Wow...that is a lot of options. Let's say instead of the gas powered tow vehicle charging the 12-48VDC battery bank you have a small generator (maybe one not big enough to handle the full load of charging). Do you have an idea of required size of the battery bank balanced with a generator for rapid charging? For example, with a small 2000 watt gen you'd need X number of 100 Ahr 12V batteries.
That’s easy enough to figure out. We need about 120% of the 5.8kWh battery to offset charger inefficiencies (about 85%).
So, one full charge of the bike requires:
7kWh = 120% * 5.8kWh
Then, we need to know how long the 2000w generator will be running (the Honda 2000w generator in the North American market puts out about 1.4kW continuous @ 120V * 13A):
7kWh = 5 hours * 1.4kW
Now, let’s add in the 12-48 volt charger inefficiency of 85%:
8.4kWh = (1 / 85%) * 7kWh
Now, let’s calculate the actual 2000w generator run time to replace the 5.8kWh in the Alta bike:
6 hours = (8.4kWh) / (1.4kW generator output)
I’d probably want enough 12 volt batteries to do at least one full charge, and then let the generator run all afternoon charging them back up:
700 amp/hours = 8.4kWh required / 12 volts
So, about 7 deep cycle 12 volt batteries at 100a/h minimum.
NOTE: I didn’t calculate inverter losses from the batteries to the Alta “fast charger”... need slightly more batteries.
