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[_] correct treatment of laptop batteries

Tom Gidden tom at
Sat Dec 19 12:34:03 GMT 2009

On 19 Dec 2009, at 12:21, Jon Bennett wrote:
> I've heard it's a good idea to take the battery out if you're running
> from the mains for extended periods of time. I've not gone this far
> though (powercuts and no batt is bad IMO), but do often charge up then
> run down since I had to replace my battery.

Problem is with the MagSafe power connector, it's far easier to lose mains power unexpectedly.  On the other hand, MagSafe has saved my MBP from certain destruction (well, damage) several times.

So I wouldn't want to take out the battery: it's effectively a poor man's UPS.

Batteryuniversity is a good site, but I've seen alternative views of this issue (none of which I can find right now), coming to the conclusion that regardless of how you treat the battery, as Ray says, it's going to die. 

There's a LOT of myth, FUD, anecdote and nonsense out there, and Apple are quite guilty of it too... their battery advice isn't always consistent, and clearly hasn't been updated since NiMH at some points.  I wouldn't recommend taking their in-store "Genius" advice, or their web-based advice as gospel.

Over the space of 18-24 months, the hassle of being prissy about battery usage; discharge cycles; etc. is going to be more of a problem than just budgeting for a new battery every few years.  Compared to the ~£2000 initial spend on a top-end MBP, it's minor.


Tom Gidden