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Help Battery level drops 30-40% immediately after removal from charger

Brocktune

Lurker
Oct 2, 2012
5
0
I've read some similar threads but I haven't been able to piece together what is happening with my phone.

This started last Thursday. I've had the S3 for several months and have gotten into a routine of putting it on charge overnight (while still on.) Thursday morning when I got to work I noticed the battery indicator was already down to 60%. Normally this early in the morning it is still in the high 90s. I brushed it off and thought maybe I forgot to charge it the night before.

Friday I noticed that as soon as I disconnected the charger, on which the battery level was showing 100% charged, it instantly dropped to 69%.

Saturday, Sunday and Monday the phone charged normally overnight.

Tuesday morning - battery level is showing 100% while connected to charger, dropped instantly to 58% after disconnected. I quickly went into the settings to what the battery stats indicated. When I went back to the home screen the battery showed 100% again. However by the time I made it to work 1 hour later, the indicator was already down to 51%.

Do I have a bad battery, does it need calibrated? Any ideas?

Thanks.
 
Update:

Stopped at the Verizon store after work. They said they needed to recreate the problem by testing how much charge the battery would take. The total process takes an hour so I declined.

Called the Verizon Warranty Center and the tech instructed me to turn the phone off to charge it overnight. This worked (battery fully charged and working normally) but it's not an acceptable long term solution for me.

My suspicion now is that due to the poor signal strength where I live (the suburbs but apparent Verizon dead zone) the wall charger simply can't overcome the phone's amped-up call standby power consumption.

I am going to do some more investigation when I get home. From what I have read the wall charger is rated for 1A output, however due to cheap construction and cable losses the actual output at the phone could be 0.5A or 0.6A. I also read somewhere that the S3 has a circuit that limits incoming current to 0.9 Amps to avoid battery damage. I am thinking that a better wall adapter and cable might provide more current and give me a full charge overnight.

This still does not explain why the phone says 100% and then instantly drops to 60% when unplugged.
 
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boy you learn something new everyday

I did a search on this and this is what I found

Simple Guidelines for Charging Lithium-based Batteries

A portable device should be turned off while charging. This allows the battery to reach the threshold voltage unhindered and reflects the correct saturation current responsible to terminate the charge. A parasitic load confuses the charger.

Charge at a moderate temperature. Do not charge below freezing.

Lithium-ion does not need to be fully charged; a partial charge is better.

Chargers use different methods for
 
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You're also not supposed to charge a battery overnight from what I've heard that damages the battery.

I always set an alarm to wake up at 2:00am to pull my phone off the charger. Then I wake up again at 5:30am to put it back on the charger, since it has had a parasitic loss during those 3.5 hours. Then when I wake up at 7:00am I am ready to take it off again.

This way I ensure that my battery isn't being damaged, and I am not taking away 2 days worth of its total life over the next 3 years, even though I'll probably have a new phone in 1.5 years, and also even though I could buy a replacement battery on Ebay at that point for $10 or so.

Now where is the icon for sarcasm for me to add to this post.......:D
 
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I always set an alarm to wake up at 2:00am to pull my phone off the charger. Then I wake up again at 5:30am to put it back on the charger, since it has had a parasitic loss during those 3.5 hours. Then when I wake up at 7:00am I am ready to take it off again.

This way I ensure that my battery isn't being damaged, and I am not taking away 2 days worth of its total life over the next 3 years, even though I'll probably have a new phone in 1.5 years, and also even though I could buy a replacement battery on Ebay at that point for $10 or so.

Now where is the icon for sarcasm for me to add to this post.......:D

You spread urban legends and damage your sleep time by waking up a few times during the night. I keep my phone one the charger for the whole night and can assure you it does not get damaged. Leave it one night and you will see, that it stops charging when full
 
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Update: After several weeks of trying things, here is what I found...

1st idea was to turn off 4G in hopes that the phone would not drain the battery as it was charging. I didn't have high hopes for this but it was the easiest thing to try. Worked for a few days and then the issue happened again.

In the meantime I installed the Battery Monitor Widget to see what exactly was going on. What appears to happen is that the battery attempts to charge but does so very slowly. After about an hour of only going from 62% to 69%, the battery all of a sudden jumps to 100%. It must be something that is programmed into the phone. Maybe they figure if you see it is at 100% you will unplug it and when when you plug it back in it will be on a better charger.

2nd idea was a better charge cable. I picked up a 3ft shielded cable from Monoprice and have not had the false charge issue since I have been using it. It provides a noticably faster charge than the cable included with the phone.

Problem is solved for now.:)
 
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