An Applecare supervisor told me that:
(1) I should not let my iPad 2 run out of power while the system running, because that crashes the software and apparently creates some risk.
(2) I should never run the battery down to zero voltage. He said that iPad 2 batteries should never be completely discharged, and recommended NOT going below 20%.

However, see this web page:
Apple - Batteries - iPad
Where, I quote, it says:
"For proper reporting of the battery’s state of charge, be sure to go through at least one charge cycle per month (charging the battery to 100% and then completely running it down)."
The advice I just quoted seems to encourage running the iPad charge down while the software is live, and definitely seems to suggest running the battery down to 0%.

Who is right? The battery page, or my applecare supervisor?

Absolutely follow the Apple advice. For more technical information look here...

Charging Lithium-ion – Battery University

Tim

Originally Posted by Tim SPRACKLEN

Absolutely follow the Apple advice. For more technical information look here...

Charging Lithium-ion – Battery University

Tim

Good article Tim, thanks for that.

Sent from Wales, using my iPad & iPF.

Originally Posted by Tobyr21

An Applecare supervisor told me that:
(1) I should not let my iPad 2 run out of power while the system running, because that crashes the software and apparently creates some risk.
(2) I should never run the battery down to zero voltage. He said that iPad 2 batteries should never be completely discharged, and recommended NOT going below 20%.

Terrible advice from the supervisor.

(1) The system will auto shutdown when the battery gets to a certain threshold - the battery is not completely empty at this point but the system will close down running apps (saving their state) and then power off to save the integrity of the system.

(2) As per above, the battery is not actually hitting zero voltage, it is calibrated to power down before then - even though the battery meter may say 1% remaining, there is actually more power available - this 1% is just how much running power is available before it shuts down. As per Apple's docs, you need to use the range from 100% down to 1% occasionally for the battery meter to be able to calibrate properly based on your usage. This isn't an exact science, it's an estimate based on what you are doing and what you have done previously.

He told me essentially what this thread advises.
Thanks.

Here's what Apple has to say about the batteries they use in the iPad: ---> http://www.apple.com/batteries/ipad.html

Originally Posted by jwt873

Here's what Apple has to say about the batteries they use in the iPad: ---> http://www.apple.com/batteries/ipad.html

That link was already in the original post.

Sent from my iPad using iPF

The Apple battery page suggests that it's not a good idea to keep the battery charging at 100%. That might mean that we should be careful not to overcharge our batteries. But it could just as easily mean that when the iPad SAYS it is at 100%, the battery is not really 100% and the iPad is being careful not to fully charge the battery.

To put it another way, when the iPad says the battery is 100%, does that really mean the iPad has allowed the battery to reach its physical maximum charge?
Does anybody know?

There is no issue in keeping the battery charged. Why Apple wants you to let it run down once in a while is so they can calibrate the percent charged indicator.

As the battery slowly loses its ability to retain a new-battery full charge, the need to adjust this increases. If you let the battery go flat once in a while, the next full charge will reset the 100% indicator.

That's all the document addresses, not actually the health of the battery.

-t

Originally Posted by Tobyr21

T That might mean that we should be careful not to overcharge our batteries.

You can not over charge your battery.