Can I put a 128Gb micro sd card in a Samsung Galaxy s2? I have an untouched Samsung Galaxy S2 just out of its box, though this model of phone is rather old and came out in 2012.

I was wondering could I stick this brand new technology sd card into it?
http://www.sandisk.com/products/memory-cards/microsd/ultra-class10-for-android/
(It says the 128Gb card is microSDXC)
I saw in another post here that v1 and v2 should work in this phone but v3 wont. The site for the sd card doesnt mention any version though.

I want to do this so I can use the phone as a ipod replacement.

Also bonus question.. Anyone know how long one can play mp3s on the samsung galaxy 2 before it runs out of batteries? 

EDIT: I found this which seems promising
https://www.youtube.com/watch?v=yYUg14u_co8
Officially, 128GB Card is supported for the Samsung Galaxy S5 and onwards devices in Samsung releases. But technically, SanDisk’s 128GB card should work in any device that supports the MicroSDXC standard (buy/use at own risk). Check out list of supported devices. You can also verify your device at official SanDisk website here.

What if it shows an error ?

This video should help you change your mind to really go for higher storage space.
https://www.youtube.com/watch?v=JA9fp863d-o

How much of Battery life 

Galaxy S2 has only 1650 mAh Battery, but i think if you just use it as music player then it should claim for more than 1 day battery life. you can also keep it in flight mode to give you less battery drain on networks.