Full Drain the Battery? - AT&T Samsung Galaxy S II SGH-I777

There seems to be a debate on this topic as to whether you should do a FULL drain on your battery and I wanted to know what people's thoughts were on this in this forum.
I've used my phone twice now to the point where it has auto powered down on it's own. I will then hit the 'Power' button to ensure that battery is truly at 0% (the capacitative buttons blink for a second to confirm that I've hit the power button but there is no more juice left to turn the phone on).
I will plug into the wall charger and allow it to charge for 4 hours (usually around 4 hours, I'll check back to see and hit the power button and the onscreen battery display will show 100% charged).
I will unplug my phone, power on and keep using until the phone fully drains and powers off on it's own again before repeating this cycle.
However, others have stated that this is NOT necessary for Lithium Ion battery and can actually damage the circuitry of the battery? I've always been under the impression that you need to do a complete & full battery drain for lithium ion batteries at least 3 -5 full cycles/times before the battery has been conditioned/optimized for capacity.
Maybe I'm wrong...after all I'm coming from a G1 and this practice helped my atrocious battery life on that dinosaur!
If this is wrong, when should I be plugging my phone back in to charge? When it gives me the first warning to charge in (battery level turns orange - I assume this about 20% battery left) or on the "critical" battery warning when the battery icon in the notification panel turns red (assuming this is about 10% battery left)?

from what I've read in the past, letting your phone drain completely down until it shuts itself off is not good for the battery. I could be wrong but thats what I've read

nyydynasty said:
from what I've read in the past, letting your phone drain completely down until it shuts itself off is not good for the battery. I could be wrong but thats what I've read
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Yeah, I've heard both sides and I've conditioned my battery for the G1 because it seemed to drain faster if I plugged it into charge when there was 30% or so still left.
Well, I've done two complete cycles so I guess I'll just try recharging when it hits the red mark next time.
When you plug in to charge? Orange, red or whenever to top off?

i plug my phone in when i go to bed. I dont care what the battery is at. I also charge it while i'm at work so when I leave, its around 90-100%. My battery rarely reaches red.

nyydynasty said:
i plug my phone in when i go to bed. I dont care what the battery is at. I also charge it while i'm at work so when I leave, its around 90-100%. My battery rarely reaches red.
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LOL - that would prematurely killed my battery capacity on the G1! I went thru two batteries before I started draining all the way down. Made a difference between 4-6 hours and 6-10 hours.
Seems like this phone doesn't need to do that tho.
But what're you getting on average for battery life and display on time then?

nyydynasty said:
i plug my phone in when i go to bed. I dont care what the battery is at. I also charge it while i'm at work so when I leave, its around 90-100%. My battery rarely reaches red.
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I do the exact same thing. First with my Captivate and now with the SGS2 and the battery life on my captivate held pretty much exactly the same charge for the entire 15 months I used it. The battery on this SGS2 seems to last about 150-175% of the Captivate battery under the same conditions. I just came back from a week on the road where I spent 9-12 hours a day away from a charger and was using my phone constantly all day long and would get back to the hotel room with 30-40% battery left. Considering I was listening to music, playing plants vs zombies and sending and reading push email constantly throughout the day I am very satisfied with the battery life on this phone. I've never done any kind of conditioning or special battery maintenance.

DefTaker said:
LOL - that would prematurely killed my battery capacity on the G1! I went thru two batteries before I started draining all the way down. Made a difference between 4-6 hours and 6-10 hours.
Seems like this phone doesn't need to do that tho.
But what're you getting on average for battery life and display on time then?
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i stopped looking at my battery stats a long time ago. I'll peak in there once in a while but I dont really care what the stats show because I'm always around a charger. As long as I get through 12 hours or so without charging, i'm happy.

Some devices need a full drain cycle to properly calibrate the fuel gauge - ours does NOT.
Lithium ion batteries don't like deep discharging - in fact discharging them too much will permanently damage them (fortunately, all batteries sold to end users have built-in protection chips to prevent overdischarge - but do you REALLY want to rely on that chip?)
Similarly, they don't like charge being forced into them - so don't "bump charge". (Bump charging is removing and immediately reinserting the charger when the phone says charging is complete.)
For long-term storage, store them at around 50% capacity if not being used. LiIons that are stored at 100% charge lose capacity MUCH faster than ones stored at 50%.
A Li-Ion that has been sitting for a long time (months...) will develop a passivation layer that can be detrimental to performance - a few charge/discharge cycles will fix this. You don't need to do a full discharge/recharge - probably even from 90 to 70 and back up a few times should be fine.

Entropy512 said:
Some devices need a full drain cycle to properly calibrate the fuel gauge - ours does NOT.
Lithium ion batteries don't like deep discharging - in fact discharging them too much will permanently damage them (fortunately, all batteries sold to end users have built-in protection chips to prevent overdischarge - but do you REALLY want to rely on that chip?)
Similarly, they don't like charge being forced into them - so don't "bump charge". (Bump charging is removing and immediately reinserting the charger when the phone says charging is complete.)
For long-term storage, store them at around 50% capacity if not being used. LiIons that are stored at 100% charge lose capacity MUCH faster than ones stored at 50%.
A Li-Ion that has been sitting for a long time (months...) will develop a passivation layer that can be detrimental to performance - a few charge/discharge cycles will fix this. You don't need to do a full discharge/recharge - probably even from 90 to 70 and back up a few times should be fine.
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what about short charging during the course of the day? For instance, while I'm at work, I like to plug it in for a bit and then use it off the charger. Then before I leave, I charge it again for a bit. Do you think thats okay to charge the phone for short ~1 hour bursts?

No, the battery itself doesn't do well with deep discharges, but every device with one has circuitry to manage this and keep it from happening. The phone will shut off before the battery reaches a critically low discharge state. Just as it will cease charging before it blows up. Just because the phone shuts off does not mean that the battery is too low.
Assuming the phone has the proper cutoffs, it's not really any different to do two discharges to 50% or one to 100%. There have been studies that say leaving it on a charger is bad, doing two 50% cycles is worse than one 100%, etc. I've always just trusted that the phone manufacturers design the battery monitor and control circuits correctly and not worry much about it. And I've never had to replace a battery yet and always get acceptable life.

It's lithium ion, not nickel cadmium.
Full drains are bad for lithium ion.
Sent from my SGS II

nyydynasty said:
what about short charging during the course of the day? For instance, while I'm at work, I like to plug it in for a bit and then use it off the charger. Then before I leave, I charge it again for a bit. Do you think thats okay to charge the phone for short ~1 hour bursts?
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That's the best way to charge it.
Sent from my SGS II

MikeyMike01 said:
That's the best way to charge it.
Sent from my SGS II
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that makes me even more glad that its what I've been doing forever - lol
thanks

lithium ion batteries dont like being under 30%. and they also dont do well if they are kept at 80 percent or above all the time. for longest battery life don't just let it sit on the charger all day after it fully charges.

I agree with Mikey here.
Also, batteries take charging current better (less wear) at lower states of charge. That's why I put a variable-current charging algorithm into my Infuse kernels (charginghacks branch on github)
800 mA at low voltages (200 above stock), dropping to 550 near the end (50 below stock).
Unfortunately, charginghacks is likely not going to be possible with our hardware. One of the differences between the I9100 and I777 is a different battery charger circuit - ours is far less flexible.

Entropy512 said:
I agree with Mikey here.
Also, batteries take charging current better (less wear) at lower states of charge. That's why I put a variable-current charging algorithm into my Infuse kernels (charginghacks branch on github)
800 mA at low voltages (200 above stock), dropping to 550 near the end (50 below stock).
Unfortunately, charginghacks is likely not going to be possible with our hardware. One of the differences between the I9100 and I777 is a different battery charger circuit - ours is far less flexible.
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This phone actually charges with the screen on though, so it's not like the Infuse where the battery would drain with the screen on and the phone charging.

MikeyMike01 said:
This phone actually charges with the screen on though, so it's not like the Infuse where the battery would drain with the screen on and the phone charging.
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Infuse would charge with the screen on - but not if the screen was on AND the CPU was cranking.
(worst-case was navigation at full brightness - and I've seen reports that the I9100 also has the same problem.)

Entropy512 said:
Infuse would charge with the screen on - but not if the screen was on AND the CPU was cranking.
(worst-case was navigation at full brightness - and I've seen reports that the I9100 also has the same problem.)
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When web browsing, playing a game, or other general use late at night I'd plug the Infuse into the charger. It would still drain. Doing the same on the SGS II and it at the very least maintains it's battery level, so it's a drastic improvement over the Infuse.

Related

[SOLVED] + [BRAINSTORM] Battery Calibration

Just wanted to open up a thread here to see what we can do about battery calibration issues.
Not sure, but I read around that people are getting phone shut downs at the 10%-15% ranges.
When in actual fact it should be somewhere around the 1%-5% range?
Was wondering if there is some possibility in coding the phone to read the battery state better? Thus, eliminating the need for calibrating the battery through tradition means (ie: wiping, charging, etc)
Thoughts?
EDITS:
We've managed to figure out huge boundaries for the battery.
There are currently two ways to get your battery into "learn mode" - which will adjust the values of your battery to accurately reflect it's "age" and mAh tracking. This will lead to a fix for those of you who are currently facing issues with the battery shutting down anytime before the 1% mark.
1st fix:
1) Drain battery
2) Just as the battery hits "Shutting Down", plug in your charger
3) Let the phone power down
4) DO NOT TURN ON THE PHONE
5) Let it charge up overnight or something along the lines of 4-6 hours, which should ensure it will be fully charged
6) Power up, your phone should be calibrated and will now shut off at 1%
2nd fix:
Head over to the Battery Calibration Tool Thread which spawned off from the discussions here!
>> http://forum.xda-developers.com/showthread.php?t=765609
For those who have been following the thread and wonder what your status_reg value mean theloginwithnoname has kindly provided us with some datasheets and translations, which you can get with the following links:
Binary Conversion: http://forum.xda-developers.com/showpost.php?p=8013370&postcount=548
Then refer to Page 25 of the following datasheet: http://datasheets.maxim-ic.com/en/ds/DS2784.pdf
OR you can try out mtw4991's method to get learn mode done with the battery app that's been created out of this brainstorm thread.
The link to his method is > http://forum.xda-developers.com/showpost.php?p=9583271&postcount=340
I began this thread in other to simply find a fix for our current battery % meter. Basically, users (myself included) were having a problem with inaccurate battery % readings. Some N1's would shut down above 1% and this would leave many guessing when the battery would give out.
Needless to say, here at XDA - we managed to find the fixes. ;-)
And of course, we decided to take it to the next level.
How can we now push more out of our batteries?
RogerPodacter and theloginwithnoname have been working endlessly learning and understanding the how the battery registry works and together with dvgrhl they're finalizing a battery mod app which will help the N1 cope with the "learn mode" and changes. So do thank them for the great work they've been pushing out with! =)
They've helped us hammer out all the core details concerning the battery understanding, values, binaries, and we're wading through the mess to push the limits on the batteries (short of blowing them up as usual of course).
Be patient if the app isn't ready yet. And if you're a n00b, please don't mess around with the registry values and such if you have absolutely no idea what you're doing.
No one is gonna give a rat's poopoo if you blow up your phone and set your house on fire and gremlins kidnap your toes.
Peace out.
This thread is and methodology has served its purpose and many of us from this thread have moved on over to the Battery Calibration TOOL thread. The methods still work, but so do the newer methods at the tool thread, which I personally find is much easier and better.
If you'd like to use the manual method, it'll still work.
For those more interested in the newer method and I encourage you to do so - head on over through this link > http://forum.xda-developers.com/showthread.php?t=765609
+1
It happened to me yesterday. I am playing with my phone and I needed to check an important address on Google Maps, so I was thinking "Oh great I still have 9% battery" and then all of a sudden BOOM. It powered off. I mean seriously WHY have those extra 9% if I am never going to use them. So In reality my phone battery is like 80%
100%-(first 10% which drain in like 5-6minutes) - 10% that I never use cause the phone shuts off = 80% BOOOOOOOOOOOOOOOOOO NOT COOL
happened to me on cm 5.0.7.1 about 7% battery
I guess this would be an appropriate time/place to ask this question. I had someone PM me asking how to calibrate their battery and I didn't know if I provided them with the correct response. What I've always done is let the battery drain ALL the way down until it dies~usually about 1% and then fully charge the phone while it is off. Then, let it die down once again on that charge and repeat the charging while the phone is off. Is that the correct way to calibrate the battery or am I taking unneccesary steps?
THATTON said:
I guess this would be an appropriate time/place to ask this question. I had someone PM me asking how to calibrate their battery and I didn't know if I provided them with the correct response. What I've always done is let the battery drain ALL the way down until it dies~usually about 1% and then fully charge the phone while it is off. Then, let it die down once again on that charge and repeat the charging while the phone is off. Is that the correct way to calibrate the battery or am I taking unneccesary steps?
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No idea as well honestly. I've never charged my phone while it's off... so that might be the issue...
But then again, my phone has often turned off at the 10% mark. So that's why I thought I'd get more input here on how we can actually find a way to calibrate our batteries or something.
i have two oem batteries and a dock..Everyday I completely drain the first and swap it out with a fully charged one off the dock and both batteries perform great and never shut down above 1% every single time. So the batteries are always completely drained and then have a slow no stress recharge, maybe this is why mine go to 1%?
chowlala said:
No idea as well honestly. I've never charged my phone while it's off... so that might be the issue...
But then again, my phone has often turned off at the 10% mark. So that's why I thought I'd get more input here on how we can actually find a way to calibrate our batteries or something.
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I notice that if I charge my phone while it is off and take it off about 20 minutes after the light turns green, the discharge rate is MUCH slower than if I charge it while the phone is on. Or, I will charge it while on, let it get to 100%, turn it off and continue to charge until the light turns green again. Either of those two ways give me the best results for battery life.
Doesn't the Li-on type of battery calibrate itself when charged from 0% (or the specified minimum) to 100%?
THATTON said:
I notice that if I charge my phone while it is off and take it off about 20 minutes after the light turns green, the discharge rate is MUCH slower than if I charge it while the phone is on. Or, I will charge it while on, let it get to 100%, turn it off and continue to charge until the light turns green again. Either of those two ways give me the best results for battery life.
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Hmm. Interesting thought. Guess letting it charge to 100 while its on is one thing, then turn it off so it maxes out before daily use. I'll try that tomorrow morning and see.
Stats have been recalibrated to pershoots kernels already. So tomorrow will be a good testing day.
LiOn batteries should NOT be drained completely. It is bad for them. You should simply charge to 100%, turn the phone off, let it continue to charge (you may be at 100% when in OS but not truly 100% to the battery) and then wipe battery stats.
hah2110 said:
LiOn batteries should NOT be drained completely. It is bad for them. You should simply charge to 100%, turn the phone off, let it continue to charge (you may be at 100% when in OS but not truly 100% to the battery) and then wipe battery stats.
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Yeah, the discharge part is actually true. There's more info here bout the batts, but nothing much bout calibration.
http://forum.xda-developers.com/showthread.php?t=669497
chowlala said:
Hmm. Interesting thought. Guess letting it charge to 100 while its on is one thing, then turn it off so it maxes out before daily use. I'll try that tomorrow morning and see.
Stats have been recalibrated to pershoots kernels already. So tomorrow will be a good testing day.
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Click to collapse
The biggest thing I noticed right off the bat in doing this was that normally my battery drains from 100% to 90% in less than 30 minutes. After doing what I suggested, I see that my battery discharges much slower from 100% to 90%! Hope it works for you.
My phone was doing that ALL the time. Here's what i did that fixed the issue for me.
1.) Let my phone die as usual.
2.) KEPT IT DEAD... for 1 day
3.) Charged with the phone OFF for 1 day.
4.) Went to RA's recovery as soon as i turned the phone on and reset Battery Settings.
5.) Rebooted and all is well.
I hope this helps someone else.
(My phone would die at 13% EVERY time. It got really annoying when trying to Navigate when i forgot my USB cord for my PowerCup. :< )
And yes i know about the whole not letting Lion Batteries die. When i worked for T-Mobile and the customers would bring in their N1's doing this, every call to HTC this is what they told me to do. (Minus the whole awesome recovery and such). They said letting the battery drain will not hurt the phone as long as it regains 100% charge after the initial drain.
AGAIN. This worked for Me. So im not promising you anything. Plus the batteries are only 25 bucks from Google. And i have 4 extras... Just in case. I would invest in some if i were you. Cause lord knows, were going to do some SERIOUS stuff to our phones. Extra Batts dont hurt.
Lithium batteries don't have memories, that's a leftover idea from the old Nickel Cadmium (NiCad) and NiMh (Nickel Metal-Hydride) days. The idea with Lithium (Ion & Polymer) should pretty much just be charged up whenever. Letting them be drained completely isn't good for them and will reduce their lifespan (reduced mAh) although it won't almost immediately kill them ala lead-acids. Overcharging them via a circuit with a poor cutoff also isn't good for them as they'll heat up, phones or any decent AC charger should stop charging when they hit 100% though.
Probably about the best you can do is charge it to 100%, pull the battery and reboot the phone and then reboot it again. The charge calculation will be based on the rated mAh of the battery which depending on the quality of the battery and the charging system of the device could end up giving you some funny figures. Not much you can do about it though.
I just wanted to say that this link does mention a proper calibration charge, it just does not go into detail.
Item 3 of "General Lithium-Ion Battery (LIBs)Usage":
• Although it is said that LIBs do not have memory, it's not entirely true. LIBs have gauges that monitor performance of cells, and if you do a lot of small charges, it won't let those gauges to monitor a full battery potential, causing an invalid indication of charge level. A complete charge/discharge should be made when battery capacity seems reduced, that will calibrate gauges and they will provide your phone with correct charge level status. A full charge/discharge cycle should be done every 30 (or so) partial charges.
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My assumption of a complete charge/discharge cycle would be:
1. drain battery until the device dies
2. charge the battery to 100%
3. power device on
4. drain battery fully until device dies (no small charges!)
5. charge battery to 100%
This should allow the battery gauges to recalibrate and improve battery capacity.
People seem to be in the dark about lithium ion batteries, how they are charged, and how the device estimates battery charge remaining.
Lithium batteries do not have memory effects, but the phone does keep a file with charge info about the battery; it uses this to estimate charge left and how to charge safely when the device is powered on.
When properly charging a Li-ion battery, the last 10% of the charge should take almost as long as the time it takes to charge from 0 to 90% (well about half as long meaning a full third of the charging time should be going into the last 10% of the charge) Charging with the device off, charges the battery more completely and consistently.
Li-ion battery chargers use a type of charge cycle called constant amp/constant voltage. The battery will be force fed amps until the battery's voltage peaks and it will then be fed a constant voltage. (around the 90% charge mark) During the constant voltage phase, the amps that the battery is taking in will be monitored; as the battery gets closer to full charge the amperage will drop more and more, until it is just a tiny trickle. When it gets to that point, the battery is fully charged. Obviously charging with the device still powered on creates a problem for that type of charging. So the battery can only be charged to the peak voltage, then the charge cycle must stop; as the last 10-15% of the charge can not be completed safely.
It is always good to let a device run until dead and then charge with the device off a couple times when the device is new, and then charge the device from empty while powered off once every couple months. (do not do it too often, as Li-ion batteries prefer to be between 50-80% charge for longer service life) This allows the device to maintain a proper reference data file on the battery and its charge state. this data file is what Android uses to estimate the charge in the battery, if the file is not accurate, the device may power down sooner than it should, or not charge fully to a true 100% state. (peak voltage state when powered on that is)
Also, Li-ion batteries are rated for capacity from a discharged voltage of 3v. So a 1500Mah battery is rated to provide 1500mah of power from fully charged to a final discharged voltage of 3v.
I do not know what the minimum operating voltage of various devices is, but if it is higher than 3v; then the phone must shut down at its min operating voltage and not the 3v needed to get full capacity. My Nexus one shuts off around 3.5v so there is around 25% of the actual rated battery capacity left. (remember what I said about Li-ion batteries liking to be between 50-80%, this left over capacity means that running the battery dead repeatedly is less harmful than if you drained the battery to a true 0% state)
There is also a voltage drop on a battery when under load. So if you are putting a heavy load on the device (like a 3D rendered game heavy gps use) then the battery voltage may drop to below the device’s min voltage. This means that if the phone shuts down during this time, you could probably turn it back on and get a few hours of standby or a few more minutes of light use. This could be another cause for people seeing shut downs when the battery gets around 10%.
The amount of power in a battery is high, especially in Li-ion batteries with their high energy densities. Over charging a Li-ion battery can cause an explosion, literally, that little battery in your phone could remove some fingers. Over discharging is bad as well, as it can start a fire; though like I mentioned above, the cut off voltage is above the 0% state, so that is unlikely here.
Ive proposed this before and got a bit shouted down, but thumbs up if anyone comes up with anything
As i see it, its not a problem with the battery. Its a problem with the battery meter. Since following a regime of deleting my batterystats.bin file, i dont see that issue. Its the same on my g1 as it is on my n1.
This is what i do... when i charge my phone, i charge it until 100%. When it reaches that 100%, i use either use the terminal or root explorer to delete the batterystats.bin file. After which i immediately power off the phone. Now, when its powered off(and still attached to the usb charger) the light should be green. But usually its not! Sometimes it charges up to a full hour longer before it turns green! When it turns green, power the phone back up and enjoy tue extra kick of battery life. Its not actually gaining battery life, its just resetting tue battery meter in the phone. This could only be done with a rooted phone. Oh, i think that this whole innaccurate battery meter thing is a problem with android in general. The meter becomes innaccurate with time. Sometimes extremely innaccurate.
Using the terminal...
su(press enter)
rm /data/system/batterystats.bin(press enter)
Then power off
Wow. Lotsa pewpewz here. Haha.
Again, after all the discussions, seeing that most of us agree the N1 keeps "stock" of how the battery chargers, is there a way for us to check or see how the battery is being calibrated, etc?
Not so much an app to modify the calibration, cuz that'll just be too dangerous, but something more like a tool to monitor it, so we know if it's calibrated right or wrong.
Deleting the batterystats.bin file isnt an app. Its either a script you run to delete it or physically deleting it. And its not dangerous. Ive done it well over a thousand times with my g1 and n1 combined. If you wanted to find out how the calibration work, i guess you could make a copy of your batterstats.bin and read it

Does overnight charging damage battery?

I notice that there's a warning message when the phone is fully charged, advising you to disconnect the charger. I usually leave my phone charging every night, meaning that it's still connected to the charger for hours after it's fully charged. I'm pretty sure that the S2 has "smart" charging, but would the overnight charging damage the battery by exposing it to unnecessary heat for this extended period?
No it shouldn't. Like you said the phone has the ability to shut off the charge when the battery reaches 100%.
I've been charging mine all night for most nights out of the past 3-4 months and it's fine.
That warning is essentially Samsung's attempt to give you a green consciousness, since leaving the charger connected to the wall draws a trickle of current. Sammy figures that millions of people following those instructions to the letter will help save the planet.
It will reduce your batteries life, leaving it on the charger. Will it does stop charging it then drains to 99% then tops it up, which over time uses up the recharge cycles and will reduce the time until it can't hold a charge.
Lithium ion battery doesn't have recharge cycle.
jzmtl said:
Lithium ion battery doesn't have recharge cycle.
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Exactly. This was true until Litium Ion batteries came the norm in handsets.
Nowadays its just to be seen as being 'green'
That is strange since this site devoted to teaching about batteries makes it seem like they do. But also reading it says that being at a constant full charge is more damaging then cycling the battery.
That is in the second paragraph under the "Depth of discharge" chart on this site
http://batteryuniversity.com/learn/article/how_to_prolong_lithium_based_batteries
With the frequency cellphone batteries are charge/discharged, they crap out after two years anyway, and unlike some other fruity product it takes us 10 seconds to plop in a new one, so don't worry about it.
Even if it damaged your battery the effect wouldn't come noticeable before a long time I think. And in case the battery does get damaged, you can always replace it, that's one of the nice things about this phone, if you compare it for example to an iphone.
tomascunill said:
...And in case the battery does get damaged, you can always replace it, that's one of the nice things about this phone, if you compare it for example to an iphone.
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Click to collapse
exactly why i didn't buy an iphone
The only things really damaging your battery are:
- excessive heat
- heavy use while charging
- turning on the phone over and over after it turned itself off on it's own due to low battery
there are more, for sure, but just to name a few.
I always charge my phones over night and my HD2's battery is as good as ever after 2 years. My SGS2's battery is still the same, and I still thing that when the battery is full there are no discharge/recharge cycles but something like a suspend mode in the charger.

Battery drops 30% on phone reboot

I'm having this problem with my i777.
Sometimes when I reboot the phone the battery charge drops enormously, like 30% or so. For example, I will be doing things with the phone, the charge will be at something like 60% then reboot and right after reboot it says charge is 30% which doesn't make much sense.
this happens with the stock battery but the effects seems to be more pronouced with some batteries I bought on ebay.
Anyone has any idea what's going on?
what rom are you running on?
bartolo5 said:
I'm having this problem with my i777.
Sometimes when I reboot the phone the battery charge drops enormously, like 30% or so. For example, I will be doing things with the phone, the charge will be at something like 60% then reboot and right after reboot it says charge is 30% which doesn't make much sense.
this happens with the stock battery but the effects seems to be more pronouced with some batteries I bought on ebay.
Anyone has any idea what's going on?
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Normal behavior of our fuel gauge hardware - high load (boot process) immediately after a reset confuses it and makes it report low. Effect is much more pronounced at lower states of charge.
pham818 said:
what rom are you running on?
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Rooted stock 2.3.4
build number: GINGERBREAD.UCKH7
Entropy512 said:
Normal behavior of our fuel gauge hardware - high load (boot process) immediately after a reset confuses it and makes it report low. Effect is much more pronounced at lower states of charge.
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Click to collapse
That's exactly right. Tends to happen more on lower states of charge.
Does this mean that the charge indicator will go up after the reboot? Or maybe it will take longer to drop and the effective battery life will be the same.
Yes when this happens to me my bettery either dies extremely slow or my percent just goes up..
Sent from my SAMSUNG-SGH-I777 using XDA App
Smacdallas said:
Yes when this happens to me my bettery either dies extremely slow or my percent just goes up..
Sent from my SAMSUNG-SGH-I777 using XDA App
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Click to collapse
I see this too. I will be at ~40%, reboot and see 10%. Come back after a while to 12%, and it stays on 12% with like an hours worth of heavy use before going lower. If I look at the battery usage, it trends down, then drops, but stays level, then about when the trend would have been it starts dropping again.
I thought I just needed to calibrate the battery, as I just flashed a new ROM. But, it keeps doing this after a week, and several charge cycles.
Guess I'm relieved to see this weird behavior is not indicative of a problem.
Sent from my Galaxy S II (i777)
bartolo5 said:
That's exactly right. Tends to happen more on lower states of charge.
Does this mean that the charge indicator will go up after the reboot? Or maybe it will take longer to drop and the effective battery life will be the same.
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Correct - because the gauge thinks the battery is lower than it actually is when this happens.
Attached a screenshot of the battery use with the big drop in effect.
I particularly think this is a bug and Samsung should fix this behavior.
It can't be changed without hardware alterations.
As with anything in engineering, there are tradeoffs. The positive aspect of this fuel gauge design is that it does not require ANY calibration. No wiping battery stats, no "always flash firmware at 100%" - none of that.
The negative is that in a few corner cases, it gets thrown off temporarily. This is basically the only known one.
Ive noticed this as well with both Stock and ICScreweD. I just try to reboot as least as possible.
greystealth said:
Ive noticed this as well with both Stock and ICScreweD. I just try to reboot as least as possible.
Click to expand...
Click to collapse
If you reboot at higher states of charge, OR reboot when on external power, you should not see this issue.
I just had this same problem lol. I was at 42% and when I rebooted my phone it dropped to 23%....This was a few hours after the OTA update to 2.3.6.
I had the same problem also.
-Battery would not charge to 100% ( it would charge between 97% -98%)
-Battery would drop 20% or 30% percent (when reboot).
I tried to recharge many times and cycles the battey but nothing would work.
I tried changing kernal, modem and roms . Nothing would work.
I actually thought i messed my phone up.
So i tried something that work for me.
1) i would let the battery drain till it was completely dead!
2) I would take battery out for 5 minutes.
3) put battery in and charge with phone OFF till it reaches 100%.
4) unplug charger from phone and take battery out and wait 5 minutes.
5) put battery back in and plug charger up and wait till phone marks 100% again ( This time the wait was longer to get to 100%).
6) i repeated step 5 untill finally the phone would mark 100% faster
7) unplug phone and then wait to see the battery status ( if your phone mark 99%) plug charger to phone and let it charge till it reaches 100% again. once it reach 100% reboot and repeat step 7 untill you reboot and it would show 100%.
not sure if this might work for anyone else but it did work for me. battery would charge to 100% and i don't have my phone drop 20-30 percent after reboot.
If it drops 20-30% on a reboot when the battery is near full, you may have a defective battery.
I've only seen major drops on reboot when the battery is low to begin with, never when at higher states of charge.
Doing a full discharge on Li-ion batteries puts a huge stress on it and greatly decreases the life of the battery. To get the longest life out of a battery, you want to generally stay in the medium range of charge (Don't over charge it, and don't discharge it too much). Cars like the Chevy Volt employ these techniques to encourage a longer battery life, however with phones, you get users that think discharging the battery all the way solves problems. If you want to see the true battery life that the fuel gauge averages from, press *#0228# in your dialer and check the battery voltage. Full is around 4.1v and discharged I believe is around 3.5v or so. (maybe 3.3? not sure)
3) put battery in and charge with phone OFF till it reaches 100%. <-- is probably what fixed it, and why I switch batteries instead of charging on my phone because the charger is able to control the current and voltage better than with a slight load on it (with phone on)
I'm sure that that user cut off at least 5% of his overall battery life with overcharging it like that though...
Same issues here pending the ROM I'm using.
4.2 volts is the upper limit for li-ion - and actually, it hits that at around 95% charge.
The method for charging Li-Ion:
Charge with a current limit initially - on our devices this is 650 mA.
Once you hit 4.2 volts, do NOT go above this - maintain voltage at 4.2 volts or lower regardless of current
Once current drops to around C/10 (on our devices, this is about 160 mA), shut off charging completely.
The phone's charge controller does this all automatically for you.
There's usually a timer/averaging filters in the final stages of charge termination - which is why "bump charging" can push a little extra into the battery - but this will lead to degradation in battery total capacity.
As somewhat of an extra trivia on Li-ion batteries, Motorola has apparently managed to get batteries that have nominal voltage at 3.8v and max charged voltage is around 4.3v as opposed to 4.2v.
Hunt3r.j2 said:
As somewhat of an extra trivia on Li-ion batteries, Motorola has apparently managed to get batteries that have nominal voltage at 3.8v and max charged voltage is around 4.3v as opposed to 4.2v.
Click to expand...
Click to collapse
is it Li-ion tech though?
Sent from my SGH-I777 using Tapatalk

is it better to charge the Tablet and Keyboard Dock separately?

Is it better to charge them separately?
From what I heard, the dock charges the Tablet. So if I charged with the two connected, the dock would charge, and it would in turn charge the Tablet...sounds kind of inefficient to me, and maybe even bad?
I usually charge my TF101 tablet from it's dock and have done so since September, perfectly fine and no negative impact on the battery. Just don't make a habbit of burning the batteries too low, like 1% before you charge.
My dock does drain a little faster after having gone through a bunch of heavy discharges but that's why I usually charge before I get to like 3% .
Spidey01 said:
I usually charge my TF101 tablet from it's dock and have done so since September, perfectly fine and no negative impact on the battery. Just don't make a habbit of burning the batteries too low, like 1% before you charge.
My dock does drain a little faster after having gone through a bunch of heavy discharges but that's why I usually charge before I get to like 3% .
Click to expand...
Click to collapse
That's odd since it is recommended that you run the batteries down before charging them instead of putting it on the charger before it gets below 10%. Charging them without running the power down has a negative effect on the amount of charge it can hold.
That is not required anymore.The ideal charge level for these batteries is about 40%.
Charge cycles aren't a problem either so discharge is required once a month or even more.
These devices use LiPo and Co batteries.
For these, it is recommended NOT to fully let the battery discharge (unlike older batteries with memory effect).
It is however recommended to fully charge then fully discharge your battery ONCE when you first use it on order to calibrate the battery (ie: let the software learn what level means full and what level means empty)
Sent from my GT-I9100 using XDA App
eraursls1984 said:
That's odd since it is recommended that you run the batteries down before charging them instead of putting it on the charger before it gets below 10%. Charging them without running the power down has a negative effect on the amount of charge it can hold.
Click to expand...
Click to collapse
You can check the link in my Sig. there is some info on recent batteries and calibration.
Yup, running it till it shuts off is mainly to calibrate the battery gauge. Most Lion batteries have auto shutoffs built into them to prevent discharging past the point of no return (which is why ebay batteries are so cheap, usually they lack this and other features, like temp sensors to kill the device before it melts)
As to charging both devices, i dont see how charging each together would harm anything aside from running more power through the dock might eventually wear it out? Honestly i dont think you have anything to worry about XD
But I can see the dock being discharged to zero so often. So far it has happened 4 times without me even knowing it since its often connected to the tablet. I wish there was a way to use the dock and disable the charging to the tablet.
Its better to have a few full discharge n full charge cycle for any new battery operated product to maximize the new battery capacity after a few cycles it will reach its peak capacity.
iceman127 said:
Its better to have a few full discharge n full charge cycle for any new battery operated product to maximize the new battery capacity after a few cycles it will reach its peak capacity.
Click to expand...
Click to collapse
But I'm sure on many occasions just by the usage and nature of the dock that it will end up being drained to 0% quite often. I don't think my dock battery will survive too long -.-

Question How critical is it to just charge to 80%

I keep reading that you should try and just charge your phone to 80% to help keep the battery healthy, as going to 100% can shotren the life span of the battery.
How ciritcal is this?
I know letting your phone run down to 0% is bad as it takes a fully clylce then to get back too 100% and this is not good for the battery long ter, but i must confess i usually let my battery get to around 50/60% ish then charge back up to 100%
I've always charged my phones fully and never noticed any issues. Maybe if you plan on keeping a device for 10 years, but for the usual lifetime of a phone it's just fine. My OP7 is 2 and a half years old now and still has 86% battery health. I've seen others in Telegram groups say that they never charge to 100% and when they post their battery health it's not much different from mine, sometimes even less.
I think modern batteries are fine being fully charged ... otherwise the OEMs or battery manufacturers would limit them to 80 or 90% by default.
Nimueh said:
I've always charged my phones fully and never noticed any issues. Maybe if you plan on keeping a device for 10 years, but for the usual lifetime of a phone it's just fine. My OP7 is 2 and a half years old now and still has 86% battery health. I've seen others in Telegram groups say that they never charge to 100% and when they post their battery health it's not much different from mine, sometimes even less.
I think modern batteries are fine being fully charged ... otherwise the OEMs or battery manufacturers would limit them to 80 or 90% by default.
Click to expand...
Click to collapse
I guess I have some buffer
mosio said:
I guess I have some buffer
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Click to collapse
Hehe yea, I guess they all show 102% then because I have that as well
I like the adaptive charging, set up your bedtime and alarm for getting up (or turning over) After bedtime, phone gets trickle charged to achieve 100% at morning alarm. No excess heat etc. Phone then lasts me all day till bedtime when put on airplane mode, switch off Wi-Fi, & sleep. Works for me.
I'm showing 106%
I always charge to full, using adapting charging over night. Charging slowly and keeping temperature down is more important than keeping it to 80% from my understanding.
I just lay my phone on a slow charge Qi pad every night and when I get up it is at 100%. Nexus 6, Pixel 3, now Pixel 6. Perhaps my battery life went down a bit on my Pixel 3 after 3 years, but not enough to notice. I think 100% charge (at least slow charging) is safe for 3 to 5 years of battery life.
Li's like frequent midrange power cycling; it can extend the lifespan hundreds even thousands more full charge cycles.
Voltage and temperature are the Li's biggest stress factors. Low or high temperature charging can cause Li plating.
The higher the cell voltage, the faster it degrades.
The same is true with temperature.
Personally I just replace them every year or so as a failed Li can severely damage a phone. They tend to swell during a failure which can easily damage the display.
My Samsung S10+ is 27 months old now. I'm charging it to 80% mainly daily. Had maybe max 20 full charges and only once or twice to zero. I'm at 86% battery health (according to 146 sessions). Was 92% six months after buying brand new.
I think it helps. Also since the battery is OK (4100mah), dont need that extra 20%.
EDIT: 15W Samsung "fast" charging. As fast as that is ...
Zakelinho said:
My Samsung S10+ is 27 months old now. I'm charging it to 80% mainly daily. Had maybe max 20 full charges and only once or twice to zero. I'm at 86% battery health (according to 146 sessions). Was 92% six months after buying brand new.
I think it helps. Also since the battery is OK (4100mah), dont need that extra 20%.
EDIT: 15W Samsung "fast" charging. As fast as that is ...
Click to expand...
Click to collapse
A Li is considered degraded when it reaches 80% of it's initial capacity. This signals the end of its useful service life.
Degraded Li's are more likely to fail.
Trust me it's better to replace it before it fails...
I think Better Battery Stats made that reco back in the day.
Charge to 80% and plug in at 10%.
Not so sure that really matters anymore though.
Both my 2 XL and Pixel 5 were plugged in before bed, unplugged when I got up, plugged back in when I hit 10-15% or when I went to bed.
If you plan on keeping your device for a long time (like 3-4 years) doing the unplug at 80% and plug in at 10% might make a diff.
Az Biker said:
I think Better Battery Stats made that reco back in the day.
Charge to 80% and plug in at 10%.
Not so sure that really matters anymore though.
Both my 2 XL and Pixel 5 were plugged in before bed, unplugged when I got up, plugged back in when I hit 10-15% or when I went to bed.
If you plan on keeping your device for a long time (like 3-4 years) doing the unplug at 80% and plug in at 10% might make a diff.
Click to expand...
Click to collapse
10% is too low. It causes a lot of stress on the battery as it drops below 20% to charge from that starting point or lower.
Worse there's little usable energy after 20% because of the lower voltage. The phone uses the same wattage which is determined by V×A=W, so as the voltage drops it needs more milliamperes to make the same wattage. The discharge rate increases as the cell voltage drops.
A better low cut off is 30-40% or even higher and a high cutoff of 80% although 62% is optimum.
The Li likes frequent midrange power cycling. Charging beyond those parameters is for your convenience at the cost of battery lifespan.
Batteries are cheap and most are easy to replace... so I don't sweat it.
I expect a service life of 1-2 years on a heavily used N10+ battery.
However charging in the 40-72% range yields the most rapid fast charge in the shortest time so it makes sense to use this whenever convenient.
Well, I know things have been updated within Googles code itself.
"Adaptive Charging" / "Adatptive Connectivity" additions.
This was a real big problem for me with my HTC 10, (2016)
Battery degradation threads starting popping up.
I installed Accubattery after 1.5/2 years of owning the device and the battery was degraded to about 77% capacity at that time, IIRC. I was charging to 100% at that time, also.
So, I began charging stricly to 80%.
Compared to my HTC One M8 that to this day still has 90% capacity, and I used that device from the day Verizon released (3/2014) it until the day Verizon released the HTC 10 (5/2016).
I somehow managed to use the HTC 10 up until I bought the Pixel 5 on release day (10/2020).
I was charging the HTC 10 like 3 times a day just get through, and even went back to the HTC One M8 at one point because I had enough, but was waiting for the P5 to drop.
So to answer the question, I do believe it helps.
I do think that Adaptive charging/connectivity help, as well.
I take the view that if I don't need all the capacity on a particular day I charge no higher than 70%, which lands me around 30% end of day. Otherwise I'll guestimate what I need. Off to take some photo's tonight, so will probably charge it to 90% or so.
If you like fiddling around you can use something like Tasker to switch a smart plug that your charger's plugged into on and off at what you consider appropriate battery levels. Makes it all painless once set up. Or you can buy some extra hardware too. I use this in my car to limit the phone's max charge and temperature as, for me, I think most and fastest damage is done in a hot car float charging the phone at 100%.... https://chargie.org/ Not cheap but ok in my mind to hopefully extend the service life of the phone's battery. Less than the cost and hassle of replacing a battery anyway! (I'm not associated with Chargie other than as a customer)
OK, admittedly off-topic, but, this kind of sounds like a variation of the guidance I use for charging my electric car. Don't charge it unless it drops below 80% (so don't keep topping it up), but don't let it go below 20% regularly either. I mostly plug it in at around 60% and let it fully charge. Given the cost of a replacement battery would be more than the total value of the car, I hope this gives me 10 year of life.
Note10.1Dude said:
OK, admittedly off-topic, but, this kind of sounds like a variation of the guidance I use for charging my electric car. Don't charge it unless it drops below 80% (so don't keep topping it up), but don't let it go below 20% regularly either. I mostly plug it in at around 60% and let it fully charge. Given the cost of a replacement battery would be more than the total value of the car, I hope this gives me 10 year of life.
Click to expand...
Click to collapse
EV metering is set up differently. What shows as 100% is likely a conservative 80% charge. Research for that variant.
A 35-40% low cut off is probably better as going lower generates more heat causing needless stress... unless you need that capacity.
Just downloaded the accubattery app and then fully charged but it’s estimating 6,401mah. Must be wrong and needs to calibrate over a few days.
I’ve never had any problems charging to 100% before so I’m not stopping now. I’ll be deleting this app if it keeps warning me like it has done.
Andyzurbs said:
Just downloaded the accubattery app and then fully charged but it’s estimating 6,401mah. Must be wrong and needs to calibrate over a few days.
I’ve never had any problems charging to 100% before so I’m not stopping now. I’ll be deleting this app if it keeps warning me like it has done.
Click to expand...
Click to collapse
Turn it off then.
Andyzurbs said:
Just downloaded the accubattery app and then fully charged but it’s estimating 6,401mah. Must be wrong and needs to calibrate over a few days.
I’ve never had any problems charging to 100% before so I’m not stopping now. I’ll be deleting this app if it keeps warning me like it has done.
Click to expand...
Click to collapse
Accubattery just provides a guide. See here:
battery drain
Hello, I'm using a pixel 6 with two cards sim. When I go to sleep the phone is fully charged and internet/wifi is turned off. When i wake up i have 88% battery (I lose 1,5% per hour). In battery use i see Ims Service. I did a test and in...
forum.xda-developers.com
I used to cycle from full to empty on my Pixel 2 before recharging, at about 3 years the battery couldnt last until lunch anymore. This meant more cycling, and I could fully discharge/recharge it 3 or 4 times a day. Within 6 months the battery only lasted 5 minutes, it was stuffed. Phone always hot and needed to stay on a charger 24/7, would turn off if I opened the camera without usb power connected.
Held out about 6 months on a permanent usb battery bank, was such a slog to wait until the Pixel 6 was released.

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