Hey everyone, glad to be here, very interested in E-PPG. Great job on this design @Pdwhite, looking forward to buying a kit!
I stumbled across this video a few years ago regarding a company who designed cylindrical batteries for ultralights that were scalable to any size or power combination. The link should open to the point where he starts talking about them. I am interested to hear your thoughts if this is a viable alternative for the battery in this open design.
This video shows him flying an ultralight about 18 months ago along with more data on the motor and batteries.
I reached out to the owner, Chip, and he has some of these packs available for sale. They were designed specifically for flying and to minimize risk of fire. Made from Lithium, Cobalt and Nickle, they claim it has the highest power to weight ratio energy density of any battery available. He has developed a smaller battery with higher voltage for his new motor recently and he is getting back to me on the specs and pricing for all of those.
I am not an electrical engineer, I put together some of these specs from their old website a while back, hopefully they will be helpful. Feel free to correct anything if needed.
Ultra-Flite Battery Cylinder -
12s - 44.4V 65Ah draws 130 amps
2886 w or 2.9kw is around 44 lbs??
14s -57 V - 51 lbs, each cell is 3.5lbs 3705W or 3.7kW
firstname.lastname@example.org = 52.65V or 14s = 56.7V
On the 2nd video he mentions getting 1 hour of flight time w 21 packs in his ultralight then 2 hours to recharge. You can scale the number of cylinders up or down as needed.
Here is another link with more specs on the battery from their website.