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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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Click to collapse
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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Click to collapse
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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Click to collapse
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.
Click to expand...
Click to collapse
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?
Click to expand...
Click to collapse
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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Click to collapse
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.
Click to expand...
Click to collapse
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.)
Click to expand...
Click to collapse
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.
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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Click to collapse
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.
Click to expand...
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
Click to expand...
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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Click to collapse
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.
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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
hi all,
anyone knows if there is an app or a way to check what is the voltage being pumped into the s2 during charging?
i am not referring to the voltage measured on the battery as i understand that is the voltage from the battery to the phone
tx
With a supported kernel, CurrentWidget will.
Battery Version 1.0.9
That's the name of an application i am using: it shows many numbers about your battery, and makes estimations about how much time left for it to drain, and how much time is left using a specific activity till it's drained.
The application has a standard battery voltage meter, and it changes if you plug/unplug the charger, so maybe you can calculate the difference? Does it work that way?
hi bro
currentwidget can check the voltage being pumped out from wall charger to the phone?
Hello, I've recenty installed Battery Circle from the F-Droid repos on my SG Wifi 4.2 (UK version).
I don't know how accurate the voltage readings are but I have noticed that when the battery drops to 15% capacity (and you get a warning to plug the charger as soon as possible), the battery is still on 3.55/3.6 Volt, which is way above the safe limit of 3 Volt, as suggested by this article on Battery University:
http://batteryuniversity.com/learn/article/charging_lithium_ion_batteries
Over-discharging Lithium-ion
Li-ion should never be discharged too low, and there are several safeguards to prevent this from happening. The equipment cuts off when the battery discharges to about 3.0V/cell, stopping the current flow.
Click to expand...
Click to collapse
I've let the battery drop down to 3% and it was still above 3.5V.
I always switch off the device when I charge it, it that makes any difference.
Any clues? Thanks
I know it's rude but I need to bump this thread.
By the way I've let the SGP drop down to 2% battery and still showed 3.49V in Battery Circle. I wonder if either the battery percentage or the voltage indicator are reliable.
If you want to know the true voltage state of the battery remove it and check it with a voltmeter.
AEVAREX said:
If you want to know the true voltage state of the battery remove it and check it with a voltmeter.
Click to expand...
Click to collapse
I know this is not the same device but i let my yp-g1 (sgp4.0 for those not familiar with model numbers) drop all the way to 0, something I didnt think was possable. what i did was plugged it in and let it sit for about 10 minutes until it had enough charge to turn on and let it finish charging, good as new. What I learned from this is that the battery will always have some charge, however, it will not necessarily be enough to turn on. also batteries tend to output just a little more than they are speced, for example, if you take a standard brand new AA battery and hook up a multimeter to it, it will read something along the lines of 1.8 volts, this is ok and the battery in thease devices does the same thing. in the end, don't worry about it.
I have developed a kernel patch that allows controlling the charge voltage of the battery. Lowering the charge voltage will typically increase battery cycle life by 2x for 0.1V and potentially much more at high temperatures. The default charge voltage is 4.3V, so with 4.2V you can expect 2x the battery life; with 4.1V 4x the battery life (the battery won't be fully charged).
The patch adds a new sysfs control: '/sys/devices/i2c-0/0-006a/float_voltage'. The setting is in milli-Volt; 3800mV - 4300mV is allowed. The charger supports 20mV increments.
For setting the charge voltage permanently, you can add something like:
echo 4100 > /sys/devices/i2c-0/0-006a/float_voltage
to an init script.
For my N7:
4.0V -> 73% charge
4.1V -> 83% charge
4.2V -> 93% charge
4.3V -> 100% charge
(The patch is against the stock kernel.)
The patch is included in the ElementalX kernel:
http://forum.xda-developers.com/showthread.php?t=2389022
and the Glitch kernel:
http://forum.xda-developers.com/showthread.php?t=2449919
anyone care to try first? is it any different than undervolting with custom kernel?
adichandra said:
anyone care to try first? is it any different than undervolting with custom kernel?
Click to expand...
Click to collapse
This is very different. It isn't supposed to increase battery runtime, it's supposed to decrease it.
It allows allows to not completely charge the battery. In return, the battery won't deteriorate as quickly. Making up numbers here: if the battery would normally survive 300 charge cycles (charged to 4.3V); if you only charge to 4.2V (or about 93% capacity), the battery would last for 600 charge cycles before it's dead.
ah i thought this tweak was about to give double battery life in one single charge. might be usef for others but not me though since i never use a gadget more than 18 months. thanks
adichandra said:
ah i thought this tweak was about to give double battery life in one single charge. might be usef for others but not me though since i never use a gadget more than 18 months. thanks
Click to expand...
Click to collapse
No it extends your battery life as in the longevity. The battery life that we usually think of is how long the battery will last on a charge like you were thinking. That's not what this mod is for. Such a mod that you were hoping for doesn't exist.
tiny4579 said:
No it extends your battery life as in the longevity. The battery life that we usually think of is how long the battery will last on a charge like you were thinking. That's not what this mod is for. Such a mod that you were hoping for doesn't exist.
Click to expand...
Click to collapse
Oh how they can wish though. Though still good work regardless, and very useful.
Anyone know the actual estimate for the amount of charge cycles the battery can handle before giving up the ghost?
I tend to agree with adichandra.. In today's consumer market, most gadjets are usually obsolete after 18 months..
Sent from my Nexus 7 using XDA Premium 4 mobile app
So charge cycles are extended by never allowing the battery to charge to 100%? Sounds similar to a feature on my thinkpad laptop that let's you set the charge and discharge thresholds.
Thank you for posting this!
OJ in Compton said:
So charge cycles are extended by never allowing the battery to charge to 100%? Sounds similar to a feature on my thinkpad laptop that let's you set the charge and discharge thresholds.
Click to expand...
Click to collapse
Yes. Same idea. Some Samsung laptops have this as well.
How can we apply this patch? Sorry for such a noob question...
marcus6999 said:
How can we apply this patch? Sorry for such a noob question...
Click to expand...
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If you are not building your own kernel, there will hopefully be a few kernels in this section that will include this.
If you are building your own kernel, you can take the posted 'smb345-charger.c' and replace 'drivers/power/smb345-charger.c' in your kernel tree. It's based on the stock kernel.
tni.andro said:
This is very different. It isn't supposed to increase battery runtime, it's supposed to decrease it.
It allows allows to not completely charge the battery. In return, the battery won't deteriorate as quickly. Making up numbers here: if the battery would normally survive 300 charge cycles (charged to 4.3V); if you only charge to 4.2V (or about 93% capacity), the battery would last for 600 charge cycles before it's dead.
Click to expand...
Click to collapse
Most kernels on all my phones have ability to set precisely the % you want battery charged up too. Haven't seen it for flo/razor
Sent from Pimped N7 (2013) XDA PREMIUM
Hmm that's a good suggestion. Truly to increase the battery charge cycle life by almost 2x you just have to charge it until 90%.
So basically you don't charge it to max voltage and you don't let the charger begin the high voltage stabilization.
So with normally (good Lithium batteries these days) 500 charge cycles you go for 1000 and so on.
I was searching for something like that, because it's a tablet that can last through many years.
I think it's a great feature and all kernels should implement and have it at stock. And let the user decide and choose voltage with an easy script if he wants it.
Battery life year extender
Thank you
tni.andro said:
If you are not building your own kernel, there will hopefully be a few kernels in this section that will include this.
If you are building your own kernel, you can take the posted 'smb345-charger.c' and replace 'drivers/power/smb345-charger.c' in your kernel tree. It's based on the stock kernel.
Click to expand...
Click to collapse
I'm going to add this in the next update to ElementalX
CTCaer said:
Hmm that's a good suggestion. Truly to increase the battery charge cycle life by almost 2x you just have to charge it until 90%.
So basically you don't charge it to max voltage and you don't let the charger begin the high voltage stabilization.
So with normally (good Lithium batteries these days) 500 charge cycles you go for 1000 and so on.
Click to expand...
Click to collapse
There is no good reason to use battery percentage to terminate the charge, instead of using a lower charger float voltage. Likely the only reason a percentage cutoff was used in other cases is that the charger chip didn't support setting the voltage.
The voltage setting is also much more predictable - the battery gauge can be quite unreliable in terms of charge estimate and easily jump 10% when it recalibrates itself.
Can anyone post the source of info for 2x battery cycle if only charge up to 4.2v? I read that not charging lithiums to full charge can help extended life but never seen anyone give estimates like 2x at 4.2v and 4x for 4.1v. Estimates seem a bit high to me. I agree with others here that this tablet can last a few years if the battery holds up so I was planning on replacing the battery after a year or two but if lowering the battery voltage really works this well then I will try it. There is a pretty big downside of having almost 10% less battery life all the time.
neotekz said:
Can anyone post the source of info for 2x battery cycle if only charge up to 4.2v?
Click to expand...
Click to collapse
http://batteryuniversity.com/learn/article/how_to_prolong_lithium_based_batteries
http://macomp.ru/wp-content/uploads/2012/04/1607542.pdf
http://www.eetasia.com/STATIC/PDF/200806/EEOL_2008JUN16_POW_TA_01.pdf
tni.andro said:
There is no good reason to use battery percentage to terminate the charge, instead of using a lower charger float voltage.
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Click to collapse
Of course there is. The last 10% to 20% are causing the most aging of a lithium ion battery.
If you really want to prolonge the live of your battery charge it only up to 80%.
There is no real reason to limit the voltage as the stock hardware and drivers handles this already really good by adopting the charging voltage dynamically.
There's no reason to change charger's voltage. The only thing there's meaning in changing in the charger side is output current.
For example with the size of Nexus battery you can use a 1A one or 800mA. It will charge slow but you can maintain some more charge cycles.
Still the most important is to not let the battery reach it's maximum voltage (100%) and let the charger do it's voltage stabilization.
As also said from others before that's what takes the battery charge life away.
The best for good juice and year protection is 90%.
The best for year extension and low juice is 60%.
And of course, when you really need 100% juice (trip, flight, beach, whatever) you just charge it full and don't care for some cycles.
Good batteries have -+500 Full charge cycles. So almost one and a half year if you go from 100->0->100 everyday, before the capacity (mAh) of battery drops.
tni.andro said:
There is no good reason to use battery percentage to terminate the charge, instead of using a lower charger float voltage.
Click to expand...
Click to collapse
TDO said:
The last 10% to 20% are causing the most aging of a lithium ion battery.
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That's correct.
If you really want to prolonge the live of your battery charge it only up to 80%.
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That's exactly what lowering the charger float voltage can do. The original post has numbers for different voltages. E.g. with a 4.1V charger float voltage, the charger will stop charging at 83% charge.
There is no real reason to limit the voltage as the stock hardware and drivers handles this already really good by adopting the charging voltage dynamically.
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Click to collapse
The stock driver sets the charger float voltage to 4.3V. Given that there is current limiting (1200mA input current limit), the voltage will be lower initially, but the voltage regulation is 4.3V once the current is low enough.
Like I mentioned, using the battery percentage as cutoff isn't great, since the battery gauge can be pretty inaccurate (can be off by >10%). Setting the float voltage lower results in the same charge cuttoff every time, even if the battery gauge makes an inaccurate estimate.