Well, you try to connect that batt to the motor without a speed controller- like just a relay or knife switch- and you're gonna have hell to pay. The starting torque of a DC motor on a big batt is enormous. It can easily break traction, skid, and generally hurt you and be dangerous.
You need a gel cell/AGM batt. There's actually quite a lot of difference in them, and you have specific needs. Unfortunately mfgs are rarely forthcoming in the strengths and weaknesses of their design.
The one I DO know about is BB Battery's EB series (Electric Bike), because one of their engineers took the time to explain everything in proper electrical terms that I have confidence in. Their EVP series for example has super-high current capabilities but wears down sooner over many deep cycles- including the high current capabilities. You'd only need current this high for racing anyways. The EB was designed to deliver high currents (though less than the EVP) over as many cycles as possible in high temp/vibration environments.
Digikey carries the best price on EB batts. I went to some work getting them to carry the EB20-12 as a "stocked" item because the Robomower community desperately needed a battery that wasn't going to crap out in a season. Actually, right there, 2x or probably 4x of these will do it for you. But, it WILL be expensive. However, be aware that other batteries costing half as much will probably not give you anywhere near half the total runtime hours, nor the range-per-charge, making them a less economical option unless you want to just run this a few hours and take it apart again.