Apple's 2009 MacBook Pro: Battery Life to Die For
by Anand Lal Shimpi on June 12, 2009 12:00 AM EST- Posted in
- Mac
I was so focused on the iPhone 3GS and Snow Leopard announcements from this year’s WWDC that I almost missed the gravity of the MacBook Pro announcements.
Apple announced price drops on nearly all of its laptops. The new lineup looks like this:
MacBook | MacBook Pro 13-inch | MacBook Pro 15-inch | MacBook Pro 17-inch | |
CPU | Core 2 Duo 2.13GHz | Core 2 Duo 2.26GHz | Core 2 Duo 2.53GHz | Core 2 Duo 2.8GHz |
GPU | NVIDIA GeForce 9400M | NVIDIA GeForce 9400M | NVIDIA GeForce 9400M | NVIDIA GeForce 9400M + 9600M |
Memory | 2GB DDR2 | 2GB DDR3 | 4GB DDR3 | 4GB DDR3 |
HDD | 160GB | 160GB | 250GB | 500GB |
Battery Life | Up to 5 hours | Up to 7 hours | Up to 7 hours | Up to 8 hours |
Price | $999 | $1199 | $1699 | $2499 |
If you want an all aluminum body, you have to buy a MacBook Pro. There’s only a single MacBook model and it’s the white chassis that’s been around for a while now.
Apple added a 13” MacBook Pro to the lineup to fill in the gap, although it’s not clear to me whether this 13” MacBook Pro uses the same LCD panel as the old 13” aluminum MacBook or a derivative of the 15” MacBook Pro’s panel, which is superior.
Of course there are different models within each one of these categories that you can purchase, but they are irrelevant to the discussion we’re about to have. Look at the battery life row in the table above; Apple is claiming up to 7 hours of battery on the new MacBook Pros. The old specs used to be up to 5 hours.
Apple did some clever work on its own here. Standard lithium ion batteries are made up of cylindrical cells, similar to AA batteries. The problem with these batteries is that they waste a lot of space within a notebook (try cramming a lot of cylinders into a box, you end up with wasted space). This wasted space translates into larger batteries than are necessary, which makes for larger notebooks.
In order to continue to drive laptop thinness down, Apple started experimenting with using custom lithium polymer batteries instead of the industry standard lithium ion parts. Lithium polymer cells aren’t made of cylindrical cells (they’re rectangular), so there’s no wasted space. Not only does this make the batteries more compact, but it also gives you greater capacity since you’re using all available chassis volume for the battery.
Makes sense. Courtesy, Apple.
Apple also found that it was wasting space in the removable enclosure for the batteries as well, so its lithium polymer offerings are no longer user removable. I suspect this part of the equation has more to do with cutting costs than saving space though.
Apple first used this lithium polymer battery technology in its MacBook Air. It gave Apple a very thin battery that allowed it to create the MacBook Air’s sweet form factor. Then came the new 17” MacBook Pro, without a removable battery. Apple claimed that this battery would last for five years before it needed replacing and resulted in up to an 8 hour battery life.
The extended life is supposedly due to an on-battery sensor that communicates with the system's management controller that can dynamically sense the needs of each lithium polymer cell and feed that info back to the charging circuitry. The result is slight variations in charging current designed to optimally charge each and every cell; apparently reducing wasted charge cycles significantly. Apple claims that most cells will hit 80% of their life after 200 - 300 charge cycles, but its special lithium polymer batteries will hit the 80% mark after as many as 1000 charge cycles. Apple claims its unique battery chemistry and microprocessor managed charging (Adaptive Charging) is responsible for these gains but it’s a difficult statement to prove; we’ll have to wait and see what happens after a few years of use.
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ltcommanderdata - Friday, June 12, 2009 - link
I guess your findings on MacBook Pro battery life should make those who say Macs are only commodity notebooks with a fruit sticker and a higher price think twice. The 15.4" MacBook Pro may not be the fastest 15.4" notebook or the cheapest, but it offers great battery life and light weight without sacrificing too much performance. That's certainly a combination some people would be willing to pay for.Pirks - Friday, June 12, 2009 - link
[EDITED: Pirks, watch your comments please.]Summary: I'm glad to see someone showing all the Wintel fanboys that Apple is great. Anand showed them GOOD. Thanks Anand! :)))
mesiah - Saturday, June 13, 2009 - link
Wow, I come to this site to get good reviews and avoid 10 year old remarks like that. Please, have mommy take you to the mall to buy more toys and leave this place to the grown ups, its about all we have left.Pirks - Saturday, June 13, 2009 - link
NOT FAIR EDIT!!! Mods, where the heck have you been when chicko was writing expletives about me? Double standard! Wintrolls can swear at me and I can't swear back? Why? Why they CAN and I CAN NOT??!!JarredWalton - Saturday, June 13, 2009 - link
We just got mod ability for the comments section. :-)Pirks - Saturday, June 13, 2009 - link
Does it include comments on DailyTech too?JarredWalton - Saturday, June 13, 2009 - link
Nope... we're technically "sister" sites, so essentially we have nothing to do with what they write about. The editing ability (and post deletion ability) is mostly for when people step way over the line... try and keep the comments more professional rather than less - and remove any outright name calling.just4U - Monday, June 15, 2009 - link
Yep that's why I like reading the comments here. Always quite professional as people leave the Apple/Windows Nvidia/Ati Amd/Intel love hate thingie pretty much alone and are mostly cordial about their biases .. if it's even evident that they have any.PlasmaBomb - Friday, June 12, 2009 - link
Did the 15" model you reviewed the battery life on have the optional 9600gt?I know apple let you disable it, but it being absent may be more energy efficient than being simply disabled.
Also what processors do the MBPs run? As apple simply state 2.53 GHz, when there are several mobile chips which run at that speed - the T9400, P9500, P8700.
Great review.
Thanks :)
sillyfox - Tuesday, September 8, 2009 - link
Yes!Great review! Thanks for kindly sharing.
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