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Help Weird battery life depending on how it's charged -wall or USB

htmlcssguru

Well-Known Member
Jun 28, 2010
107
19
We charge our EVO's (2 of them) each night using the wall plug and, of course, the light is green when we wake up. However, when we unplug them from the wall the battery charge percentage drops from 100% to about 92% within a few minutes without doing a thing. Now, at that time if I put it back on the charger but this time plugged into the USB on my computer it charges back to the 100% and then takes a long time to trickle down to the 92% (seriously, like 90 minutes including some usage in there).

I know there's some differences in the 2 charging methods. The wall charger charges much faster. But, it appears to be giving a false sense of a complete charge. The USB takes much longer (almost like a trickle charge) but seems to last longer.

Anyone else experiencing this? Have an answer? Solution?
 
I think that this happens to my phone as well. Yesterday it was plugged into the computer for a few hours and the battery lasted FOREVER, well not literally...But the battery percentage just decreased incredibly slow; it was amazing. Last night I charged it via AC adapter and bam, the battery dropped pretty quickly (from 70-30% in less than an hour).

I only noticed it yesterday, but I'll be testing it out more because if charging through the computer really helps this much, then it'll be my charging source.
 
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I think that this happens to my phone as well. Yesterday it was plugged into the computer for a few hours and the battery lasted FOREVER, well not literally...But the battery percentage just decreased incredibly slow; it was amazing. Last night I charged it via AC adapter and bam, the battery dropped pretty quickly (from 70-30% in less than an hour).

I only noticed it yesterday, but I'll be testing it out more because if charging through the computer really helps this much, then it'll be my charging source.

Thanks for your story. I'm interested to hear more people's experiences with this. The USB appears to be more of a trickle type charging process while the wall plug is like a gang bang of electricity.
 
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while i do think the usb method makes the phone hold a charge a little better, i think it has to do more with the phone being left on the charger overnight (and running off the phones power when it gets to 100%, explaining the quick drop to 92%). but when you charged it via usb, sounds like you were taking it off right away as it hit 100%, so it had no time to run off the battery.
 
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while i do think the usb method makes the phone hold a charge a little better, i think it has to do more with the phone being left on the charger overnight (and running off the phones power when it gets to 100%, explaining the quick drop to 92%). but when you charged it via usb, sounds like you were taking it off right away as it hit 100%, so it had no time to run off the battery.


I used the stock charger which charges at one amp for the first few weeks. Battery life sucked. I bought a second charger on amazon so I could have one at work. I started using this one at night:

Amazon.com: Belkin Mini Surge Protector Dual USB Charger: Electronics

and blam! Night and day difference! It charges at one half amp which will charge the battery slower, but it sure seems to be more complete.

Better yet, I had ordered Seidios extra battery and charger, and now I'm swapping batteries in the morning and getting 24hours use out of them...the Seidio charger also charges at .5 Amps - Something to think about
 
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while i do think the usb method makes the phone hold a charge a little better, i think it has to do more with the phone being left on the charger overnight (and running off the phones power when it gets to 100%, explaining the quick drop to 92%). but when you charged it via usb, sounds like you were taking it off right away as it hit 100%, so it had no time to run off the battery.

That actually makes perfect sense. Is that a fact? The phone stops charging and working off its own power when it reaches 100%?
 
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The phone manual says that charging via usb initiates a trickle charge but using the adapter is a faster and more powerful method. It could just be that your battery needs to be calibrated to give you a more accurate reading. I personally have not experienced any sudden drop in battery life after taking it off the charger. But I'll compare battery life from a usb charge vs an adapter charge to see how it is.
 
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I totally agree with the posters who have said that is due to the LENGTH of time it is on a charger. I always charge mine from a wall outlet, so I don't think it has much to do with wall outlet vs usb. I have quit leaving it on charging through the night, because once off the charger it drops like a rock. Bottom line...I always take it off the charger as quickly as possibly (say within an hour at most) after it shows green. I have very good battery life and am happy with it.
 
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