My son helping me to remove the ICE
OwnerRuss Sciville
LocationLeicester, England United Kingdom map
Email email image
Vehicle1998 Lotus Elise S1
Probably the best and lightest sports
car on the road.
Only 118bhp from the ICE produces 0-60
in 5 seconds.
MotorSiemens Ford Ranger/Siemens 5133WS20 3-Phase AC
For cost reasons I am using one of the
ex Ford Ranger motors which I have
modified for non oil lubricated use.
DrivetrainSiemens 5133WS20 motor directly connected
to the existing gearbox/differential fixed
in third gear.
ControllerSiemens Simovert 6SV
I was lucky to purchase a used Simovert
from the ever helpful Evisol whom I
would recommend to anyone unreservedly.







Batteries94 Hi-Power LiFePo4, 3.20 Volt, Lithium-Ion
The cells are 50Ah in a rugged plastic
shell.
Unlike Thunder Sky cells, these do not
require clamping together to stop them
expanding, which helped when installing
them.
They only have 6mm threads in the
contact studs which are rather puny.
They came with a bag of aluminium
screws which were ditched for stainless
steel hex bolts for a better and
tighter connection.
The link bars appear to be very thin
but carry the current (100A max.)
without warming much.






System Voltage320 Volts
ChargerBrusa NLG513-Sx
The Brusa is an excellent software
configurable charger and very compact.
It also uses CAN networking which I
propose to use with BMS when I
get around to it..
HeaterCeramic electric when I get around to
it.
I am pleased I changed my original idea
of using the coolant heat to pre-heat
the heater air as it simplifies
pipework in the rear of the car and
tests have found that there is very
little heat generated unless heavily
thrashed.
I used the heater matrix as a radiator
and sat it behind the RH side air vent.
No fan is fitted yet as I cannot see a
use for it.
If you get stuck in traffic, an EV
cooling system cools down, the opposite
of an ICE car.
DC/DC ConverterSiemens , part of the Simovert inverter
InstrumentationLotus at the moment. The inverter has a
compatible tacho pulse output which
works perfectly with the Lotus "Stack"
instrumentation which is scaled up to
8,000 rpm. The speedo has a pickup on
the rear wheel hub so that still works.
Top Speed85 MPH (136 KPH)
I am using third gear only which seems
to be dead on.
1st gear has uncontrollable wheelspin.
My top speed is only limited by the
100A limit I have given the inverter to
keep the batteries to 2C for longevity.
This limits the motor to 25Kw although
it is capable of short term 67Kw.
85 mph is at 6,000 so there is plenty
left.
AccelerationI haven't timed it yet but when the
battery current is limited to 100A (2C)
and in third gear, I get about 12
seconds 0-60mph.
Because the acceleration is so linear,
the speed is deceptive and you pull
away from most traffic after a couple
of seconds.
Range60 Miles (96 Kilometers)
I have only taken the car on a 40 mile
run before charging as I have limited
the charge on the batteries to avoid
overcharging individual cells until
battery balancing is installed.
My 40 mile drive was a thrash though on
country roads at silly speeds as a
proving trial.
At no time did the battery voltage drop
below 280v on a 100A peak draw.

I am hopefully expecting more with
sedate driving.



Watt Hours/Mile200 Wh/Mile
I haven't used the calculator yet but I
use a second hand house electric meter
from Ebay to note the power used to re-
charge and I am amazed with the
results.
On a drive to work of 13 miles I need
about 2 - 3 KWh (two - three units) to
re-charge the batteries.
Some of this is at silly speeds through
the country.
Why have we waited so long for electric
cars?
EV Miles
Start:48,200 Miles (77,553 Kilometers)
Current:49,400 Miles (79,484 Kilometers)
Total:1,200 Miles (1,930 Kilometers)
Seating CapacityJust two slim lithe people
(surprisingly like myself!)
Curb Weight1,800 Pounds (818 Kilograms)
The Lotus is approx. 800Kg in standard
form.
I would expect it to be about 950Kg in
EV form.
The only changes I have made is to fit
stronger springs at the rear to offset
the battery weight.
TiresOriginal
Conversion TimeStarted in October 2007, it is now
June 2009 and it is all finished
and working but for completion of the
batteries BMS.

Using third or fourth it flies up and
down my drive at crazy speeds! 1st gear
just wheel spins.
Conversion CostLots but less than it could have been.
£7000 for the 1998 Elise
£700 for the motor (then $2 to the £1
!!!)
£5,500 for the LiFePo4 Hi-Power
batteries.
£2000 for the used Simovert inverter
£2000 for the Brusa charger.

Overall, not cheap but great fun.
It was scary ripping out the engine and
associated electronics, but surprising
how it all unplugged and left the rest
of the circuitry in place.
Additional FeaturesI used the original gearbox for now but not the
clutch as clutches are for ICE's.

I am staggered how many people discuss using auto
transmissions with electric motors on forums as they are
so inefficient and simply not required.

The Lotus for various reasons lends itself well to EV
conversion.

It is surprising how many areas there are for batteries,
in the fuel tank low in the centre, in the front where
the Pb battery and heater matrix was, and in the rear.

Being able to use the original instrumentation gives it
the professional touch.




I now have the car fully legal with insurance, MOT test
and it has been re-licensed as an EV.
This gives me free road tax (£400 on my M3) and of course
no servicing bills (my M3 is silly money!!!).

Just need to add some appropriate stickers to show other
road users how last century they are.

See this actual car when new on the front cover of the
book "ELISE. REBIRTH OF THE TRUE LOTUS" by Alistair
Clements.
A brilliant book charting the development of the Elise
from concept to reality.

code by jerry