Any recommendations for Li-Ion battery pack vendors? Plan to design an aircraft that uses around 2.4C max - so I would need cells that can support at least 3C. So far I have found the following to the be the best vendor (from my research) - albeit the higher cost.
Edit: I am looking for pre-made packs. Not looking to make my own for this project.
“sony vtc6” try with this.
in Europe we have nkon.nl, it’s a great supplier with best prices in Li-Ion.
18650 and 21700 oder 20700 are available in different chemical variants. You can either have high maximum current (low internal resistance) oder high capacity. It’s up to you to choose what you need.
For most planes the high capacity batteries deliver enough current, but for VTOLs and Copters not!
High Current cells:
Sony / Murata US18650VTC6 3000mAh - 30A
Molicel INR18650-P26A 2600mAh - 35A
Sony / Murata US18650VTC5D 2800mAh - 35A
LG INR18650-HG2 3000mAh - 20A
Molicel INR21700-P42A 4000mAh - 45A
Molicel INR20700A 3000mAh - 35A
Samsung INR21700-40T 4000mAh - 35A
May I ask why the overall statement of high capacity batteries not allowing enough current for VTOLs/Copters? I have tested my aircraft with LiPo over the past year - and the max draw I have ever seen is 2.3C (during a fast takeoff). Would the 3C rated batteries not support this?
Seems very very low to me, most copters need 10C or more.
Don’t forget the peaks during wind, heating up of the batterys during discharge (resistance inscrease) and still enough power to keep the vehicle flying even at nearly discharged battery.
To cut the long story short, it mainly depends on your flight time. If your hovering time (VTOL) is longer than one hour, it might be possible.
I mean I have the logs to prove it - so I am not worried about exceeding 2.5C. Just looking for reliable and well built packs.
Also is hover time is longer than an hour - that would mean that you are pulling <1C.
See Mavic Air 2 that uses a Li-Ion battery and has an approximate hover time of about 25 minutes.
The max we have every seen on our aircraft during flights in high winds, fast takeoffs, etc. has been 1300W - and this was on a very windy day where we were flying upwards of 40MPH. At a dead 6s voltage of around 18.5V - that would lead to a current draw of around 70A. We plan on putting a Li-Ion battery pack that is around 30Ah on the aircraft (same weight as our current 6s 22Ah LiPo).