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.
Er... Point of note, mine does it even if I pull it off the charger right when it turns green.
Post some technical schematic or other type of proof that shows that this circuitry isn't available in the EVO. That will prove beyond a doubt if what your saying is true.
That being said, only a group of the most retarded electrical engineers would design a charging system as you've described. It is INSANELY easy to build Li-Polymer charging circuitry that does the following (and it pretty much has to do these):
1. Detects battery temperature, and disables charging as a protective measure. In an emergency case it should shut off the device it's powering to allow the battery to cool down. This is a design requirement, or else your house burns down as you dump water on a Lithium fire thinking it's going to put it out. If you have a HERO, you can easily test this. Running the wireless tethering, GPS/Navigation, and Music with the screen running heats up the phone a ton. You'll notice the status light blink green once, then red a couple of times. This means that it's plugged in but not charging. Cool the phone down and it turns solid red again (charging).
2. Disable charging cycle when battery reaches a certain voltage. VERY SIMPLE voltage detection circuitry! The designer can of course adjust a gap to have charging turn back on when it dips below a certain voltage. Usually since this circuitry can be made with a decent amount of precision, that "turn back on" voltage ends up being roughly when the battery discharges to maybe 99.5%. That's just a guess, I admit but there's no harm in having the circuit switch on and off, even if it's often.
There are also a few other circuits that prevent the cell from blowing up in your pocket, like a current sensor to prevent an overcurrent. There's also some stuff that prevents you from being able to discharge the cell below it's avalanche voltage. In case you don't know what that is, when a Li-Ion battery discharges to a certain voltage, it avalanches to 0 (quickly falls). If it hits that point, you've pretty much ruined the battery and it will never charge the same again.
Anyway, this is stuff they taught and had design labs on back in college. While I have no actual proof that the phone wasn't designed as the OP describes, I find it highly unlikely. If this is the behavior that the circuitry exhibits, I would find it easier to believe that it's a design flaw, probably because some idiot didn't compile the correct bill of materials.
I haven't got any schematics or any sort of technical information on the subject. All I know is, it works wonders for me. When I take my Evo off the charger in the morning, it literally drops to ~90% within minutes. Once it does that, if I place it back on the charger for ~20 minutes, it charges back to 100% and stays there for 45 minutes to an hour.
I'd urge anybody who is noticing the immediate 10% to 15% drop in battery to give this a shot.
I would turn it off while I'm charging it overnight, but I use it as my alarm clock
Me Too
I am seeing the exact same behavior as the OP. This is really lame. Because of this, most people will end up losing 10% of their battery every day. Pretty lame.
I charge my phone overnight every night. Never noticed a problem and I just checked my battery and its at 88% and has been off the charger for 2.5hours so I'm not seeing the rapid discharge issue some people are seeing.
I don't think so man, I leave my screen on full brightness while it's charging, and if what you said was true it would go dead on the charger.
I think it's more likely the cells haven’t charged equally, so you get a big initial drop.
Grims said:
I don't think so man, I leave my screen on full brightness while it's charging, and if what you said was true it would go dead on the charger.
I think it's more likely the cells haven’t charged equally, so you get a big initial drop.
Click to expand...
Click to collapse
I'm beginning to think that once the battery reaches 100% full, it runs off the battery until it reaches some arbitrary percentage. At which point it starts charging until it reaches 100% again, and then continues this cycle.
I'm testing a few other things right now. Part of me is convinced it reports 100% charge when it's actually below that level.
Krynj said:
I haven't got any schematics or any sort of technical information on the subject. All I know is, it works wonders for me. When I take my Evo off the charger in the morning, it literally drops to ~90% within minutes. Once it does that, if I place it back on the charger for ~20 minutes, it charges back to 100% and stays there for 45 minutes to an hour.
I'd urge anybody who is noticing the immediate 10% to 15% drop in battery to give this a shot.
Click to expand...
Click to collapse
I'll try this out to see if I can get the same kind of behavior. I guess I honestly haven't looked to see if the phone drops 10-15% after pulling it off.
Krynj said:
I'm beginning to think that once the battery reaches 100% full, it runs off the battery until it reaches some arbitrary percentage. At which point it starts charging until it reaches 100% again, and then continues this cycle.
I'm testing a few other things right now. Part of me is convinced it reports 100% charge when it's actually below that level.
Click to expand...
Click to collapse
This is what should be happening I believe, but I'd be surprised if it was set to such a huge swing like 10-15%
Grims said:
I don't think so man, I leave my screen on full brightness while it's charging, and if what you said was true it would go dead on the charger.
I think it's more likely the cells haven’t charged equally, so you get a big initial drop.
Click to expand...
Click to collapse
This is an interesting theory. I do know that when you have multiple Li-Ion cells in a battery pack, if they discharge unevenly, you have to go off of the lowest charged cell. Again, if a cell were to drop below the avalanche voltage, you'd ruin the pack all together. On the other hand, the circuitry should let ALL cells charge to 100% so it's even again. Maybe they screwed this up, that design isn't so easy! Perhaps it detects one cell as 100% and shuts off the charge. Therefore, one could surmise that if you started with an unevenly charged battery pack, you'd have an immediate decrease in charge to the rating of the lowest charged cell. The good news (maybe) is that this is sometimes implemented with software. That means that HTC could release a bug fix for this, or if we have a savvy dev, they could try to fix it. We just need to prove the theory though.
This is all just a guess, keep that in mind. If I notice something like this with my phone today, maybe I can tear apart the battery and measure the voltage on each cell (if it even has multiple cells). I have a spare, so maybe I'd be up for this. Krynj (or anyone), if you have the HTC Hero, try charging your battery pack with it, see if it exhibits the same behavior on the Hero itself. If it doesn't, then try putting it back into the EVO and see if after a night of charging, it still drops 10-15% after disconnecting it from the AC.
The reason why the battery dies so fast has something to do with the memory card. Charge your phone and take the SD card out and watch it stay at 100% for a long as time. Then do it again with the SD card in and watch it dip down fast.
Apple laptops don't charge unless battery is below 90%. If you plug in the AC and the battery is above 90%, it will just run off AC power but I don't think the battery drains any then.
My battery life has been less than stellar, but I didn't notice it dropping 10-15% instantly off the charger. I did notice that it'd drop about 10% after driving to work with xiialive streaming, which was unusual to me. The battery would start running out after about 9 hours at work. I'd be in the yellow by the time I got home, and the battery would be complaining for a charge in the evening. So that's roughly 12 hours I would be getting out of the phone after normal use.
Since I'm suspecting an issue with the charging circuitry, I just recently tried charging my battery with the Hero. After it was fully charged, I put it back into my EVO last night and haven't charged it since. It's been running 13 hours, and is still nearly full green. The charge is at about 70%. I've been trying to graph the discharge all day too. It only dropped to 87% over night, dropped to 80% when I drove to work (xiialive), and then down to 74% after I spent some time setting up icons and modifying my home screen. This is...hands down a butt ton better than the past week.
I'm not using 4G.
WiFi is off.
3G is on.
GPS is on.
Not running a live wallpaper.
Sync is running at default settings.
Widgets that could be updating constantly:
I have the Clock/Weather HTC widget running.
I have the Dictionary.com "word of the day" widget.
I have the Friendstream Widget running.
Craigslist Craignotifica app is running, set to notify me with search results.
The results are inconclusive though. Yesterday, I wiped and re-flashed DamageControl 3.2.x from scratch (backed up all apps with Ti-Backup, this means Android Market won't be notifying me if there are app updates -grumble-). So, somewhere between re-flashing and also charging my battery with the Hero caused this turn around.
apollooff320 said:
The reason why the battery dies so fast has something to do with the memory card. Charge your phone and take the SD card out and watch it stay at 100% for a long as time. Then do it again with the SD card in and watch it dip down fast.
Click to expand...
Click to collapse
Interesting.....Will have to give a try. Will report back later.
I'm waiting for some definitive results with the "use another charging device or battery" method. It seems that the EVO just sucks at recharging the battery since people who have used another phone or a separate charger seem to report better results.
I leave my phone off at night and charge it - when I turn it on in the morning it still drops 5-10% in the first 20 minutes. But during the day it drops REALLY slow, so I still can get about 13-16 hours before 15% easily.
I have manual account sync, 3g only, wifi at home, usually gps is off, auto backlight settings for screen, and I don't run too many apps in the background, I just use them when I need them.
Has anybody found a solution to this? It's really starting to bother me. I've noticed that I don't seem to have the issue if I charge -> recovery -> wipe battery stats -> reboot. That kind of leads me to believe that something is inaccurate about the battery stats and the phone instead uses the actual raw value provided by the battery instead of whatever it is that it does with the battery stats.
I can tell you this, I bought two of the cheap battery chargers off of ebay and I have two OEM evo batteries. I don't even plug my phone in anymore. I get an hour of standby at 100% from those chargers and it falls instantly when charging from the phone. I just run them down then swap them out. I couldn't be happier and they are only like 10 bucks each with 2 batteries each.
Sent from my PC36100 using XDA App
jnewkirk10 said:
I can tell you this, I bought two of the cheap battery chargers off of ebay and I have two OEM evo batteries. I don't even plug my phone in anymore. I get an hour of standby at 100% from those chargers and it falls instantly when charging from the phone. I just run them down then swap them out. I couldn't be happier and they are only like 10 bucks each with 2 batteries each.
Sent from my PC36100 using XDA App
Click to expand...
Click to collapse
can you post a link or ebay or where ever u bought it from?
Try this I'm doing it from the phone
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=250641711190&ssPageName=STRK:MEWNX:IT#ht_1991wt_913
Sent from my PC36100 using XDA App
apollooff320 said:
The reason why the battery dies so fast has something to do with the memory card. Charge your phone and take the SD card out and watch it stay at 100% for a long as time. Then do it again with the SD card in and watch it dip down fast.
Click to expand...
Click to collapse
If you have apps on your sd card that are running then yes that could be the case. SD cards need power to work but I dont know how much they draw..
Hi guys,
Does anyone have any idea to this WEIRD issue I've had with my Desire Z?
Basically, my phone was working normally last night. I then put my phone on to charge as normal before I went to bed, and I left it on the bed. About 5-6 hours later (I had to get up early today...) I turned over and touched the back of the phone and woke up shocked, as the back of the phone BURNED me! I got very confused and looked at the phone. It was VERY hot to hold, and it was on 42% battery. I then took the battery out, and it was almost hot enough to burn me. I left the battery out of the phone until I got up properly and tried turning it back on, and it got very hot, very fast.
I figured it could be a problem with the 1800 mAh Mugen battery I was using, so I decided to put my old stock HTC battery in. I got the same problem.
It seems to have got slightly better now, but I can only really use the phone in 5-10 minute bursts now. When the phone has booted up the battery will report around 36 degrees. After 5-10 minutes it sails up to about 50 degrees before I turn it off. The battery also drops off fast between reboots, losing around 10% each time I reboot (however, it doesn't seem to drop that fast when I'm actually using the phone...).
I am rooted and using Cyanogen Mod 7, and I recently flashed to the 151 nightly. I tried flashing to some of the earlier nightlies I still had on the phone, but the issue is exactly the same.
I did have the phone in the bootloader for a while (volume down+trackball), and it didn't seem to overheat. However, when I tried charging the phone with the device off the battery seemed to get VERY hot (way more hot than normal).
Luckily I can still back up anything I need to back up, and I am going to start doing wipes soon (assuming the phone doesn't overheat while wiping, which worries me!), but I am very confused!
I'm thinking that some sort of short circuit has happened, or something?
Does anyone have any ideas? If it's a definite hardware problem I can get a replacement fairly easily, but I do love my Z, so it's the last thing I want to do...
Very lucky my dad has a Samsung Galaxy Tab I can borrow as a phone for now. It will be fun for a day or two having a 7" tablet as a phone, but it will get old fast!
Thanks a lot, all!
Edit: I think it's had it. I tried using another charger and another USB cable and leaving it charge for a bit. When I came back after about 15 mins, again the phone was very hot, and the indicator light was flashing green and orange. When I tried to boot the phone it was dead. When I plugged it back in the indicator light would flash orange on and off for a while, then start blinking weirdly. Lucky my mugen battery still has about 15% charge... xD
http://support.t-mobile.com/thread/2710?start=75&tstart=0
It's *possibly* this problem.
My phone does the same thing, gets SUPER hot when charging, and has extremely short battery life.
Mine's not charging at all now, so I'm not even sure what to do at all :/
If I use the phone a lil and my Mugen battery dies, I won't be able to turn it on at all, so I'm not sure whether to start wiping and stuff now...
General consensus is to not leave the phone to charge overnight?
not with today's technology. all batteries (atleast good ones) have an internal circuit that keeps the battery from over charging. it also provides a method to maintain the charge by letting the phone drain some battery over the night by 5-10% then performing a trickle charge to slowly (very slowly) recharge the battery.
I've been leaving my stuff charging overnight for over a decade. It's not as bad as you think it is.
Apparently I am in the minority, but my VZW LG G2 (Stock) was affected the the slow charging battery drain issue after upgrading to Lollipop.
It's crazy just how slowly the phone would charge and drain. After the update my phone was constantly attached to a charger. It couldn't make it to mid-day even with little use. It would take hours to gain just 20-30% charge.
After months of complaining I finally "downgraded" to KitKat. The difference is amazing. I can easily make it through a full day with moderate use and I can almost fully charge the phone after about an hour. It's great.
Has anyone had this problem and figured out a cause or solution? I've always been stock, but has a custom lollipop ROM worked better? At the moment I think I'm going to wait until there's another update (hopefully) before upgrading.
I am having same problem as yours, the battery problems are on the rise with Lollipop update. Sometimes I wish I shouldnt have upgraded. But anyhow, I solved my problem by using a good charger, more details you can read on this page: http://www.techkhoji.com/slow-battery-charge-android-iphone-samsung/
Argh! After weeks of deferring the daily lollipop update request I was half asleep on morning and accidentally started the update. I couldn't stop it once it started.
My phone was just about dead when the update finished and I let it fully charge. To my surprise it charged surprisingly fast. After it was fully charged (and unplugged) the phone stayed at 100% for about 20 minutes of continuous use before it dropped to 99%. I was again surprised that the phone held a charge (no charging) all day with moderate use. In the evening it stayed at 0% for a while before it finally died. I suspect the phone was calibrating the battery during this initial use.
I thought perhaps the problem was solved, but a day later, the phone is back to charging painfully slow.
I actually measured the charging current, it's not just my imagination! I have a USB Meter and when the phone was on kikkat and for the first day on lollipop it would consistently charge between 1.5A and 1.8A. Now, it will only charge at 0.46A. I'm using the same chargers and charging cables.
What could have changed? Is there a way to reset whatever battery calibration may have occurred?
I got a t330nu and have had some wierd things happen with the battery that I've not experienced with other mobile electronics. First, one cold winter day (I live in the north were it snows alot) I was driving and my battery died, I accidentally left it in the car overnight and when I plugged it in the next day it was at like 87 percent. I unplugged it and it remained at 87 percent for maby 2 hours and then screen went black and it died. It still showed 87 percent untill it died. Plugged it I and charged it back up and everything was normal. I haven't wanted to try to replicate it cuz I don't want to have to replace the battery.
Next wierd thing is sometimes when I use an underpowered charger or my car charger, it shows the plugged in but not charging icon and it actually is charging, my battery says like 2 percent but it will last for hours. I don't like doing this but it has happened on occasion.
Has anyone else experienced this? Any thoughts on the freeze charging? Comments, questions are welcome. But don't hate lol.
Forgot to mention, I've had this for over a year and battery seems fine given the age. I can usually use it all day on a full charge depending on what I'm doing. But GPS kills it in like 3 or 4 hours and some other games and apps drain it stupid fast. Any tips on kernels or roms that help with battery life?
I dont think that leaving tablet to low temp fr 12 hrs or so wont damage it that much, i got my 7.0 version and walked to school at -27 celsius and it lost none % (walked like 15 mins)