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The Tesla car being recently shot into space made me wonder about the reliability of common electronic components in hard vacuum. I'm asking about the kind of components you would find in Musks's car-turned-stellar object, not specific components designed for space applications. This is an "out of curiosity" question, I don't intend to build a spaceworthy roadster in my garage.

Would electrolytic capacitors lose their electrolyte and dry up?

Would LiIon batteries' pressure release safety valves pop?

Would chips popcorn due to moisture evaporating in vacuum?

Would the LCD's liquid crystals evaporate?

Obviously, air-cooling of electronics would no longer work.

Radiation would zap CPUs and RAM...

The evaporation of axle grease and coolant shouldn't matter that much due to lack of roads...

"Amateurs" have been shooting GoPros and other electronics into space for a while now, and it seems to work, at least for a few minutes. Still, the camera on the Tesla didn't last very long (just a few hours).

What could have failed first in that camera?...

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closed as too broad by Charles Cowie, Andy aka, Trevor_G, Matt Young, RoyC Feb 11 '18 at 10:22

Please edit the question to limit it to a specific problem with enough detail to identify an adequate answer. Avoid asking multiple distinct questions at once. See the How to Ask page for help clarifying this question. If this question can be reworded to fit the rules in the help center, please edit the question.

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    \$\begingroup\$ Most likely the power source "failed" first by running down. It wasn't intended to operate for long, and was powered from the second stage power system - it didn't have its own battery. \$\endgroup\$ – JRE Feb 10 '18 at 12:53
  • \$\begingroup\$ This makes sense. I thought it was powered by the car's batteries. \$\endgroup\$ – peufeu Feb 10 '18 at 13:01
  • \$\begingroup\$ This question belongs in the chat area chat.stackexchange.com/rooms/15/electrical-engineering \$\endgroup\$ – Charles Cowie Feb 10 '18 at 13:02
  • \$\begingroup\$ There are several questions about the Tesla over on the space exploration stack. \$\endgroup\$ – JRE Feb 10 '18 at 13:21
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    \$\begingroup\$ Another issue you have not mentioned is thermal gradients. The sun-side temperature of the ISS is ~121C, shade side is ~-157C. \$\endgroup\$ – Trevor_G Feb 10 '18 at 16:18
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Tesla/SpaceX had probably removed the battery pack, electrolytic capacitors, other parts that aren't compatible with vacuum and don't die gracefully.

Your question are asked a lot by people who build CubeSats. A lot of them are build with automotive, commercial, industrial components, because CubeSat budgets can't afford the officially space rated parts.

In grad school, I've worked with a team which have designed, built and launched a CubeSat. What little I know about vacuum compatibility comes from that project.

Would electrolytic capacitors lose their electrolyte and dry up?

Electrolytic capacitors outgas in vacuum, so they are avoided in the space hardware. Tantalum capacitors are alright.

Would LiIon batteries' pressure release safety valves pop?

Run off the mill cells outgas too.

Would chips popcorn due to moisture evaporating in vacuum?

That's not a problem. There's not enough moisture to cause trouble.

Obviously, air-cooling of electronics would no longer work.

Spcecraft typically rely on conducted and radiated cooling. Convective cooling is rare, with the exception of heat pipes.

Radiation would zap CPUs and RAM.

It can. There are various techniques for radiation hardening.

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One effect related to power converters in space:

The thermal grease, the layer between power semiconductor module (of the inverter) and heat sink, disapears quickly into vacuum and the thermal resistance increases accordingly. This results in much higher junction temperatures if the motor would consume power. This reduces power semiconductor life time significantly.

E.g. sintering the power semiconductor to the heat sink would avoid thermal grease, but that's obviously not done in the Tesla (IGBT packaging in a Tesla)

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  • \$\begingroup\$ That's interesting. Would silpad sheet work in space? (although its thermal performance is much worse than grease) \$\endgroup\$ – peufeu Feb 10 '18 at 13:57
  • \$\begingroup\$ @uwed The vacuum renders the non-transient thermal resistive properties of the heatsink useless because of zero air flow so your point is rather weak. \$\endgroup\$ – Andy aka Feb 10 '18 at 14:24
  • \$\begingroup\$ True, but the heat-sink it's attached to is already screwed without air to dump the heat into, so the lack of grease won't make much difference. \$\endgroup\$ – Trevor_G Feb 10 '18 at 16:12
  • \$\begingroup\$ In a real space application (which the Tesla is not) the heat sink would be a heat spreader plus radiating surface, no convection, of course. Then, one might try to avoid grease between the power semiconductor and the radiator. \$\endgroup\$ – UweD Feb 10 '18 at 17:09

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