Database Users

Prolonged Battery Charging ~ Yes, I believe it is Safe

Prior to getting the Galaxy S, after I read what Samsung were saying in the manual of not to overcharge, I investigated the reasons and wrote in various topics on the battery and the differences between Li-Ion & Li-Pol battery types.
At that point with all the evidence found it made sense to believe that what Samsung were saying in not to overcharge was accurate.
Basically, at that time it was believed the phone used a Li-Pol, Li-Pol batteries are different in that they are 'wet cell' as opposed to Li-Ion which are 'dry cell' charged.
Li-Pol can be manufactured much thinner but can not be manufactured in different shapes.
This is to allow the wet cells whilst under charge which become hot to move around the battery freely. If a Li-Pol was manufactured in different shapes like Li-Ion it would create a 'hot-spot' in an area where the wet cell could not move fluidly around the remainder of the battery.
However, it has now come to light that this is not the case and that the batteries provided with the phone are indeed Li-Ion.
Anyway, moving on to the present.......
After now getting the phone and doing a bit of testing I have found the overcharging issue NOT to be an issue.
When you commence a charge on the phone the icon changes to a charge state.
However, once the battery has reached maximum charge capacity the battery icon automatically changes to a 'Non-Charge' state and then the phone simply runs off it's own battery. This is despite the phone is still connected to the charger.... It's just that the charger although still attached is no longer charging the battery.
As soon as the battery falls below a certain figure (I've had different figures ranging from 98% right down to 91% which is probably due to whatever the phone is doing at that particular time to wake the phone up from realizing "hey, you are still attached to a charger, now wake up and start charging again").
So to all of us who have been worried about overcharging, my personal advise is to NOT worry and charge as and when you feel the need.
Hope this helps.
Beards

Thanks for clear up, I was always been scared while charging that it may blow up.

Nice find!

However, it has now come to light that this is not the case and that the batteries provided with the phone are indeed Li-Ion.
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When you say "it has come to light", what do you mean? Is it just your deduction from your battery tests, or did you see this info from Samsung?
From what I understood, the LI-Pol overcharging is an issue in theory, but in real life applications its not a problem as long as you use the charger that is designed with LiPol in mind, it will auto shutoff charging once it senses the battery is full.

I have just charged mine from bone empty to full. A notification came up stating that the battery was full and to disconnect the charger. Although the battery monitor app says it is not charging and the normal battery meter has gone solid.
I agree that it seems to stop the charging circuit. Although I thought we were getting LiPo not li ion for these as well it's definitely li ion though.

Morbo66 said:
When you say "it has come to light", what do you mean? Is it just your deduction from your battery tests, or did you see this info from Samsung?
From what I understood, the LI-Pol overcharging is an issue in theory, but in real life applications its not a problem as long as you use the charger that is designed with LiPol in mind, it will auto shutoff charging once it senses the battery is full.
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Click to collapse
Take the battery out and turn it over. Now read the battery type and you will see it says Li-Ion.

if such, it will reduce the re-charge cycle....
i suggest, power off the phone and then keep charge overnight will be safe....
otherwise, if it is on and charges only full then disconnect it

hkfriends said:
if such, it will reduce the re-charge cycle....
i suggest, power off the phone and then keep charge overnight will be safe....
otherwise, if it is on and charges only full then disconnect it
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Click to collapse
Modern battery's don't have cycles where you loose power by continuously topping up the battery.
The practice I use is I charge whenever I get the chance, then after around 30 charges I run it right down and do a full charge.
As to powering off the phone to charge, this is not always convenient.
I need my phone on all the time in case I get an emergency call-out and I'm sure there are others who need their phones on overnight to use as a morning alarm.
Finally, I'm not sure if the practice you mention in powering off the phone and charging overnight would have the same effect in being able to re-charge when the battery level drops.
I think doing it in your method the charger would continuously hit the battery regardless as to whether or not it is fully charged ~ which in effect is what Samsung are saying in not to overcharge.

Beards said:
...once the battery has reached maximum charge capacity the battery icon automatically changes to a 'Non-Charge' state and then the phone simply runs off it's own battery. This is despite the phone is still connected to the charger.... It's just that the charger although still attached is no longer charging the battery.
As soon as the battery falls below a certain figure (I've had different figures ranging from 98% right down to 91% which is probably due to whatever the phone is doing at that particular time to wake the phone up from realizing "hey, you are still attached to a charger, now wake up and start charging again").
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Click to collapse
To me it seems like the phone will NOT use the battery as long as it is plugged in. On my phone the battery meter never drops under 100 % when connected.

Beards said:
Modern battery's don't have cycles where you loose power by continuously topping up the battery.
The practice I use is I charge whenever I get the chance, then after around 30 charges I run it right down and do a full charge.
As to powering off the phone to charge, this is not always convenient.
I need my phone on all the time in case I get an emergency call-out and I'm sure there are others who need their phones on overnight to use as a morning alarm.
Finally, I'm not sure if the practice you mention in powering off the phone and charging overnight would have the same effect in being able to re-charge when the battery level drops.
I think doing it in your method the charger would continuously hit the battery regardless as to whether or not it is fully charged ~ which in effect is what Samsung are saying in not to overcharge.
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Click to collapse
AFAIK, the reason to fully deplete the battery is to properly calibrate the % remaining in your battery. Running your battery down to empty causes more stress to the phone than running it down 50%. I happened to get a free battery with my device, but I would've bought a spare if I didn't get a free one, so I can easily go 3-5 days depending on usage, during this time I have my house and work to do charges. However, let's say I were to be expecting to have less frequent charges, such as taking a vacation, prior to that I would be fully depleting the battery to 0% to calibrate because then the battery level is more important to me. The trade off of long-term life vs short term accuracy is a very easy decision for me to make due to my situation.
In older batteries you had to "use the cells or lose them" situation where it was better, to at least occasionally, completely run down the device rather than doing partial cycles. These days, charging @ 50% 2 times is equivalent to 1 cycle of 100% with less long-term "stress" to the battery.
borchgrevink said:
To me it seems like the phone will NOT use the battery as long as it is plugged in. On my phone the battery meter never drops under 100 % when connected.
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Same for me.

The reason it tells you to unplug the charger when done charging has nothing to do with battery. It is to save power. Battery chargers still draw some power just because they are plugged in. And in these green times it is ofcourse very popular to have warnings everywhere so you can claim to a green company. And every lithium ion and polymer battery contains electronics designed to protect them from abuse. Including over charging. So that will never be a problem on any phone unless you have a defective battery.

Is there a way to disable the message telling you to unplug the charger? I charge my phone overnight and use it as a clock, but when I wake up in the morning and try to see the time there's this huge popup in the middle of the screen telling me my battery has charged.

Joans said:
Is there a way to disable the message telling you to unplug the charger? I charge my phone overnight and use it as a clock, but when I wake up in the morning and try to see the time there's this huge popup in the middle of the screen telling me my battery has charged.
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I think I read that the newest, or maybe just a random middle since something has superseded it, firmware fixed this.

interesting topic thx Beards for sharing your insights.

Overcharging - read the manual
Guys, if you will read the manual that came with your SGS, it says there that "DO NOT OVERCHARGE YOUR BATTERY FOR MORE THAN TWO WEEKS". It obviously means that the battery can be overcharged for more than a day as long as it is not more than 2 weeks ( I doubt if someone will be able to do that). So that confirms also that we can recharge anytime and not necessarily have it done to zero before charging. Hope this helps also

i've pretty much quit worrying about the overcharge after the first month of usage
i was following the auto pop up message, just because i wanted to conserve battery
but having 3 spare battery made me though it's futile
and it was extreme annoying to wakeup in the middle of the night, just to unplug it
it was awesome the day i found that patch on the forum to disable the annoying pop up alert that your battery is full.
now i can sleep the whole night without the alert coming online, and rest at ease knowing if the phone actually alerts me, it'll be a phone call or something important, not some annoying "unplug me plz!" message

Temperature while charging

hey there..
got my S2 yesterday and had a wave before..
the accu is charging very slow..(from 19% - 100% about 3 hours)
and while it´s charging and i do something with the phone, or without doing sth, too. i become very hot..
is it normal?
newest firmware is on the phone..
greetz

well without telling us what temperature you are reaching we cannot really say, but the phone will get hot if you use it while charging, especially if you make a call while charging.

don´t have opportunity to know what it is exactly..
when i touch if feels like a cup of tee at the time you can drink it first..
what about the charging time?
greetz

MoraX1992 said:
got my S2 yesterday and had a wave before..
the accu is charging very slow..(from 19% - 100% about 3 hours)
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This is pretty normal, Li-Ion-batteries can´t be charged fully under 3h. Devices that claim to charge the battery in just 1 or 2 hours will charge it only to about 80% and then tell it is fully charged.
You can charge a Li-Ion-battery very fast from 0 to about 75-85%, if the power-adapter delivers enough energy this can be done in about 1h.
But to fill the rest up to 100% you need another 2-3h.
Li-Ion-cells are charged in 2 stages.
In the first stage charging is done with a current between 0,5C and 1C. C in this case means capacity, so our 1,6Ah-battery will be charged with 0,8-1,6A.
The voltage of the cell rises from about 3V when completely flat (you shouldn´t discharge a Li-Ion-cell below 3V or it will be damaged permanently, when discharging below 2,7V the cell becomes unstable and could explode when being charged, therefore a safety-circuit should prevent any further charging when the cell-voltage was too low) to about 4,2V.
When the cell reaches 4,2V it is charged to about 75-85%.
If you would charge further at this rate, the cell-voltage would rise even more and significantly reduce the life span of the battery.
The supplied power-adapter delivers 0,7A at 5V, so with some quick calculations it will not be able to charge the battery up to this stage below 1h.
If all the power from the adapter can be used for charging (which means no other phone-activities which will consume power) it can reach the saturation-stage in approximately 1,5h.
To completely charge the battery stage 2 follows, this is also called the saturation-stage.
During this stage the charging-circuit will hold the cell-voltage constant and reduce the charging-current accordingly.
If you want to charge the battery completely the rather weak power-supply doesn´t matter that much (at least as long as you don´t use the phone otherwise and take a significant amount of power away from charging). The faster you charge in stage 1, the longer the saturation-stage will last. The whole charging-time is not influenced a lot.
To fully charge the battery you will always need about 3-4h. Also the difference would not be great whether you begin charging at 0%, 20% or 30%.
Charging the first few % will always be very fast and gets slower the fuller the battery already is. The saturation-stage will take about 50-75% of the overall charging-time, so there is no significant difference whether the battery is completely flat or still has some charge left.
and while it´s charging and i do something with the phone, or without doing sth, too. i become very hot..
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Are you just charging the phone or using it the same time? If you are just charging it, it definitely shouldn´t get hot, charging Li-Ion-cells has a very high efficiency-factor (about 95-99%), so there shouldn´t be much heat generated from the charging.
If you are using it the same time, it is pretty normal that the phone is getting warmer.
It is also important what is getting hot. Is it really the battery (the lower half of the phone) or rather the SoC (which seems to be placed just below the camera)
If it isn´t the battery, it can´t be in direct relationship with the charging. If the whole phone is getting warm, it is an indication, that the SoC is doing some work and generating the heat.
If only the battery gets hot (and not just slightly warm) this can be a problem. Either the charging-current is too high (quite unlikely, with the weak power-adapter) or something else is wrong, which will at least cause a shorter life-time of the battery.
It is normal that the battery gets a bit warmer than the surroundings, especially if the battery is in the early phase of stage 1, where it is charged pretty fast.
While the charging will not produce much heat, the battery is in a plastic-shell, so it can´t be transported away that fast.
But if it gets really hot you have a serious problem. But I doubt this, the phone actually has a protection, that will not charge the battery above a certain temperature-level.

MoraX1992 said:
and while it´s charging and i do something with the phone, or without doing sth, too. i become very hot..
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Click to collapse
If battery gets a little bit hot, it's normal, if you get hot then i don't know

[RETURNED THE BATTERY] New battery, wrong temparature in stats...

Hello, i have bought a new battery and it is reporting wrong temperature which is always -7 c or -8 c. I cant leave my battery in wall charger or in phone to charge, because it may overcharge since its showing a wrong temp value and explode or cause a fire. (also it chargers never report it as"charged", always red led on phone and blinks on standalone charger). I think battery has a malfunctioning thermistor, so i talked to seller and he sent me a new one, but this battery has the same problem. Is there a way to fix this? Battery is not oem , it says oem but it doesn't seem like a oem (poor printing and some differences but it has a serial and manufacturing day on it). Can you guys please help me? I don't know if i should return these batteries.
edit: i forgot to state that baterry can be charged with a external charger. Seller let me keep one of the batteries and it is functioning as expected even it has a wrong temperature reading. I suggest that someone with a battery problem should read musicfanat's post.

cizkek_ said:
Hello, i have bought a new battery and it is reporting wrong temperature which is always -7 c or -8 c. I cant leave my battery in wall charger or in phone to charge, because it may overcharge since its showing a wrong temp value and explode or cause a fire. (also it chargers never report it as"charged", always red led on phone and blinks on standalone charger). I think battery has a malfunctioning thermistor, so i talked to seller and he sent me a new one, but this battery has the same problem. Is there a way to fix this? Battery is not oem , it says oem but it doesn't seem like a oem (poor printing and some differences but it has a serial and manufacturing day on it). Can you guys please help me? I don't know if i should return these batteries.
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Click to collapse
I've never seen a negative temp in a batterie for our phones but i think i would send them back instead.

faustino_pico said:
I've never seen a negative temp in a batterie for our phones but i think i would send them back instead.
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thank you for your reply, i have already returned one of the batteries . i better change my posts header. the one batery im keeping has no charge problem anymore, i dont know what changed but still temp problem exists, im regularly checking it with my hand :cyclops:

In fact the temperature is used only as protecting parameter - to avoid overheating (which sometimes may lead to fire). The only way used to control charge cycle for li- batteries is voltage - charger should stop at 4.2V. Usually, if the charger circuit is fine it will not let the current be so high to heat the battery to dangerous temp. So if it is the thermistor or some other electronic fault then checking temp with hand is reasonable way to control charging.
The fact the charging process finishes also points that battery itself is more or less OK.
By the way, does it provide similar working time as original battery? Is the charging time also similar?
From the other hand you should understand the risk of using battery with any issues. At least you may put the phone while charging to avoid fire in case something goes wrong. (frying pan is not the most crazy idea )

musicfanat said:
In fact the temperature is used only as protecting parameter - to avoid overheating (which sometimes may lead to fire). The only way used to control charge cycle for li- batteries is voltage - charger should stop at 4.2V. Usually, if the charger circuit is fine it will not let the current be so high to heat the battery to dangerous temp. So if it is the thermistor or some other electronic fault then checking temp with hand is reasonable way to control charging.
The fact the charging process finishes also points that battery itself is more or less OK.
By the way, does it provide similar working time as original battery? Is the charging time also similar?
From the other hand you should understand the risk of using battery with any issues. At least you may put the phone while charging to avoid fire in case something goes wrong. (frying pan is not the most crazy idea )
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Click to collapse
It is good to know that it won't effect charging . I am using an external, wall charger for the battery and i haven't noticed any over heat problems in 10 days . It is really weird that i can't charge it with the phone, Also it is lasting really good, a minimum of 6 hours with heavy use (edge connection is always on) and 10 with normal use. I was really afraid that a wrong temparature reading could make the phone unusable.

Wireless charging. Over use of

Is it best to do long charges then let it drain, or is it safe to for example use the phone ten mins and put it back on the mat for ten then use again and so on. Does constantly charging mess things up?
Thanks.

swainclubber said:
Is it best to do long charges then let it drain, or is it safe to for example use the phone ten mins and put it back on the mat for ten then use again and so on. Does constantly charging mess things up?
Thanks.
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Click to collapse
Your phone's battery should be fine as long as it's not overheating.
Most of today's batteries are built to last, which means if you are actually abusing wireless charging, you will start noticing not before 1 year from now(estimated.). And by then, most people have switched their devices. Therefore, it might be damaging you battery, I'm not an expert, but you should not start seeing any bad impact on your phone in the near future.
Other people's opinions might be more helpful than mine, but you should keep this in mind.

Cheers for your opinion. All are greatly appreciated.

guetzli32 said:
Your phone's battery should be fine as long as it's not overheating.
Most of today's batteries are built to last, which means if you are actually abusing wireless charging, you will start noticing not before 1 year from now(estimated.). And by then, most people have switched their devices. Therefore, it might be damaging you battery, I'm not an expert, but you should not start seeing any bad impact on your phone in the near future.
Other people's opinions might be more helpful than mine, but you should keep this in mind.
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Click to collapse
Right on, and by this time next year the OEM batteries will be cheaper and thus just replace them
Sent from my SAMSUNG-SM-G900A using XDA Free mobile app

swainclubber said:
Is it best to do long charges then let it drain, or is it safe to for example use the phone ten mins and put it back on the mat for ten then use again and so on. Does constantly charging mess things up?
Thanks.
Click to expand...
Click to collapse
Almost no one charges batteries the ideal way.. well, because it's inconvenient to do so. Fortunately battery technology is getting better every year, batteries take longer to wear out and are (slowly) getting cheaper to replace when it comes to that.
The ideal way to charge a battery depends on the type of battery. The S5 uses a lithium ion batteries. Ideally you would charge a Li-ion battery slowly, not deep cycle it, protect the battery from hot environments and (idealy) stop charging around 85%.
Heat is the major enemy, battery life is shortened by a factor of two for every 10°C increase above 25°C. High cell voltages and cycling would fill out the top three list of things you'd like to avoid to maximize battery life.
So what does all that mean? Frequent wireless charging is beneficial if your battery charge is < 85%, because you don't want to deep cycle and slow charging (which wireless is) is better than a fast charge cycle for battery life. And a moderate stress if you are charging it when the battery is > 85%. Do what you can to avoid high heat e.g. don't leave your phone in a very hot car on a sunny day if you can avoid it. And if you go Skiing or store your phone in a freezer for some reason.. let it warm up a bit before trying to charge it.
Most of us will charge our phones even if the battery charge is > 85% though because we want to maximize run time, even though the higher voltages above 85% are a detriment to battery life. It's a trade off between utility and battery life. Battery life is conservatively specified around 500 charge cycles these days.. but that is a loosely defined term with a lot of associated variables. Depending on how you use your phone.. your battery may go six months, a year, even two years before you notice that your run time just doesn't cut it anymore.
I'd say don't worry about wireless charging. Charge it as frequently as you like. But try to keep your phone cool (out of the sun) when you can.
.

Cheers for that appreciated. However wireless charging on my setup involves a fair amount of heat

Wireless charging is relatively inefficient. Which means that there will be some waste heat generated. But it varies substantially on the brand of charger and whether you are using an resonant or inductive design. My wireless charger produces minimal heat.
Unless you measure the temperature.. it's hard to gage whether the heat from yours is a serious issue or not. Mine increases the surface temperature ~ 5C.
.

Would you mind sharing which charger you use?
fffft said:
Wireless charging is relatively inefficient. Which means that there will be some waste heat generated. But it varies substantially on the brand of charger and whether you are using an resonant or inductive design. My wireless charger produces minimal heat.
Unless you measure the temperature.. it's hard to gage whether the heat from yours is a serious issue or not. Mine increases the surface temperature ~ 5C.
.
Click to expand...
Click to collapse

lordhamster said:
Would you mind sharing which charger you use?
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Click to collapse
How good are you with Orcad and a soldering iron?
I built my own @ 3.57 Mhz, which is also a non-standard (but very efficient) coupling frequency.
.

swainclubber said:
Is it best to do long charges then let it drain, or is it safe to for example use the phone ten mins and put it back on the mat for ten then use again and so on. Does constantly charging mess things up?
Thanks.
Click to expand...
Click to collapse
Lithium-ion battery nowadays does not have memory effect. So constant recharging and disconnecting is fine.

Cheers folks.

Charging advice

Hello, so I just got a new Moto X style about a month ago, I need your advice from something, should I charge my phone at 30-40%? if yes then will it have long term damage/worn out my phone?
Thank you

The golden rules are
Don't ever go below 10%
The battery is happiest (most chemically stable) around 40%
Try to spend as little time above 90% as practically possible, especially when charging/using the device. This means never leaving the device plugged overnight
Avoid heat i.e., Do not overtax the phone in an environment like a small, hot room; Avoid simultaneous charging/GPS in the car with the phone in direct sunlight
To combine the last two items, especially avoid high temperatures at higher battery levels. This will degrade the battery very quickly
I've also read stuff about the discharge depth. Something to the tune of discharging the battery from 80% to 60% before charging is better than discharging from 80% to 40% before charging. I've never paid that much attention, because nobody wants to charge their phone 3 times a day, but apparently topping up is better than charging from near empty.
I've had my Pure for a little more than 6 months now. I have been consistently plugging in when my battery hits 30%. My battery life is as good as it has always been.

QuantumFluxx said:
The golden rules are
Don't ever go below 10%
The battery is happiest (most chemically stable) around 40%
Try to spend as little time above 90% as practically possible, especially when charging/using the device. This means never leaving the device plugged overnight
Avoid heat i.e., Do not overtax the phone in an environment like a small, hot room; Avoid simultaneous charging/GPS in the car with the phone in direct sunlight
To combine the last two items, especially avoid high temperatures at higher battery levels. This will degrade the battery very quickly
I've also read stuff about the discharge depth. Something to the tune of discharging the battery from 80% to 60% before charging is better than discharging from 80% to 40% before charging. I've never paid that much attention, because nobody wants to charge their phone 3 times a day, but apparently topping up is better than charging from near empty.
I've had my Pure for a little more than 6 months now. I have been consistently plugging in when my battery hits 30%. My battery life is as good as it has always been.
Click to expand...
Click to collapse
IMO charging overnight dont do anything to the battery, phone stops charging at 100% and start to use energy from the charger, but im with you with the 10%.

I think all these "rules" are all just bunk and superstition... If you make it through the day, plug it in overnight, and start again in the morning, if not when the battery is low, charge it when it is convenient, don't be scared of "overcharging" as that isn't really possible anymore with electronics in batteries and devices. The device is meant to be used, not babied.

These lion lipm battery do not actually ever charge to their full capacity. This is by design so 100 % is really around 80 in reality and 0 is around 8 to 10%. Again this is by design the chipset monitors the battery temperature and charge load as well as discharge load and compensates for heat and load. All this crap about charging at different rates and in different situations is bunk written by people that don't realize battery design is constantly changing. And since quick charge 1 things have changed a ton.

RK2116 said:
IMO charging overnight dont do anything to the battery, phone stops charging at 100% and start to use energy from the charger, but im with you with the 10%.
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Click to collapse
Sooo does this mean I can charge my phone over night using the Turbo charger 25W that comes with the phone?

acejavelin said:
I think all these "rules" are all just bunk and superstition... If you make it through the day, plug it in overnight, and start again in the morning, if not when the battery is low, charge it when it is convenient, don't be scared of "overcharging" as that isn't really possible anymore with electronics in batteries and devices. The device is meant to be used, not babied.
Click to expand...
Click to collapse
So does this mean i can charge it over night with the turbo charger?

HerySean said:
So does this mean i can charge it over night with the turbo charger?
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Click to collapse
Yes

acejavelin said:
Yes
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+1
---------- Post added at 06:55 PM ---------- Previous post was at 06:54 PM ----------
HerySean said:
Sooo does this mean I can charge my phone over night using the Turbo charger 25W that comes with the phone?
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Click to collapse
Yes.

I won't argue with anyone here, but I would advise all of you to research lithium ion battery technology. The OP asked how to prevent long term damage to his battery. My friend and I bought our Pure's at the same time. I charge the way that I indicated, he leaves his phone plugged in all night, every night. We're both on Verizon, and I've noticed that his battery drains much more quickly than mine does.
http://batteryuniversity.com/learn/article/how_to_prolong_lithium_based_batteries
Take care, all.

QuantumFluxx said:
I won't argue with anyone here, but I would advise all of you to research lithium ion battery technology. The OP asked how to prevent long term damage to his battery. My friend and I bought our Pure's at the same time. I charge the way that I indicated, he leaves his phone plugged in all night, every night. We're both on Verizon, and I've noticed that his battery drains much more quickly than mine does.
http://batteryuniversity.com/learn/article/how_to_prolong_lithium_based_batteries
Take care, all.
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Click to collapse
Have you verified that he is running exactly the same apps as you with exactly the same service throughout the day. If not then your supposing that charging is the issue is simply a guess. The only way to determine exactly would be a to set them up exactly the same and run them exactly the same in exactly the same conditions for a week or more and log the battery life..

autosurgeon said:
Have you verified that he is running exactly the same apps as you with exactly the same service throughout the day. If not then your supposing that charging is the issue is simply a guess. The only way to determine exactly would be a to set them up exactly the same and run them exactly the same in exactly the same conditions for a week or more and log the battery life..
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Click to collapse
I run more than he does. He is older, and does not use social media. I use FB/Messenger, Snapchat, Twitter, and Instagram with push notifications enabled. Our standby battery drains are very different from 100%. His device hits 90 while mine is reading 94. The devices are physically next to one another. I only know this because he's at my house every weekend. He always plugs my phone in when he plugs in his even though I've told him not to a hundred times. There are probably other factors involved, but I always attributed the difference to him constantly leaving his phone plugged in for hours on end.

Have you looked at his screen timeout? Screen brightness. Or checked to see if he has a misbehaving app? Does he have wifi at his house ? Or is his doing all it's updates at your place? See there are tons of variables that have nothing to do with charging that are simply more likely to be causing the issue you are noticing

autosurgeon said:
Have you looked at his screen timeout? Screen brightness. Or checked to see if he has a misbehaving app? Does he have wifi at his house ? Or is his doing all it's updates at your place? See there are tons of variables that have nothing to do with charging that are simply more likely to be causing the issue you are noticing
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Click to collapse
I mean, I wouldn't describe what I'm observing as an 'issue'. I understand where you're coming from though. I have gone to war against errant battery drains in the past. Lollipop/Marshmallow's mobile radio drain is something I surely won't miss. He does have Wifi at his house for app updates and such.
Just for the clarity's sake, we're talking about:
2 identical devices, running the same version of Android and the same ROM, which are connected to the same mobile and wifi networks, in the same physical location - so service quality is not a variable, unless there is a hardware issue. Both devices are [simultaneously] charged to 100%, and then they are unplugged and their screens remain off. Upon checking both devices a little while later, mine is at 94% while his is at 90%. My device is encrypted, rooted, has custom kernel settings relating to the governor, read ahead, and entropy, and runs various GCM social/messaging apps, and has an extensive Tasker setup. His device is untouched. Both devices have been fully drained and recharged at least once in the past 60 days.
I have looked at his battery usage, which I log with 3C Toolbox. There is no excessive drain from any apps, the cell radio, the kernel, etc...
Regardless of what is causing it, the observable evidence is curious.

QuantumFluxx said:
I won't argue with anyone here, but I would advise all of you to research lithium ion battery technology. The OP asked how to prevent long term damage to his battery. My friend and I bought our Pure's at the same time. I charge the way that I indicated, he leaves his phone plugged in all night, every night. We're both on Verizon, and I've noticed that his battery drains much more quickly than mine does.
http://batteryuniversity.com/learn/article/how_to_prolong_lithium_based_batteries
Take care, all.
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Not saying you are wrong, but the scenario you give is at best circumstantial with the given info. It does not account for other factors such as apps installed, network connectivity, how the phone is being used, etc.

Screen brightness can drastically change how long until you have to recharge. Mine is usually only 1/4 of the way up.