Does using AC Power most of the time affect battery life?

It is not recommended to remove the battery. In fact, the processor will run at a reduced speed, and if you were accidentally remove the magsafe or have a power outage, your machine would slam down, which is not a good thing.

It is a good idea to run the battery down every so often, but other than that, your battery will be fine the way your using it. I use mine mostly on AC, and my battery still reports 100% health after 7 months of owning my MacBook.

Len D wrote:
It is a good idea to run the battery down every so often, but other than that, your battery will be fine the way your using it. I use mine mostly on AC, and my battery still reports 100% health after 7 months of owning my MacBook.

Apple has an iCal reminder at the beginning of each month to operate off of battery power.

100% health isn't unusual after a couple of years of service and operating off of battery power once a month. The battery health will inevitably go down if the battery is used every day after a few hundred cycles. There's no way around it with any lithium rechargeable battery. A few years of simple aging with also result in loss of battery capacity. That's the consequence of using a lighter and more power dense lithium rechargeable.

I also have a Black MacBook and I was curious how you can check the life and usage of your battery?

Also from what I have read in this forum it seems like it doesnt matter if you run your laptop off of your AC adapter whenever you feel necessary but it is a good idea about once a month to just let it die down and recharge it correct?

Sorry but I am a first time Mac User and just want to get the full life out of my laptop.

I appreciate all of your guys input!!!!

Correct - run the battery down once a month or so. Also callibrate your battery once a month or so as per the Apple guidelines:

http://support.apple.com/kb/HT1490

You can check on the health of your battery by clicking on the Apple logo, top left of your screen, go to About this Mac, click then on More Info, and on the Power section of the Hardware section you will see how many charge cycles etc you have been through.

If you remove the battery, the MacBook won't run at full speed (at least with the old MacBook's).

I don't think that having your battery fully charged all time (by having your MacBook permanently connected to the AC charger) is a good thing for the battery health, but I guess that calibrating it once a month should be enough to keep it healthy.

+*I don't think that having your battery fully charged all time (by having your MacBook permanently connected to the AC charger) is a good thing for the battery health, but I guess that calibrating it once a month should be enough to keep it healthy.*+

Actually, leaving your battery in while on A/C will prolong, not lessen the life of your battery. The charging system does not constantly keep the battery charged to 100%. It intelligently maintains the charge in a way most efficient to prolong battery life. The battery will charge to 100%... and then stop charging... it will not start charging again until the capacity runs down to about 95%. These very small incremental charges (5% increments) mean that it would take about 20 of these 5% cycles to equal one full cycle (which is much better than doing a full charge every few days). The quicker you get to the 300 cycle point, the quicker you'll start to lose capacity. It's a good idea to calibrate every two months or so (I personally think once a month is too frequently).

I didn't know that, that very good. However, I readed that it's best to keep Li-on battery's at 40-60% charge to prolong its life.

Now I just decided to enjoy my MacBook and forget about the battery life 🙂 I just try to follow Apple's recommendations (1 year old MacBook, ~96% health, ~4800 mAh, ~100 cycles; I only charge the battery when it's low, and calibrate it every 1-2 months).

chasan wrote:
I didn't know that, that very good. However, I readed that it's best to keep Li-on battery's at 40-60% charge to prolong its life.

Now I just decided to enjoy my MacBook and forget about the battery life 🙂 I just try to follow Apple's recommendations (1 year old MacBook, ~96% health, ~4800 mAh, ~100 cycles; I only charge the battery when it's low, and calibrate it every 1-2 months).

Technically keeping almost any rechargeable battery between 40-75% charge is ideal for ultimate longevity. It's the extremes of charge and discharge that result in greater loss of battery capacity. I've been told that "100%" for most li-ion batteries is not actually that, but less than 100% of the theoretical capacity for a safety margin when charging. I don't know how many people remember the Sony factory which manufactured most of the world's li-ion batteries in the mid-90s. There was a massive explosion in 1995 that took out the factory. I had a coworker who used to work for a PC company and said that the head of their battery research would be sure to leave the battery charging room quickly just in case a battery ruptured.

Hybrid car batteries can typically go through over 100,000 cycles where they get charged between 40-75%. However - they always have power sources available in the internal combustion engine as well as the regenerative braking system (essentially a generator) to keep them from ever having to dip below the 40% level. I've heard of some hybrid car owners who ran out of fuel and tried to use "limp mode" to get home rather than to the nearest place to refuel. After the battery got depleted to near 0%, it was no longer usable for the purpose it was intended for. It wouldn't properly take a charge and needed to be replaced. It wasn't handled under warranty because overuse of the limp mode was considered abuse.

That kind of charging scheme wouldn't make sense for portable electronics. Most people want to be able to get hours of reasonable usage from a battery without having to find a place to plug in to keep it from dipping below 40%. Computer makers like to be able to advertise long times for use off a single charge. I've had to replace the battery in my cell phone after a few hundred charge-discharge cycles.

Lithium ion batteries also have a problem in that they lose capacity due to age no matter what you do.