Flip out the 2 side panels (Either sid of the screen ) Under there are 4 screws that hold the screen in place
undo those (Star headed tool req) gently prise the 2 halves apart and you will expose the motherboard
there are 4 starred screws holding this in place the battery is sat behind the motherboard.
be carefull if removing the screen ribbon from the motherboard the clip is quite delicate
you can remove the screws from the board without removing the screen but is a little fiddley
Hope that helps