What kind of glue uses the battery?

Frankly, I'd bring it back to Apple as it's still likely under warranty.

I suspect the glue is a heat type given the speed needed in manufacturing of the system in the first place and what Apple has used before.

You'll need to have a calibrated (Lab type) heat plate that you can place the case on to heat it up to the point the glue is soft enough to pull the battery set free.

The problem here is you first need to remove as many of the plastic parts off first (they are likely to melt or warp from the heat) and once you heat the battery unit up you won't be able to use it again. WARNING: make sure the battery is fully discharged before even doing this!

OK, now you got the old battery free now what? Apple currently doesn't supply the replacement so you can't even get the needed part.

Bottom line here: Just return the system to Apple and let them have the fun even if it costs you ;-}