Wallplug vs USB

[plugnpl4y]

It seems that when I charge my phone slower via USB it will hold a charge for a longer period of time when compared to charging more quickly via the wall outlet.

To quantify a longer period of time: a typical wall outlet charge will deplete to 20% by the end of a normal week day (about 15 hours). A USB charge will last me over 24 hours on the same week day and then some (about 28 hours).

Has anyone experienced this? I have a friend with a Droid who has tested my theory and agrees. We thought perhaps the slower charge is more efficient and less of a strain on the battery.

 

[CarnageZ28]

You are not alone ...

I also noticed this. It def. gets better battery life from a USB charge for some reason.

My computer is literally 3" from my bed though so charging there, and using the phone for an alarm is just convenient.

 

[TheSultan]

That's interesting, I've never done this test. What about a USB port that plugs right in to an AC outlet??

 

[mj_b90]

That's interesting, I've never done this test. What about a USB port that plugs right in to an AC outlet??

Uh... that's exactly what our wall adapter is

I've never noticed holding a longer charge on the computer as opposed to outlet. It does take quite a bit longer to charge while on the computer though, I think.

 

[TheSultan]

Uh... that's exactly what our wall adapter is

I've never noticed holding a longer charge on the computer as opposed to outlet. It does take quite a bit longer to charge while on the computer though, I think.

lol I deserve a good smack. I confess, I don't use it. I use a hard-wired AC adapter that originally came from my Blackberry Curve 8330.

The USB cable that came with the AC plug sits in my car.

 

[xjken]

I believe this is true (unless it's just in my head). The USB "trickle" charges the phone, vs. the wall outlet being a quick charge.

I was big into RC cars and the battery charger had the option for trickle or fast. The trickle charge would always make the batteries last longer than a quick charged battery.

 

[SlickRick]

Perhaps the computer is like the trickle charger, I gotta try it. Also, should we limit using the car charger to .5 hours like my other cell phones? I know the car charger charges faster but the charge may not last long.

 

[Kevkelsar]

I have experienced the exact opposite. My computer charges don't seem to last as long as my wall charges.

 

[LexusBrian400]

This is a known fact for all batteries. The slower you charge, the less heat produced, and the easier it is on the cells. Ask any mechanic Kind of the same principles as fast charging a car battery. Not a good idea, produces lots of heat, but it'll work. Trickle is always better.

 

[VonKannick]

I think I read in the users manual available online that the charge rate from USB is something like 450mA and from the AC adapter is about double that. Someone told me though that LiIon batteries don't too much care how you charge them, but I still prefer the slower charge, just to be safe.

 

[LexusBrian400]

Someone told me though that LiIon batteries don't too much care how you charge them, but I still prefer the slower charge, just to be safe.

Yes that is true that they are better at handling the "memory" problem that non-Li-ion batteries have, but as a general rule, slower charging amperages are usually better no matter what type of battery.

 

[plugnpl4y]

Awesome! Good info here. It feels good to know I'm not crazy...

 

[DocTauri]

According to what I have been able to find on the web, a standard USB port is 5v/500mA, whereas the charger that comes with the Eris is 5v/1A (1000mA). I'm no electrical guy, but I would guess this means that the USB port should charge about half as fast.

 

[truelove79]

According to what I have been able to find on the web, a standard USB port is 5v/500mA, whereas the charger that comes with the Eris is 5v/1A (1000mA). I'm no electrical guy, but I would guess this means that the USB port should charge about half as fast.

That is correct.