Battery life dropped considerably on Mountain Lion.

I just checked it says my battery's cycle count is only 98.

Battery Information:

Model Information:

Serial Number:

Manufacturer: DP

Device Name:

Pack Lot Code: 0

PCB Lot Code: 0

Firmware Version: 201

Hardware Revision: 2

Cell Revision: 158

Charge Information:

Charge Remaining (mAh): 2772

Fully Charged: No

Charging: Yes

Full Charge Capacity (mAh): 2801

Health Information:

Cycle Count: 98

Condition: Service Battery

Battery Installed: Yes

Amperage (mA): 300

Voltage (mV): 12083

Same here, I noticed the battery performance dropping significantly but since I'm normally just at work or at home, it never bothered me until I saw "Service Battery" on the menu this morning. Problem with this, I can't buy a new battery while the service center checks on my current battery like the older MBPs.

Just chiming in too

Mid 2009 MBP, Upgraded to ML last week

Not only did my battery go down from an average of 6hrs down to 2, its now reporting a service battery:

Model Information:

Serial Number:

Manufacturer: SMP

Device Name: bq20z451

Pack Lot Code: 0

PCB Lot Code: 0

Firmware Version: 3

Hardware Revision: 2

Cell Revision: 100

Charge Information:

Charge Remaining (mAh): 2392

Fully Charged: No

Charging: No

Full Charge Capacity (mAh): 3846

Health Information:

Cycle Count: 301

Condition: Service Battery

Battery Installed: Yes

Amperage (mA): -854

Voltage (mV): 11293

Welcome to the club! I forgot to get Apple Care for this one as I was too excited for the new one with Retina Display...problem is I want a 13 inch instead of 15...now my problem is if I should wait for the new one to come out or just get a new one now.

Interesting. Both you and PeterBacani are showing cycle counts that are way below the expected lifespan of those units (1000 cycles in both cases, according to http://support.apple.com/kb/HT1519?viewlocale=en_US&locale=en_US), and both of you are showing battery capacity that's very nearly a factor of two lower than what I'd expect for those units.

It is possible that both your batteries are defective and just happened to fail prematurely, but it is also possible that there's a bug either in the OS or in the SMC firmware such that for some reason, the actual battery capacity is being grossly misreported.

Things to do:

1. Try an SMC reset. If that cures the problem, even temporarily, then it seems likely that the new OS is somehow tickling an SMC bug.

2. Try installing Lion on an external hard drive, do an SMC reset, then boot from the Lion drive and see if the problem persists. If the problem goes away, it's an OS bug.

If the problem persists even after an SMC reset while booted from a Lion drive, then you both got really unlucky, and your batteries just happened to fail prematurely at about the same time as you installed the new OS, in which case you would be wise to not play the lottery or go skydiving. 🙂

2 cents of hope:

The battery life on my mid-2011 MBP dropped 30% from a comfortable 6 hours to a miserable 2 hours after I installed ML the day it launched. The first thing I did was to check Activity Monitor, which showed nothing. The fan was making heckalotta noise too.

Fast forward to today, I checked Activity Monitor again, and I saw a program called vshieldupdate being run by root taking up some 99% of CPU. I force-quit it, and unplugged the power adapter. It was at 100% when I unplugged it - and it's been exactly 25 minutes since that happened - and my battery shows 94% full - 7:06 remaining (I am skeptical about this though). I am going to leave it on and let it drain to give me an idea about its life. The fan noise has stopped too.

I understand vshieldupdate ships with VMware tools. I am puzzled because I never installed any VMWare software. Does it ship with Mountain Lion?

Edit: After a bit of googling, I realized vshieldupdate ships with McAfee. Has it been causing battery issues for anyone else?

I'm running the MBA (Mid-2011) model (more expensive 11" model) and I used to get a good 5~4.5 hour battery life off my MBA while using Lion... did the upgrade and immediately my battery life dropped in half.. I'm lucky to get 2.5 hours now even with wifi off and screen to minimal brightness. I really hope Apple fixes this soon.

Did the reset...didn't do anything. Too busy to do external HD installation because its my birthday...What a nice present from Apple 😢

Not for anything but I changed Energy Saver Preferences before I got the Service Battery warning...

Try booting Lion and make sure that the problem is, in fact, hardware. If it is, I would contact Apple even if the device is out of warranty. Call the 1-800 number, press 0 repeatedly until you get an operator, and ask to be transferred to Apple customer relations. Explain the situation (a battery that lasted only 9% of its design lifespan), and ask them to make a one-time warranty exception. But don't do that until you've tried an SMC reset followed immediately by booting into Lion (without booting into Mountain Lion first—use the option key at startup to choose the device to boot from).

I guess this is something I should be concerned about, too.

I have a 2011 MBP, and I use wall power almost all of the time. Still, my battery doesn't seem to want to charge above 98%. I figured that was how it is supposed to be, so I didn't worry about it.

Then today, I went to set it up and the indicator light was green on my charger, so I turned it on. The battery was at 97%. This never used to happen with Snow Leopard. If my indicator was green, I was at 100%.

I fear this is a sign of something, and I'm not sure what. After reading these reports though, I have to wonder if Mountain Lion is a battery killer. Not because it drains the battery faster, but I'm wondering if something in the OS can actually wreck the battery. Can it? I mean... is that even possible?

Am I seeing early signs of my battery being zapped?

Same problem here, MBA mid 2011, i5. Fan is noisy, battery down to 2h, the charging area is extremly hot, cannot touch it although CPU temprature is reported as 53 centigrades.

I thought I was losing it. Now I see I'm not the only one with this issue. This is ridiculous!

I've also noticed this. I'm on a MacBook Pro 15-inch Early 2011. Running (obviously) 10.8. Right now, it doesn't even alert me of a low battery anymore.

Astonishing.

Just began a test. Disconnected the power adapter, and the gauge dropped from 99% to 80% in less than 45 minutes.

Essentially making making my mid-2009 17" Macbook Pro unusable for anything more than an estimated 2.5 hours... Not pleased.

I'm seeing a best-case drain of about 20% per hour also.

Apple contacted me and I worked with them to send a bunch of info from my mid-2011 MBA/4G/256G.

They of course didn't promise a fix, but they reached out to me, so I'm satisfied so far.