Electric Motor Battery?

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Armilite

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Joined
Sep 5, 2011
Messages
3,643
Location
AMES, IA USA
So if these Aluminium Air Batteries aren't available right now, are these Iron Air and Zinc Air available in Sizes we can use to make Battery packs for Homebuilt Airplanes? What are their Costs? Right now the Lithiums seem to be the Best Option.

When it comes to this Electrical stuff I'm just a baby learning, so be nice. I found some info on using a 100hp Electric motor and put it into a SpreadSheet using the different most common hp used. I used 5min for Taxi, 5min for Takeoff, 1hr of Flight, a 15min Reserve, and a 5 min Taxi time back to the hanger. Now how do we figure out how to make battery packs for that Time/hp used?

I haven't done much research on all the Motors available. In the Article, they had this Red 54hp Electric motor. I don't know if it's the same motor that I saw years ago that was rated 25hp - 75hp on the Electric Spyder. The Rotax 277UL was rated [email protected] and was used on probably 85% of Part 103's. it actually Dynoed 25.4hp. There was also a [email protected] 277UL. So I figure 25hp as being the lowest anyone should use. Using the 1kw for 10kg Rule of thumb I also made a chart.

I also included my Excel file.
 

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n3puppy

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Joined
Jun 25, 2019
Messages
270
How many batteries? - really need more info like motor/controller voltage and battery design
Example-
22KW Aerolite uses 72volt system,but Blue Shock Karts 25kw system uses 96Volt.

The 3.2 volt batteries you picked out -
72 volt = 23 batteries minimum ( 72/3.2)
96 volt = 30 batteries.minimum (96/3.2)

That just gets you voltage - then you have to figure motor amps required and amp/hours used.
Math not much harder than sizing a generator, Watts = voltage x amps.
BUT THAT IS IN A PERFECT WORLD.
Need lots of other data like motor and controller efficiency % to be precise to decimal point accuracy.

Aerolite connects twenty 3.6volt batteries in series to get 72 volts.
Then connects 12 of those strings in parallel to get enough amps output and amp/hour capacity.
240 batteries total.
Result is their battery pack is 36amp/hours @ 72volts

Their published flight data is pretty close to simple math in spreadsheet
Two 36ah batteries = 76ah. 76ah = 30 minute total flight.
Your profile with 1 hour flight, higher 75% cruise, reserve etc would need roughly 321 amp/hours.

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