Chosen Solution
I have broken a cable underneath the battery when trying to remove it unfortunately… Is there any way I can replace this or fix this? The iPhone will no longer power on so assume this must be power related? Thanks!
@scott0762 is right, that’s the power button flex cable..to replace it you’ll have to remove battery and logic board, but you can get some help about the howto from the following guide: iPhone 6 Power Button Cable Assembly Replacement
That appears to be the power flex cable, it can be replaced