I’ve “lurked” on this valuable discussion for some time and finally decided to offer my 2 cents…but not much more…
Rob (below) and others have captured my thoughts and feelings very well…I made some changes during construction of my airplane that would make others squeamish…and rejected some likely-good ideas that were beyond my knowledge or risk tolerance level.
On experimenting with batteries (and electrical systems in general) in airplanes, I offer the attached pictures. This was the result of a (standard aircraft 24v) battery fire in an IV-P. Total time from smelling smoke to getting the airplane on the ground was less than 10 minutes. Some have estimated that the pilot may have had as little as a couple more minutes in the air… Experiment with caution in this area… J
Bob
<<I do not want to start an argument, but it is frustrating for people to say they don't like ideas based on out-of-date or incomplete data. I am building an experimental aircraft to test and learn new things, for the pure joy of experimenting. Please don't try to stifle experimentation without doing your research.>>
No offense is taken. No argument is intended. Just a clarification.
My motivation was simply to point out that there is a significant risk that needs to be researched and mitigated by anyone who wants to make their own battery pack from new lithium battery cells. I thought the original poster of the idea might be unaware of this particular risk. I think I qualified my statement by saying that modern lithium batteries were outside of my area of expertise, and that while the risk/benefit of building my own battery was not favorable for me, it might be for him. That's all. I suppose I came across as a wet blanket, but the downside risk is considerable in this particular case. He may be a professional battery engineer (or have a friend who is), knows that it will take a huge amount of effort to get it right, but be willing to do it anyway. (Then he can sell his idea to a battery manufacturer and we'll all be buying his product, eh? Capitalism at it's best!)
I'm doing some things on my Lancair that may make another person squeamish. We all are. But they are different things for each of us, partly based on our own level of comfort but also based on our own experience and knowledge. That's the beauty of the experimental movement. We can do what we each think is safe. But I welcome anyone who says "this idea of yours may be dangerous, please check it out and make sure it's safe". That's all I was trying to do.
I was also trying to express a legal disclaimer like Brent Regan's "I am an idiot, I know nothing", which in Brent's case most of us don't believe anyway.