My son helping me to remove the ICEOn the road
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
Ebay sourced ex Ford Ranger motors
which I have modified for non oil
lubricated use.

I was able to source another three of
these motors from the US to use on my
next projects so thanks guys.
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 who helped
me greatly during this project.
Due to a lack of cost effective EV
inverters, I am working on modifying an
industry standard inverter for my next
project.
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 (140A max.)
without noticeably warming.
System Voltage320 Volts
ChargerBrusa NLG513-Sx
The Brusa is an excellent software
configurable charger and very compact
although very expensive.
I have recently sourced a much cheaper
charger from China which communicates
with my BMS via CAN network.
It works as well as the Brusa but is
not being used currently as charging
has to be initiated via the BMS touch
screen.
Because I charge on cheap rate
electricity at night by using a time
switch, the charging will not start.
I plan to write my own control terminal
to communicate with the BMS controller
and will build in a time switch as well
as other nice widgets that come to me.
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
thrashed.
I used the original 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
90A at 13.1v
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 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
140A 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.
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
life.
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 trip was a 55 mile run
South of Stratford Upon Avon.
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
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:58,500 Miles (94,126 Kilometers)
Total:10,300 Miles (16,572 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.
TiresToyo Proxes T1-R running at 35psi
Conversion TimeStarted in October 2007, it is now
June 2010 and it is all finished
and working with the addition of a BMS
sourced from China.
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.
£1200 for the BMS system with colour
touch screen

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 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
conversion.
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
sockets.
For speed, I have also fitted a 16A marine grade plug
socket where the filler cap is as it is easier to access
for home charging, which also allows the full 3.7kW
Brusa charger capacity which is externally selectable.

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 test
and it has been re-licensed as an EV.
This gives me free road tax (£210 on my M3) and of course
no servicing bills (my M3 is silly money!!!).

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
book "ELISE. REBIRTH OF THE TRUE LOTUS" by Alistair
Clements.
A brilliant book charting the development of the Elise
from concept to reality.

Next Project.
For 2010 I had purchased a TVR Cerbera which has far more
room than the Lotus for batteries, but it will upset a
few TVR owners if I say that it is an awful car to drive
and I am selling it.
There is nothing actually wrong with the car and it is in
almost new condition but the design and ergonomics are so
poor that if I was in charge of TVR no cars would have
left the works.

I have found a lovely design of kit car (Vortex) and will
design in the electric car requirements from the chassis
upwards.
Watch this space.

code by jerry