Battery for iRobot Roomba 966, 965, 960, 896, 895, 801, 695, 680,640 and others 14.4 V, Li-Ion: Amazon.de: Home & Kitchen
Roomba model comparison chart (2021) - i3 vs i4 vs e5 vs i6 vs i7 and more - AfterDawn
Cameron Sino 4000mah Battery For Irobot Roomba 614,615,640,652,665,670,671,675,677,680,681,685,690,691,695,696,801,805,850,860 - Digital Batteries - AliExpress