I got some new Altoids tins, borrowed a Dremel tool from Mitchell, and purchased brand new firewire connectors from NTC. Here’s my second, cleaner, tighter, much nicer attempt at a sweet external battery pack for iPod. Once, again, credit goes to Drew Perry for the design and inspiration. His is made inside a deck of cards, mine is in an Altoids can. This one is way better than the first one I tried, and my soldering is getting better – not really.
What do you think? Getting good, huh?
There has been so much interest in this project from all over the world I can’t believe it. There have been great suggestions for improvements, and some questions about how, exactly, to build one. So, I thought I would add some information to this post and get the information out there.
First of all, let me once again thank Drew Perry for the schematic and the original battery pack idea. He did most of the heavy lifting. Let me also acknowledge unixmonkey, who actually created an Altoids Battery pack before I did, though I didn’t know about it until after this project got so much exposure. His battery layout is different, but he also used Drew’s schematic and project as inspiration.
So, let me start with the schematic. The following is pulled directly from Drew Perry’s site. It shows exactly how the batteries should be wired together. As you can see, it is a very simply circuit, a perfect beginner’s project.
As far as the firewire port, I chose the RFS-6602, the “Vertical 6 pin receptacle, through hole type” (3rd one down on this page on NTC) because is is smooth and can slide easily through a hole in the Altoids tin. The original one I built used a salvaged port from an old firewire card I had, and it sucked – it was so sloppy and awkward to install.
As far as the pins go, Pin 1 is for the power, and pin 2 is for the Ground. It’s quite easy to figure out, but it took me some time. I bought a $14 Multitester at Radio Shack to help me figure it out. If you look at the schematic here below, pulled directly from pinouts.ru you can see clearly where pins 1 and 2 are.
That should help. It is tricky to solder the wires and keep these wires apart, and I suck at soldering. unixmonkey took a great step after this, which I will do to my next model. He simply smothers this connection with hot glue, to ensure there will be no short. Good idea. Mine is sort of dangerous.
So, you follow the diagram, solder it together, and check the voltage outputs. Should be between 11 and 12 volts. That’s it. It’s really very simple. I am embarassed by all this attention.
I also saw some comments on hackaday and engadget suggesting the batteries might unevenly discharge or produce unstable voltage. These are valid concerns. One commenter suggested a power regulator circuit board. I am going to look into it and maybe add it to the design. I hope I can get one to fit.
Rechargeable batteries could totally work, but the point of this project was to have a power source when recharging was not an option. If you were going camping, theoretically you could throw a whole bunch of regular alkaline batteries in your pack and you’d be good to go for the weekend.
Some other people have expressed concern over airport security and my little experiement. I am also a little worried about airport security, but am willing to give it a go. There is a high liklihood that I will get stopped and THOROUGHLY searched. Wish me luck.
Lastly, I am working on some improvements and other projects. I love squeezing stuff into Altoids cans, so look forward to new stuff soon.
UPDATE (1/17/05): I made a new version using just a 9V battery this time, and put it into an Altoids Chewing Gum tin instead of the fullsize one. I’m very happy with the result. Have a look at the iPod Altoids Mini.