Step 6: Batteries
This car uses 6 x 12V batteries, for a 72V system.
These are Deka Dominator true Gel-Cell batteries. They can not leak or spill acid, nor do they require watering.
I was fortunate enough to be able to get these batteries, slightly used, for $12 each - essentially scrap metal prices!
One downside of these batteries is that they are picky about charging voltage. I was finally able to find a 72V charger designed for these batteries, and got it used for $200.
If I had used the more typical deep-cycle flooded batteries, I could have used a different charger, or even 6 12V chargers, one on each battery.
Four batteries are in the cargo compartment of the car, and two are in front, where the radiator used to be.
For the rear batteries, I cut two pieces of bed frame to lay across the spare tire well, and ran a bolt through the end of each piece down into the frame of the car.
For the front batteries, a few friends came over and helped me weld in a metal tray for the two batteries to sit on. Then I cut two short pieces of unistrut, and ran threaded rod through holes in the tray to bolt the batteries down. I then insulated the front batteries with rigid styrofoam and re-installed the front bumper.
I went to the boat store and bought a "battery charger power inlet". This is a male electrical connection with a rubber cover. Since the gas tank was already removed, I installed the power inlet where the gasoline used to go in.
I added an additional circuit in my garage, just for the car, and have a 25' 12 gauge yellow extension cord with power indicator light in the end, just for plugging the car in with.
Plug it in at night, and it's charged the next morning, automatically.
Update! I later played around with more batteries. With a motor controller that supports higher voltage, I was able to run up to 144V (12x 12V batteries.) At that voltage, the top speed of the car was at least 73 mph, but I really had no cargo space.
Just so you know, Ford Ranger front coil springs fit the back of a Geo Metro, but you have to shorten them.