MacBook Pro 17″ Battery is Huge and Not so Dense in Energy

Ars says the MacBook Pro 17” battery is HUGE.

According to the article, the MacBook Pro 17” has a 95 watt*hour battery that weighs 1.5 lbs. My 9-cell in my ThinkPad X200 weighs 1.12 lb and has 84.2 watt*hours of energy. That means my X200 battery has 75.2 watt*hour of energy per pound and the MBP 17” battery only has 63.3 watt*hour of energy per pound. That’s a little surprising because I would have thought that the super exotic battery from Apple would have higher energy density.

macbook17unibodybattery_ifix

Furthermore, it would seem that the battery life is low for something with such a large battery. Eight hours peak battery life would indicate that the MacBook Pro 17” switched to the lower power NVIDIA 9400M consumes a minimum of 11.88 watts. When switched to the NVIDIA 9600M GT, the MacBook Pro 17” gets 7 hours of peak battery life which means that it is consuming a minimum of 13.57 watts.

Meanwhile, I have actually stretched my ThinkPad X200 12.1” laptop with its 9-cell battery to 11 hours at 7.65 watts on the plane and in theory can get up to 12.87 hours operating on 6.54 watts if I were only reading a long document without generating any load. While the size of the MacBook Pro 17” display might explain some of the extra power consumption, it can’t explain most of it since the ThinkPad T400 14.1” laptop can also get close to 11 hours of peak battery life in stretch mode.

Considering the fact that the same Intel 45nm CPUs are used in the ThinkPads and MacBook Pro, my guess is that Apple’s use of an NVIDIA 9400 as its low-power option may not be the best decision for power efficiency. The ThinkPad T400 is able to get close to 11 hours with a smaller battery by using the standard Intel 4500 integrated graphics adapter in its low power mode while switching to the discrete ATI 3470 GPU. It might have been better for battery life if the MacBook Pro 17” switched between an Intel 4500 and an NVIDIA or ATI GPU.

photo via iFixIt

Related Posts

Advertisement