This is why your battery drops 10-15% in the first 20 minutes.

**Jesse** · 06-17-2010, 03:53 AM

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.

Workarounds?

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 6-18-10

So 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.

**fastlife2010** · 06-17-2010, 05:05 AM

Originally Posted by Jesse

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.

Workarounds?

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.

Interesting. Will have to try.

**ap3604** · 06-17-2010, 05:18 AM

Originally Posted by Jesse

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.

Workarounds?

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.

Wow =)

Thanks for the information. This answer's alot of questions if this works. Keep up the great information brotha' =)

**Qubix** · 06-17-2010, 05:44 AM

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

**Gekko** · 06-17-2010, 05:54 AM

>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.

**Qubix** · 06-17-2010, 06:12 AM

Its not the widgets that are reporting it incorrectly. They get their information from the phone sensors. Spare Parts shows hidden information that the phone already gathers and Battery Indicator matches it precisely.

**Gekko** · 06-17-2010, 06:25 AM

Originally Posted by Qubix

Its not the widgets that are reporting it incorrectly. They get their information from the phone sensors. Spare Parts shows hidden information that the phone already gathers and Battery Indicator matches it precisely.

yes i agree but my point is though that the widgets parse the battery information down to each (wrong) %. since this % is wrong, i'll go with the more blunt indicator of the default status bar which is a smoother and thus more accurate indication of battery life because it's not parsed and sliced and diced as much as showing a numeric %. numeric % is great when it's accurate. if it's not - it does more harm than good.

**drnez** · 06-17-2010, 06:31 AM

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.

**Gekko** · 06-17-2010, 06:34 AM

read my post again.

**Qubix** · 06-17-2010, 06:46 AM

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.

**2CupsWithString** · 06-17-2010, 06:47 AM

Originally Posted by Gekko

>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.

I'm right there with this as well, I just use the indicator at the top of the screen. The only time I think about the battery is when I read these threads.

**scott_0** · 06-17-2010, 06:50 AM

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

**drnez** · 06-17-2010, 06:50 AM

Originally Posted by Gekko

read my post again.

I did, and I stand by what I wrote.

The numbers coming off the sensor are (most likely) a percentage anyways. There is no "slicing and dicing" as you call it.

EDIT: Heres the applicable API calls

I can imagine any battery monitoring widget (including the default one) will just make a graph that sets the max to "EXTRA_SCALE" and the current level to "EXTRA_LEVEL". Its a percentage no matter how you look at it.

**2CupsWithString** · 06-17-2010, 06:51 AM

Originally Posted by scott_0

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

Now that is very interesting....

**Qubix** · 06-17-2010, 06:54 AM

Originally Posted by scott_0

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

Scott,

I am very interested in this, can you link exactly what you got?

Edit - is this what you have?
http://store.androidcentral.com/seid.../8A83A6730.htm

**scott_0** · 06-17-2010, 06:58 AM

^^yes, thats the charger I got

**Gekko** · 06-17-2010, 07:03 AM

Originally Posted by drnez

I did, and I stand by what I wrote.......

you keep missing my point. it's about perception. think about it.

**2CupsWithString** · 06-17-2010, 07:09 AM

Originally Posted by scott_0

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

I wonder if the EVO is using too much juice being itself so it can't ever really charge the battery 100%?

**Qubix** · 06-17-2010, 07:11 AM

Originally Posted by thefredelement

I wonder if the EVO is using too much juice being itself so it can't ever really charge the battery 100%?

In 6 hours, my phone consumed 3% battery. The phone really doesn't consume that much power when in standby.

**Mr. Berry** · 06-17-2010, 07:52 AM

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

**dfine1966** · 06-17-2010, 08:00 AM

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?

**Eazy123** · 06-17-2010, 08:05 AM

Originally Posted by Gekko

>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.

I know that my battery widget (which I paid $1 for) will be at, say 76%. I can literally watch it jump to 73%, for example. So I understand what you mean. I'm using Battery Time, btw.

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.

**bigblue4ever** · 06-17-2010, 08:20 AM

Originally Posted by Gekko

>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.

I've done the same..

**RayStinkle** · 06-17-2010, 08:33 AM

Yeah I don't know if I agree with this thread, cause the nexus one does in fact trickle charge. I would just assume the evo does as well. But who knows.

It also doesn't have that problem losing charge in the first 20 minutes.

**AngryCPA** · 06-17-2010, 10:03 AM

I usually top off the battery on the car charger on the way to work each morning and I have noticed a more consistent drain throughout the day after doing this.