Here is some information that should be useful to everyone in one way or another if not then you should have told us your secret months ago. lol
A Li-ion batteries life is on a time clock from the day it's produced and how it is used, maintained and the number of cycles it goes through reduces it's life. Even when not being used at all the clock is ticking and life is shortening.
So if any of you are like me I know many of you are far worse than me when it comes to the amount of stress put through it with flashing and extreme general use. Hopefully this will shed some light for us as to what we can do to try and prolong the life of our batteries.
The majority of the following information is from the book “Batteries in a Portable World – A Handbook on Rechargeable Batteries for Non-Engineers” (2nd edition) and Battery University™
Special thanks to the books author and sponsor of Battery University™,
Isidor Buchmann
CEO and Founder, Cadex Electronics Inc.
How to Prolong the Life of Li-ion Batteries
Battery wear-down on lithium-based batteries is caused by two activities: actual usage or cycling, and aging. The wear-down effects by usage and aging apply to all batteries but this is more pronounced on lithium-based systems.
The Li-ion batteries prefer a shallow discharge. Partial discharges produce less wear than a full discharge and the capacity loss per cycle is reduced. A periodic full discharge is not required because the lithium-based battery has no memory. A full cycle constitutes a discharge to 3V/cell. When specifying the number of cycles a lithium-based battery can endure, manufacturers commonly use an 80 percent depth of discharge. This method resembles a reasonably accurate field simulation. It also achieves a higher cycle count than doing full discharges.
Simple Guidelines
Charge the Li-ion often, except before a long storage. Avoid repeated deep discharges.
Keep the Li-ion battery cool. Prevent storage in a hot car. Never freeze a battery.
Avoid purchasing spare Li-ion batteries for later use. Observe manufacturing date when purchasing. Do not buy old stock, even if sold at clearance prices.
Hints to long battery life
3.92V/cell is the best upper voltage threshold for cobalt-based lithium-ion. Charging batteries to this voltage level has been shown to double cycle life. Lithium-ion systems for defense applications make use of the lower voltage threshold. The negative is reduced capacity.
The charge current of Li-ion should be moderate (0.5C for cobalt-based lithium-ion).The lower charge current reduces the time in which the cell resides at 4.20V. It should be noted that a 0.5C charge only adds marginally to the charge time over 1C because the topping charge will be shorter. A high current charge tends to push the voltage up and forces it into the voltage limit prematurely.
Memory Myth or Fact?
Lithium batteries are not affected by memory, but the chemistry has its own peculiarities. Current inhibiting pacifier layers affect them through plate oxidation. This degenerative effect is non-correctable on a lithium-based system
Calibration
A more serious issue is maintenance requirements, better known as capacity re-learning. This procedure is needed on a regular basis to calibrate the battery.
Why is calibration needed?
The answer is in correcting the tracking errors that occur between the battery and the digital sensing circuit during use. The most ideal battery use, as far as fuel-gauge accuracy is concerned, is a full charge followed by a full discharge at a constant 1C rate. This ensures that the tracking error is less than one percent per cycle. However, a battery may be discharged for only a few minutes at a time and commonly at a lower C-rate than 1C. Worst of all, the load may be uneven and vary drastically. Eventually, the true capacity of the battery no longer synchronizes with the fuel gauge and "a full charge and discharge are needed to ‘re-learn’ or calibrate the battery."
How often is calibration needed?
The answer lies in the type of battery application. For practical purposes, a calibration is recommended once every three months or after every 40 short cycles.
What happens if the battery is not calibrated regularly? Can such a battery be used in confidence?
Such a battery is able to function normally, but the digital readout will be inaccurate. If not corrected, the fuel gauge information simply becomes a nuisance.
Just Tell Me WTF I Should Do!
Charge your battery as often as possible, partial discharges are actually better for your battery
Once your battery is charged to 100% avoid leaving it plugged in any longer if you are not using a OEM charger.
Your battery should never get hot from charging if it does this is a sign it may be damaged.
If fuel gauge starts acting up calibrate your battery.
Yeah but how the f^$% do I calibrate my battery?
Charge phone up and then delete your battery stats.
Unplug your phone from your wall charger and let your battery drain all the way down until phone shuts off.
While still off charge phone to 100% and then boot up as normal.
There is so much more that it's mind boggling but I think this covers the main parts and beyond for everyone. So far it appears that the bump method is not necessary nor are the numerous other steps.
I can only laugh when I think that the reason the method of calibration I was using was actually working is due to the fact that the "wipe batt stats, drain battery completely and charge to 100%" is basically the last step and all that is essentially needed.
3 hours? That's it? I thought whenever I charged from empty to full when it's off it's longer.. I should time it.. hmm
darkamikaze said:
3 hours? That's it? I thought whenever I charged from empty to full when it's off it's longer.. I should time it.. hmm
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Click to collapse
I removed the time completely since some may vary. But the 3 hours is how long it should take to charge on a standalone battery charger. So rather than confuse or have questions it's better without it.
Nice work!
Charging a 1500mAh battery at 500mAh for example will take 3 hours. The Captivate charges at 2 levels though depending on if it's USB (500mAh max for charge + phone use) or a charger (whatever it says on the charger up to ~1200mAh) so it can probably get done in under 2 hours.
The phone charges to 4.23V and stops charging when full but continues to run on external power, and shuts down at 3.500V where it only consumes current to monitor the power button.
Just for reference.
Battery Stats
Since this is the first time i had a really good battery life. I would like to share it with everyone. Please see the attached screen shots.
I am using Darky's 9.1 with SuckerPunch's 1280/500 Kernel and TLJL3 modem.
I hope this will help anyone trying to get more battery life out of their Captivate.
Thanks,
CuriousTech said:
Nice work!
Charging a 1500mAh battery at 500mAh for example will take 3 hours. The Captivate charges at 2 levels though depending on if it's USB (500mAh max for charge + phone use) or a charger (whatever it says on the charger up to ~1200mAh) so it can probably get done in under 2 hours.
The phone charges to 4.23V and stops charging when full but continues to run on external power, and shuts down at 3.500V where it only consumes current to monitor the power button.
Just for reference.
Click to expand...
Click to collapse
Thanks Curious appreciate it and thanks for the additional info.
I had some other random thoughts about the calibration because I keep seeing so many posts daily.
For example "I installed a new kernel 15 minutes ago, recalibrated and the battery drain is horrible." or "After a few charges it lasted longer."
I don't think people get the idea of calibration. Recalibrating determines the capacity of the battery to convert to a % full gauge. To do that you need to fully charge until the "Battery full. Unplug charger." notification, and not rely on the display and unplugging as soon as it hits 100%. That's the inaccurate display that you're trying to calibrate.
Think of it like having an opaque container and a teaspoon. You think the container can hold 100 teaspoons, so you stop filling at 100. All you can get out of it is 100 until you try to fill until it tops off and then count how many come back out.
The phone works the same way. It has an ammeter that monitors the charge current and drain current from the battery from the time you unplug it until it shuts off and remembers that total as the capacity. Unless it's recharged in the middle which voids the data.
After that full discharge, it should stay pretty accurate even with partial discharges. At least until the next rom/kernel flash which wipes it out. At that point (I assume) it uses a simple voltage level and some relative amps drawn to display the gauge, instead of the smarter method of keeping a constant value of mAh by adding when charging and subtracting when draining to know exaclty how full the battery is.
CuriousTech said:
Nice work!
Charging a 1500mAh battery at 500mAh for example will take 3 hours. The Captivate charges at 2 levels though depending on if it's USB (500mAh max for charge + phone use) or a charger (whatever it says on the charger up to ~1200mAh) so it can probably get done in under 2 hours.
The phone charges to 4.23V and stops charging when full but continues to run on external power, and shuts down at 3.500V where it only consumes current to monitor the power button.
Just for reference.
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Click to collapse
hm. so if the phone switches to external power when the charge is full, is it okay to leave my phone plugged in once it's done charging? or is it just the fact that the battery is holding a full (4.2V) charge for a long time that's bad for its health?
in any case, useful post! i knew there were ways to preserve the life of li-ion batteries, but was never well-versed on the details.
Yes to both. Once the battery is fully charged, the charge circuit stops completely. It doesn't even need to trickle charge, so leaving it plugged in doesn't hurt anything.
Once the charge is complete the voltage isn't being held at 4.20V so it can come back down a little. I think BatteryUniversity generalizes becuase there have been many different designs over the years that weren't as good as what we have now, and some may have trickle charged their Li-Ions which shortens the life.
Which is it that wipes the battery stats, ROM or kernel? or is it both?
CuriousTech said:
Yes to both. Once the battery is fully charged, the charge circuit stops completely. It doesn't even need to trickle charge, so leaving it plugged in doesn't hurt anything.
Once the charge is complete the voltage isn't being held at 4.20V so it can come back down a little. I think BatteryUniversity generalizes becuase there have been many different designs over the years that weren't as good as what we have now, and some may have trickle charged their Li-Ions which shortens the life.
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Click to collapse
One word of caution though is to ensure that you are using an OEM charger. Battery University recommends that you unplug once capacity is reached but perhaps this is a general statement for Li-ion batteries as you state.
zerkai said:
Which is it that wipes the battery stats, ROM or kernel? or is it both?
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Click to collapse
Both. The first thing in a ROM flash script is to format all the partitions, so that means the batterstats.bin file is erased. When flashing a new kernel the file gets reset by some other means. No idea what. It could be CWM.
Yeah but how the f^$% do I calibrate my battery?
Charge phone up and then delete your battery stats.
Unplug your phone from your wall charger and let your battery drain all the way down until phone shuts off.
While still off charge phone to 100% and then boot up as normal.
My noob question is, how do you delete the battery stats?
iNFRiNGE said:
One word of caution though is to ensure that you are using an OEM charger. Battery University recommends that you unplug once capacity is reached but perhaps this is a general statement for Li-ion batteries as you state.
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Click to collapse
What happens when you introduce the variable of occasional car charger use?
Sanctus Peregrinus said:
Yeah but how the f^$% do I calibrate my battery?
Charge phone up and then delete your battery stats.
Unplug your phone from your wall charger and let your battery drain all the way down until phone shuts off.
While still off charge phone to 100% and then boot up as normal.
My noob question is, how do you delete the battery stats?
Click to expand...
Click to collapse
the file is located at /data/system/batterystats.bin . you'll need a file browser with root access (i use root explorer, a paid app). make sure you mount the storage as read/write or you won't be able to delete the file.
after that, reboot your phone and it will rebuild the batterystats file.
***disclaimer: be careful doing this. if you delete a crucial file, you risk messing up or bricking your phone. such is life.
Nice write up with alot of interesting information. I have never calibrated my battery but will have to try it out. Thanks for posting.
Sent from my SAMSUNG-SGH-I897 using XDA App
I'm not positive of this, but I don't think batterystats.bin holds any battery capacity or health info. I was looking at BatteryManager and it looks like a database of processes and what they use only. But there is info somewhere that gets lost easily, which is the capacity and current amount consumed.
I've been skipping the delete of that file (using CWM) and have noticed that it recalibrates fine anyway. This coming from the point of dropping just after unplugging, which is a good indication that the info is gone.
It doesn't matter if you use a car charger, USB, or AC. The phone has the actual smart charger in it, the external connection is just the power supply. The chip inside regulates and monitors the charge.
So think of it this way. The charger knows when the battery is empty or full, and measures what goes in and comes out. So to know the capacity, it has to go from full to empty. That's really all there is to it. Just wait for the real "Battery full" before unplugging.
Related
Firstly.... go here and read this -
http://batteryuniversity.com/learn/article/charging_lithium_ion_batteries
The battery is fully charged when it is at 4.2 Volts and fully discharged at some predefined voltage (Lets say 3 volts).
The phone can measure these voltages directly from the battery. To see the voltage of your battery type *#*#4636#*#* into your phone and go to battery information.
If all that is so then what is the point or need of "recalibrating" and deleting battery stats and all that.
It seems logical to me that battery stats is just the place where your battery usage history is stored and nothing else.
Can someone confirm this or convince me otherwise?
(I rotate between 3 batteries and cannot grasp the idea that my phone can't consistently measure the charge level of the battery and operate accordingly.)
Measuring the Voltage to get the charge level is not very accurate, and has to be done with no load on the battery (that is, when its not in your phone).
So the phone has to count "energy used from"/"energy stored in" the battery for an accurate display. (called "Coloumb counter")
Did some test
I did a test on new a battery a while ago. Measure voltage when the battery completely empty and fully charged.
Empty battery
1% remaining, using SystemPanel
Take the battery out and measure it with Multimeter
Fully charged
100% charged
Again, measure it with Multimeter
The voltage showed on the phone using SystemPanel app is quite accurate with 0.04V margin of error. Most smart electronic measure lithium battery capacity according to the remaining voltage. In this case, fully charged SGS is 4.2V, empty is 3.5V.
Me too, don't know why we have to delete batterystats.bin to recalibrate battery indicator But I do know that SGS keep track on power consumption on each of its component/application. Its a little bit silly if SGS reads batterystats.bin and display it as battery indicator.
Yet again how is this android development.
Sent from my GT-I9000 using XDA App
xufos said:
I did a test on new a battery a while ago. Measure current when the battery completely empty and fully charged.
Empty battery
1% remaining, using SystemPanel
Take the battery out and measure it with Multimeter
Fully charged
100% charged
Again, measure it with Multimeter
The current showed on the phone using SystemPanel app is quite accurate with 0.04V error margin. Most smart electronic measure lithium battery capacity according to the remaining current. In this case, fully charged SGS is 4.2V, empty is 3.5V.
Me too, don't know why we have to delete batterystats.bin to recalibrate battery indicator But I do know that SGS keep track on power consumption on each of its component/application. Its a little bit silly if SGS reads batterystats.bin and display it as battery indicator.
Click to expand...
Click to collapse
Thanks for that, but you were actually measuring the Voltage, not current (Amperes).
In any case, for laptop Li-ion batteries there is normally a capacity counter (Coulomb counter) that reports the capacity in terms of mAh (milli-ampere hours). It can normally report the remaining capacity, maximum capacity, design capacity, and can be used to measure the *actual* power drain (in terms of Watts).
I wonder if Android has APIs that let apps access that kind of information?
Not really sure about this, but:
Phone seems to measure both voltage & discharge speed, "predicting" remaining charge.
It happens that after a flash battery indicator jumps to a higher value (not compatible with the couple of minutes of dc connection it had), and fall to a way too low value after any battery intensive task (a few minutes of audio call are enough), once more not compatible with the real usage.
I should inspect android code to be shure of this, but I suspect batterystats.bin is used to keep track of battery usage and to this sort of prediction, while a firmware flash seems to mess somehow the measurement.
Edit: this is based on my direct experience, even if on just "empirical" tests. I'll take a look to code asap
'mkay, battery talk... always interesting to see what people make of this.
Let's help out all the misunderstandings here and start with the basics
First of all: read the basics on Li-ion batteries:
http://electronics.howstuffworks.com/lithium-ion-battery.htm
second:
you DON'T measure your voltage when your battery is disconnected. Because it will rise to the normal values of the battery after a while. When you connect it, and use it, the voltage will lower. Compare it to a garden hose. if you let water run out, the presure drops and water starts flowing (presure is voltage, flowing is the current). If you measure the presure when there is no water running, the presure will always mount to the default value, even if there is "not much water left in the tank". But when it starts running again, it could very well run out very fast. So in comparison: voltage says something, but only when you "use" it.
Third:
When a battery ages, it's characteristics change, it will be full... and then all at once, empty. It's not linear. So calculating the capacity is always a bit "guessing". (compare it to stones in your water tank... they don't give you water, the tank doesn't change, but all of a sudden, you're out of water).
conclusion:
capacity of a battery is a very tricky thing to do, it's a combination of voltage, current, age... so the best way to determine capacity is by using the history of the battery as the "guide" to the future. Resetting the battery statistics will remove that history and your phone will have to "learn" it's behavior again. If you don't reset your stats, your values will become more reliable over time (depending of course on the time the stats are kept )
For those who speak dutch, i put a complete battery description/howto/misunderstandings post on www.modelbouwforum.nl (search for posts of "harrydg")
If there are more questions or so, just ask, i'll try to help out as much as possible...
wow harrydg that's great explanation, wish you were my physics teacher back in high school
someone add this post to the main FAQ!
I just wanna write it in a simpler way:
You've access to the battery stats from the kernel. And of course its current consumption which is measured not voltage. Voltage doesn't tell all that much. During high draws your voltage (at the battery level) can fluctuate quite a bit.
There's a regulator (or probably a bunch of them) get a stable voltage no matter what the input voltage is (well, still it has to be in the 3.3/5v range probably else the regulator burns)
Anyway, that's also why the battery stats have to be calibrated, while you can measure how much current is used (in maH aka milli amp per hour, or in mA aka "instant" milli amps), you don't know the battery capacity.
Not only the battery capacity changes from battery to battery but it also changes during the life time of the battery.
The *only* way to calibrate the battery, is to delete the stats, have a fully charged phone and let it drain out the battery until it turns off. That way the kernel will measure for example 1457mah used until it ran out of juice, and that's your battery capacity then. Having the full capacity allows the kernel to give you a rather precise estimate of your current battery status (eg "80%" that you see on the top of the screen) (of course the actual calculation is a bit more complicate but that's the basics)
If calibration stats storage is changed for any reason (probably kernel upgrade or just a whacky samsung implementation that gets corrupted for some reason) you need to delete it and make a new one to recalibrate.
If you want to make it simpler, make it at least correct...
"Anyway, that's also why the battery stats have to be calibrated, while you can measure how much current is used (in maH aka milli amp per hour, or in mA aka "instant" milli amps), you don't know the battery capacity."
First of al, it's mAh, which means milli ampere hour, NOT per hour, that would be mA/h, which it is not.
mA is milli ampere, which is a current
there is a significant difference between the 2.
the first is "capacity"
the second is "current"
it's like a bottle. The capacity is 2l and you pour at 1l per minut...
so... make it simple please...
My guess is, that android is measuring the known min and max by the battery reported values, stores them and calculates the percentages.
So it is device and battery independent.
harrydg said:
If you want to make it simpler, make it at least correct...
"Anyway, that's also why the battery stats have to be calibrated, while you can measure how much current is used (in maH aka milli amp per hour, or in mA aka "instant" milli amps), you don't know the battery capacity."
First of al, it's mAh, which means milli ampere hour, NOT per hour, that would be mA/h, which it is not.
mA is milli ampere, which is a current
there is a significant difference between the 2.
the first is "capacity"
the second is "current"
it's like a bottle. The capacity is 2l and you pour at 1l per minut...
so... make it simple please...
Click to expand...
Click to collapse
Sorry a typo and no caps deserve heavy flaming
bilboa1 said:
Sorry a typo and no caps deserve heavy flaming
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Click to collapse
hehe, sorry for the rant, but if you want to put it simple, make sure the terminology and abbreviations are correct. If not, people will take over the mistakes and conversations will go totally wrong because of misunderstandings...
Thanks very much for the feedback guys. It makes more sense now.
It's using batterystats to get familiar with discharge rates in order to give an accurate estimation of remaining charge and a prediction of when it will run dry.
Can it misreprasent these values and forcibly power down the phone when there is still charge remaining?
And likewise can it stop the charging process prematurely, estimating the battery to be at 100% charge when it is lower?
Is this the reason to recalibrate?
Heres one thing what I noticed about the battery stats, some say deleting it fixes the guage and does not really recalibrate the battery, I really doubt there is a way for end users to do that, even if you never delete the battery stats bin and your drain is pretty fast, it significantly slows down when your battery hits around 25~35, the lower the power on the battery the more accurate it can be represented regardless of the calibration. This is applicaple for the SGS only.
Now it comes to the question..
If the phone create battery stats every time the phone reboot, then when is the best time to delete and the best way to calibrate?
This is what I normally do..
..delete stats at 5%, let it run dry til it turn itself off, dont turn on but connect the charger til it fully charged. Turn phone on and ill have fully charged battery along with fresh stats.
Is this correct?
vosszaa said:
Now it comes to the question..
If the phone create battery stats every time the phone reboot, then when is the best time to delete and the best way to calibrate?
This is what I normally do..
..delete stats at 5%, let it run dry til it turn itself off, dont turn on but connect the charger til it fully charged. Turn phone on and ill have fully charged battery along with fresh stats.
Is this correct?
Click to expand...
Click to collapse
On the SGS theres no real point in deleting it, unless you dont really wanna see the battery go down to 35% and stay there for a while, how ever busted your battery indicator is it gets very accurate as the lower it goes.
I never found batterystats made any difference. What did make a difference is the rom or kernel, what widgets, lagfix e.t.c
If you get more than 1% battery drain per 5hr standby then something is wrong
Sent from my GT-I9000 using XDA App
android53 said:
I never found batterystats made any difference. What did make a difference is the rom or kernel, what widgets, lagfix e.t.c
If you get more than 1% battery drain per 5hr standby then something is wrong
Sent from my GT-I9000 using XDA App
Click to expand...
Click to collapse
I find that conclusion quite flawed.
First of all, what's your definition of standby?
3g on? Wireless on? Autosync on? There are also noticeable differences between different firmwares and between 2.1 and 2.2.
In addition, most people are reporting somewhere around 1% per 1 hour standby or 1% per 2 hour standby, which it what I have been experiencing as well. Sometimes, apparently for no reason, it can drain faster than that, maybe 1% per 0,5 hour or more. I think this might be some widgets fault.
1%/5h standby 3g no sync
i get 1%/2h with data and sync
Depends on your reception, im just basically saying if your losing say 8% battery overnight or more then something is wrong unless your polling several push email accounts
Hello everyone
I was wondering if its ok to leave the transformer connected to the charger.
Is it like the Evo with trickle down when it reaches 100%
I dont want to over charge it. If it were my laptop i would disconnect the battery at full charge. But its not possible to do that with the transformer.
I want to keep my cycle count low and prevent over charing.
I also wonder what happens in a few years when the battery is shot...
Charging is what damages Li-Ion batteries... I'd recommend not keeping it on the charger all the time. Android will purposely not keep the battery at 100% to help avoid some damage.
Li-ion prefer to be around 20-80% charge.
When battery is 100% and you keep the charger connected, heat will begin to build up and eventually you will kill your battery.
I'd do as with a notebook: charge till 100%, then remove battery or charger (in case of the tablet charger ) . Then use your tablet and recharge when needed / desired. And from time to time a full charge / discharge cycle won't do any harm.
Just my 2 cents.
Regards.
These tablets don't automatically recognize when it's fully charged and turn off the charging?
Ravynmagi said:
These tablets don't automatically recognize when it's fully charged and turn off the charging?
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Click to collapse
They do. There are other threads asking why thier TF's don't show 100% when unplgged from the charger. Same as it does on my Evo.
I think pretty much every modern device recognizes a full charge and responds accordingly. In fact, MacBooks will throttle performance if the battery ISN'T kept in while the system is running on A/C.
Heat will damage a battery, but it's not heat from charging but heat from operation. If a notebook is poorly designed and the battery is near a heat source, then removing the battery might be a good idea (except with the aforementioned MacBooks), but that's independent of the charging issue.
I think it's fine to keep it plugged in. These devices are smart enough to manage such things. Of course, the TF's charging cable's so short it's hard to use when plugged in, but that's a different issue entirely.
CalvinH said:
When battery is 100% and you keep the charger connected, heat will begin to build up and eventually you will kill your battery.
I'd do as with a notebook: charge till 100%, then remove battery or charger (in case of the tablet charger ) . Then use your tablet and recharge when needed / desired. And from time to time a full charge / discharge cycle won't do any harm.
Just my 2 cents.
Regards.
Click to expand...
Click to collapse
From what I understand this process cannot and will not kill the battery. This did happen in the old type of batteries with the ,emory effect but these new batteries and the OS's management system for charging does not allow the battery to be killed.
it will heat up and that would happen as there is a flow of electricity but not to a level that would kill the battery.
Cheers
IS it normal to go from 4% battery to 99% in under 3 hours ?
I thought this was supposed to take 8 hours to charge.
Cheers,
gpearson1968
gpearson1968 said:
IS it normal to go from 4% battery to 99% in under 3 hours ?
I thought this was supposed to take 8 hours to charge.
Cheers,
gpearson1968
Click to expand...
Click to collapse
Yes that's normal. It's meant to take about 3hrs.
Thanks guys...
Still dont know about it. Because I think its like my EVO and technology got so good that my battery is protected.
I really dont want my transformer to become a expensive paper weight or non-mobile because after a few years it has 45 mins battery life.
I've got the first full charge and full depletion done. Is it ok to use while charging now as long as I fully charge and fully deplete it a couple more times?
error12 said:
Thanks guys...
Still dont know about it. Because I think its like my EVO and technology got so good that my battery is protected.
I really dont want my transformer to become a expensive paper weight or non-mobile because after a few years it has 45 mins battery life.
Click to expand...
Click to collapse
batteries will degrade over time....would you be keeping this tablet for over 2-3 years? a simple battery change could work if ever needed
I am no expert, but I have spent some time searching around the internet looking for information on the best methods for improving the life of a battery. Most of the information I have found said it is bad to completely discharge a Li-polymer battery. The articarles stated it was best to charge the battery when it reaches 20% to avoid shortening its life.
Sent from my DROIDX using XDA App
Batteries are like muscles - they like to be exercised.
Leaving the unit plugged in WILL NOT HURT YOUR BATTERY. Period. The charging circuitry in modern devices is smart enough to cut current to the battery once it has reached a certain level of resistance.
Batteries do not like being deeply discharged. Most devices will shut off before the battery gets too deeply discharged, but it's never a good idea to tempt fate by running it until the device shuts off.
What really determines a battery's life is the number of cycles it has been put through. A cycle would be a full charge followed by a full (or to a lower end threshold) discharge.
The old original Lithium Ion batteries used in laptops would usually last about 300 full cycles or so - about a year if you used it on the battery every day. Partial discharges of course only count as fractions of a cycle.
Given the life of these types of devices, considering we'll likely upgrade to the next big thing in a year or so, I don't think anyone here will come close to 'wearing out' a battery.
EMINENT1 said:
I've got the first full charge and full depletion done. Is it ok to use while charging now as long as I fully charge and fully deplete it a couple more times?
Click to expand...
Click to collapse
As stated, these are Li-Ion batteries, and they do not need to be trained. The only reason you might need to do any training is to calibrate Android's understanding of the battery (although I doubt you need to do a full discharge for that, either).
It's not going to suddenly kill it, but it will over time hurt your battery's life.
I went ahead and did a full discharge/charge cycle, but only because Asus said to do so in the manual. Maybe the copywriter just copied/pasted from a circa 1990's manual for a device with a NiCd battery, but I figured if they're suggesting it, I might as well do it.
One of the things I have noticed scouring the internet for tips on battery life prolongation, is that you end up with lots of contradictory advice coming from unreferenced (and often, unresearched) sources. (Note that by 'prolonging', I mean both prolonging the current battery cycle, and also, how to prolong the battery in the long term).
One big question is how you should be recharging it. For example:
Do you let the battery go down low, and then recharge it back to full?
Do you only do partial discharges, and always keep the battery topped up?
When available, is it better to work plugged in?
There are two helpful articles, both from the Battery University, which seems reliable and they have nice experimental data.
[1] Charging lithium batteries
[2] How to prolong lithium batteries
From what I gather, the answer to the above questions are as follows:
Full discharges will reduce the number of recharge cycles in your battery. For example, going to 100% discharge only gives a battery with 500 discharges, while going to 10% discharge gives a battery with 4700 discharges. Note that this advice contradicts other 'unreferenced' sources, like here:
Change your charging pattern: Most of us have the habit of charging the phone quite often even when the phone has enough battery left on it. It’s always better to leave the battery to discharge completely to say like 20% and only then recharge it. This way your battery will not only also last longer but also has longer life.
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It is better to note recharge to full
Li-ion does not need to be fully charged, as is the case with lead acid, nor is it desirable to do so. In fact, it is better not to fully charge, because high voltages stresses the battery. Choosing a lower voltage threshold, or eliminating the saturation charge altogether, prolongs battery life but this reduces the runtime. Since the consumer market promotes maximum runtime, these chargers go for maximum capacity rather than extended service life.
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However, I admit that this is a fairly PITA rule to implement. It would be impractical to always charge only to, say 80%. I think this rule, in practice, advises against charging all the way to 100% because then your charger may put in the topping charge (how many chargers do this?)
It is better to not leave devices plugged into wall charges.
Some portable devices sit in a charge cradle in the on position. The current drawn through the device is called the parasitic load and can distort the charge cycle. Battery manufacturers advise against parasitic load because it induces mini-cycles. The battery is continuously being discharged to 4.20V/cell and then charged by the device. The stress level on the battery is especially high because the cycles occur at the 4.20V/cell threshold.
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A portable device must be turned off during charge.
This allows the battery to reach the set threshold voltage unhindered, and enables terminating charge on low current. A parasitic load confuses the charger by depressing the battery voltage and preventing the current in the saturation stage to drop low. A battery may be fully charged, but the prevailing conditions prompt a continued charge. This causes undue battery stress and compromises safety.
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This, however, spawns two further questions:
What about USB charging? Because USB charging is slower (due to a lower amperage), is there any advantage to working with your tablet plugged into a USB drive? Is this better than discharging the battery?
I work with my laptop plugged in all the time. Partly, there is nothing I can do about it (Macbooks no longer allow easy removable of the battery). This means that on top of the heat degrading the battery, one must contend with the battery contunually being charged. What are the safeguards in place? I would imagine a smart charging system would lower the voltage and amperage when a laptop is plugged in.
I remember when I used a iPhone that one cycle includes partial charges and discharges like if you charge 10% and then another 20% and so on you ad those until you get 100% of a cycle, this was according to apple. That's why you can get your battery dead in one year and half (since they promises 450ish battery cycles )
Inntresting reading...
Sent from HTC Sensation, Elegancia ROM Series....
Hey, thanks for this, man. Good tips. I don't want to go abusing the batteries of all those shiny new Christmas gadgets.
Thanks very useful tips
Yes for li-ion you never want it to fully discharge.
Rift
I like the research you did here very nice. I have an EVO and that thing can't hold a charge for anything. I have like three batteries (two that come with wall chargers) just so I know I'm not going to run out of juice when I need it. I could leave everything off like mobile data, wifi, etc but then why do I have a fancy smancy phone then to begin with I want to use the damn thing. The battery is my only real issue I have with this magnificent phone. Thanks for taking the time to do some research on the subject.
Thanks for the tips. Battery is important than CPU now as for UX is concerned.
battery management
i found the battery manager from Market Place really useful for my I9000 Galaxy S on ICS
thanks for the good information
Thanks for this news
If your worried about power "cleanliness" you could always get a power conditioner to guarantee level output.
Now with batteries being able to be replaced easy enough (droid user) and with in my price point I don't give it too much thought.
Thanks for the great info, should be a big help
Glad I have insurance.... battery dies, they give me a new one!-
3G or 2G
Had someone checked, if using 2G instead of 3G giving the much better battery life?
If you are asking if you get more battery life with 2G than 3G, I think it's the same. The battery life should be less if you have the option "use 2G/3G preferred" because the phone searches simultaneously for 2G and 3G frequencies
Now that you bring that up, has anybody compared 3g to 4G battery life?
Thanks for the tips. It really does get confusing when coming to batteries.
Thank you for the advice
i agree...and have found this all true in my own studys and doings
I read that a battery will last longer if you don't let it get below 40%, and full discharges are bad for the longevity. Is this true? Here is a good read on the subject. http://batteryuniversity.com/index.php/learn/article/how_to_prolong_lithium_based_batteries
Jspeer said:
I read that a battery will last longer if you don't let it get below 40%, and full discharges are bad for the longevity. Is this true? Here is a good read on the subject. http://batteryuniversity.com/index.php/learn/article/how_to_prolong_lithium_based_batteries
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that is true. the affect is probably minimal though(like we probably lose .7% of our battery per month if dont let it get low before charging it, instead of the typical 1% per month)
i get through half of my day with about 50% battery less, sometimes more. so i've made it a habit of charging it once i see it's around this 50% mark.
Jspeer said:
I read that a battery will last longer if you don't let it get below 40%, and full discharges are bad for the longevity. Is this true? Here is a good read on the subject. http://batteryuniversity.com/index.php/learn/article/how_to_prolong_lithium_based_batteries
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The effect is accelerated/more pronounced below 20%...
Here is the good thing though... These phone's minimum operating voltage is higher than the minimum voltage of a Li ION battery. Using standard battery life measurements, the 0% according to the phone, is about 20% of standard.
Should you do a full discharge every now and then in order to calibrate the battery? I haven't been able to find a definitive answer on this in other related threads. Some say you should, some say it's not necessary since the battery doesn't have memory cells. I have never let my battery get below 50% and everything seems to work fine but it does seem to make sense to do a full discharge from time to time so the battery knows its capacity.
Jspeer said:
Should you do a full discharge every now and then in order to calibrate the battery? I haven't been able to find a definitive answer on this in other related threads. Some say you should, some say it's not necessary since the battery doesn't have memory cells. I have never let my battery get below 50% and everything seems to work fine but it does seem to make sense to do a full discharge from time to time so the battery knows its capacity.
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Li-ON battery's do not need to be calibrated. that was only with old battery tech such as Ni-Cad or NIMH
I let mine get low all the time I use my phone a lot. Hopefully its not to expensive to replace battery since Google thinks that replacing a battery is to complicated for us tech savvy people
Justice for Kelly Thomas RIP
I don't worry about it. I charge it overnight. If I've over used it in the day and I feel it will die before bed, i'll top it up but not to protect the battery. Just to ensure I can use my phone.
If they wanted you to do anything special with charging / draining, it would be in the instructions
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markdapimp said:
Li-ON battery's do not need to be calibrated. that was only with old battery tech such as Ni-Cad or NIMH
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The battery itself does not but occasionally the controller needs a kick in the pants. Deep drains on li-ion should be avoided at all costs. The phone hasn't been out long enough to even think about the sort of problem. But after a couple hundred charges you might see a behavior that will be corrected by one full discharge.
Its not uncommon to see cases where you actually replace the cell behind a controller and the controller not picking up the change in capacity. Never in cell phones mostly laptop battery rebuilds etc but it exhibits an idea of what happens. The battery controller takes note of the original, current maximum and current charge capacity. Not sure how I suppose voltage versus read amp hours. But as a battery gets old you might start seeing the maximum capacity reading fluctuate. But if at any time the actual chemical capacity is higher than the controller thinks it is the controller will prevent the battery from reaching its potential.
Used to have older PSP batteries reach 100% real quick, quick fix was to deep discharge through the controller using a small light bulb. The battery would then take a significant charge and last a few more months before kicking the bucket.
Jspeer said:
I read that a battery will last longer if you don't let it get below 40%, and full discharges are bad for the longevity. Is this true? Here is a good read on the subject. http://batteryuniversity.com/index.php/learn/article/how_to_prolong_lithium_based_batteries
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Click to collapse
40% is a good number for storage, its actually better to store it at 40% than 100%. Actual use 20 to 25% is my personal range but I would say just never let it get below 15%. Lithium Ion does not mind being topped off. Deep discharged will ruin it real quick. My laptop battery lasted 3 years never letting it go below 25%, murdered a cell phone battery once a year letting it die.
I let it go to 1% and turn itself off. Then I charge it back up. But if I know I am going out in the next few hours I charge it as much as I can before I leave.
markdapimp said:
Li-ON battery's do not need to be calibrated. that was only with old battery tech such as Ni-Cad or NIMH
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lots of the fuel gauges for these types of batteries do need to be calibrated. this is not true for the N5 though(i think). I want to say i remember reading that this fuel gauge is different, like a 'smart fuel gauge' or something
kmx said:
I let it go to 1% and turn itself off. Then I charge it back up. But if I know I am going out in the next few hours I charge it as much as I can before I leave.
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You shouldn't do that almost ever. And by no means as a regular practice.
Molitro said:
You shouldn't do that almost ever. And by no means as a regular practice.
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Thats what the built in protection is for:
Marine6680 said:
The effect is accelerated/more pronounced below 20%...
Here is the good thing though... These phone's minimum operating voltage is higher than the minimum voltage of a Li ION battery. Using standard battery life measurements, the 0% according to the phone, is about 20% of standard.
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Enddo said:
lots of the fuel gauges for these types of batteries do need to be calibrated. this is not true for the N5 though(i think). I want to say i remember reading that this fuel gauge is different, like a 'smart fuel gauge' or something
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Its not any different. as with older battery technologies they would loose capacity until they are calibrated 0% to 100% this is due to the chemistry of the battery
LI-ON battery's have a different chemistry which allows them to store greater capacity without loss like NI-CAD and NIMH did this is why you turn off your phone for a week and turn it on you find it still has about the same battery percentage as you turned it off before.
here's an example of a NI-CAD battery which needs to be calibrated.
You have a drill you haven't used for 3 days it was fully charged before you put it away if you take that same drill 3 days later you'd find it dead. where as LI-ON battery's would still be alive and full capacity. if you charge it from there it wouldn't be calibrated. as calibration requires you to drain the battery 2 times or more till it reaches it full capacity and charge it back up to 100% and repeat.
If you were to do that with a LI-ON battery you're basically doing nothing but wasting your charge cycles on the battery and you could kill it as LI-ON battery's DO NOT LIKE TO BE EMPTY
Because of all that NI-CAD and NIMH mess mostly all power tools you'd find in a shop such as home depot are now equipped with LI-ON battery's as they don't require calibration and can be left for months and it would still have its initial capacity prior to charging because Ni-cad battery's suffer from a memory effect and LI-ON does not, NI-CAD Requires full discharge before recharge LI-ON does not you get the point here right? LI-ON is better!
Now for those apps that claim calibrate the battery they do nothing they just Improve the reading of the software in android to get the battery percentage which is reset every time the battery charges to 100% so in short don't calibrate your battery
You can read more here http://www.diffen.com/difference/Li-ion_vs_NiCad
and watch this video: http://www.youtube.com/watch?v=hrcbcm11830
markdapimp said:
Its not any different. as with older battery technologies they would loose capacity until they are calibrated 0% to 100% this is due to the chemistry of the battery
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The battery controller is still the source of the problem. If the batteries chemical capacity at a given moment is 1800 mah down from its original 2300 and the charge controller thinks the capacity is 500 the controller will only charge the battery to 500. Most controllers do not act like their dumber counter parts which will trickle or cut off when the cells characteristics indicate it is reaching a full charge.
The controller in these batteries while varying greatly in design all have one thing in common. They are designed for safety. The controller will actually stop accepting a charge forever if the voltage of the cell goes below a certain point. It will also never charge it above the current observed maximum capacity no matter what reality is.
You can poll a battery using vendor specific commands to get the designed, current maximum and current charge. The current maximum charge capacity is a changing value it will change over the life of the battery. This was an aging laptop battery that while the controller knew what the "Full Charge Capacity" was currently it decided not to report that to windows resulting in a hilarious 410%.
But we are talking about a problem that really won't rear its head for 1 or 2 years and were talking about doing it once or twice over the life of the battery. People doing it now and all the time WILL kill the battery very quickly for no benefit.
markdapimp said:
Its not any different. as with older battery technologies they would loose capacity until they are calibrated 0% to 100% this is due to the chemistry of the battery
LI-ON battery's have a different chemistry which allows them to store greater capacity without loss like NI-CAD and NIMH did this is why you turn off your phone for a week and turn it on you find it still has about the same battery percentage as you turned it off before.
here's an example of a NI-CAD battery which needs to be calibrated.
You have a drill you haven't used for 3 days it was fully charged before you put it away if you take that same drill 3 days later you'd find it dead. where as LI-ON battery's would still be alive and full capacity. if you charge it from there it wouldn't be calibrated. as calibration requires you to drain the battery 2 times or more till it reaches it full capacity and charge it back up to 100% and repeat.
If you were to do that with a LI-ON battery you're basically doing nothing but wasting your charge cycles on the battery and you could kill it as LI-ON battery's DO NOT LIKE TO BE EMPTY
Because of all that NI-CAD and NIMH mess mostly all power tools you'd find in a shop such as home depot are now equipped with LI-ON battery's as they don't require calibration and can be left for months and it would still have its initial capacity prior to charging because Ni-cad battery's suffer from a memory effect and LI-ON does not, NI-CAD Requires full discharge before recharge LI-ON does not you get the point here right? LI-ON is better!
Now for those apps that claim calibrate the battery they do nothing they just Improve the reading of the software in android to get the battery percentage which is reset every time the battery charges to 100% so in short don't calibrate your battery
You can read more here http://www.diffen.com/difference/Li-ion_vs_NiCad
and watch this video: http://www.youtube.com/watch?v=hrcbcm11830
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look man
http://batteryuniversity.com/learn/article/how_to_prolong_lithium_based_batteries
Partial discharge on Li-ion is fine; there is no memory and the battery does not need periodic full discharge cycles to prolong life, other than to calibrate the fuel gauge on a smart battery once in a while.
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now believe what you want
Once in a while isn't explicit. The video posted earlier says once a year or so... both of those are "a while" to me
It all depends on the controller and the software but mostly its no longer necessary.
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Molitro said:
You shouldn't do that almost ever. And by no means as a regular practice.
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Thanks for the recommendation.:angel:
rootSU said:
Thats what the built in protection is for:
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Fair enough.
But still doens't seem like a good practice given how the recommendations with this kind of tecnology are usually don't go too low and try to charge at different values, not always plug the charger at the same level.
Li Ion batteries charge to a maximum voltage before the charge stops in a phone or other device that charges while also operating.
To fully charge a Li Ion battery you need to monitor current draw of the battery as it is charging, it drops as the cell reaches saturation. This is difficult to do in an operating circuit... Though the tech may be getting better, as load sharing was not common for charging cell phones a few years ago, but it may now be, I have actually been looking for info on powered device charging, but find little beyond load sharing type.
So the battery in a phone could hold more juice if it was charged out of the device, and more still if the phones could run at the 3v minimum of Li Ion. (min voltage of arm devices is around 3.5v) Load sharing chargers can charge fully though.
Also charge rate affects battery life... slower charging is better for long lifespan. If you overnight charge, use the lowest rated charger you have, or standard USB charging. The current phones come with higher amp chargers now... It really doesn't speed up the overall charge cycle to 100% very much, but it does make charging to 80% quicker. So you can do a quick charge of a low battery to a usable level in a hurry.
Power tools use LiFe chemistry batteries which are more tolerant of abuse and misuse... at the cost of less voltage and capacity and more weight.
I work from home so it's easy for me to top off the phone as needed. I'll usually throw it on the charger for a while around 3-ish PM to make sure that I have a full charge going into the evening since I do a lot of reading on it after the kids are in bed. I'm definitely what you would call an opportunistic charger - there's no need to drain the battery all the way unless you absolutely can't get to a charger. I don't understand why people choose to run their batteries down all the way when they don't have to.
A Li-ion battery has a limited numer of charge cycles, but what constitutes a charge cycle? According to some people a charge cycle is used every time the charger is connected. Another opinion is that only a charge from 0 - 100% consumes one charge cycle. So how is it really? If the first assumption is true then one should only charge when the battery is almost emty. If the other one is true then it's ok to charge at any time.
Tom200 said:
A Li-ion battery has a limited numer of charge cycles, but what constitutes a charge cycle? According to some people a charge cycle is used every time the charger is connected. Another opinion is that only a charge from 0 - 100% consumes one charge cycle. So how is it really? If the first assumption is true then one should only charge when the battery is almost emty. If the other one is true then it's ok to charge at any time.
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A charge cycle is the process of charging a rechargeable battery and discharging it as required into a load. The term is typically used to specify a battery's expected life, as the number of charge cycles affects life more than the mere passage of time. Discharging the battery fully before recharging may be called "deep discharge"; partially discharging then recharging may be called "shallow discharge.
Apple Inc. clarifies that a charge cycle means using all the battery's capacity, but not necessarily by full charge and discharge; e.g., using half the charge of a fully charged battery, charging it, and then using the same amount of charge again count as a single charge cycle. -Wikipedia
Hit thanks if I helped
Rumple007 said:
A charge cycle is the process of charging a rechargeable battery and discharging it as required into a load. The term is typically used to specify a battery's expected life, as the number of charge cycles affects life more than the mere passage of time. Discharging the battery fully before recharging may be called "deep discharge"; partially discharging then recharging may be called "shallow discharge.
Apple Inc. clarifies that a charge cycle means using all the battery's capacity, but not necessarily by full charge and discharge; e.g., using half the charge of a fully charged battery, charging it, and then using the same amount of charge again count as a single charge cycle. -Wikipedia
Hit thanks if I helped
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Ok, but that means that charging the battery a lot instead of waiting until it's almost completely drained, shortens its lifespan.
Ideally, a Lithium based battery is "healthiest" at or about mid level. A full charge cycle is technically not 0-100%, as these batteries (at least in consumer electronics) have circuitry built-in to prevent overcharging, overdischarging, and shorts. Overdischarging can cause what's called runaway discharge, where it'll keep discharging even if not connected to anything or the device is turned off. Heat, possible fire, and even explosion. Those Dell and Sony laptops that were catching fire several years ago? That was because the protection circuitry was faulty. And why you should always buy OEM factory batteries, or ones made by reputable companies like Zerolemon or Anker, and not cheap Chinese knockoffs. Hobbiests (flashlights, R/C equipment) often use unprotected batteries since they can get a bit more capacity out of them, but this is dangerous and requires monitoring and judgement.
So the answer is a charge cycle is from 0-100% and back down to 0% (or the opposite; charged, discharged, then charged - depending on your point of view), where 0% is the point where the circuitry within the battery and/or the device itself cuts the power.
There is no need to "condition" lithium rechargeable batteries (ie: fully drain them, don't use until fully charged, etc); this is a holdover from the days of nickel-cadmium (Ni-Cad) batteries, which did require conditioning for optimal performance.
The main destroyer of a lithium battery really isn't even the charge/discharging of it, but rather the heat associated with it. For example, one can keep a battery charging and charged at 95-100% while playing an intense game, downloading a large file, or running a wi-fi hotspot, but this sill quickly destroy the battery, even there's no actual "cycle" happening. The ~500 charge cycle figure assumes a typical usage of training and charging. The reason a battery is "healthiest" at mid levels is that this is where there's the least heat being generated.
Yeah, I have kind of adapted to the thought that charging whenever doesn't impact the battery in a negative way. So if my charge is 80% and I'm going out for the day, I still charge it to full 100%. If however (as the first answer suggests) this consumes an extra cycle then it would be best not to charge it. In the past this didn't matter so much but with many phones these days it's hard or even impossible for the user to replace the battery. This makes the answer to my question more important...
Tom200 said:
Yeah, I have kind of adapted to the thought that charging whenever doesn't impact the battery in a negative way. So if my charge is 80% and I'm going out for the day, I still charge it to full 100%. If however (as the first answer suggests) this consumes an extra cycle then it would be best not to charge it. In the past this didn't matter so much but with many phones these days it's hard or even impossible for the user to replace the battery. This makes the answer to my question more important...
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80-100% is not a cycle, it's 20% of a cycle. However, it is the worst part of the cycle (higher voltages, more heat). Ideally, for the battery's health and longevity over the months/years, it'd be best to keep it between, say, 30-70%. But this is impractical, potentially impossible for some, and, frankly, dangerous.
That's why I'll only buy phones with replaceable batteries. Either instantly, or without terrible difficulty when the battery hits that ~500 cycle mark. I have 3 phones: A Galaxy S4 (with a couple spares, including a 7800mAh Anker), a Nexus 4, which I've replaced the battery on, and a OnePlus One, which I know I can replace if/when I need to. I'll never get something like a S6 or Note5 or iPhone where battery replacement is nigh-impossible.
Planterz said:
80-100% is not a cycle, it's 20% of a cycle. However, it is the worst part of the cycle (higher voltages, more heat). Ideally, for the battery's health and longevity over the months/years, it'd be best to keep it between, say, 30-70%. But this is impractical, potentially impossible for some, and, frankly, dangerous.
That's why I'll only buy phones with replaceable batteries. Either instantly, or without terrible difficulty when the battery hits that ~500 cycle mark. I have 3 phones: A Galaxy S4 (with a couple spares, including a 7800mAh Anker), a Nexus 4, which I've replaced the battery on, and a OnePlus One, which I know I can replace if/when I need to. I'll never get something like a S6 or Note5 or iPhone where battery replacement is nigh-impossible.
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Yeah, it's very annoying that not batteries on all cell phones are user replaceable. And we can exchange them on some phones anyway with a little trouble, but as you write it's completely impossible with some. I put in the charge if my battery is 50% or something and I'm going out later. This should consume only half a a cycle and it's practical for me.
I now charge when the battery is like 75% before I'm going out. Is this ok or should I let the battery drain and then charge? The latter I did for a long time with a phone I had, and the battery had great performance until I sold it.