"Everyone asks for battery life," said Panos Panay, Microsoft's head of Surface devices. "It actually doesn't matter what device you're using."
The upgrade was also in response to demands from gamers and engineers who wanted better graphics. The new Surface Book's GPU isn't quite top-of-the-line, though: it's a GeForce GTX 965M, instead of one of Nvidia's new 10-series chips.
Microsoft Surface Book i7 brings powerful performance to 2-in-1 design (pictures)
Microsoft introduced its first Surface Book in October 2015. It featured PixelSense technology and "best-in-class" palm detection. With 128GB of storage and up to 16GB of memory, Wednesday's upgrades mean the tablet-laptop hybrid will be even faster.
The Surface Book i7 has a 30 percent battery life jump from 2015's model, which boasted 12 hours of juice.
The Surface Book, Microsoft's high-end answer to Apple's MacBook Pro, started at $1,499. But its high-powered update jumps the price to $2,399.