This is a defect I have observed all the way from Android 1.6 to Android 5.1.1, and I cannot understand how it can still be there without ever getting repaired.
The problem is that the battery indicator shows a positive number, for example, 8%, although the battery is actually at 1% and the phone will shut down any moment now.
This alone would be bad enough, but it gets worse. After the phone shuts down on its own, either due to an immediate, disorderly power cut or by performing an orderly Android shutdown, Android should have registered the obvious, namely that the battery is empty.
However, it does not. When I connect the charger and start Android, it still shows 8% charge. I have just tested this again three times in a row with at least one orderly shutdown on my latest phone, a OnePlus One running CyanogenMod 12.1, and it never went below 8%.
How can this be? How difficult is it to program that after a shutdown due to an empty battery and a restart one minute later the battery is indeed empty? It is not physically possible to charge a battery from 0 to 8% in a minute. It would explode if you tried.
Do the charging electronics not store and provide information at least about the very recent charging history? And can the phone not evaluate the battery voltage, which it measures? At least when there is no load on the battery for a little while, its voltage and its temperature allow to determine precisely whether the battery is empty. Why does the phone not do that?
Needless to say, this defect is damaging. To know how soon the phone is going to shut down is one of the most crucial bits of information for every phone user. To show the user 8% while already shutting down is beyond stupid, it is derisive.
I have something in my head that I call the idiot bells. They ring when I notice idiocy in my surroundings. And whenever I see the phenomenon described above, they ring loudly.
Can anyboy who really knows how Android and the charge electronics work explain what is happening? Or is it just the ordinary idiocy that we have to keep living with?
Do not suck nonsense replies from your fingers. If you don't know anything reliably and in detail, keep quiet.
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hi I've heard plenty of times that you should charge your phone once you get it or charge overnight..is this true in anyway? I always go straight to playing with my new phone and then charge once battery dies..any thoughts on this myth?
Hi. I have heard a few different things about this. I think there is a thread on here I read about it as well.
First is that it won't matter because batteries no longer need to have that memory thing.
Then there was one that said let it deplete, charge it and then when the light goes green unplug it and replug it in. The light will go red for a few more minutes and then green. That will set the battery.
Then I also read that you shouldn't charge it completely or let it completely deplete because that will lessen the charge over time
The last I heard is that (and this was under the discussion about extended batteries if I remember correctly) the batteries are made so that the battery meter tells us it is dead even though there is still a little bit of a charge on the battery that way it doesn't do anything bad to it.
So I really think it depends on who you listen to. I did the let it deplete and charge it thing once so far. I get decent battery life. I tested it and got 10 hours out of it with medium usage and I usually get more when I toggle off the 4g when not using it but haven't timed how long for that yet.
Hope that helps until someone who knows more specifics posts something.
jonathan413 said:
hi I've heard plenty of times that you should charge your phone once you get it or charge overnight..is this true in anyway? I always go straight to playing with my new phone and then charge once battery dies..any thoughts on this myth?
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I don't think it matters any more. I plugged mine in after I did initial setup and let it charge to green light, didn't do any special bump charging or charging while off. The battery is designed to be used as is, without any tricks. Always overcharging to 100% or completely draining to 0% is probably worse than just using it normally and plugging it in when you notice it's relatively low.
There's a battery log that Android keeps regarding voltage and reported capacity that it uses to adjust the percentage display that you see on your phone. This changes over time as it gets a better idea of how the battery discharges, so built into your phone is a mechanism to make sure the reported capacity is accurate. If it gets "off" a bit, like if you see a huge spike up or down in battery capacity after a reboot, it's just adjusting itself.
But, as you know, Android users love to control everything by themselves, and not leave anything to some process behind the scenes. Hence the clamor for root so we can install whatever we want. So some people like to trick this adjustment mechanism by force charging the phone to full when it's off, which gives the battery capacity adjustment mechanism a "true" full charge to base its reporting on. Also, I don't believe the kernels in stock ROMs will charge to what it believes a full 100% charge is, to protect the battery life. Bump charging kind of gets around that, if I understand the process correctly.
Also, I don't charge overnight (lack of outlets in bedroom) so I make sure it's topped off before I go to bed. Even if it's not, it can make it through the night just fine, since it's not being used. So that's not that much of an issue anyway.
TL; DR: Just use it, plug it in when you need to.
Hi,
I have been facing these two weird issues:
1. Sudden drop in battery percentage: I have found that this occurs only when i reboot my phone (not every time though). So when the phone restarts, the battery is down by 20-30% or sometimes even more. And its not a one time issue. I have seen it happen at least 3-4 times in the last 5 months.
2. Sometimes when I am not charging the phone, the battery % keeps increasing slowly. This has been happening lately since the time I have rooted and flashed my phone. 2-3 occurrences that i know. I don't recall seeing this when I was on stock. Just this morning I plugged my phone off the charger at 52% and I left for work. And right now at this moment when I am writing this, the phone is at 58% charge!!
Just FYI.. I calibrate the battery every time I flash a new ROM.
Thanks,
Sam
sammy.samsung said:
Hi,
I have been facing these two weird issues:
1. Sudden drop in battery percentage: I have found that this occurs only when i reboot my phone (not every time though). So when the phone restarts, the battery is down by 20-30% or sometimes even more. And its not a one time issue. I have seen it happen at least 3-4 times in the last 5 months.
2. Sometimes when I am not charging the phone, the battery % keeps increasing slowly. This has been happening lately since the time I have rooted and flashed my phone. 2-3 occurrences that i know. I don't recall seeing this when I was on stock. Just this morning I plugged my phone off the charger at 52% and I left for work. And right now at this moment when I am writing this, the phone is at 58% charge!!
Just FYI.. I calibrate the battery every time I flash a new ROM.
Thanks,
Sam
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Click to collapse
I think that Entropy can answer this better but I'll still give a try.
[Q] Why these sudden battery level drops after reboot?
[A] The sudden battery drops is a known 'issue'. It's not a bug, it's the way the fuel gauges are designed for i777.
[Q] How to avoid these sudden battery level drops?
[A] Try not to reboot while it's on battery if the battery level is <50%. In that case, if you need to, make sure that the phone is plugged in for charging and then do the reboot. That should prevent those random battery level drops.
[Q] Will using battery calibration apps help?
[A] No, the way the i777 fuel gauges are designed, there is no need of battery calibration apps. The best way to get accurate battery level readings is to allow the battery to go through full 100%->0% battery discharge cycles for atleast 2-3 times. After each full discharge remove the battery, keep it out for a minute or two and reinsert, recharge the phone.
PS: The weird battery charges that violate E=MC^2 law might have to do with your battery not having been through proper discharge cycles (and thus not having been properly calibrated) after flashing a new ROM.
@Mod These questions are asked many times, how about adding them to FAQs (not sure if that will help though )
@Entropy Please review this post.
Pretty close.
Calibration does nothing on our device - the fuel gauge is designed so that it will always converge towards truth instead of diverging. Also, the "wipe battery stats" method of "calibration" has been proven to do NOTHING on ANY device whatsoever - https://plus.google.com/105051985738280261832/posts/FV3LVtdVxPT - The "charge battery to full" and "discharge/recharge" battery are valid tactics on some devices, but NOT any Galaxy S or S II device (maybe the ****rocket and T989, but not the I9100 or I777.) - There's a slight chance this may change with ICS on the I9100/I777 but not likely.
The advantage of this is that it never needs funky calibration cycles other than "just wait"
The disadvantage is that the gauge will get thrown off in a few limited corner cases - and the "two" issues described are one widely documented one. The gauge gets confused and falseley reports low by heavily battery load immediately following a reset, and takes a few hours to converge back to normality (during which the estimate creeps upward, because it was lower than reality initially).
And yeah this should probably be in the FAQ. I'll work on submitting it this weekend.
Thanks guys..
So looks like the sudden battery drop issue can only be prevented but not fixed!
sammy.samsung said:
Thanks guys..
So looks like the sudden battery drop issue can only be prevented but not fixed!
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It's pretty much the characteristics of putting a battery under load and using voltage to dictate battery level. when you draw a lot of current from a battery you'll usually see the voltage level drop, more so as the battery is discharged. Booting up the phone consumes quite a bit of power, substantially more than the device at idle. So upon start up the device reads the voltage level to dictate battery level. Since the device is under a relatively high power draw, it sees a lower voltage than would be at idle. It in return thinks the battery is lower than it actually is, or would read under idle load. the battery level will actually creep back up slowly because it will read a higher voltage, than it did upon start up.
The only way i could think of to get a more accurate reading would be to delay the initial voltage reading/recording upon start up, or to use the last voltage reading to help dictate the battery level. But i have no idea if that's even possible, or if it would conflict with some sort of other operation.
I just don't get it!!!!!!!
I was playing multiplayer in bombsquad today morning wid my friend .My battery was @ 86% at that time
suddenly my battery came down to 15% then in the other moment it went to0% and mt phone got shut down. I plugged my phone in charge through the power bank and rebooted it and I saw my phone was @52 % I started using my phone and it again suddenly sut down this time without even a battery low message
it's been happening regularly wid my phone since then.
What could be the reason? And what can I do to make it right?
MY PHONE INFORMATION
MODEL:SAMSUNG GALAXY CORE GT I8262
ROM:USING STOCK ROM(ROOTED) (CWM RECOVERY INSTALLED)
avijeetpandey87 said:
MODEL:SAMSUNG GALAXY CORE GT I8262
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This is the wrong forum. Even though the thread is about a problem similar to yours, we don't know anything about your phone.
If you have a removable battery, you might try purchasing a new battery, but that's just a guess.
The forums for you phone are here.
I know for a fact that my battery level is incorrect. It's a 2500mAh battery, and yet after a couple minutes of heavy use, the battery level will drop to zero and the device will shut itself off.
Weirdly enough, I have this same issue with my MacBook, and I've figured out (at least on the MacBook) what the problem is: the machine isn't calculating the remaining time/percent correctly. If I don't use it to do power-instensive tasks, it will be fine up until the battery truly drains. But if I run, say, high-graphics video games, it will detect the battery's getting used very quickly, somewhere along the line it will freak out thinking that this battery drain is leaving it with seconds to spare, and will shut down. If I press the power button to start up, it won't, only displaying the 'out of battery' symbol on the screen. But, in actuality, there's usually about 30-50% battery left in there. How do I know? If I apply the charger for a bit, even for two seconds and then detaching, forcing the machine to recalculate the remaining battery, it will turn back on and have 30-50% left for me to use.
Here's the thing, though: with my phone, I usually don't have anywhere to charge it. So I'll unplug it in the morning to last me all day, hop on a bus to explore the city, forget about this issue and launch a graphics-intensive game, and then only realise what I've done four or five minutes later when it shuts down on me, thinking the battery's completely depleted.
So here's my question: How can I force the phone to ignore the battery level, and keep sucking juice from it whilst there's juice to be had? I know, I know, it shuts down for my own good, to make sure it has enough battery so that it can power back on again later. But right now, this usually-useful feature is rendering my phone virtually useless. Any advice?
Thanks.
My HDX 7" has developed a behavior such that when plugged into charger it shows 100%. But immediately after disconnecting the charger a low battery alert is seen and then it shuts down.
Sometimes (just after that happens) it can be immediately restarted, and the battery shows 100% when it boots, and it behaves normally (gradually discharges) for a while.
Then, again, suddenly the charge will drop from from, say, 87% to 0% instantly, and the machine issues a warning and shuts down.
So I think the battery is actually OK (because it can come back and behave normally for a period, powering the unit for a reasonable time-span, even though it has previously issued the low-battery warning), but there is some sort of bad connection associated with the 'low battery' sensing. .
(I -can- work around it by keeping it permanently on the charger.)
Unit is about 4 years old.
Thanks for any thoughts, and especially if anyone has also had this behavior and been able to correct it.
skyhawk64 said:
My HDX 7" has developed a behavior such that when plugged into charger it shows 100%. But immediately after disconnecting the charger a low battery alert is seen and then it shuts down.
Sometimes (just after that happens) it can be immediately restarted, and the battery shows 100% when it boots, and it behaves normally (gradually discharges) for a while.
Then, again, suddenly the charge will drop from from, say, 87% to 0% instantly, and the machine issues a warning and shuts down.
So I think the battery is actually OK (because it can come back and behave normally for a period, powering the unit for a reasonable time-span, even though it has previously issued the low-battery warning), but there is some sort of bad connection associated with the 'low battery' sensing. .
(I -can- work around it by keeping it permanently on the charger.)
Unit is about 4 years old.
Thanks for any thoughts, and especially if anyone has also had this behavior and been able to correct it.
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Sorry for bad news - textbook symptoms of a failing Li-Ion battery. Voltage momentarily collapses and reported charge level drops dramatically (often to zero). You may be able to nurse a few more good cycles from the pack but total failure is likely not far off. Replacements are getting hard to find; cracking open an HDX without shattering the screen is a greater challenge due to copious use of glue. Your best defense is to keep the device tethered to a power source which *may* slow internal decay and eventual total shutdown due to high internal resistance. Good luck.
Phone is a ANS UL40 running 7.1.1
Battery will randomly go from partial charge to 0%.
This just started happening after having the phone about 6 months.
If I leave the phone unplugged overnight, it will be dead by morning (this is a new thing, it holds a charge pretty well). Doesn't have to be overnight either, could be just a half hour or something. The battery just dies randomly.
Even if I do have the phone plugged in and have the screen on (watching a youtube stream) it will randomly go to 0% and self shutdown.
Stock battery which seems to be stuck inside the phone. It doesn't seem to come out, I don't know if it's glued in or what.
ANS branded 3.8v 1700mAh 6.46Wh part # UL40BATT limited charge voltage: 4.35v
Printed: "Warning: This battery is built-in and is not removable"
boogersugar said:
Phone is a ANS UL40 running 7.1.1
Battery will randomly go from partial charge to 0%.
This just started happening after having the phone about 6 months.
If I leave the phone unplugged overnight, it will be dead by morning (this is a new thing, it holds a charge pretty well). Doesn't have to be overnight either, could be just a half hour or something. The battery just dies randomly.
Even if I do have the phone plugged in and have the screen on (watching a youtube stream) it will randomly go to 0% and self shutdown.
Stock battery which seems to be stuck inside the phone. It doesn't seem to come out, I don't know if it's glued in or what.
ANS branded 3.8v 1700mAh 6.46Wh part # UL40BATT limited charge voltage: 4.35v
Printed: "Warning: This battery is built-in and is not removable"
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Click to collapse
Its actually removable -
I have the same issue with mine and I just received it as a replacement phone about 3 months ago. If anyone has a clue as to what to do please share. Been to all the blog pages and customer pages related to this model and it seems to be a recurring issue and so is overheating and a dozen other things. What the point in having Lifeline when all the phones that they give or sell don't work.
And I thought it was just me. Needing a lifeline phone seems to mean we get the worst of the worst devices. I had to pay extra for the UL40 because the "free" phone was useless. The UL40 is near useless, and this battery issue makes it unreliable.
i have the UL40 and requested a replacement phone (because of unsustainable malware issues that survived a factory reset) and the L50 they sent me had this issue. i couldn't find a solution and had to request another replacement.
oddly, i occasionally experienced an apparent battery discharge (phone powers off, needs to be connected to power to boot up again) but when it powered back on the battery was at ~65%, clearly plenty of power.
my completely uneducated guess is that the battery terminals in some of these phones are loose, either causing the battery to discharge completely or simply disconnect momentarily, resulting in the phone losing power.