Just built a 20s 9p pack (72v 27ah samsung 30Q cells). This replaces a multistar lipo pack 20s 30ah (x15 4s 10ah).
Yes there is a 3ah difference but yesterday on the first full drain of the 30Q's my bike went no where near as far and ran out of juice due to a 4-5v voltage sag and hitting about 2.9v per cell. I never saw the lipo pack ever run out of juice and go lower than 3.7 nominal voltage when at rest. I know that the two types of cells discharge comlpetely differently, and i am sure i got around the same mount of sag from lipos but i was very surprised to hit rock bottom before the end of a ride,.. 63v once rested.
Some stats..
22.4ah used
26km /50wh per km
Steep hill muddy off road terrain, stop start riding.
Pulling 85amps peak. (About 9.5amps per cell)
I was able to still ride once on 63v but only at about 40amp.
I spent a lot building the new pack , and was a little disappointed.
Is this to be expected??
Or do i need to lower my coltage cut-off limits? Samsung data says 30q cell is empty at 2.5v equaling 50v on my pack.
Yes there is a 3ah difference but yesterday on the first full drain of the 30Q's my bike went no where near as far and ran out of juice due to a 4-5v voltage sag and hitting about 2.9v per cell. I never saw the lipo pack ever run out of juice and go lower than 3.7 nominal voltage when at rest. I know that the two types of cells discharge comlpetely differently, and i am sure i got around the same mount of sag from lipos but i was very surprised to hit rock bottom before the end of a ride,.. 63v once rested.
Some stats..
22.4ah used
26km /50wh per km
Steep hill muddy off road terrain, stop start riding.
Pulling 85amps peak. (About 9.5amps per cell)
I was able to still ride once on 63v but only at about 40amp.
I spent a lot building the new pack , and was a little disappointed.
Is this to be expected??
Or do i need to lower my coltage cut-off limits? Samsung data says 30q cell is empty at 2.5v equaling 50v on my pack.