So no, I do not NEED 20secs. of boost. The number was wishful thinking and for if I used it for some standing start racing(1/2, 1 mile). For 7secs what do you think the weight will be?

I’ll go into a little more detail/more specific. Assume a 90% motor controller efficiency at full power

7sec would be 0.001944 hours.

250HP(186kW)/0.90 = 207kW from the battery

One pulse drains 402 Wh from the battery. At max you want to use say 10% to 95% of the battery. Buffer on each end for imbalance, error and to improve battery. But you at racing so gave you down to 10%. So 402Wh/0.85 operating window is a 473Wh battery. The titanate cells are 70Wh/kg. So that’s 6.7kg minimum based on energy needed.

Let’s look at power now. 207kW/473Wh would be a 437C battery. Not possible. If the titanate battery can truly do 50C peaks then you a battery that is 437/50 = 8.75x bigger. So that’s a 4.14kWh battery at 59kg.

So honestly that’s not much lighter and that would give you enough energy to make a 20sec+ boost. The key is in what the try C rate is of the cells.

The 2.9Ah Toshiba Titanate cells have a 65C rate at 50% SOC for 10sec. So let’s say at higher SOC and 7sec you can do 75C. You’d need 2.55kWh to make the power. But at 46Wh/kg you’d be at 55kg or battery.

So I guess I can figure out what 55kg of supercaps would get you in terms of total power for how long.

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