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Old 10-19-2020, 09:50 PM   #353 (permalink)
serialk11r
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Quote:
Originally Posted by redpoint5 View Post
I don't know what the Pb-acid battery can contribute, but 100F rated caps probably aren't close to being able to start most engines. Worth experimenting with, but I wouldn't think anything less than 300F rated caps would work reliably.
The original Youtube "Laserhacker" ultracap guy got his Honda V6 to start on 400F caps when it was full, and started his 1NZ-FE on 350F caps at 10.4V.

The battery alone should be able to start most 4 cylinder engines if it's fully charged. I've seen some guy run a Harbor Freight AGM (rated at 10Ah) in his car. You easily have something like an intermittent 50 amps available even if the battery is only half charged.

The 11mohm ESR of the 100F cap means you'll see approximately 1V drop at most, so your usable energy is at least the difference from 12.4 to 8.2 volts or 86.52*16.66/2=720 joules. That's 100 amps available for almost a whole second, which is enough.

Certainly the 58F pack is better, but I think you could get away with the 16F pack if you want to save money. The point is to not add extra power you don't need to the battery to avoid leakage current, cost, and bulk. The more money you spend, the closer you get to the intro price of ~200 dollars for a lithium titanate pack with its greater ease of use.

The 16F bank can also be added to a small lithium ion battery for cars that don't sit very long of course.

Last edited by serialk11r; 10-19-2020 at 10:02 PM..
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