The website states up to 3 hours battery life. This was one of the reasons I was drawn to the device.

I have been testing it our all day today and there are a few things I noticed:

1) when the device starts at 100% charge it lasts for about one hour.

2) during the cleaning cycle, once the device reaches 20% charge it returns to the charging station and recharges but only to 80% before it continues the cleaning cycle. 

3) on the subsequent parts of the cleaning cycle the device only lasts ~40-45 minutes depending if it does mostly hardwood or carpet

Below is the layout and roughly the paths it took. Basically it covered the outside perimeters of each room but most of them not the center or under tables and chairs. Also during the run it covered the same areas at least 2 or 3 times. The whole area is ~140m2 and with the 2 runs according to the app it covered 65m2