Take a look at the back of most Ultrabooks and you’ll find nothing. By having sealed-in batteries the OEMS save money, weight and space. The owner, however, is left with the big unknown of battery lifetime and if you’ve ever owned a laptop you’ll know how totally useless they are when you have to drag the mains cable around with you everywhere. I recently had to order a new internal battery for a Samsung Series 5 NP530 that is under two years old and has zero battery capacity. On the other hand I’m typing this on a two-year old Ultrabook that still has 85% battery capacity. So how long will the average battery last?