How much damage does 'over charging' my mac cause?

I am pretty sure that you are misinformed, there. Holding the power cord in only keeps the laptop from running off battery once it is fully charged. You have nothing to fear…

It knows when your battery is full and stops supplying power to it.

The idea of you sitting there waiting for it to reach 100 and pulling the plug is surprisingly amusing.

@johnpowell Haha I just imagined someone staring with a very concetrated gaze at the computer screen waiting for the exact moment when it hits 100, then jumping out and pulling out the wire quickly. I laughed :)

Besides if you’re using a laptop while the charged status has reached 100% the energy that is running through the cord is used to run the computer; It still uses energy does it not? This is why the battery life remains at 100.

Of course the battery life can be damaged over a period of time of constant use of powering repeatedly. You shouldn’t worry about this though, it takes a looong time before it malfunctions. If you’re really worried… take out the battery and leave the cord plugged in while you use you macbook, the only source of its energy.

@johnpowell well obvioulsy I don’t sit there like OMG NOW? NOW? NOW?
I could tell you who told me… what’s it worth to ya’? ;) the answer is surprisingly amusing

richardhenry

shush damnit…

Right.
so after reading on a few mac forums here’s what I’m getting.
My source cough@richardhenrycough is right – sort of.
If you keep the charger plugged in overnight etc and it will reduce battery capacity over time.
However, you don’t need to take the charger out every time it reaches 100%.
You could keep it charged and plugged into the mains as long as you cycle (let the battery run to zero) the battery every week or so.

I’ve heard this as well… but more that if you never leave your battery unplugged you can condition it and it loses capacity. See http://www.apple.com/batteries/notebooks.html

Of course, Apple batteries seem to die within a year anyway… so…

Well there you go. They say cycle once a MONTH!

@andrew Mine lasted three years before suffering significant capacity loss, and then they replaced it for free. My iPod, which is also about three years old, is still doing fine as well.

They say you should do this every month or few, as well.

@damien thank you very much. That is incredibly useful. GA’d

I bought a new battery today. My battery was 2.5 years old, which the Applecare phone line say is around the time the average battery will have reached the end of its useful life.

In terms of charging beyond capacity, as JohnPowell says, it knows when the battery is full and stops charging.

I say it’ll diminish your overall battery life 2 too 3 months. But I think that’s a good trade off for the convenience of always having your laptop ready to go.

Also! The new MacBook’s (Unibody Aluminium) performance goes way down when you take out the battery and run it just off the wire. Something to do with the charger not being able to supply the juice.

I noticed some people mention removing the battery and running only off the power
cord.

I would say that is a bad Fluther response.

You should not run your MacBook off the power cord with the battery removed!

Here’s an article for those with doubts. Best of luck!

http://support.apple.com/kb/HT2332?viewlocale=en_US

@benchaos I often run my laptop with the battery removed in order to keep the laptop cool. Given how much of a difference this extra ventilation makes, the reasons cited in your linked article aren’t too compelling for me. (Also, heat is just about the worst thing you can do to a battery, which is another reason for me to want my battery away from my over-heated laptop—which isn’t over-heated once the battery is gone.) I don’t have any speed problems doing this.

@aidje – I for one agree with ben (and Apple, for that matter) that it’s not the best of ideas given the drop in processor speed and potential for data loss if the cable is tripped. What you do with your own laptop is up to you, but I wouldn’t go recommend any approach that lower performance and come with risks from the manufacturer themselves,

@benseven – Let me re-summarize: 1) My MBP gets crazy hot and can really use some extra ventilation. 2) The performance drop is entirely negligible under normal use. 3) There is almost no risk of the MagSafe popping out while the laptop is on my desk, which is up against a wall.

I understand the concerns, but there’s no reason to be treating me as if I’m taking some huge risk.

I’d recommend getting a ChillMat for your laptop if it’s getting “crazy hot.” I have one for my MacBook and it keeps the laptop cool and it’s relatively inexpensive. Mine is produced by Targus.

Unfortunately, I haven’t been able to find a cooling pad with reviews positive enough to convince me that it’s worth spending $25 – $50. The reviews for the one you mention say that the laptop is always sliding off (not to mention that it’s apparently made for the 17’’ and not the 15’’).

That’s weird people would say that considering the one I use form Targus has rubber grips, and mine is for the 13” MacBook.