iRobot Roomba Battery for Select 500, 600, and 700 Series
Amazon.com: efluky 3500mAh Ni-MH Replacement Roomba Battery + Replacement Accessory Part Kit for iRobot Roomba 700 Series 700 760 770 780 790 - a Set of 14 : Home & Kitchen
Replacement Battery for Roomba 500 600 700 Series APS Battery 555 595 620 630 650 660 790" - Walmart.com