Ez Go Marathon 2 stroke problems

[JBowler4]

I've been on my 3rd 350 amp cranking amp husky lawn mower battery within a year. Could it be possible that I have something that could be burning these batteries up? Or maybe just from bouncing around? But my question is should I spend the money and buy a deep cycle battery or small car battery? Or could there be a problem somewhere that is causing these batteries to fail I noticed today that when I would try to get the motor to crank (which it won't even turn the motor over) the positive battery cable was getting hot I checked all the grounds they look good. It's not that it kills battery to fast but it just burns the battery up when I test the battery on my charger it says bad battery I go and get a new battery and it works fine any thoughts ????

[1989Marathon]

Measure the voltage at the battery when revving the motor. It could be a bad voltage regulator, allowing the battery to over-charge.