Not sure where you intend to mount a angled battery but if you attach it to the area in front of the motor mount you can be sure that on a hard landing you will break your frame behind the motor and wipe out your main gear and a servo or two. I tried that and replaced 2 frames (I was using 1500mh batteries).
Put in the fram stiffener for about 16$ before you attach anything to the front of the motor mount area.
Actually a lot easier to just use a 2 toung depressors and zip tie it to the frame to support the battery, nd put some foam tape under the front of them to angle it up so it fits the tapered canopy.