Synergy Digital Vacuum Cleaner Battery, Compatible with iRobot Roomba i4 Vacuum Cleaner, (Li-ion, 14.4V, 3400mAh) Ultra High Capacity, Replacement for iRobot 4624864 Battery Specifications: Battery Chemstry: Li-ion Voltage: 14.4V Capacity: 3400mAh Compatible with: iRobot 4624864 Battery Works for: iRobot Roomba i4 Vacuum Cleaner and many more