[seaofcrap]

Seriously. According to iStat Pro the battery health is only 98%. Same thing apparently, according to "About This Mac". Is this normal? My MBP is only 2 days old...

[Big Mac]

It's normal. It happens occasionally on every laptop I have ever used - Mac and PC. It's nothing to be concerned about, in and of itself.

[Simon]

As long as it stays at ~98% everyhing's fine. If you'd observe that the number deteriorates quickly you could have a bad battery. In that case you'll get a free replacement while the MBP is under warranty.

Check out this page:
Apple - Batteries - Notebooks

Basically Apple claims their notebook batteries should retain 80% of their capacity during the first 300 cycles. Note that a cycle is defined as fully discharging and recharging the battery once. A cycle is not the number of times you hook up the charger.

[ghporter]

My battery fluctuates at or above 96% charge when fully charged. It gets cycled now and then, so it's not showing "100% health" in any application, but the health (97% I think) is consistent with the number of cycles so I'm not worried about it.

[Eriamjh]

I use XBattery to track battery capacity.

When attached, the power adapter will trickle charge to 100%, then shut off and let it discharge to about 95% before doing another trickle to 100%. (Or something like that...)

[squeeks]

mine was at 97% now its back to 98% it also says i have 11 cycles but ive never run the battery dead, only to about 20 minutes left, then recharged it

[ghporter]

Cycles are cumulative. Running the battery down to 80% five times equals running it down to 0% once, and that's one full cycle.

[Waragainstsleep]

If the OS reads the capacity at full charge to be less than 100%, this is not unusual. If it goes below 96% or so when fully charged, you should charge it right up, then run it flat, then charge all the way again. This will re-calibrate the meter. The battery/Mac measures the remaining charge by tracking the charge which goes in and out of the battery. It cannot measure the remaining charge directly, so sometimes it goes a little off. Perfectly normal though.
Only the recent Intel 'Books display vattery health and cycles in system profile. Apple is asking for trouble doing this if you ask me.

[Brien]

Well, sometimes it helps. I just had my Blackbook's battery replaced under warranty. It was at ~400 cycles and near 50% of the original capacity. Oh, and it wouldn't charge, so I *had* to run it off AC a lot of the time.

Anyway, 98% is within normal parameters, don't worry.

[Simon]

Reading a constant 96% when plugged in doesn't necessarily mean you need to calibrate.

If you plug in a battery with 98% charge the adapter will not charge the battery. The battery will remain at 98%. There's a deadband above 95% in which the battery isn't charged. If you then unplug your MB(P), use it till you reach something like 90%, and then plug it back in you'll see it will start to charge until it's full. The deadband is intentional. This is the way it was designed to be. Nothing to worry about.