OwnerBob Simpson
LocationBanks, Oregon United States map
Web/EmailWebPage email image
Vehicle2003 BMW 325i
A young sports car transformed into a full performance electric drive with all original functions and features.
Much more complete specs description on my website.
MotorSiemens 1PV5135WS28 3-Phase AC
This AC Induction motor is built for 700 Volt operation for even less I2R losses. Has a 10,000 RPM upper limit but I limit the RPM, via inverter setting, to under 9000 for sake of clutch basket stress concern.
DrivetrainRWD, using original manual 5 speed transmission. Motor is positioned and supported by original motor mounts and mated directly to transmission.
Controller PM100 100kW
This compact water cooled drive inverter is courtesy of Rinehart Motion Systems. A very well engineered package that is proving to be robust and reliable.
My original design uses a 200kW drive unit that will eventually drop in, replacing this 100kW unit when it's Software is ready in late 2010.
Batteries2040 A123 Systems (my custom EVD5 modules), 3.30 Volt, Lithium-Ion
This battery pack system is modular and scalable with very high power capability. BMS software tracks cell behavior for precise and automatic balancing and health monitoring for trends and deltas.
Pack has 1200 A peak and 700 Amps continious rating.
System Voltage673 Volts
ChargerBrusa NLG514-WA
Water cooled 3.3kW charger. Input source is 220VAC or 120VAC. Output has just enough voltage to top off the pack at 710V.
HeaterMES-DEA RM3 4kW fluid heater for cabin heat/defrost, also has electrically heated seats.
DC/DC ConverterBrusa BNW415
This is a 1200 Watt unit. Puts out 13.75 volts whenever ignition switch is on.
InstrumentationOriginal except for replacement of the tachometer(behind panel) with a multi function programmable display (EVision) developed by Metric Mind Corp.
Top Speed125 MPH (201 KPH)
This is my estimate with the 100kW drive. I will update it when I get a chance to get that speed.
I have easily passed the 100MPH threshold in 4th gear (out of 5).
Cruises effortlessly at freeway speeds, quick passing and high speed hill climbing put little stress on the cells, demonstrated by the tiny temperature rise in the LiIon cells under hard use.
AccelerationCurrently similar to the original off the line performance. Expecting 2x with 200kW inverter once installed.
Range50 Miles (80 Kilometers)
This range is based on 60-65 MPH level freeway speeds. Specifically sized for a 40 mile daily commute.
Watt Hours/Mile300 Wh/Mile
Initial measurements. I am now gathering more accurate data and will post results both here and on my website
EV Miles
Start:38,300 Miles (61,624 Kilometers)
Current:38,992 Miles (62,738 Kilometers)
Total:692 Miles (1,113 Kilometers)
Seating Capacity5 Adults very comfortably.
Curb Weight3,400 Pounds (1,545 Kilograms)
Slight increas in front (100 lbs) and less in back by 75 lbs. I haven't noticed differences in handling yet even though I have pushed it pretty hard in the twisties a few times. I will be adding an aux pack in the rear (where gas tank was) that will help equalize the disribution (not to mention doubling the driving range)
TiresStock, for now. Nearly ready for low rolling resistance equavalent set.
Conversion Time2 years. Much delayed from lack of 200kW Inverter (ordered and eventually delivered but not functionl) Instead have installed a 100kW to get rolling. Lots of hours, never counted up.
Conversion Costover $50k above the cost of the BMW itself. High cost but high end and long lasting
Additional FeaturesThe only sign of the electric components is the DC/DC converter in the trunk, sitting directly above the 12V lead acid battery cover. Nothing different in functionality (except for dead tach), including all the heating and cooling functions using original controls.
The only feature I lost is the cruise control. I will implement it with CAN control using original BMW resources under my control when I get that code written.

Many things worked out without touching the BMW wiring harness. I removed the original BMW ECU and plugged the chassis I/O connector into my new control board, sized exactly the same size and the old ECU to slid right into the same slot. The Master supervisor processor resides in the neighboring slot where the automatic transmission controller would be, IF it were an automatic (which it is not).

The original air conditioning system will be used but with a compressor driven by an imbedded variable speed AC motor that gets power from the traction battery pack rather than a compressor driven off the ICE. This is a very compact unit made by Masterflux, model Sierra 06-0982Y3.
This conversion is described and detailed on the WebPage website along with a high performance off road motorcycle development.

code by jerry