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AC Power from a Battery Answered

I've got a Garmin Forerunner 201 that is recharged by plugging a cord into the wall socket. It has a cradle type device that serves to connect the device to the cord. It does not have a USB connector.

The battery life is 12 hours, but I'm going on a four-day bike ride (camping overnight), so I need a way to charge it since I won't have access to AC power.

I've searched projects and gotten lots of hits on creating a USB charger from batteries, but I can't find anything on creating a power pack (with outlet) for charging my device.

Does anyone have any suggestions on what I could do/use? I'd hate to not be able to track my route after I'm done.


According to the Garmin accessories page, it uses a power adapter, not just straight AC input. What is the output rating on the wall adapter? It would be easier to just get the straight DC output from the adapter than taking a battery pack/solar panel/whatever from DC to AC and back to DC.

It takes 5v (which IIRC is what is provided by a USB cable). If I read between the lines, what you're suggesting would be to convert the cradle from using AC to DC (which could then use an Altoids USB charger battery pack). Is that correct?

The cradle already uses 5VDC. I'm guessing that there is a plug to attache the adapter to the cradle, and that it isn't permanently attached. If that is the case, all you have to do is find the same size plug and wire it to a MintyBoost, if that is the circuit you wish to use. Any 5VDC source will work.

That's the route I've decided to take. I'll clip the power adapter from the cord and wire it up to a USB cable. I checked out minty boost, but the kits are out of stock at the moment. Since the trip is in three weeks, I plan on making something like the one found here (inspired by mintyboost) so I have something in case I can't get it before then.

Go to any store and ask for an inverter. Most auto stores also have them. They take 12v dc and convert it to ac. You will also need a 12v battery pack (jump starter pack)

Thanks for the suggestion, but I'll be on a bicycle and will be trying to limit the amount of weight I'll be carrying.