lithium metal batteries

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Well-Known Member
Dec 29, 2019
take in mind that useable energy density only goes up for batteries and other solid state energy
storage devices
with the upper limit on energy density quite likely
higher than gasoline.Exactly how many coulombs
of electrons are in any pound of matter is known.
and we are getting better and better at extracting
some miniscule proportion of that energy


Well-Known Member
Supporting Member
Feb 24, 2008
Kanab, UT
Batteries are always getting better, will continue to do so, and will some day in my life be relevant to the type of flying I enjoy.

That said, competing with gasoline is a big ask. The hydrocarbon oxidation reaction is an electron-transfer reaction just like discharge of a battery; but we don’t need to carry most of the inputs (the oxygen) up with us, and we don’t have to carry the outputs back home with us. In exchange, we throw away about 65% of the energy released… but in terms of useful energy per pound carried, it’s going to be hard to compete with any binary battery.

One can start talking about metal-air batteries, which fix half the problem; but then, one can also look at fuel cells, which fix the efficiency problem with hydrocarbons.

Anyway: All battery improvements are welcome, and we’ll continue to see many more; but don’t bet your retirement on getting has-equivalent range from a battery-powered plane any time soon.

Jay Kempf

Curmudgeon in Training (CIT)
Supporting Member
Apr 13, 2009
Warren, VT USA
Batteries will get a little better based on volume. They aren't going to get dramatically better if Lithium is the horse to ride. The real opportunity is to make the safer with less containment and less worry about runaway "welder" events.

As you stated, competing with gasoline is a big ask. Currently somewhere around 22x by mass in the lab. Way more in real world applications. The periodic chart is a beeeaaaaatch.

Fuel cells farther into that corner of the periodic chart. Volatility is still a tough mistress.