Hi,
I just got an arduino fio and have no idea what li-po battery would work best in powering it. What voltage and amperage?
thanks in advance
The FIO runs at 3.3 volts. Thus, likely a single LiPo cell of 3.7V will be enough. I recommend reading the description / data sheet for the FIO to make sure, though.
The amperage doesn't matter much -- the bigger it is (in mAh, meaning energy content,) the longer it runs, but no reasonable LiPo cell will be unable to supply the 50 mA or so the AVR will draw.
It is unlikely the Fio is the only thing you'll be powering with the battery. You need to consider what the consumption of your total circuit is and how long you want it to run.
I don't think the fio will draw 50mA; it has a much more efficient voltage regulator than the typical 5V arduino's, plus it's running at 8MHz and at 3.3V. I'd expect something less than 20mA.
I have one that run's for a couple of months from a 6000mAH 3.7V lipo with a XBee attached (adds 45mA). It sleeps for 10 minutes between sensor readings.
I'm also testing one with a 2000mAH 3.7V lipo and an nrf24l01p which only adds 13mA to the current draw.