

Should you run your laptop off battery power or use a charger? - kqr2
http://www.slate.com/id/2205761/

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timcederman
Lithium ion batteries work best if they're kept topped up. I'm surprised Apple
recommends draining once a month.

Completely draining and topping up a LiIon battery will kill it much more
rapidly than keeping it topped up.

LiIon will also naturally degrade over time. I think for 90%+ of all lithium
batteries (polymer or ion) the battery life will fall off extremely rapidly
after 2 years regardless of how you treat it. That said, I still have a
handful of batteries that are 5 years old and still work great (for my long-
since-discontinued Sony IP55e MicroMV camcorder)

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pclark
at work we have a few users who never take their laptops anywhere - they're
constantly plugged in. Nothing kills batteries faster.

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davidw
Silly question, but the commentary on whether you should run down the battery
now and then is interesting. What's the opinion here?

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jwilliams
Def a good idea to completely cycle your battery every now and then (i.e. use
till your laptop totally runs out of juice and then totally charge again).

Battery chemistries have improved since the old NiCad days, but they will
still exhibit some memory.

Also, batteries tend to have a lot of smarts in them nowadays - cycling the
battery will let the electronics have a better idea of when the battery is
actually full or empty. This will result in a better charge when you use the
battery for real.

Afaik, that last point is why Apple recommend power cycling your battery every
now and then.

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likpok
"Battery chemistries have improved since the old NiCad days, but they will
still exhibit some memory."

This is incorrect. Lithium ion batteries do not exhibit memory. However, the
digital tools to check them can develop a memory, which leads to inaccuracies.
(and is why it is recommended to occasionally cycle the battery). Cycling is
hard on lithium ion, so you should try not do to it too often.

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jwilliams
> _This is incorrect. Lithium ion batteries do not exhibit memory_.

I said chemistries - NiMH still exhibit a memory.

> _However, the digital tools to check them can develop a memory_

I think I mentioned that.

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moses1400
i always keep my laptop plugged in when home and in use - otherwise it just
sits on the table not plugged in and not on

