We expected the Surface RT and the Pro to share similar internals and disassembly procedures, but it turns out that the Pro is a completely different bag of beans. The display assembly is anchored down with the most adhesive we’ve ever seen on a small device; in fact, it took us well over an hour to figure out how to get inside — an iFixit first. The Surface Pro has some nifty features, like a removable SSD, but that upgradability is marred by non-accessibility to the internals. Adding salt to the wounds, the battery is buried behind the motherboard and glued down to the case. Because of this, the Surface Pro received a 1 out of 10 score on our repairability scale — the worst any tablet has ever received.
Notably, the Surface Pro features the 'Cadillac' of batteries from LG rated at 42 Wh, 7.4V, and 5676 mAh. The iPad 4 has a 43 Wh battery at 3.7V. Despite all the battery juice the Surface Pro runs for less than 5 hours.
Take a look at the full tear down using the link below...