The gang at iFixit has torn down the iPad mini. You can find the complete teardown at http://macte.ch/0iUEm .
“This product continues Apple’s design pattern of creating devices with built-in consumables that are challenging to replace,” says says Kyle Wiens of iFixit. ” Relative to the $329 price, Apple’s $99 battery replacement program is very expensive. Without regular battery replacements, the iPad Mini is doomed to the same 2-3 year maximum lifespan that the iPad has. Apple has not stated whether the iPad Mini’s battery has the same 1,000 cycles rating as the iPad or the 400 cycle (12-18 month) capacity of the iPhone.”