Best Charger for iPhone 3G

[Sparky_92]

I had my iphone 3G down to about 20% battery before leaving on an hour long road trip. With the phone unlocked, bluetooth and nav…

the battery dipped below 10% with constant warnings and was nearly gone by the end of the trip. I have read in various forums this is because the 500ma output from this charger can't keep up with the 3g in these conditions.

I am now looking for a device with 1000ma support (like the apple wall charger). When I went back to the apple store some of the reps knew about the problem but couldn't recommend anything else as the ratings of the chargers are not listed on the boxes.

Thoughts?

[tonepod]

I think there are a few cheap (i.e., no-name brands sold on Ebay and other lesser-known online stores) chargers that advertise as having 1A output; however, I don't think even that might make a difference because a theory that's going around is that there's some kind of thermal overload protection in the iPhone which shuts down the charging circuit if the iPhone operating temp reaches a certain point. I mention this because:

1) It is pretty well known that the iPhone gets (and feels) pretty warm when the GPS is active for any decent length of time (e.g., Google Maps running for 30 minutes or so);

2) When connected to a car charger and with GPS active, the iPhone "appeared" to be charging just fine--it even displayed the "plug" icon (vs. the "lightning" icon) after a short while (battery was near-full prior to charging), which usually indicates that the battery is at full capacity...but after about an hour later, I looked at the battery meter--it was showing only about 1/3rd full.

Now, it is still a possibility that having GPS/BT/3G all on at the same time drains the battery faster than the car charger can recharge it...but the thermal overload theory is also possible.