Personally, I would like to see the specs on the voltage regulators before putting a 17.2v battery into a machine which expects a 16.6v max battery. (ok, 16.8v if we believe
@Steve Carr all the time. I am finally getting some of my batteries to show 16.7v after several cycles using the Venom Dual Pro charger instead of the Venom Typhoon Pro 4 bank system).
I do realize there is only a .4v difference, but... if the specs say the higher voltage was not in the design, then we run the risk of over stressing a critical component, do we not?
I also agree with Ty. Still having good results with my Ultrax, but... I seem to be noticing one or two (of my 3) are not holding up (flight time wise) to my slightly puffed original 3rd and 4th packs. (*see note below.)
I am recording the progress of a cabin build this winter and am making extensive use of Tuna's UAV Toolbox. What that means is, i am flying the same mission over and over. I am finding, with consecutive flights in the same conditions, one or two of my Ultrax are having me abort the mission rather than take a chance of being out too far. When I do get the craft back, the packs rebound to the typical 15.2v to 15.4v, which is what I normally see due to my "be home by 14.8v" guideline.
Now, please do not take this as an indictment of the Ultrax. I love them, especially when, with patience, we can get them for under $50 (USD). I am just saying that in my experience, all packs will take on their own characteristics and thus we need to make sure we monitor and are aware. If I need an extended flight, at least right now, I know to use my two year old packs. I also know I need to pay close attention to some other packs to see if my perceptions are correct or if I am just imagining things.
Happy flying!
Jeff
*Regarding the "slightly puffed" statement: For those just coming upon these discussions, please search for LiPo battery care posts. There is plenty of discussion regarding the need to know whether any apparent "ballooning" of the battery pack nameplate(s) is due to actual expansion of the battery cells themselves, or whether the plates have deformed due to the heating and cooling of the packs during use, charging, and cool down.
The two year old packs I refer to above have a very noticeable ballooning of the nameplates, but... there is plenty of give when one presses them. They are also the best performing packs in my thirteen pack inventory.
Disclaimer: every pilot is responsible for the care, feeding, and evaluation of their own fuel cells. Anything discussed here is for exactly that... discussion and experience sharing only.