Mine is definitely different speeds.

 

As I've read in the past and seem to experience with my phone, plugging into the wall and in the car charges more rapidly than plugging into the computer. I believe that the computer does more of a trickle charge.

 

It'll likely charge faster off of an AC outlet or car adapter than USB. A lot of the AC/Car adapters can put out 1A vs 500mA off of USB.

 

definitely a fact you made.

my stock ac charger id say is the fastest. the usb charger i have in my car is super slow.

 

As I understand it they should be about 5 Volts at the connection whether it is a car charger, wall charger, or home charger. So in theory they should all charge at the same rate.

 

the little tag on my cable says 3.0 hours AC and 7.0 hours USB

 

They have different amperages though. Voltage is how much energy is available, but amperage is how fast it's moving, so to speak. The higher the amperage, the faster the battery would fill up.

I imagine the Eris limits how much it draws though. I'm just not sure what that level is.

 

Yeah, I forgot about the amperage thing

 

Ohm's Law.

 

Yep, its all in the amperage. If you take your battery capacity in mAh, divided by your charger's mAh rating, that's a rough estimate of how long it should (in hours) take the battery to charge from completely dead to full.

Computer USB is pretty weak in that regard. With it only outputting 500 mAh. Most dedicated chargers I've seen go 700+ mAh.

 

i definitely notice a difference... i've left my phone charging overnight on my computer (after going to bed pretty late...) and when i wake up it isn't fully charged... on the other hand after charging for just a few hours on the AC charger its done!

 

Charging speed depends on amperage more than voltage. USB puts out 5V @ 500mA while a dedicated charger will put out 5V @ 1A. Dedicated chargers will charge a phone twice as fast as a USB port will.

Voltage is equal to energy per unit charge. Amperage is the rate of flow of electric charge. So to put this in simpler terms.

Imagine a highway, the lanes are all the same width (voltage), the cars all travel at the same speed (speed of light, approximately), but the cars are of different sizes (amperage). So if you want to deliver the most payload in the shortest amount of time, you'd use something with the highest amperage that the road would tolerate (too heavy a load will damage the road). Trying to use more voltage (a wider car) would cause an "accident" (you'd fry something).

See, wasn't that easy...

-Mike

 

My OEM charger = Fastest.
My generic spare charger I use at work = slower.
My car charger (Alltel branded) = slower, about the same as the 2nd charger.

 

They all seem quick to me, I plug my phone into my USB on my puter as soon as I get to work.. by the time lunch hits its fully charged.. I keep it on the charger all day pretty much unless im in a meeting..

phone doesnt charge at all when I get home..

 

YES, these do charge at different rates due to the fact that your car and your laptop dont output the same charge and dont amplify at the same charge as well if that makes sense..