I suspect that, unlike a computer, the vacuum cleaner has no battery management system so you are expected to manage it yourself:-
- don't use up so much of its stored power that the battery cells damage themselves if their state of charge is too low, and possibly,
- don't leave it charging when it has become fully charged [because the vaccum cleaner might attempt to keep charging the battery despite it being fully charged which will age the cells prematurely].
I have one like that.
It's not as convenient as, say, laptop battery charging but it's not catastrophic.
I suggest you contact the retailer and ask exactly what they mean by "over discharge", what exact state of charge they are referring to and how you will be able to tell if you are reaching that limit.
Denis
