Using the iPad (or a notebook) while it is charging generates a lot of additional heat, which is bad for the battery.
False. After owning every iteration of iPhone, and an iPad 2 and iPad 3, I've not experienced this "excessive heat" caused by charging alone.
Charging a device in an environment where there is a lot of heat to begin with will result in a hot device, but the environment alone is not good for the device to begins with.
And in any case, there are protection mechanisms in the devices themselves they prevent charging, and even operation, when extreme temps (both cold and hot) are detected.
But charging alone, to any level, is not harmful to the device as long as you're using good quality OEM chargers. Not because of heat, current, or anything.
It has also been shown that if you have the brightness up and/or are running intensive apps, the 10W charger cannot supply enough power to properly charge the iPad battery, and in some cases it may actually continue to drain the battery. And if you're in that situation, the A5x is putting out a lot of heat (relatively) in addition to the heat from charging.
The number of "intensive apps" which do this is pretty small, and you'd have to be actively using them for it cause an issue. Again, while the net flow of power might result in a battery drain in those limited cases, the worst that will happen is that you'll be inconvenienced when your iPad powers down... in which case you stop using the iPad and let it charge. The problem has then corrected itself.
But again, charging isn't the problem here. The power drain on those "intensive apps" will be present whether you're plugged in or not.
Unless you have a need to use the iPad while it is charging, for example, being down to 10% battery and still needing to use it for a while, you will have better battery life over the long-term if you do not.
There's absolutely nothing that says this is true. 1000 charge cycles is 1000 charge cycles, whether you use your iPad while plugged in or not.
Apple says to perform at least one charge cycle per month. The basic example of what a charge cycle is, was a poor choice in my opinion.
I respectfully submit that your
opinion does not trump Apple's
facts about charging and battery care.
In the more detailed section on battery terms, they explain that their batteries do not have a "memory" meaning that you do not have to discharge to 0% and back up to 100% for optimal battery life as you did with older rechargeable battery technologies, and go on to explain that a battery cycle is accumulative. (so 2x 50%, or 4x 25% etc. = 1 charge cycle)
Correct. But that doesn't infer that you must never, ever, fully discharge your battery. Either use case is perfectly acceptable.
Yes, the iPad charger will continue to discharge, and then "top up" the battery when it is left at 100%.
Uhh no. The iPad charger doesn't discharge anything. At 100%, the
iPad will stop drawing power to charge the battery, at which point some battery power may get used to run the iPad.
Then, once the battery drops below a certain threshold, it will begin drawing power from the charger to charge the battery back to full.
Is this a problem? Well, as you've astutely noted, battery cycles are cumulative. So, using the iPad this way is no different from unplugging the iPad, using the battery for a while, and topping it up again. In other words: not harmful.
It's not good to leave it in this state for extended periods of time. Assuming you don't need 100% of the battery the next day, it's far better for battery life to leave it at 90% and then do a bigger charge to 100% next time. I never said it was essential, just that I would recommend that, rather than doing unnecessary short trickle-charge cycles on it.
The device vendor clearly doesn't see a specific behavior like that as being necessary. You are over thinking the care and feeding of the battery. If it makes you feel better to do that, then it's not harmful. But telling others that deviating from your behavior is harmful, is just plain not true.
In the notebooks section that you linked to, Apple specifically states:
For maximum long-term battery lifefor example over the space of four or five years as I mentioned with one of the MacBooks here, rather than the space of a product cycle (e.g. 1218 months, where you may not see much degradation) you should never use a portable device while it's plugged into the charger unless it's necessary.
What you're saying is completely different from what Apple says. The document is very clear that the battery SHOULD be used, but plugging in your macbook isn't inherently going to kill your battery so long as you periodically use the battery to keep the electrons moving.
I'm only offering my advice here as someone that has owned several Apple notebooks, and multiple batteries for most of them, such as having two MacBooks that were purchased within six months of each other, where one has 93% of the original capacity after 53 months and almost twice the rated charge cycles, and the other is on its second battery and is almost certainly well below 90% capacity again less than a year after replacing it. (because it's frequently used while it's still plugged in to the charger and always topped up to 100% and left there)
That's funny, because I have a couple of notebooks as well: one that gets a lot of travel, and one that is plugged in more than it's unplugged. Both are 25 months old, and are at 95% and 96% health, respectively. The former has 540 charge cycles on the clock, and the other, 97.
My previous run of MacBook pros, bought back in early 2007, were pretty much the same.
Following the "do a full charge, discharge to 0% and charge cycle once a month" mantra that's posted on the forums here, caused the battery of my MacBook Pro to prematurely lose capacityso much that Apple were happy to replace it free of charge, despite it being a "consumable".
They replaced it despite it being a consumable probably because that's not expected or typical behavior for a notebook battery.
