Revive a B&D Dust Buster by replacing the NiCd/NiMH battery with 18650 cells
I've charged 4x2000mAh cheap cells externally and just put them into the B&D vacuum for runtime testing.
I've used the vacuum for around 20-25 times for cleaning the cat litter and hair around the apartment.
-> 1 week without charging
I think this is enough, because I don't want to have the charger always on.
For testing purposes, I've tried the vacuum without a battery protection circuit.
The performance was good, but not the best. The battery capacity seems to be enough for ~10-15min, but the cheap "9900mAh" batteries are getting warm after ~30s.
The next try will be with 2x2 batteries (1+1||1+1), so this is the added 2nd battery holder:
I will measure the runtime with 4x2Ah cheap cells and 4x3Ah good cells.
Yesterday I've disassembled the vacuum cleaner and tried to connect the new battery pack.
My first try was a combination of 2 18650 cells in a cheap battery holder with a 10A battery protection board ( https://www.aliexpress.com/item/32920842556.html ).
It was not possible to start the motor, the short circuit protection immediately kicks in and cuts of the power.
20A board. There are 30A boards as well, but only for 3S, which would be too much for the motor (original voltage: 9.6V; 2S: 7.2V; 3S: 10.8V).
with a balancing circuit (~2$).