- 58 Posts
This is why your battery drops 10-15% in the first 20 minutes.
Plain and simple: When the Evo is fully charged, it begins running off its battery until you plug it back in. It DOES NOT trickle charge whatsoever after it reaches 100%. When you're using your Evo on the charger, and it's showing full 100% charge, it is running off the battery, not the AC plug. And then when you unplug it, well, we all know what happens next. The battery meter drops insanely fast to the actual charge of the battery, which could be very low, depending on how long it's been sitting idle at 100% on your charger.
So all those times you've charged your Evo overnight, only to take it to work the next day and be at 80% within an hour? Your Evo was running off its battery for what I'm guessing was most of the night. It takes my Evo about an hour to two hours to fully charge back to 100%. Let's say you put your Evo on the charger at 11PM, it'll reach full charge by 1AM at the latest, and then run off its battery until whenever you take it off the charger in the morning.
1) Turn your Evo off while it's charging.
2) If you must leave it on for an alarm clock, put it in airplane mode and end all CPU intensive tasks to minimize battery drain.
3) When you wake up, unplug it for 10-20 minutes (still experimenting with this number), and then plug it back in to top it off. Once it reaches 100%, take it off the charger, and go about your day.
Try it out for yourself. When your Evo is 100% charged, take it off the charger immediately, and I highly doubt you will lose the 10%-15% within minutes. Please share your findings.
UPDATED 6-18-10So to help prove my theory, I've plugged my Evo into a Kill A Watt, and charged it to 100%. For those who don't know what a Kill A Watt is, it's a device you plug into your wall, and then plug your electronics into it, and it will tell you exactly how much electricity they're drawing. Coupled with the Battery Indicator app, I took readings on how much electricity my Evo was drawing as it charged.
I started charging at 78%, and it was drawing 0.08 amps until it reached 90%. At 90%, it began drawing less and less, until around 50%, at which point it was drawing only 0.04 amps. It stayed steady at 0.04 amps until it reached 100%. Soon after Battery Indicator was reporting a 100% charge, the Kill A Watt also reported a draw of 0.00. Meaning the Evo was not drawing any electricity whatsoever, indicating that it was in fact running off its battery. Even when I turned the screen on, maxed out the brightness, and ran Linpack, the Kill A Watt reported no electrical draw.
I kept my Evo plugged in for 15 more minutes, all while Battery Indicator reported a 100% charge, however, the Kill A Watt remained at a dead 0.00 draw. This doesn't necessarily mean that the Evo doesn't trickle charge, but it does mean it runs off its battery once it reaches a 100% charge. I have a feeling once the battery drops to a certain percentage (although still displaying a 100% charge), it will draw electricity until it reaches 100% again.
Still a bit more testing to do. Will be back with results.
Last edited by Jesse; 06-18-2010 at 05:45 PM.
- 06-17-2010, 05:05 AM #2
- 06-17-2010, 05:18 AM #3
- 06-17-2010, 05:44 AM #4
I cannot disagree with you more.
I charged it to 100%, watching the LED go from orange to green, and took it off the charger. Dropped 6% in the first few minutes and I was just watching it, not doing anything remotely power consuming on the phone. It dropped to 88% after 10 minutes total. Its not due to anything running in the background because I do not run any task killers and did not reboot the phone and continued to use it for an additional 43 hours... (I can provide screenshot of my JuicePlotter if you would like) from late Friday night to late Sunday night.
When I went to bed last night it was at 47% and woke up 6 hours later it was at 44%. My phone is currently at 26 hours without being charged and at 34%. In comparison my friend has Good For Enterprise (GFE) which constantly keeps his phone awake and he can't make it half a day without having to charge it.
Some of the characteristics I am noticing with this phone that are abnormal. Usually when charging a battery and it approaches maximum capacity, charging will slow down, each % becomes longer and longer. With the EVO it seems to be very linear, no slow down. Example of normal charging: charging from 80% to 90% takes less time than going from 90% to 100%. Charged my phone to 100% (green LED) and used it to take the battery level to 90%. Put it back on the charger and it quickly reached 100% (green LED) in maybe 10 minutes.
It seems as if:
A) Battery charging circuitry isn't charging the battery to full capacity
B) Battery capacity indicator circuitry isn't reporting proper battery capacity
- 06-17-2010, 05:54 AM #5
>B) Battery capacity indicator circuitry isn't reporting proper battery capacity
personally - i think this is the case - especially with the widgets. this is why i've ditched the battery widgets with %. hey are not correct and i don't need to stress over every misreported %. i use the stock default battery bar and am a lot less stressed about battery life now.
- 06-17-2010, 06:12 AM #6
- 06-17-2010, 06:25 AM #7
- 06-17-2010, 06:31 AM #8
- 47 Posts
What makes you think that the stock battery indicator reads any different information than one that shows a percentage? Its all based off of the same sensor data, just displayed differently. If the phone is reporting the incorrect battery capacity, all the battery widgets along with the stock one will be incorrect.
- 06-17-2010, 06:34 AM #9
- 06-17-2010, 06:46 AM #10
When I say the circuitry, I mean the actual hardware that is directly monitoring the battery itself, not the software running on the phone.
I am more inclined to believe its the first one. I would like to know if the same problem with battery drop exists on other HTC phones. Since the batteries are interchangable with other HTC phones I would like to charge my battery in one of those devices or use a battery that was charged in one in my phone and see if I experience the same phenomenon.
Food for thought.
Also I wonder if a dedicated battery charger works any differently for these batteries / phones. Don't know if I would want to remove my battery every day or couple days and have to pop that back cover off, it already looks fragile enough as it is.
- 06-17-2010, 06:47 AM #11
- 06-17-2010, 06:50 AM #12
I turn my phone off at night while charging it, but it still drops almost as soon as I power it up. I have noticed when I charge my extra battery through my Seidio stand alone desk top charger that the battery stays at 100% for 1hr or so before dropping
- 06-17-2010, 06:50 AM #13
- 47 Posts
- 06-17-2010, 06:51 AM #14
- 06-17-2010, 06:54 AM #15
- 06-17-2010, 06:58 AM #16
- 06-17-2010, 07:03 AM #17
- 06-17-2010, 07:09 AM #18
- 06-17-2010, 07:11 AM #19
- 06-17-2010, 07:52 AM #20
here is a couch android expert opinion: it's a huge phone steroids, it needs massive juice supply. Battery industry needs to catch up. end of story.
Ferrari has huge engine = use more juice
Hummer huge = more juice
mini cooper tiny = less juice
now let my flaming begin
- 06-17-2010, 08:00 AM #21
I was having similar questions about charging and why power drops so quickly. I have noticed if I charge the phone in the off mode, and the green light goes on, I unplug it and shut it off for the night. When I turn it on in the morning, it is not 100%. It is usually anywhere's from 99% to 96%, never 100%. Now when I charge it off first and it hits green, I unplug the EVO, turn it on, plug the charger in and wait till it gets to 100% again, and then shut it off, and when I turn it off, it is 100%. This makes no sense to me at all. I was going to ask the question of which is the best way to charge the phone, ON or OFF? I have seen just the opposite effect with it being On vs Off. It seems to stay at 100% more being ON, not OFF. But it does seem to work better charging it from the off first(quicker) than turning it on to top it off. Is every EVO different, are the batteries (Stock) acting differently for everyone.
What is the best way to charge it and get 100% in the morning?
- 06-17-2010, 08:05 AM #22
But after a night of charging, I'm usually in the mid 90s by the time I get to work, so it's not that bad.
- 06-17-2010, 08:20 AM #23
- 06-17-2010, 08:33 AM #24
- 06-17-2010, 10:03 AM #25