These are not automotive batts, they are for battery backup systems/solar power etc. In a car they will get much more abused than they are designed for.
not really. i have had the same one in my trunk for about a year and it still rests at 14.2 and 15.4 at idle //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif
you can buy those big *** tractor batteries anywhere, i have seen them at walmart, tractor supply, battery shops, advances, autozone, napa, etc. There is a reason nobody runs them and thats because they dont want to breathe the gasses and have acid sloshing around on their trunk floor