...bizarre!

Some of you seem skeptical about why anyone would want to remove their battery from a MacBook during use with A/C.

In case you haven't heard, it's because continued attachment of a battery to the A/C source degrades the battery over a long period. Removing the battery when you're on A/C power, i.e. when you do not need the battery, actually extends the lifespan of the battery.

Hence, this piece of news is not as silly as it sounds, if you were not aware of this.

JS2008, you've used too many cheap chargers for all those AA NiCd batteries in your toys. Yes, left on a poorly designed charger it will eventually cook your batteries (NiCd), but Lithium Ion batteries have VERY strict charging requirements. Once charged they cannot sustain a "trickle charge" like most other batteries require to maintain their charge, and the charger must totally disconnect from the battery once full. Even cheap Li-Ion chargers do this and I'm sure Apple's charger does it too.

On every Apple laptop I've ever seen, leaving the computer plugged into AC for extended periods with the battery inside always degrades the battery life more than not doing so. This hasn't changed over the years, and has nothing to do with cheap chargers, unless what Apple uses is 'cheap'. I have many friends with iBooks and MacBooks and the ones who make a habit of leaving their machines plugged into AC with the batteries inside, to a man, end up with crappy battery life within less than a year. Be forewarned, and don't trust assurances from the manufacturers. For you this is anecdotal but I'm a Mac consultant and for me this is based on years of hard experience: if you want your battery to last, do NOT regularly leave it attached to the wall for much longer than it needs to charge fully. The alternative is to always unplug it or to remove the battery and (in Apple's case) take the performance hit.

So, apparently, according to the crowd of "everyone's looking to bash Apple", anything that was announced at any point in time should be known by all users/owners, regardless of the time that has expired since it was announced, or the fact that new products have been released.

First, not 'everyone' knows this. And I'm sure after this was put up on Gearlog and here, there will still be a majority of mac laptop users who won't know this. Not everyone reads tech stories every day. Most users, in fact, don't.

Second, just because it was true in the previous model doesn't mean it is true in the current model. The previous iMacs had bulging capacitors. Should we assume all iMacs still have these?

Finally, bear in mind there are a lot more users of Mac products now than there were 2 years ago. So, to those people, this would be news.

Now, if MacNN posts it again next month, than it isn't news.

I have been seriously considering the purchase of a new Apple laptop. I was hoping to use it on-the-go, but also as a desktop replacement. Have said that, the news from this article is new for me. I follow-up on Apple news as best I can too (I'm a big fan).

I have read many reviews on Apple's new laptops (even the previous generations). I have never encountered a review which talks about this issue. To be honest, I'm surprised by this news of lower performance because the battery is removed.

Does Apple intend on fixing this issue, ever? How come so few sources and reviewers have mentioned this?

Permanent capacity loss of lithium-ion is a function of temperature and charge level.

There is two things that affects the life of a modern lithium-ion battery.

1) Temperature
2) State of charge.

A laptop on mains is a very hot environment for a lithium battery at full charge. It will loose about 30 - 60 % of it's capacity within a year.

The same battery stored in the fridge at 40% charge level will only loose about 5 % after a year.

Please see http://www.batteryuniversity.com/parttwo-34.htm

Removing the battery to the fridge when operating on AC in longer periods doesn't seem that far out an idea after all !

Best, Henrik