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Super Noob Questions

1039 Views 0 Replies 1 Participant Last post by  22350
hello everyone.

I have owned electric cars for about 6 years now.

I have also been involved in customizing motor scooters for about 30 years. Including very high power engines.

Anyway, I was building a Lambretta, with a 39hp piaggio engine, but lost my passion for it. I am more and more only interested in electric drive. So I scrapped that project. That project is here, if you want to see what was happening:


I am redoing an electric drive version of this project. I have sourced this motor, which the manufacturer has agreed to modify:


As this is open and won't work in a hub that way, they will put it in a sealed case and convert it to water cooled. Before everyone loads on about hub motors not being optimal, I know. I just don't have any room for a swing arm mounted drive. Wish I did. That said, this motor is only 15 pounds. Maybe 18 with mods.

My problems are in understanding the configuration of the batteries. I need about 16kwh to have any sort of range on this thing.

Looking at the specifications of the 2018 Nissan leaf battery. Seems the only battery that has enough energy density to fit in the frame.


Each of their modules has two sub-modules rated at 7.3v & 112.6ah.

Basically 20 sub-modules at 7.3v and 112.6ah

Currently the motor is running 48v. They are, however, modifying the motor to be sealed with liquid cooling. They are also modifying the maximum rpm to 2000rpm limit.

My question is related to the configuration of the batteries into the correct voltage. And, if that voltage should be something else, for maximum efficiency, what would be the best voltage? I might be able to modify the motor's voltage, if there is any advantage to doing that with a 2000rmp motor.

I understand that the battery ratings are for optimal voltage, but I guess what confuses me is that the configurations to get to 48v.

If I were to put seven of these "sub-modules" (7.3v 112.6ah) in series, you get 51.1v.

If that voltage is good to run 48v, I would have to sister 7 additional sub-modules. That would basically I am running 7 complete double modules, as pictured on the spec site. Now I have 3 remaining double modules. I would assume that I just put those in parallel?

Feel free to beat the hell out of me for my ignorance.