Electric Vehicle Battery specification (very basic)

[Ken Freeman]

What's it called? Some brief Googling is turning up a wide range of stuff, not obvious if they're what I'm thinking of.

 

[mheslep]

Carnegie Mellon has an online research project that provides much of that information.

What's it called? Some brief Googling is turning up a wide range of stuff, not obvious if they're what I'm thinking of.

http://chargecar.org

To role your own driving profile:
http://chargecar.org/participate/how_to

There are plenty of canned driving profiles uploaded to the site, eg:
http://chargecar.org/data/327

Driving Date: 2009-11-05
Location: Rockville, MD, US
Traffic Type: Light
Route Type: Commute
Route Setting: Urban
Car Type: Compact
Car Make: Saturn
Car Year: 2004

with these stats

Total Distance: 3.13 miles
Trip Duration: 0 hrs 4 mins 21 secs
Time Idle: 0 hrs 0 mins 12 secs
Net Elevation Change: -74.32 feet
Average Speed: 32.17 mph
Max Speed: 69.3 mph

Which, if traveled using CM's E-car model would use energy accordingly:

Energy Consumed: 1.06 kWh
Total Charge: 0.05 kWh
Total Discharge: -1.1 kWh
Percentage of Power Regenerated: 4.09%
Peak Power Usage: 85.31 kW

There are numerous online plots available as well - acceleration, speed, etc.

http://chargecar.org/data/do_graph?meta_data_id=327&data_type=gps_datas&graph_type=power_over_time&file_name[name for the profile above.

 

[mheslep]

...I do have the same kind of project which is to propose the powertrain design of an electric bus.

I am kind of lost, do not where to start. Of course, I have read so many articles though. So I think I have some background knowledge, but I just want someone to point out how I can put these jigsaw pieces together.

Is it possible to tell me how I can calculate how big the motor will need to be? Are we talking about its delivered power in kW? Is rated power simply a maximum power?

All so, how do I do the same for a battery and a fuel cell? ...

Montreal committing to all electric bus fleet (1300 strong) by 2025.
http://gas2.org/2010/05/25/montreal-buses-to-be-completely-electric-by-2025/#more-8096

Montreal is looking at fast-charge buses that can store enough power for a 20 kilometer route before recharging in 10-15 minutes at either end of the route.

which are fairly tame (unrealistic?) requirements. Twelve miles would require a very small battery pack, say 6 kWh assuming 2 miles per kWh in a bus with good regeneration braking, plus some margin, call it 10 kWh. Such a pack would cost maybe $5000, weigh 100kg. To charge in 15 minutes would require a 40 KW line (480 V at 83A). Might be easier to go with a battery exchange. Replacement cost is a problem though with these small batteries. Assuming a maximum of 3000 deep discharge cycles for any size battery and three charges a day, they'd get no more than three years out of the battery, worse with the quick charge stress.

 

[Sixdeuce062]

So to be blunt yes u can build it to do that but keep in mind u will have lots of batteries ( half the cars worth) every thing in the car will have to be light as possible ( the lighter it is the more dangerous it gets think about it ) and it gets very expensive but it is possible.

I was in a high school class that build one of a go kart out of used and donated parts form an electric fork lift and other stuff in 03 got 10 mi. before batteries died and top speed of 20 mph so yeah you can but its not going to be very cost effective