OP specifically stated that he was under the (mistaken) impression it is good for a phone's battery to let it drain. We are discussing that point.
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Should I leave iPhone plugged in when tethering?
- Thread starter PowerMan572
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Charging advice based on old battery technology just won't go away. Lithium ion batteries (ie. the type of rechargeable battery used in all modern mobile devices) can be charged and discharged at will with no problem. Partial charges are fine. There is no benefit to waiting until your battery is drained before you recharge, you don't have to charge all the why to 100% every time, and keeping it plugged in at 100% does no harm.
In terms of charging, there's not much that you can do that will harm your battery or your phone.
NiCd/NiMH batteries have "memory effect" and discharging and recharging them is called "reconditioning" - not recalibration.
Li-ion batteries have charger controllers. The controller doesn't let the Li-ion cell fully discharge or overcharge. Li-ion battery controllers need to synchronize with the battery from time to time, which is called calibration. And calibration has benefits for the battery.
As for iPhone, Apple says calibration is not required for "portables with built-in batteries."
OK well people (not you) are using the term calibration on this thread to mean reconditioning.
How does one synchronize the Li-ion battery controller with the battery?
And are all Li-ion batteries the same - i.e., is there a difference b/t a Li-ion-polymer battery and the other kinds of Li-ion batteries (whatever they may be)?
And if you discharged a Li-ion-polymer battery to 5% and then turned the device off and let it sit there off for months, how could the controller stop it from draining to zero over time?
Calibration is a ritual
, once the device shuts down you plug it in and leave it connected until the battery is fully charged.If you're not going to use it for months, it's recommended to leave it at 40%, not 5%...
How is that different from reconditioning?!?!!?!?!Calibration is a ritual
Right b/c if you leave it at 5%, it will discharge down to zero b/c there is no way for the controller to stop that when it is off.
The controller prevents a full discharge when the device is on, by turning it off.
Reconditioning is slowly and deeply discharging a nickel battery.
And once it is off, the controller can't stop the device from continuing to discharge down to zero. And letting a Li-ion-polymer battery discharge down to zero is very bad for it.
That is all I am saying.
Calibration is recommended for Li-Ion batteries. Latest Apple portables doesn't require it.
Without calibration the controller might over-estimate the actual capacity of the battery and let it discharge beyond safe limit.
In practice it's not, but in effect very much so. Conditioning the old Ni-Cad batteries actually did improve their capacity. "Calibrating" does nothing for a Li-ion battery. In theory it just helps the software report a more accurate percentage measurement, which may make it appear that battery life has improved.
If I let my Li-ion battery get discharged to the point the controller shuts it off automatically, I am not hurting my Li-ion battery's life? As opposed to never letting it get that low?
To the OP yes your apple laptop charges to 100% then lets the battery drop back to 95 and then trickle charges back to 100%
You, however, won't see it at anything other than 100% at that point (normally)
This is why you'll always get charge cycles on it.
You, however, won't see it at anything other than 100% at that point (normally)
This is why you'll always get charge cycles on it.
I had a MacBook Pro 15 for a couple of years and always kept it plugged in and after two years still only had the original 1 cycle on the battery.
Which, as explained above, does nothing for any battery made in the last decade.
No wonder this battery thing is "argued" so many times in this forum as there are so many different answers given in this thread!
I used to be all OCD about when to charge and discharge and based on my own experience and seeing the abuse my wife's iphone 5 battery takes I believe it doesn't make a whole lot of a difference how or when you charge your phone! Some battery's are better than others basically!
She drains her battery to zero quite often because well she only charges it when she really has time to! Pretty much 4 or 5 days a week I hear her say, "it's dead" or "almost dead" and she puts it on the charger sometimes only long enough for it for it to come on at 4-10% and she's using it again! Most nights she will leave it on the charger however. If anybody has "bad" charging habits it's her! I checked her battery health one day and it has like 850 cycles or so and its still at 85% health or so and she's still getting a good 6-7 hours or more on screen time of usage out of it on iOS 6.1.3! (She won't upgrade which actually turned out to be a good thing!)
So really going all OCD about taking care of your battery no matter what you are doing with it probably in the end doesn't really matter IMO! You will just be wasting time stressing about something that you don't need to stress about! Just use it and charge when need be!
She drains her battery to zero quite often because well she only charges it when she really has time to! Pretty much 4 or 5 days a week I hear her say, "it's dead" or "almost dead" and she puts it on the charger sometimes only long enough for it for it to come on at 4-10% and she's using it again! Most nights she will leave it on the charger however. If anybody has "bad" charging habits it's her! I checked her battery health one day and it has like 850 cycles or so and its still at 85% health or so and she's still getting a good 6-7 hours or more on screen time of usage out of it on iOS 6.1.3! (She won't upgrade which actually turned out to be a good thing!)
So really going all OCD about taking care of your battery no matter what you are doing with it probably in the end doesn't really matter IMO! You will just be wasting time stressing about something that you don't need to stress about! Just use it and charge when need be!
And may actually harm it.
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I just buy AppleCare+ and then never think about it.So really going all OCD about taking care of your battery no matter what you are doing with it probably in the end doesn't really matter IMO! You will just be wasting time stressing about something that you don't need to stress about! Just use it and charge when need be!
It keeps my battery in good condition and I get correct battery levels reported to me.
I have a magic rock that keeps tigers away. I've never been attacked by a tiger even once.
