A Hundred Car Batteries Wired in Parallel

What happens if you wire 100 car batteries in parallel and then short them with a conductor? Well, let’s see…a naïve calculation says you should be able to get around 85,000 amperes at 12 volts, or about one megawatt. The entire battery bank stores about 320 megajoules of energy.

By comparison, a typical lightning strike delivers on the order of 30,000 amperes and a gigajoule of energy.

At these current levels, often-neglected electromagnetic effects become significant.

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At this time code he states what I rather expected, which is that the internal resistance of the voltage source became limiting. To which I have just one word: ultracapacitors

That’s what I would use to simulate a ball lightning strike with helical copper wire (with adequate safety configuration to account for a potential explosion of the capacitor bank).

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I am not going to watch, but the splash card is not 100 batteries in parallel.

2 banks in series.

Each bank has 10 groups in parallel.

Each group has 5 batteries in series.

Assuming nominal 12V we have a voltage drop of 120V.

Am I missing something?

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The original plan, and configuration, was 100 batteries in parallel. In the first part of the video, that’s what he’s using, but he finds that regardless of how dead the dead short he puts across the bank, the most current he measures is around 15,000 amps. He concludes that this is probably due to a combination of internal resistance in the batteries and interconnects and inability of such a low voltage to maintain a solid connection to the object being tested.

To try to work around this (the explanation starts at 7:00 in the video), he rewires the bank into a series-parallel arrangement with 5 banks of 20 parallel-connected batteries yielding 60 volts. The balance of the video is testing this arrangement, which on some loads produces around 45,000 amps sustained for more than a second (starting at 20:00).

Even this wiring fails to reproduce the lightning strike that crushed a tubular metal lightning rod by magnetic Z-pinch (34:00 in the video).

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Ultrapacitors have extraordinarily low internal resistance but I think in order to simulate a lightning strike you need to go to an Ultra inductor with some kind of monster Mercury switch.

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