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To: butlerweave
"The batteries are VERY HEAVY"

Specific Energy (MJ/kg):
Jet Fuel: 43
LiOn Batteries: 0.36 - 0.88
LiOn Batteries: 1.6 (with silicon nanowire anodes)
Zinc-Air Batteries: 1.6
Lead-Acid Batteries: 0.2


It is utterly ridiculous to consider batteries for air flight. And these numbers don't include the weight of the prime mover (jet engine, piston engine, or electric motor) to convert power to motive force. You need a LOT MORE electric motors and propellers than engines and propellers with jet fuel power.

Another poster pointed out that your aircraft weight goes down as you consume fuel on your flight, but battery weight does not change. That further contributes to inefficiencies in battery powered flight.

This is another liberal solution looking for a problem to solve.

14 posted on 11/08/2023 11:08:27 AM PST by ProtectOurFreedom (“Occupy your mind with good thoughts or your enemy will fill them with bad ones.” ~ Thomas More)
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To: ProtectOurFreedom

“It is utterly ridiculous to consider batteries for air flight.”

Economics:

Fuel savings

Lower Maintenance costs


16 posted on 11/08/2023 11:13:52 AM PST by TexasGator
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To: ProtectOurFreedom

Your points are entirely valid there is zero reason to go 100% battery electric all the advantages are in the electric drive train. Electric motors are now 10+ up to the pound in power to weight some axial flux are 20HP/Lb this is why you use them as generators are also in this power to weight class. Gas turbines the very best of internal combustion are 6 to 12 horsepower per lb of dry mass. Piston aengines are in the 1 to 2 range with high levels of turbo boost. A gas turbine powering a axial flux high voltage generator feeding multiple rotors is the answer. Add in a small high power but not high energy battery to smooth out the peaks and valleys of demand while running the turbine at its peak efficiency point. You get all the advantages of electric drive train with none of the extra mass of carrying batteries that have 30 times less energy density not power density. Electric drive trains are so light now the Toyota Camry hybrid weights less than the ICE version of it having had its transmission ,differential unit replaced with dual electric motor/gen and a single planetary gear unit. This also doubles the MPG of the vehicle in urban use. EDUs are mature technology.


51 posted on 11/14/2023 7:13:23 AM PST by GenXPolymath
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