Wait that isn't an F20c Electric car build thread
Posted 27 August 2012 - 07:54 PM
Posted 27 August 2012 - 08:13 PM
Yup, batteries will be located in two rear compartments.
The balance will (hopefully) be somewhat uniform. However, I have strategically placed a majority of the weight directly over the rear axle. I will work on the balance once I finish it.
Posted 27 August 2012 - 09:06 PM
Man I just typed a huge response to this and then I pressed backspace, and Chrome seeked back in history and all my work was gone
Anyway, round 2
Power is determined by voltage and amperage in the electric world.
The battery pack will consist of 416 cells with 4 cells in parallel and 104 in series. Each cell has a nominal potential difference of 3.3v.
Therefore, the voltage of the traction pack = 104 * 3.3
V Pack= 343.2v
Current is determined by both the batteries as well as the controllers. The batteries are 20ah A123 systems pouch cells that I bought from china . 4 parallel = 80ah units.
Each cell has a discharge multiplier of 20-30c, therefore each battery module (8 modules) should put out 1600-2400A.
However, my controller has a limit of 2000A, so this is the system bottleneck. It can put out 2000A as long as you can keep it cool (liquid cooling).
P = I * V
P = 2000 * 343.2
P= 686400 w ----> 686.4 Kw
1 Kw = 1.341 hp
686.4 * 1.341 = 920 hp
Assume an 85% drive train efficiency
920 * .85 = 782 hp
On top of that, the motors can put out 1500 ft-lbs of torque at 0 rpm
So overall, the car has a potential of 700ish hp. I am assuming I will end up getting anywhere from 550-650 at the wheels.
It should be fun
Once its done Ive got something to race it against / compare to.
Ironically, the car that it shall race was also the vehicle that transported the S2000's motors
Can you guess what it is ? :--)
Posted 27 August 2012 - 09:32 PM
The batteries will be A123 20Ah prismatic cells.
These cells will be arranged into 8 modules, with 52 cells each. The cells will be combined using a 4p/104s pattern.
I finished building 1 of the 8 modules last weekend, but haven't put it into the car.
I wanted to have a test drive this weekend, but the drive shaft shop sent me a drive shaft that was 3" short than what I asked for like lol wat. How do you mess that up? However, they have agreed to fix it so we will see how this turns out.
Edit: Here is the drive shaft I received. The workmanship is there, however it is significantly shorter than I ordered / would be considered usable.
Posted 28 August 2012 - 02:20 AM