Under  hoodMain bank dont let the water get too lowbattery heater install
OwnerJay Gross
LocationPhoenixville, Pennsylvania United States map
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Vehicle1981 Volkswagen Rabbit
South Coast Technologies conversion from VW factory in 1981
MotorSiemens 1GV1 Shunt Wound DC
heavy fork lift motor max power 45 HP @130V and 320 amps. 23 HP as installed originally. Max current is 250 Amps. Typical current 175 Amps at level 55mph.
Drivetrainstandard VW transmission. Uses Clutch. Special inner CV joint boots to clear Motor
Controller custom design by SCT
Controls field voltage by pulse width modulation only. Higher field voltage for lower speed (saturates field) Max field current is 10 amps. Modified for higher output current.
Batteries20 Deka eighteen GC-15 + two GC25G in front , 6.00 Volt, Lead-Acid, Flooded
I permanently added 2 more main batteries in front on shelf behind radiator. I sometimes added another set of sealed batteries behind the front seat which resulted in a very fast idle speed. I was able to get idle speed down by adding small sealed 14AH battery in series for motors field only. I used these just for extended range trips. (The extra range batteries are from my electric tractor and had to be charged separately.)

Batteries are 7 years old and were tested at 75% capacity last year. Not used much, not over charged. Also use desulfators. Let water level get too low (trying out new charger and one exploded!) Removing all batteries now...
System Voltage108 Volts
Original died long ago. It was too heavy anyways. Now charging separate banks with solar panels in 48v and 12v banks using solar charge controllers. Solar charge controllers and panels are not grounded, so nothing shorts out. Takes 2-3 days of sun for normal charge. I also have manual chargers (transformers) which also goes through Solar charge controllers.
HeaterConair hair dryer works on 90-132 volts DC fine but is really noisy.

Tried original VW heater core, 1200W water heater element in iron water pipe and 12 volt water pump. It did not work at all!

Originally equipt with diesel BOSH heater which is sitting in my garage in a box because it smells. It has lots of heat!
DC/DC Converter STC custom design
Stock converter did not not enough current, so using 2. I also have DC discharge problems so I disconnect the small aux. battery when not using car. Sealed 21 AH aux. battery is mounted under seat inside.
InstrumentationStock STC battery gauge worthless. I just know routes taken from house and if I can make it or not based on battery resting voltage when I get home.
Top Speed65 MPH (104 KPH)
120 volts helps a lot as did the high pressure tires and an front end alignment.
AccelerationOK, not too bad on hills for an electric... Faster than my old VW Bus!
Range12 Miles (19 Kilometers)
weak batteries and old technology. Also a lot of hills in all directions from house! Heating batteries to 90 degrees in the fall helps range maybe 10%
Previous owner said he got 25 miles if level with some highway driving. (new batteries @ 108V)
Watt Hours/Mile385 Wh/Mile
150 amps at 50 mph around 110 volts
180 amps for 55 mph level around 100 v
275 max draw going up hills around 90 volts
battery temp around 75 degrees
EV Miles
Start:45,000 Miles (72,405 Kilometers)
Current:47,000 Miles (75,623 Kilometers)
Total:2,000 Miles (3,218 Kilometers)
    As of 8/31/2009
Seating Capacity2, back of car SCT modified for large battery tray holding 18 golf cart batteries.
Curb Weight3,100 Pounds (1,409 Kilograms)
Tireshigh pressure (52psi) Sumitomo HTR200 175HR13. Worth every penny in terms of extra range and corning ability. Way cheaper ($40 each) then adding more batteries.
Additional FeaturesPlayed around with battery heaters a lot. You can get extra range even in mild weather like 70 degrees by heating the batteries to around 85-90 degrees. Make the heater powerful enough that you can heat the batteries up just before your trip. Batteries need to be warm at some point in charging too for best results. The charging process adds some heat too. 750 watts of rain gutter deicer cord (or tape) run back and forth under batteries and over foam works good for 1000 pounds of batteries.

I also used several heavy aluminum foil layers with foam under the heater cord to reflect the radiant heat. This is not good for flooded batteries as excess spillage will short out the battery string! 7 battery heater blankets were not even close to powerful enough. Do the calculations for specific heat found on the internet. 345 Kg of lead, 169Kg of water for 18 rear bateries. 60 degrees F to 80 degrees F is 12 degrees K. The electrolyte level makes a significant difference in the total energy(1.84Kw-Hrs) and time needed to heat them up.
48 Volt battery banks can be plugged into rack mounted computer UPSes to provide backup power to run the house. 48V of electric tractor batteries are used to heat up the car batteries prior to trips. All of this is solar powered mostly.

code by jerry