1993 Geo Prizm EV Project

This is my 1993 Geo Prizm electric vehicle. It was originally converted from a new car in 1993 by Drive Electric in Sacramento, California. Drive Electric is no longer in business. This car was included in the premier (and only) issue of ElectricCar magazine.

The original owner put about 1200 miles on the car. It then wound up on a dealer's lot in Corvallis, Oregon with dead batteries. The second owner bought the car from the dealer, installed a pack of 12v Marine/RV batteries, and then put another 1800 miles on it.

I bought the Prizm in July 1998, with 4096 miles on the odometer and a very tired battery pack. I rebuilt the car using a 120v pack of buddy paired Optima batteries, a Zapi controller with regen and a Russco charger. This version of the car had a range of about 26 miles. The Optimas died after 2200 miles, most probably due to my abusing them.

The car is currently being rebuilt again, with a 120v pack of SAFT NiCads and a pair of Brusa chargers. The NiCads and the chargers are used, pulled from a Pivco CityBee that had been part of a Station Car demo project in the San Francisco area. (The entire fleet of 40 City Bees were returned to Oslo, Norway, had the NiCads removed and were then immediately crushed, along with the nice controllers, motors and chargers. Sigh.)

The two front battery boxes hold five SAFT STM 5-100 NiCads against the firewall and three more where the radiator once lived. These NiCads are the air-cooled, low maintenance model. They have a central watering system and only require watering every few or months (at least, that's the claim - I'll know more once the car is on the road again).

The flat plate between the two boxes is the mounting plate for the Zapi controller and liquid cooled heat sink.

To the left of the controller plate is the brush end of the 9" Advanced DC motor.

The space to the right of the controller plate will be used for another mounting plate for two Kilovac contactors, the shunt, the circuit breaker, the throttle pot, the vacuum pump and the 12v aux battery.

The Zapi H2 120 volt, 600 amp controller, with regenerative braking.

Regen doesn't really return that much power to the batteries, but it helps offload the vehicle's brakes and makes the car feel "normal" to me. I don't really like the feel of a car using a non-regen controller when it starts coasting after letting off the pedal. With regen, the car starts slowing down much like an ICE vehicle does. If I do want to coast, I merely leave slight pressure on the pedal and the car coasts like any other EV.

The Zapi's liquid cooled heat sink finished and ready to be installed. Coolant will be pumped into the heat sink through the fitting on the rear, flow through the four length-wise holes, and will exit from the fitting on the left. (Construction details)

Picture of the rear pack and the two Brusa NLG412 chargers. The main charger is used for normal charging, at a rate of 20 amps for the bulk charge and then 5 amps for the finish charge.

This charger also has a "fast" mode which charges the battery pack at a rate of 25 amps for the bulk charge but with no finish charge (intended for opportunity charging). In this mode, the two chargers are used, running at a combined rate of 50 amps, drawing a mere 30 amps from the wall.

The rear battery box fans will draw air from the trunk. The tube coming up between the chargers is a fresh air inlet.

A box will be fitted between the chargers and will contain the AC receptacles for the chargers and the Anderson plugs connecting the chargers to the pack and to the DC/DC convertor.

Closeup of the rear pack showing the bus bars and battery watering connections. The bus bars are tin plated copper. The wires are from one of the two temperature sensors.

This is a closeup of the air inlet holes in the rear battery box. The top set of holes vent from within the trunk, and the bottom set of holes vent from underneath the car. The fans exhaust the air on the other side of the battery box, to the outside of the car. The intent is to help pull some of the charger-warmed air out of the trunk.

Closeup of the Avcon charging port. The Avcon port provides a GFI protected, 240 VAC, 40 amp source. See the Avcon web site for more details.

If anyone ever installs public charging sites in Portland, I'll be ready. Until then I at least have a convient charging plug with a fairly high "coolness" rating. (And yes, the chargers can be unplugged from the Avcon and connected to any 120v or 240v outlet with the proper extension cord, should the need arise.)