My son helping me to remove the ICEOn the road
OwnerRuss Sciville
LocationLeicester, England United Kingdom map
Web/EmailWebPage 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
Ebay sourced ex Ford Ranger motors
which I have modified for non oil
lubricated use.

I have sourced another three motors for
future projects and would be interested
in the gearbox for a Ford Ranger EV if
anyone has one available.
DrivetrainSiemens 5133WS20 motor directly connected
to the existing gearbox/differential fixed
in third gear.
Controller SD100
I am now using a Scott SD100 inverter from New
Zealand. Brilliant controller at a great
price. Most major manufacturers wouldn't sell
to me so their loss, Scotts gain.
Used to use a Siemens 6SV that Siemens used to
sell to OEM's in the 1990's in the early days
of EV's.
Batteries95 Originally Hi-Power LiFePo4, now Wina batteries, 3.20 Volt, Lithium Iron Phosphate
The cells are 50Ah in a rugged plastic
Most are in the rear with 30 squeezed in to the
old fuel tank low down behind the seats.
System Voltage320 Volts
ChargerBrusa 3.7kW
Used to use a 2kW Elcon but moved to a NGL 513
from Brusa linked to an Orion BMS.

HeaterCeramic electric element from a 1800
watt room heater I purchased from Ebay.
This is only 100mm x 100mm x 15mm wide
and has a 120mm computer type fan mated
to it. It seems quite happy with the
300v pack supply and doesn't overheat.
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
I used the original heater matrix as a
radiator and sat it behind the RH side
air vent.

The cooling fan only starts running
after much abuse has been handed out in
summer conditions.
DC/DC Converter DCDC206-454
1kW DC-DC converter sourced from who look to have quite a decent
range of products for EV converters.
InstrumentationLotus "Stack". 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 Speed90 MPH (144 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
200A limit I have given the inverter to
keep the batteries to 3C for longevity.
This limits the motor to 30Kw although
it is capable of short term 67Kw with
larger cells.
90 mph is at 6,000rpm so there is
plenty left as the motor tops out at
AccelerationI haven't timed it yet but when the
battery current is limited to 100A (2C)
and in third gear, I get about 10 - 12
seconds 0-60mph.
When I increased the current limit to
140A it is much quicker and now serious
fun and I can keep up with hot hatches
on country roads.
Well worth the possible reduced cell
Remember, this is using third gear
only. I haven't tried 1st or 2nd gear
for performance tests due to the
stresses on the transmission.
Because the acceleration is so linear,
the speed is deceptive and you pull
away silently from virtually all
traffic after a couple of seconds.
Only a noisy clutch slipping start from
an ICE can beat me.
Range60 Miles (96 Kilometers)
My furthest trips have been a couple of
55 mile runs to the South of Stratford
Upon Avon and also to Newark, about the
same distance North.
The cell voltage was beginning to dip
at the end, but I feel it had a fair
bit left.

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
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
EV Miles
Start:48,200 Miles (77,553 Kilometers)
Current:70,000 Miles (112,630 Kilometers)
Total:21,800 Miles (35,076 Kilometers)
Seating CapacityJust two slim lithe people
(surprisingly like myself!)
Curb Weight1,800 Pounds (818 Kilograms)
The Lotus is approx. 800Kg in standard
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.
TiresToyo Proxes T1-R running at 35psi
Conversion TimeStarted in October 2007 and it was initially
completed in 2008 with various changes and mods
over the years to improve it.
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. (Less than £1500 in 2021)
£2000 for the used Simovert inverter
Around £4500 for the Scott SD100 inverter.
£2000 for the Brusa charger (£450 for
a Chinese Elcon (Tiechen) charger).
£1200 for the Chinese BMS system with colour
touch screen, now superceded by an Orion BMS
costing the same.

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 car electrics in operation.
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
I fitted a spring recoil cable drum with
15 metres of
cable for charging, in the exhaust
silencer space.
This allows plenty of cable to reach
friendly pub
For speed, I have also fitted a Type2
socket where the filler cap is as it is
easier to access
for home charging.

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 a
professional touch.
The car is fully legal with insurance, MOT
and it has been re-licensed as an EV.
This gives me free road tax (£245 or more
on my BMW M3) and of course no servicing bills (my M3 was
silly money!!!). Now driving a Model 3 Tesla as the daily car.

I have now added 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
A brilliant book charting the development
of the Elise
from concept to reality.

Next Project.

I have found an excellent design of kit
car (www.vortex- and the designer/manufacturer
(Chris) has
designed in the electric car requirements
from the
chassis upwards.
It has more than twice the Elise's power
and range
(100 x 100Ah CALB cells).

I had a sponsored BMS from "Frazer-Nash"
but the support was
dreadful and I never got it working.
Was offered an inverter from a US company
on trial but that
offer seems to have dried up for the

The Vortex is now using an Orion BMS from
the US which is
excellent. Does everything I could wish
for and more.

Any sponsorship offers would be gratefully
accepted and would
receive good advertising for the company
involved as my cars
are often displayed at shows and have
competed in the "Future
Car Challenge" Brighton to London event
for EV's three times
now and won best private entry twice as
well as one for the
lowest energy use for a sports car.

code by jerry