Here in the picture we have a photo of two batteries using essentially the same technology, Li-Ion:
As you can probably tell, the other is from a phone – Nokia’s BP-6MT with a capacity of 1050mAh. The other is from a Thinkpad laptop with a capacity of 5020mAh.
So there’s about a 5-fold capacity difference. But look at the size difference! The laptop battery is way, way bigger than five times the phone battery. And the weight difference is pretty dramatic also. In fact, the cellphone battery gets 30mAh/g while the laptop battery manages only 12mAh/g, almost one third of the weight/performance ratio!
It’s basically the same technology so what gives? Why do laptop batteries have such terrible weight-performance ratios?
