to charge them I use:
with a 2.5 amp charger to interact with the batterys.
the bicycle was free from the dump,
$60 the bike shop to get a used front wheel, two tires, two tubes.
$730 or so with shipping for the rear wheel motor laced to the rim, 36V motor controler, thumb throttle switch, battery charger, and bag of correct wires and plugs to hook things up, I could have spent less on the throttle switch but I got one with LED battery leavle lights, and I could have spent $50 less on the wheel, but I wanted one with the rear gear cluster, and I got the "Cruser" wheel, so it's the middle speed range of the lower voltage.
So far I've spent $160 on 30 "D" cell batterys, and $36 on copper pipe, and maybe another $15 on misc fittings, wire, and screws, altho I'm not impressed with this battery pack, so I'm going to keep looking at battery options, the D cell batterys can't discharge as fast as the motor asks them, so the voltage tends to drop, and my top speed goes down, the big upside of them is that they are light (15 pounds for a copper and steel rack with 30 batterys inside), and they make the bike look cleaner, but I have a big hill to clime to get home so I want a little more power.
is the compeny that I bought the parts from (they sell compleat bikes too
) they sell parts so you can build a kit to meet your exact needs or compleat kits that you just bolt on to a bike you have, with batterys starting at $400
and going up to $1,049 for a full kit with batterys that can top out at around 37mph
the parts I chose gave me more torque, lower top speed, and a better range