"Legend Length" wrote

I have been trying to do some calculations of how much battery power
would be needed to keep a hang glider flying level. With some help I
arrived at about 1 or 2 kW (a few horse power) for a typical hang
glider with 10:1 glide ratio and 180 pound (80 kg) pilot. As a
comparison, gasoline engines for hang gliders are 10 kW and give 1 - 2
m/s climb for half an hour on 4 litres of fuel.

I am unable to find electric versions of those powered harnesses being
sold. Looking around for battery prices I found this site:
http://www.hobby-lobby.com/flightpower.htm . The last battery on the
page is 22.2 V, 7.4 Ah = 164 kWh. I thought it may be interesting to
see how they would hold up when powering a human aircraft.

First, let me say that you may be able to find a deal on bulk quantities of
this type of cell, that are not already packaged into the packs being sold.

Next, I suggest that you do careful research about the brand and discharge
rates.

The electric RC community has nothing positive about that brand of cell.
Lots of premature failures. Plus, the discharge rate of anything above C-15
will kill the batteries quickly.

You also need to consider the charging of that many batteries. The cost
will be a significant amount of your budget, as these batteries will catch
fire if not charged carefully with an appropriate charger.
--
Jim in NC