i have a similiar setup, Full suspension with Grins all axle but in standard winding, phaserunner and CA. it "was" originally a chinese bafang ultra frame, but after errors and fails with bafang i gave up and ordered the Grin Products, i had to weld a BSA bottom bracket "adapter". The phaserunner is in the place where the bafang motor was.
you could build a triangle battery case and put the phaserunner in there and make all the cables more hidden but it wouldnt be removable.
i have fitted a 154cells battery, 14s11p with 18650ga cells in this triangle. its not removale because i only charge at home or at the camper van and a removable case is more complex.
here is my setup shortly after i finished it months ago and one picture with the bafang ultra motor. i now have front and rear schwalbe johnny watts(great tires) and a front fender. my torque arm is also in the wrong position on this photo, it had to move to the upper part of the swing arm.