Amazon.com: 14.4V 3200mAh i7 Battery Replacement for iRobot Roomba e and i Series, Large Capacity Battery Compatible with Roomba i7 i7+ i8 i6 i4 i4+ i3 i3+ i7158 J7 7150 7550 and
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
Amazon.com: Battery Replacement Compatible for IROBOT Roomba 614, Roomba 615, Roomba 640, Roomba 652, : Home & Kitchen