Batteries and miniBMS installedUnder the hoodnew colors of doorpanels and consoleview of backseatFront battery boxBox for accessory itemsCells behind backseatLed lights
OwnerMikko Turunen
LocationCentral Finland Finland map
Web/EmailWebPage email image
Vehicle1989 Volkswagen Golf mk II
Cheap and common, fits my bill nicely. Got it
very soon after it got inspected as an ICE
vehicle for a last time. New front shocks and
rear brake lines at that time.
MotorKostov 9 inch 220V Series Wound DC
Prototype version. Only had been run in test
bench. Fields configurable for series/paraller
operation. This one runs in paraller mode only
(for more RPM at this voltage level)
Drivetrain4-slot (+reverse) manual gearbox. Originally 1.6
engine with over 300 000 kms (~ 187k miles). Ran
fine. Gearbox support cushions were gone.
ControllerOpen ReVolt rev. 2C (144V/500A)
max. 144V/500A, passive air cooling. Lots of
configurable parameters and serial data
communication for logging & setting parameters.
HE throttle modification done later.
Batteries45 Thunder Sky LFP90Ah, 3.20 Volt, Lithium Iron Phosphate
Cells were in really bad shape when I got
them. All of them read less than 0.1V per
cell, but 23 recovered simply by charging.
Still I abandoned one of those 23 recovered
and added 8 new cells to get 30 cell
configuration. Later I ordered even more to
get 144V system.
System Voltage144 Volts
Charger TC Charger 1,5kW PFC
Same as ElCon but bought directly from Chinese
Heater4x 1500W ceramic heater elements (rated 1500W at
120V). Serious and instant heat even if it is
-22F (-30C) outside. 2x SSR relays to control
full/half heat power.
DC/DC Converter TC Charger 400W, isolated
From same company as charger. Input isolated
from output, 13,8V floating charge voltage.
InstrumentationStock speedometer, aftermarket tacho and Cougar
LCD (motor & battery amps, pack & accessory
voltage, SOC, different temperatures).
Top Speed77 MPH (123 KPH)
It just didn't go faster on flat road. 400 motor
amps and 270 battery amps limits were used at
that the time.
Acceleration96V figures:

0-30 mph (50 kph) ~6 sec.
0-50 mph (80 kph) ~16 sec.
50-60 mph (100 kph) some patience
Range45 Miles (72 Kilometers)
Mixed driving range. DOD >90%.
Watt Hours/Mile125 Wh/Mile
115A/96V at 80 kph (50 mph)
175A/90V at 100 kph (63 mph)

~80A/140V at 80 kph
~120A/135V at 100 kph
EV Miles
Start:226,800 Miles (364,921 Kilometers)
Current:234,941 Miles (378,020 Kilometers)
Total:8,141 Miles (13,098 Kilometers)
Seating Capacity5 adults
Curb Weight2,100 Pounds (954 Kilograms)
96V system: Gained 75 kg after everything done
(about +165 lbs). Still has load capacity of
450 kgs (990 lbs).

144V system: added 50kg of batteries and some
more kgs of steel framing. Still enough load
capacity for 4 normal sized adults.
TiresNokian Hakka Green (175/65/13) on some old
aluminium rims.
Conversion TimeAbout one full year from buying donor car to
passing inspection. All the work done in about
30 weekends. Didn't have much time in hand.
Conversion CostAbout 7500e (9500$). Was ~8300$ before voltage
upgrade. Including everything. Almost every nut and bolt too.
Additional FeaturesAll the interior lights are replaced with leds including
dashboard/gauge illumination.

Footwell lighting also added for both sides.
Road legal conversion. Passed inspection on 9th march 2011. Been
driving daily since.

Boring city driving video available at
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Lots of pictures at:
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June 20th, 2011: updated Wh/mile figures after installing Cougar
LCD instrumentation mainly for pack voltage display. It also
drives stock fuel gauge which displays SOC. Other info included in
LCD: motor/battery/controller temperatures, motor/battery amps,
accessory voltage, SOC in percentage, kilometers-to-empty.
Planning installing batteries in different order to gain more
cargo space.

August 8th, 2011: added a video link and two pictures. Car is
getting front battery rack as it feels a bit heavy at back. Front
box will house 20 cells and new box at the back will house another
25 cells. Yes, voltage is going up too. New charger and proper
fuses are on order. More miniBMS boards and new wiring are also
needed (orange & double insulated to pass inspection for voltages
over 120V).

September 7th, 2012: voltage upgrade done. Actually it was done
during January and inspection passed right at the first try. Major
heater output improvement. 96V DC/DC blew the first time it
received 144V, bought same kind of unit but made for 144V.
Replaced aux battery with 4x 90Ah old TS cells. Reduced max motor
amps to 400 due excessive clutch slip at 500A. Replaced worn CV
joints. Added aftermarket tachometer and led parking lights to the
front. Bought new LRR tires but didn't notice any improvement in
efficiency. Tested top speed capability and got 77 mph. It doesn't
go any faster at these settings. 2nd gear takes me to 37 mph (60
km/h), after that 3rd gear works up to 60mph. Torque stays up
until 4000-5000rpm. I like it. I'd like to add even more voltage
to get everything out of this motor (220V+) but then again I
should upgrade every power component.

spring 2015: Framing under the car got too rusty and I got tired
of sheet metal welding. Ripped all the electronics away and called
local scrapyard to have them pick up the rotten body. Most of the
batteries went into a riding lawnmower conversion and rest have
been used as trolling motor battery and whatever I could imagine.
Very handy and powerful batteries. Some old cells gave up during
the winter. I've been thinking mk3 conversion since. I'll
definitely do it one day.

code by jerry