Any battery manufacture will have issues, no one company is perfect. I dont know how many swollen kinetiks ive seen.
And its never installer error, its always the companies who makes the products fault.
From what I can tell, where it is cracked is below the rope handle which is a high stress area for the plastic to support a 46lb battery (possibly why XS went away with this style handle on the other batteriers). But then again I never moved them around by a handle anyways (no matter what style handle), unless your just asking to potentially have a battery drop on your feet