkaline dry cell, unlike the lithium chemistries. If you have a project where you need to draw 100+mA continuously, but space is tight, AAAA cells are just the thing. Some calculators, MP3 players, and remote controls also use these.
While working on just such a project, I found myself needing four AAAA batteries. Then I looked at the price tag- yikes! At my local drugstore, the pack you see here is over $6. That’s about three bucks EACH. Highway robbery.
So here’s the hack. I’m probably the last person on earth to figure this out, but guess what’s inside a standard rectangular 9V battery?
Six(!) AAAA batteries. Yep, six. A pack of four 9V batteries at the same drugstore is $14. That’s 58 cents per AAAA battery, or a savings of about 80%.
So there you go- next time you need a AAAA battery, buy the 9V on the shelf next to it instead and stick it to the man. Down with Big Battery!