It depends on how long the device has to run... with or without charging, how much grass it has to cope with, how damp the grass is, how high the grass is, etc. For the first cut of the year, a 6A battery is not enough for our 80 square metre garden. In summer, a 2A battery is sufficient for the final cut.

According to the Bosch easy mower manual the recommended batteries start with 3Amp Hours (F 016 L94 617 (2023.04) O / 22 on page 8).
A 4Ah battery and The Al 1830 charger are the supplied when bought as a set with the mower.I do not know about the other battery.

Is this in response to T free 18 V3 Ah battery as advertised by Bosch?

Super sufficient for a small area

Battery and charger are not included... must be purchased separately.