As far as I know, there are the following differences with the 980:

- stronger motor
- bigger battery
- longer runtime
- automatic carpet detection, which increases the suction power
- slightly louder

Since we don't have many carpets and the battery power is easily enough to clean our 5 1/2 room flat, I opted for the cheaper 960 model. We haven't regretted it for a minute. Theoretically, the battery can also be replaced with the larger model of the 980, so that a longer runtime can also be achieved with the 960.