I have one!
It is antique and made in the Netherlands in the 30, 40 or 50. It is called a bakfiets. Many bikes are nowadays called bakfiets, but this is the real deal.
I drive it with a MP5 on 16 x Headway 40152 15A cells lifepo4 24volt. A so called S8P2 LiFePO4 setup. Sadly the weight slowed my bike a bit down. from 22 km/h to 15 km/h. So I am thinking to upgrade to 32x Headway 40152 S16P2 48 volt / 30A. I can also re-arrange my 16 cells in 1x16 instead of 2x8, but then I loose half my Amps..... SO I am very interested in someone who can tell how many "hard and though" kilometers go out of a 40152 48volt/15A pack. So not the economical tour but the max power discharge curve/experience in KM or something.
Recently I put two Suntech 72 mono-cell, 195 WP panels on the bike as a sort of roof.
It's winter time now and it's totally overcast and grey. How much it will load the battery I do not know, but it charges....... even in these bad conditions with a bit disappointing 0,3 0,4 amps...
Still wondering why SO slow. Each panel can give 6A at 36 volt. To connect the panels to the battery I use a small solar charger, with the correct characteristics. Full, Float, Empty and cutt-off values. I put them at: 28,2v (Full, 3,525volt/cell), 27,8 (Float, 3,475volt/cell ), 23,5 volt (empty 2,937volt/cell ), 23 volt (cut-off 2,875volt/cell). This is in my opinion a very save operational setting.
Do you have plans to build one?
Greetings,
Philip - the Netherlands