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> the "battery" in the old ones is nuclear and it's going to be difficult to beat that

Newer atomic batteries can theoretically last centuries instead of decades.

V'ger 1 atomic battery is based on Plutonium-238 which has a halflife of ~88 years. It's down to ~210W output from initial 470W at launch time.

Americium-241 has a half-life of over 400 years.

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The longer the half life, the lower the power output, no free lunches. But by putting the same suitable radioactive lump in a stirling engine you can extract 4 times as much electricity: https://en.wikipedia.org/wiki/Stirling_radioisotope_generato...

So yes maybe with Americium-241 we could have something which lasts 4 times a much _and_ gives us the same amount of power thanks to a SRG.

But it seems to involve moving parts, so I am not sure the reliability trade-off is worth it for decades/centuries long missions.

Yes, it's being tested (NASA ran one for ~15 years continuously, which seems promising, I don't know if the test is still running), but I don't know if any were actually launched and are used in space.

That seems actually quite impressive.

Using a sterling motor would give you mechanical wear.

Finding “V’ger” hilarious.

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