Happy Independence Day to our US readers! We hope that everyone will take this time to think of ways they can help reduce our dependence on foreign oil.
As some of you know, I've been working on a project to take an older Porsche Boxster with a bad engine and convert it to a battery electric vehicle. I have some good news on the project. A couple of weeks ago, the EV Boxster took its first shakedown run on the road. I have some video to show of the event:
The shakedown run uncovered some power issues. Whenever the driver stepped on the accelerator to give it full power, the computer would only give some of the power to the engine. We were able to get it up to around 50mph and it took too long to get there. If you are familiar with the torque of an electric motor, stepping on it should burn some serious rubber and launch it to 60mph in just a few seconds.
After doing some debugging of the drivetrain's computer management system, we were able to resolve the power issue. Here's a video of the beast strutting its stuff with the pedal to the floor!
I will be posting more information about the EV Boxster over the next couple of months. For those interested, here is a quick description of the components in the conversion:
108 3.2v, 100Ah cells (ThunderSky)
Nominal voltage: 345V
Peak voltage: 400V (occasional finishing charge to 450V)
Low voltage: 270V
Weight: 713 lbs
15 Minute rating: 3C; 140 HP (105 KW)
Impulse rating: 10C; 420 HP (300 KW)
Max charge current: 3C (20 minute charge): 300A @ 400V; ~210A off 480 3phase (many commercial circuits are 500A 480-3phase)
Optimal charge current: 0.3C (3 hour charge): 30A
Total Capacity: 34.5 KWh; usable capacity (80% DOD): 27.5 KWh (88 MJ)
Estimated Range: 100 miles
Motor weight: 176 lb (MES-DEA 200-330 – 3phase AC motor)
Inverter weight: 22 lb (MES-DEA TIM600 – 100 KW w/Regen)
Inverter Rated power: 100 KW
Max Torque: 221 ft-lb
Max RPM: 9,000
Shift RPM: 3,000 (for maximum power)
220 or 120V, settable current up to 40A.
Charge time: 4 hrs (220V, 40A) , 8 hrs (220V, 20A), 20 hrs (120V, 15A)
Let us know your plans for reducing energy usage and cutting back in petroleum consumption.