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Recently many users of the Motorola Defy phone have encountered sudden drops in battery charge after installing a new ROM. Such as, drops from 67% to 49%, from 34% to 19%, from 7% to 4%, etc.
I also have encountered such problem when installed CM7.2 after being used stock Froyo ROM for more than an year. I had searched forums for possible fix, but no method has helped.
Finally, I have made some tests with my phone and found interesting points about Defy battery that explain battery percentage drops.
Our Defy have very simple battery controller (it is referred as cpcap by Motorola). The controller does not calculate and provide battery percentage. It provides only a battery voltage and a current. The battd daemon do the battery percentage estimation. It seems some overcomplicated estimation algorithm is used to do that (I've seen the Coulomb counter technique is mentioned in the battd sources).
There are several battery percentage checkpoints at 5%, 20%, 50%, 80%, 100%. It seems the battd daemon have a voltage-percentage mapping table for these checkpoints. When a battery voltage reaches a checkpoint value then the percentage is immediately set to a corresponding value. All other intermediate percentage values are estimated by the battd daemon. The estimation is based on a battery capacity (requested from the battery itself) and the active current. A stock battery reports 1500 capacity. A 1700mAh Chinese battery, I also have, reports only 1200 capacity :laugh: battd stores the last calculated battery percentage and voltage in the /data/battd/cc_data file. Data from the /data/battd/cc_data file is read on start-up and the percentage from this file is used as base and reported to the system. When battery is drained, the percentage is decremented. When you delete the cc_data and reboot, battd uses the current voltage and looks for the nearest checkpoint voltage value and sets the percentage accordingly.
How have I found the checkpoint values above?
Assume we have a brand new original Defy battery and it shows 25% of charge.
If you delete the cc_data file and then reboot the phone, battd will recreate the file and request the battery controller(?) for the current battery status. The controller will return 50% and battd show 49% to you (not 49% not 50%, due to rounding to the lowest integer). But the real charge is 25%! Now let the battery discharge. It will show to you 48%, 47%, 46%, etc. Great! But at 40-44% you get the instant drop to 19%, since the battery controller had reported real 20% charge at that point and battd has been forced to sync its estimated charge value to the real charge value.
When a battery is wearing its actual capacity is decreased. For example, it may be 1300 mAh after an year of usage. But battery still reports it have 1500 capacity and battd uses this capacity for its calculations. battd should decrement percentage a bit faster for this worn battery, but it still use the same decrement speed as for a new 1500 battery. When battery voltage reaches a check point value, battd updates percentage to corresponding checkpoint value and you register a drop.
battd has some battery information and correction data in the /pds/public/battd folder. This data helps battd to estimate battery charge more correctly. This folder contain 3 files:
Code:
batt_offset_data
batt_phasing_data
batt_tuning_data
Without this correction data you may encounter slight drops even on a new stock battery,
For Defy there at least 2 versions of battd. (Defy+ uses a different battd) Let's name them as old and new ones. To find out which version you have, check the size of the /data/battd/cc_data file.
cc_data = 16 bytes - old battd,
cc_data = 24 bytes - new battd.
Early stock Froyo ROMs have the old battd, newer stock ROMs have the new battd. CM7.2 is bundled with the new battd.
Is the battd version makes any difference in the battery readings? YES. The difference is in a user account which is used to run a battd daemon.
The old battd uses the mot_accy user account, The new battd uses the system account. The corresponding owner and group should be set for the /pds/public/battd folder and files inside it. Otherwise battd will not be able to read battery data from the /pds/public/battd folder and defaults will be used, which cause inaccurate estimations.
If you have used stock old Froyo ROM or old custom ROM, you had the old battd. The /pds/public/battd folder has permissions for the mot_accy user account only.
You install the CM7.2 ROM with the new battd and it can not read battery data from the /pds/public/battd folder, since battd is run under the system user account. You have inaccurate battery estimation and percentage drops even on a brand new battery.
That's why installing the old battd (and its companion lib libbattd.so) on CM7.2 resolves battery drops issue for some users.
If you are using CM7.2 or any newer CM you can just change the owner and group for the /pds/public/battd folder and files inside it. Set both owner and group to system and the new battd will be able to read battery data files.
If you still have battery drops then your battery is worn to some degree and battd can not estimate its charge properly between checkpoints.
Is it possible to correct this? Probably yes.
I was able to adjust checkpoint voltage values and eliminate drops on checkpoints. BUT the discharging speed is still the same and I have good discharge without drops from 100% to 10% and phone is turned off on 10% since a battery reaches critical voltage of 3.050V.
To adjust checkpoints it is needed to change the /pds/public/battd/batt_offset_data file. I have changed the last 3 bytes to 0xA0. It offsets voltage value for checkpoints on 50%, 20% and 5%.
The batt_phasing_data file have not helped at all in my tests. It contains correction values for displayed voltage, temperature, current.
The batt_tuning_data file is total mystery atm.
So the goal is to find a way to force battd to decrement percents faster for worn batteries. The simplest way is to patch the battd with hardcoded capacity value (e.g. 1300) instead of reading this value from the battery.
The other (better) option is to create a custom battery driver and use a very simple mapping from current voltage to percentage. Such method is used to display battery status in touch boot menu. Also Quarx started a custom battery driver some time ago in his git repository.
Important:
The battery calibration is a myth! The /data/system/batterystats.bin file is not related to battery charge/life/status (exactly as Google devs stated earlier).
In case of our Defy, charge the battery to 100% and keep charging for few hours after that. Then disconnect it battd will display correct 99%. That's all you need when changing ROMs or batteries! Do not waste your time on "battery calibration"!
Conclusion:
Find out which version of battd you are using.
Check owner and permissions for the /pds/public/battd folder and files inside it. Correct owner/permissions if needed.
Charge your battery to 100% and keep charging for few hours more.
If you still have battery percentage drops after that, your battery is worn to some degree. The sum of dropped percents indicates how bad is your battery (-10%, -15% etc, compared to a new battery). There is no way to magically increase real life for this battery. Drops just a display issue due to crappy cheap battery controller in our Defy and weak battd estimation logic. That's why stock ROMs have 10% steps for battery charge - to hide such issues.
nice investigation, indeed great job.
however, i would not agree to this:
jusid said:
Conclusion:
If you have battery percentage drops after single full battery charge, your battery is worn. The sum of dropped percents indicates how bad is your battery.
Click to expand...
Click to collapse
there's also hoop while charging which "compensates" the drop. moreover, there are no sudden voltage drops or so which would mean the battery is just fine, only the readings fail.
i wonder if can it be fixed or so by our devs?
MarcinRN said:
there's also hoop while charging which "compensates" the drop. moreover, there are no sudden voltage drops or so which would mean the battery is just fine, only the readings fail.
i wonder if can it be fixed or so by our devs?
Click to expand...
Click to collapse
Slightly worn battery does not have voltage drops, it just discharges faster due to lower capacity. battd expects slower discharging speed (as in a new battery) while making calculations. That's why the drops occurs when the real charge got from the controller. Drops are just a display issue, but your battery is worn to some degree (-10%, -15%, etc)
This thread should be stickied, or the info added to the all in one defy beginner guide
jusid said:
Slightly worn battery does not have voltage drops, it just discharges faster due to lower capacity. battd expects slower discharging speed (as in a new battery) while making calculations. That's why the drops occurs when the real charge got from the controller. Drops are just a display issue, but your battery is worn to some degree (-10%, -15%, etc)
Click to expand...
Click to collapse
Thanks I get it now. But the question is can anything be done to make it more accurate?
Great round up!
Would you mind supporting your findings with sources? Helps against criticism, trolling and so on...
Thanks a lot for sharing.
MarcinRN said:
Thanks I get it now. But the question is can anything be done to make it more accurate?
Click to expand...
Click to collapse
As I mentioned before, possibly battd has some auto-adjusting logic, bat I'm not sure about that. The solution is to create some proxy between battd and the system with a better estimation logic or create a new battd. But both are quite hard to implement.
As for me, I am going to purchase a new non-stock battery. Then I test how its controller behaves.
measel said:
Great round up!
Would you mind supporting your findings with sources? Helps against criticism, trolling and so on...
Thanks a lot for sharing.
Click to expand...
Click to collapse
These findings are based on simple tests. One of them is described in the OP.
For example, discharge your battery to 51%, then delete files in the /data/battd folder. Reboot the phone. You will get 79% of charge, since the controller reports 80% and the nearest lower step is 50% and it is not reached yet. Then the phone will show 78%, 77%, etc for some short time and then suddenly drops to 49% when the battery controller report the real charge to the system.
Using such method I have found all possible values which are reported by the controller of the stock Defy battery - 0%, 5%, 20%, 50%, 80%, 100%...
Excelent work... I've notice that it was a system behavior instead of a bug, but the test you've made everything very clear.
I'm waiting to buy a new battery on a official reseller, the one I've bought is not genuine and showed the same behavior.
Sadly, I replaced my battery with a new one, the drop still show up, this disprove some of your points. But still thanks for the useful information.
for me is working this fix made by me for my DEFY+ bl7 (files from stock ROM)
Sent from my MB526 using xda app-developers app
If you have DEFY+ try this http://forum.xda-developers.com/showpost.php?p=28893630&postcount=150 and you will see
Sent from my MB526 using xda app-developers app
Sent from my MB526 using xda app-developers app
it's there a difference between ur stock battd file from bl7 ROM and the other battd files? maybe it's better programmed from moto ^^
Defy mit Android 4.0.4 CM9 RockZ
Chelsea888 said:
Sadly, I replaced my battery with a new one, the drop still show up, this disprove some of your points. But still thanks for the useful information.
Click to expand...
Click to collapse
There are several battd versions are floating around. Maybe some of them is better for your battery.
Also if you have purchased a stock moto battery on ebay, it may be not new, but already used...
I have found that battd has references to the following files in the /pds/public/battd folder:
batt_phasing_data
batt_tuning_data
batt_offset_data
Probably they contain some tuning parameters to prevent drops for worn batteries...
Something is missing here... because when I flash cm9 for the first time in my 1 month defy, suffer the battery drops in a really weird way (67 to 30, 30-19, 19-4) in just 10 mins. So, this happen even in a new battery.
Enviado desde mi MB525 usando Tapatalk 2
this indeed is a very helpful insight into the how and why of charge drop on our defy...i had observed this shoot ups on reboot and drops imminently afterwards also but couldn't pin onto it due to my lack of expertise...you made it all so clear...a big thanks...and certainly Moto is a bad implementer of good hardware as has been evident with their Defy with robust cpu/gpu...camera hardware...etc...maybe that is also a reason why they do not provide support for their older models for software upgrades as well
espaciosalter20 said:
Something is missing here... because when I flash cm9 for the first time in my 1 month defy, suffer the battery drops in a really weird way (67 to 30, 30-19, 19-4) in just 10 mins. So, this happen even in a new battery.
Enviado desde mi MB525 usando Tapatalk 2
Click to expand...
Click to collapse
You need to charge the battery to 100% just after installing a new ROM. After that the battd will be synced with the real battery charge. After that if the battery is OK there should be no drops.
But battd auto-adjustments and different battd versions need to be investigated...
As walter79 once said, after the total battery charge, keep the phone to charge more for an hour!
For me it worked on any rom I tested!
jusid said:
Conclusion:
If you have battery percentage drops after single full battery charge, your battery is worn to some degree. The sum of dropped percents indicates how bad is your battery (-10%, -15% etc, compared to a new battery). There is no way to magically increase life for this battery. Drops just a display issue due to crappy cheap controller in Defy batteries and weak battd estimation logic. That's why stock ROMs have 10% steps for battery charge - to hide such issues.
And finally:
The battery calibration is a myth! The /data/system/batterystats.bin file is not related to battery charge/life/status (exactly as Google devs stated earlier).
In case of our Defy, real battery status is synced with the battd status when you charge to 100%. That's all you need when changing ROMs or batteries!
Click to expand...
Click to collapse
I'm glad someone addressed this problem, but when I first flashed CM7.1.0 waaay back a month after I got my phone, it had this problem. Battery worn? I don't think so.
Anyways, this discussion seems to make sense, but it would really be nice if you could cite some sources. Thanks again.
Hi everybody!
i've got a little doubt about the battery calibration method and tool..so...i've done all the process(the one suggested by the user Ganymedes with the battery calibrator from the market) every time i flashed a new rom update(in this case the sandvold ICS),for calibrate the original 1400mAh desire battery,and also because my desire shutted down at around 15% battery remaining..and every time without any positive result..so i tried in many ways,and at the end i kept the battery as it comes out after all the times i tried to calibrate it...but now,i just bought a brand new high capacity mugen battery..the bigger one with 3200mAh,'cause the old one drained too fast..so,the question is..i've got to recalibrate the phone again,'cause i changed the battery?..i wish to precise that i haven't calibrated the battery after the last ROM update..so,what you think?'cause i read that the battery calibrator app will save and make permanent the battery stats..and i'm afraid that an old batterystats with the info from the stock battery is still saved..misreading the power of the new battery!
thanks for all the answers!
Is far as I know the calibration configuration is saved on the battery not on the rom.
stankyou said:
Is far as I know the calibration configuration is saved on the battery not on the rom.
Click to expand...
Click to collapse
So i don't need to re-calibrate the device for the new high capacity battery..isnt'it?
Cesk87 said:
So i don't need to re-calibrate the device for the new high capacity battery..isnt'it?
Click to expand...
Click to collapse
So you need to calibrate it because you replaced the battery.
via xda app
Cycling the battery through one full charge and full dis-charge cycle should do the trick. I don't think a calibration tool will help much. Wiping battery stats is also useless.
I just acquired a Xperia S one week ago, and then i realized that battery is very poor. with full charging it got three hours of use to hit 15%, during these three hours the phone was in flying/airplane mode. The first two hours i used memedroid with wi-fi and opera mobile navigation and downloads, the last hour i played temple run 2. Its normal such battery life? before this phone i had a lg p990 which i considered very very poor the battery life, but the xperia s just broke the record. sorry for bad english, i'm brazilian '-'
my average battery usage is about 9 hours, usually unplug from charger about around 7am, around 4pm battery empty.
Androids aren't popular for battery life. But it can be increased by doing several customizations since Androids are meant for customizations.
So before complaining please check the battery life related threads in General sections. You'd find many tweaks and tips from other users.
Hello Jr, i´m BR too. Write in english ...bad english....rs
My battery life in LT26i is 12h with all things "on": BT, GPS, 3G and WIFI. I install PAC ROM V19 , but when i have Stock ROM my battery life is the same with updated system. Maybe your phone have any problem and you can change if have NF and between 7 days of purchase. You see the "battery stats" in "Setting" to see how apks drain battery ?
Hello m8 .
There are several ways to check if your battery is OK (but I think it should be, as Android device with HD screen just eat battery)
First of all, we can check if you battery health is good. To do that, in phone dialer enter this code: *#*#7378423#*#* (it's same as: *#*#SERVICE#*#*). There enter to "Service tests" > Battery Health Test. In my phone it looks like in photo in attachment. Don't worry if value in "Actual Batt(uAh)" is lower than 1750mAh. When you use your phone correctly, I can be around 1650~, too, but after fully charging this "counter" sometimes reset. More important thing is information, that health is good, and battery is no need to be replaced.
If this part is correct, now enter Settings > Battery. Here you can find information what consume your battery in pertencage of currently "eaten" % battery (example: You have 80% battery remaining, so you've lost 20%. There's information, that "Screen" or anything else eat 60% of battery. It means, that in these 20% of current lost battery -> It has been lost for screen).
Most discharging things in our phone are:
Screen - try to turn off Mobile Bravia Engine if not used (not watching movies), and decrease brightness.
WiFi & Data Transfer - If not used, turn off your WiFi.
Hope this helps
Also remember that the first charges are smaller.
Hopefully I'm helping an not hindering...so here we go.
I ran AnTuTu tester on my Sony XPERIA S 1750mAh battery which is reported to be in good health.
Now I'm not sure how much faith I place in this application as it didn't list my CPU usage, where on my XPERIA X10i it did.
My XPERIA S is rooted and using RaymanFX' ELiTE kernel with GPU and CPU over-clocked.
I started the test with my battery fully charged.
I got a battery life from 100% to 19% of 1hr and 50min using a 1750mAh battery on a dual-core CPU clocked at 1566MHz.
Yes, I know, that scared me too.
The same test on my Sony Ericsson XPERIA X10i returned the following.
I got a battery life from 100% to 19% of 3hr and 17min using a 1800mAh battery on a single-core CPU clocked at 1113MHz.
Now this may not be as bad as things look as we have two CPUs ripping into a battery compared to 1 CPU so there may be pause for reflect and thought on this battery usage in this case.
So, long story short, if you run the same test at 1.5GHz (stock ROM) and you get a battery life of approx 1hr and 50mins (or more) using the AnTuTu Tester your battery should be able to give you a days usage in moderation.
This is not exactly science, but it may give some indication if your XPERIA S(LT26i) 1750mAh battery is operating in a 'normal' threshold.
Odp: [Q] Xperia S battery life very poor, its normal?
So that's why I bought external battery for phones from Sony, CP-EL. 2000mAh.
Tap Tap Tapatalk - Sony Xperia S
ThaweK said:
So that's why I bought external battery for phones from Sony, CP-EL. 2000mAh.
Tap Tap Tapatalk - Sony Xperia S
Click to expand...
Click to collapse
but this 2000mAh has a higher size compared to the stock 1750 battery, anyway, it works fine?
ThaweK said:
Hello m8 .
There are several ways to check if your battery is OK (but I think it should be, as Android device with HD screen just eat battery)
First of all, we can check if you battery health is good. To do that, in phone dialer enter this code: *#*#7378423#*#* (it's same as: *#*#SERVICE#*#*). There enter to "Service tests" > Battery Health Test. In my phone it looks like in photo in attachment. Don't worry if value in "Actual Batt(uAh)" is lower than 1750mAh. When you use your phone correctly, I can be around 1650~, too, but after fully charging this "counter" sometimes reset. More important thing is information, that health is good, and battery is no need to be replaced.
If this part is correct, now enter Settings > Battery. Here you can find information what consume your battery in pertencage of currently "eaten" % battery (example: You have 80% battery remaining, so you've lost 20%. There's information, that "Screen" or anything else eat 60% of battery. It means, that in these 20% of current lost battery -> It has been lost for screen).
Most discharging things in our phone are:
Screen - try to turn off Mobile Bravia Engine if not used (not watching movies), and decrease brightness.
WiFi & Data Transfer - If not used, turn off your WiFi.
Hope this helps
Click to expand...
Click to collapse
Since i bought my phone the mobile bravia engine is turned on.... i did the test and the battery health is good, i will try to close apps and decrease the brightness, and see if a get a decent battery life. I use only wifi, no data transfer, and 2G connection. If i cant get success i will wait for sony's JB update.
The guy who posted the benchmark up there should be reminded that you're using a dual core in Xperia S plus each core is built on 45nm technology which means that the newer snapdragon phones are likely to be more battery conservative than the one used in xperia s because it produced around double the heat...
I changed my omnia II ([email protected]) to xperia s and I was shocked with its battery. now I got used to charging it twice a day with really heavy use or once for two days with normal use.
> Go for a ROM with minimum size and least applications. This lighter ROM saves battery by eliminating the junk running in the stock's background. Less CPU usage = Less battery drain
> Reduce the brightness to save power since the 4.3" 720p is a battery hog.
> You can also try switching on 3G and Wireless only when required.
But don't be worried (if you were), almost all androids suck at battery timing.
I relocked my bootloader and installed the original firmware and now android system is using up 66%.. though it still lasts 14 to 15 hours with average use, it can be much more, but i've no idea what the problem is.
BBS says "AlarmManager", but since I don't have root anymore I can't figure out which process/app is getting all these partial wakelocks :crying:
GabrielBezerra said:
but this 2000mAh has a higher size compared to the stock 1750 battery, anyway, it works fine?
Click to expand...
Click to collapse
It's an external battery. Imagine it as you were charging your phone out of your notebook's battery. It is way bigger, so it uses just a part of it.
Sent from my LT26i using Tapatalk HD
Odp: [Q] Xperia S battery life very poor, its normal?
Felimenta97 said:
It's an external battery. Imagine it as you were charging your phone out of your notebook's battery. It is way bigger, so it uses just a part of it.
Sent from my LT26i using Tapatalk HD
Click to expand...
Click to collapse
Yup. However, if you're using your phone normally during charging it will use full 2000mAh and there still won't be full but ex. You can watch about two full movies more for ex. during trip
Tap Tap Tapatalk - Sony Xperia S
Hello
A few weeks ago i installed clockworkmod en cyanogenmod 9. This because i thougth it would be better for my battery.
When i installed those mods, i didn't remove the batterystats.
By installing those mods, i concluded that the software wasn't the problem why my battery was draining that much, but it was the battery itself.
When i brought it back to the store, they told me it was damaged.
So because of that, i ordered a new one.
Now i have the following question.
1) When i replace my old battery with the new, do i have to clear the batterystats via clockworkmod?
2) in fact, i never cleared those stats. Should i have to do this?
Thanks!
Ps, sorry for my bad english.
Midfieldgeneral said:
Hello
A few weeks ago i installed clockworkmod en cyanogenmod 9. This because i thougth it would be better for my battery.
When i installed those mods, i didn't remove the batterystats.
By installing those mods, i concluded that the software wasn't the problem why my battery was draining that much, but it was the battery itself.
When i brought it back to the store, they told me it was damaged.
So because of that, i ordered a new one.
Now i have the following question.
1) When i replace my old battery with the new, do i have to clear the batterystats via clockworkmod?
2) in fact, i never cleared those stats. Should i have to do this?
Thanks!
Ps, sorry for my bad english.
Click to expand...
Click to collapse
Battery stats are cleared whenever your battery reaches 100% (when you fully charge it). So it actually is useless to manually reset the battery stats.
Ok so your battery is damaged? How was the battery life before you flashed CM9? I don't think that it is the ROM's fault. Was your battery swollen? (getting fat)
No you dont have to reset battery stats.. Just keep in mind that CM9 and CM10 uses kernel 3.0 and they cause fast battery drain...You may have to install some apps to prolong the battery life like deep sleep battery saver and Greenify.
thearif said:
Battery stats are cleared whenever your battery reaches 100% (when you fully charge it). So it actually is useless to manually reset the battery stats.
Ok so your battery is damaged? How was the battery life before you flashed CM9? I don't think that it is the ROM's fault. Was your battery swollen? (getting fat)
No you dont have to reset battery stats.. Just keep in mind that CM9 and CM10 uses kernel 3.0 and they cause fast battery drain...You may have to install some apps to prolong the battery life like deep sleep battery saver and Greenify.
Click to expand...
Click to collapse
Hello,
Battery life before CM9 wasn't also that good.
This was one of the reasons why i changed to CM9.
After the installation, i noticed that there wasn't improvement in batterylife. It become even a bit worser...
Because of this, i went to the store to check the battery. They tested it and told me that the battery indeed was swollen.
So, if i understand good, i just have to replace the battery without clearing stats.
For the rest i just have to install some apps to counter the kernel 3.0 drainage?
Yeah you are right. Just charge the battery 100% and start using your phone.
Sent from my GT-I8150 using xda app-developers app
http://imgur.com/QMB1kaF
Any solutions to this? I'm trying to use a battery calibration application, but it doesn't seem to be helping all too much.
First thing: The rom you're using, battery drain is popular problem on ics.
Second: Setting CPU and screen light to lower values, Turn Wifi on only in need, background data use is also non-friendly to battery
Third: you can buy bigger battery, our Gio's one is not that good
Fourth: You can install some tweaks from xda(like crossbreeder or fly on mod) but don't expect miracles.
A6ekAK said:
First thing: The rom you're using, battery drain is popular problem on ics.
Second: Setting CPU and screen light to lower values, Turn Wifi on only in need, background data use is also non-friendly to battery
Third: you can buy bigger battery, our Gio's one is not that good
Fourth: You can install some tweaks from xda(like crossbreeder or fly on mod) but don't expect miracles.
Click to expand...
Click to collapse
No, it's not the battery drain, it's the battery calibration.
I can look at the phone while its charging and see the battery percentage go from 72% to 78%. And no, I dont mean 72,73,74,75,76,77,78, I mean 72 straight to 78. Also, battery percentages also drop from 100-80 in the first few minutes then 80-70 take eternity. The calibration is awful.
Think of what you're talking :d
That "drops" are perfectly normal, nothing wrong with them. Try CyanogenMod7 roms, in these battery drops very fast from 100 to 20 and then holds long time till 0, "battery calibration" is not magic tool - it just lets you to charge the battery to "real" 100%. If used properly of course - it can also make your battery to last less...
A6ekAK said:
Think of what you're talking :d
That "drops" are perfectly normal, nothing wrong with them. Try CyanogenMod7 roms, in these battery drops very fast from 100 to 20 and then holds long time till 0, "battery calibration" is not magic tool - it just lets you to charge the battery to "real" 100%. If used properly of course - it can also make your battery to last less...
Click to expand...
Click to collapse
It doesnt seem perfectly normal to me. I've never ever seen a device do that ever...