How long does a 2200a h batery last?

The duration a 2200 Ah battery lasts depends on the load it's powering. For example, if the battery is discharging at a rate of 2200 amps, it would last for one hour. Conversely, if the load is lower, say 220 amps, the battery could last for 10 hours. To determine the exact duration, divide the battery capacity by the current draw in amps.