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99% Battery Life

Ken7

Android Expert
Jun 11, 2011
855
212
I'm just curious if you guys notice the same thing. When I've fully charged the standard battery, it reads 99%, not 100%. If I unplug it just for a couple of seconds and then plug it back in, it will reach 100% in a short time.

But it never gets to 100% on one plug-in. It's not a big deal, my battery life is great regardless, but I'm just wondering if others have seen that.
 
Yea this is the only phone that's done that for me. Charges 6 hours (not from empty) at night, and sits at 99%. Unplug and plug back in and its fine. A bit annoying but ehh..

Oh, no custom kernels here...

I did observe this on the Rezound, too. I watched it charge and report 100% then it dropped down to 99%. It's like it cut the charging circuit off entirely. I didn't leave it plugged in to see if it would continue to drop down or trickle charge back up. I think this is normal, but someone more familiar with these new battery and charger circuitry may know for sure if it's normal or not.
 
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I have my phone completely stock, and I see this regularly. In fact, sometimes it only goes to 98%. I've even seen it drop from 99% to 98% while plugged in.

I'm using Battery Monitor Widget to look at the battery history. It reports % available, mA, and some others. I can see that it DID reach 100% while it was charging, then dropped back down. It looks like it charged to 100%, sat at 100 for about 30-45 min, then dropped to 99, then 6 hours later dropped to 98%.
 
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Sorry to bump an old thread, but it is linked from a sticky and still relevant and hasn't been resolved here. The stock kernel keeps the battery charger below 100% to preserve battery life. Actually stopping at 97% would have yielded the best life (meaning life span of the battery here, not uptime) but I'm sure more than one customer would have flooded Customer Support up with complaints. I haven't checked out the thread linked to above and don't know if this is their conclusion (will look after here) but having programmed low level device code for a long time I can almost assure you that this is intentional, or WAS intentional and was never meant to be released this way (as I THINK the update now has the percent going all the way to 100% now, unless you are on a custom kernel that allows you to set when to stop charging). Personally, I have mine set your stop at 97% for this very reason. Regardless, it seems to have been changed in 4.0.4 (could be wrong as I'm on AOSP). I can't see any other reason that would have caused this besides maybe a miscalculation in the kernel code. Take your pick :)
 
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