Battery expanded and burst open-What caused this?

Hello,


I have an early 2008 MacBook Pro. It still had the original battery in it which a few months ago started expanding. At first I thought it wasn't a big deal but later on it started getting much bigger until the actual casing of the battery popped open. Unfortunately it was installed so slightly pressed into my case where it seems the keyboard slightly raised up.

I went to OWC's website and purchased a new battery for this laptop. It's in there now and seems to be working fine. The keyboard seems to be okay also and my laptop is working perfectly normal.

My question is what caused it? Was it some type of defect or just an old battery? I actually have 3 images that were taken of this battery. The concern I have mostly is will it happen again? I don't want to damage my laptop. Is it possible fan related? I think I can hear the fan running but it doesn't seem to be very loud so I thought maybe one fan (if there's more than one) went out or maybe it's not running as fast as it should. Would this be a fan issue or something else that needs to be fixed? I have thought of making a Genius Bar appointment to have Apple check it out but of course if it's nothing wrong with it I'd rather avoid the appointment since it's a long drive to my nearest Genius Bar.

Thanks in advance for your help.

Boy, sounds like you were lucky, i.e. potential damage to your laptop, plus the chance of a fire or explosion! Hopefully there will not be a next time but if so replace the battery as soon as you notice such a change.

Battery expansion or bloat is a known issue w/ lithium ion (LI) technology, and has led to massive recalls and cost much money - checkout these Link 1 and Link 2.

Now I've owned about a half dozen laptops w/ probably 8 LI batteries and have not had a problem but who knows; I bought my first Apple laptop (MBPro) in March of this year, and the battery is not accessible - have not read the details on this battery (a number of different standards are used to construct these power sources and I suspect some are more prone than others to this problem?).

Hopefully, some of our 'battery gurus' will chime in with more information and advice - Dave

Actually, you should have taken your 2008 MacBook Pro to Apple. Chances are good that they would have replaced the battery for free even though it was long out of warranty. We have had several members of our forums who experienced the same thing and Apple replaced their battery without charging for the replacement or labor.

LIon batteries don't like to be treated like NiCad or NiMh batteries, so when they were newer and people didn't know, they tended to do the deep discharge, heavy use treatment and drove the batteries to failure. LIon batteries like to be kept topped up and gently used. And all LI batteries begin to decay as soon as they are made, with the decay becoming noticeable about two years after manufacture.

So, to lengthen the life of your battery, keep it topped off and try not to discharge it too deeply too often. A "cycle" of the battery is defined as discharge from full to depleted and back up to full. A LIon battery has about 1000 cycles life. If you start with a full charge and only go to, let's say, 75%, then recharge to 100%, then that is a quarter cycle. Four of those add up to a full cycle. So keeping the battery above 75% should extend the life in calendar months as you are using cycles more slowly. (The numbers are not EXACT, as there are many factors in battery life. However, the general principle is valid.)

Apple recommends a full discharge once a month. That recommendation is not for the battery, but to recalibrate the battery meter to the new battery condition as the battery ages. I think they looked for a compromise between the anticipated life of 1000 cycles or so and the need to recalibrate the battery. Once a month is not a bad compromise.