How can a 12V 80Ah Battery be 1800W? Shouldn't it be 960W? I was looking for 12V 80Ah Deep Cycle Batteries on Amazon and most of them were 1800W. Like this one: https://www.amazon.com/Cycle-Battery-RENOGY-SOLAR-PANELS/dp/B0143K89KA/ref=sr_1_fkmrnull_3
80Ah means "80 ampere*hours" -- approximately, the battery can give 80 amperes * 1 hour, or 160 amperes * 0.5 hours, or 40 amperes * 2 hours.
1800W refers to maximum power -- if you draw more than that, the battery may overheat and fail. At 12 volt, this means 150 amperes. This means that you should not discharge battery faster than that. Incidentally, this means the battery can be safely discharged in about 40 minutes.