saw headline, haven't read it yet but one thing prompted me to post; an 88 y.o. gentleman I know is an areonautical engineer, formerly chief engineer at 3 companies, owned a few companies and worked for NASA. One of his NASA projects had him design a lunar drill taking into account lack of atmosphere on the moon and (lack of)heat dissipation of that scenario. Air is good to have when one wants to lose heat, perhaps even air pressure would be a factor in cooling rate??? - always enjoy the minds at work in t his column
Yikes! Glad to hear that you're okay after that explosion!
I'm amazed at how volatile LIon cells are. But, at least on the ISS, if they're going to be mounted outside of the cabin, in an unpressurized area, doesn't that mean that there will be no air/oxygen to assist in combustion?
Until yesterday I thought that the warnings for lithium batteries were a little exaggerated, but I had my own experience. Yesterday afternoon I had a small cell blow up in my face. Yes, that could have happened with nearly any chemistry, but aside from the lithium that was burning on my workbench, for the next several seconds fire was spontaneously erupting on the floor and any other place that had been showered with lithium. I had lithium in my eyes, so I opted for an eye wash and came back to extinguish the flames after I got the crud out.
My eyes and face look pretty bad, but I'm actually OK. Like I said, this could have been any chemistry, but the big difference with lithium is how quickly things can go wrong and how incredibly reactive the stuff is. Simply being exposed to air seemed to be enough to cause the lithium to spontaneously combust.
I'm very surprised abut the introduction of Dreamliner Battery Packs in ISS.
For satelites make sense no human life is involved but ISS? I'm not confident with the ability of such a battery to work in space at temperatures outside the normal lithium battery operation range in plus and minus grades.
Thanks for the feedback from someone who has been involved in the design of these planes. And yes, obviously the weight savings for the ISS is a very high priority for NASA, perhaps more so than for aircraft. But the ISS' dollar value must be one heck of a lot higher than the dollar value of a single jet family. I'd also argue that there are also some not always appreciated concepts of risk assessment. If the risk of something happening is very low, but the result of its occurrence is very bad (like a damaged ISS), then simply talking about the low percentage isn't enough to make a rational decision.
Re: Risky Choice The risk you worry about is very small and won't affect the Station Inside.
The savings in weight are very important launching to orbit.
If you dwell on the fact that Thousands of flights and hours in ground service during development testing showed no problem, then two planes from one Airline had problems within a week, you might suspect that an abnormal, systematic fault in service happened. The answer in engineering terms was to design a system that allows the fault and prevents further damage. As an ex Boeing Engineer, I was surprised by the Airbus back step.
I agree with risky, so I'm surprised NASA is doing this. A major Boeing competitor, Airbus, dropped plans for Li-Ion batteries in its upcoming A350 XWB widebody jetliner, and went back to its Plan B: nickel-cadmium batteries.
Well I think this is a gutsy and risky choice on NASA's part but hopefully they will ensure the design of the batteries they use doesn't have the same kind of problems that the Dreamliner batteries had. Hopefully they will learn from past mistakes!
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