Battery cycles


Nov 21, 2009
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A Dell tech once told me that batteries have a certain amount of "recharging cycles" over the course of it's lifetime. So he told me that I should plug in my computer until my battery is at 100% then unplug until it's nearly completely empty then recharge again.
So I'm wondering if this is the same case with phone batteries. When I'm at home I usually plug my TB in either to the computer(awake) or the wall charger overnight. Should I be plugging in the phone all the time, even if it's fully charged or does that decrease battery life overall and in the short-term for daily use?
That was the case with older style rechargeable batteries.
So for the new ones it doesn't matter? It won't hurt the battery to keep it plugged in even when it's fully charged?
Someone posted a really good article on what impacts battery life a few weeks ago. Can't find it, but the big takeaways are that...

Yes, batteries have a limited shelf life and that one of the things that determines the shelf life is how often it is cycled.

That said, the two things that made a bigger impact than frequency were actually depth of charge (?) and temperature.

I'm paraphrasing the depth of charge term, but basically what this meant was -- not how often you charged your phone, but how often you charged your phone from a low battery %.

Batteries that were fully depleted and then recharged fully saw more battery charge loss over time than batteries that remained full or near full. Or put another way, the old traditional thinking of fully draining your battery before charging was actually worse for your battery than leaving it on the charger all the time.

But the thing that had the MOST impact on battery was actually heat. Batteries exposed to higher internal and external temperatures had much more significant charge loss. They even called this out as the reason that most laptops (which generate a lot of heat) last a mean time of 2-3 years.