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Originally Posted by redpoint5
Is that the single capacitor impedance, or the total impedance of 6 capacitors added in series?
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Nice catch. Yes for 6, it would be 6 times less or 95Amps. But this works both ways, if the impedance is too high the capacitor wont be able to deliver the rated current to the starter with an acceptable voltage drop.
My lithium pack has 24mOhm (12mOhm/cell in 4S2P) and turns the starter a bit slower than the 70Ah battery it replaced. At 10C discharge rate, the CCA would be about 200A with a terminal voltage of 10V.
Quote:
Originally Posted by redpoint5
I believe you, but I'm going to verify this sometime when I am messing around with caps and starting again. The alternator in my TSX varies output modes depending on electrical demands including the state of battery charge.
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Those receive the signal from the ECU, having the aim to unload the alternator during acceleration/heavy engine loading and the opposite during braking. I'm guessing it makes it easy that something set to 14.4 all the time.
Normally the issue is during high rpm (2500+). The easiest way to try is to get a clamp meter and start the car with a bit of throttle. Current should drop fast on a capacitor, however. A lithium pack is probably more of a problem as current is sustained for a few seconds/minutes. When I have some time Ill try to log this on mine.
Quote:
Originally Posted by redpoint5
The cheapie panels I see on Amazon for $20 don't have any regulation, but balance circuits are fairly cheap for the common supercap sizes on the market and can easily handle a few watts of extra juice.
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A simple 5W zener (or two) such as a 1N5352 across the solar panel should work fairly well.
Quote:
Originally Posted by redpoint5
I had wondered how much of an issue freezing was considering that the battery will quickly heat up with use. I'd still be hesitant to run it during the coldest days in the Portland area, which might be 15 F. I'd have no concern if with the battery in the passenger compartment.
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Well, one could always use the capacitor and use a removable lithium battery to top it up if required. This could be a small pack, charged at home rather than in the vehicle.
The lowest I've run mine was -8C (18F), on engine bay, covered with some cardboard. CCA capacity goes down a bit (still enough to start).