3500 mAh battery iRobot Roomba APS 520,530,531,550,555,560,562,563,564,580,581
After 3 years of loyal service, my iRobot 520, was HS; the battery did not want to know anything! After reading reviews, I started and I took this battery: 3500 mAh APS Hannets. After installing and loading 24 hours, impeccable! It is half the price