Finished my prototype today and did a short test with it. Works fine :-)
It's basically all the same with remmie's, just a few details are different. Used breakout boards sold on endless-sphere for the rectifiers instead of direct soldering to avoid any permanent modification to them apart from the default voltage setting. Arduino code for testing was very simple, but voltage and current regulation works fine.
Test was on my FXS, that's why I just used two rectifiers. Charge Fuse appears to be 60 or 70 A on those models, so less charging power recommended ;-)
Started at about 43% SOC, stopped at around 95%. Needed roughly 45 min, I didn't measure precisely. Current reduction started at about 85% SOC, tappers down quite fast then. No problems at all besides the fact that cell voltage difference is very high during charging, so a balancing with the onboard charger seems to be a good idea from time to time.
Rectifiers made a funny "clicking" and "buzzing" noise under high current, are yours doing the same remmie? Also the yellow warning LED came up from the beginning and shut down when tapering down begann, guess that's a "current limit reached warning" or something like that right?
Things to be done:
-display integration with live coverage of charging data
-buttons for charge current and other adjustments
-230VAC/5VDC supply for Leonardo board and display
-some sort of housing for weather protection
-measurement of input voltage and current for additional features an protection
-enhanced PWM communication to limit charge current to the max. of the chargepoint
-6 piece FlatpackS charger with direct controller connection built into the motorcycle if my dad decides to buy a 13kWh model
Might still take some time to do all of this, need to write a few exams soon
Thanks a lot for the amazing work you have done and to share it with us remmie, wouldn't been able to accomplish this on my own!