I am starting my first own build. It'll be my second Quad after flying, and more than that fixing, my second hand Eachine Wizard. This one is suppose to be an INAV 7" cruiser with long flight time, longer range & GPS rescue.
I intend to try flying Li-Ion battery packs:
4S2P of Samsung INR21700-40T, should give 8.000 mAh at a max. current of 70 A (14,8 V) for a cost of 34 € and a weight of around 540 g,
5S3P of K-Tech INR18650P, for the cost of 24 €. This pack should deliver 7.500 mAh at a max. current of 38 A (18,5 V) , at a weight of proud 600 g.
The 3D printed parts are printed with Filatech's FilaFlex40 material - Really great for this purpose! If somebody is interested in the 3D parts - Just let me know.
First test flight on 4S LiPo packs. It flies really nice. In comparison to my 5" quad, it's more stable, much smoother and much, much more quiet. Unfortunately on 200 mW or even 500 mW, the video reception wasn't all that great. I had quite some interruptions. And as I don't have working DVR yet, I'm taking it really easy.
First test with the 4S2P Li-Ion Pack gets me round about 30 min. of flight time. Return To Home and Failsafe configured and working, the DVR as well. The range is troubling me now. Both video and radio connection started to fade at about 0,5 km in clear sight (with 500 mW tx power).
I might recommend the molicel P42A 21700 cells. being in the electric paramotor industry, I can say that they outperform the samsung 40T in almost every way including cost, peak and continuous current, capacity, and weight.