Fast prototyping ;-)Case studyThe batteries arrived!Testing batteriesCooling gridContacted cellsfinished battery packscontroller mounting
LocationLucerne, Lucerne Switzerland map
Web/Email email image
Vehicle1981 Yamaha RS 125 DX
MotorGolden Motors HPM-10KW fan cooled Brushless DC
. Initially I struggled to get a certificate for the continuous power measurements for the road registration procedure. But the Swiss registration officer assured me, that they won't request this, as long as the declaration on the motor looks trustworthy.
DrivetrainChain Drive
ControllerKelly KLS7250D, 24V-72V, 400A
Batteries72.00 Volt, Lithium-Polymer
New technology Graphene Lithium Ion Polymer cells from Shenzhen WESTART Technology Co. Ltd. 40 cells, 3.6V, 20Ah, continuous discharge 10C, totally 2.88kWh, water cooled.
I use them in 2p20s configuration, separated in 5 boxes, water tight and water cooling ability.
System Voltage72 Volts
DC/DC Converter
I will change the original board Voltage of 6V to 12V
Top SpeedTarget: 62 MPH (100 KPH) or up to 75 MPH (120 KPH)
AccelerationShould be decent. I'm curious to see!
RangeTarget: 31 Miles (50 Kilometers) or more
EV Miles
Start:20,533 Miles (33,037 Kilometers)
Current:20,533 Miles (33,037 Kilometers)
Total:0 Miles (0 Kilometers)
Seating Capacity2 adults
Curb Weight0
280 lbs (127 kg), estimated, including batteries
Conversion TimeI started the Project in November 2015. Still working on it...
The project is still going on. It's given me a lot of fun and a lot to learn.
Figuring out how to pack the batteries into that little space took a lot of time. Right now I'm mounting everything onto the bike.
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code by jerry