“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,” Anand Lal Shimpi reports for AnandTech. “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,” Lal Shimpi reports.
“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,” Lal Shimpi reports.
“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,” Lal Shimpi reports.
After conducting benchmarks (see full review), Lal Shimpi reports, “Apple’s 7 hour claim is well within reason. For light workloads, even on WiFi, you can easily expect 6.5 – 8 hours out of the new 15-inch MBP. As I write this article on that very system I’m told that I have nearly 8.5 hours left on my charge. If you do a lot of writing on your notebook, the new MBP is exactly what you’ll want; it will easily last you on a cross-country flight if you need to get work done… It looks like, once again, other notebook makers will have to play catch up to Apple in this department.”
“There’s no other way to say this. If you care about battery life and portability at all, buy the new MacBook Pro…. While I only tested the 15” model, I’m guessing the 13” model should leave a similar lasting impression,” Lal Shimpi reports. “Today I am more than comfortable saying that this is the best Apple notebook I’ve ever laid my hands on. The build quality is excellent, the base specs are solid and of course, the battery life.”
Full, very comprehensive, review – highly recommended – here.