Quick Charge 5C - less fly time?

[roryhinds]

I'm still fine tuning my SkyJib 8 with AXI 2826/12 motors and 15x4 CF props and I have 2 x 8000mah 25-50C 5S batteries.

On my first flight I got 12 minutes flying time after charging both batteries at 2C which took 1.5 hours.
I then did a quick charge and at 5C which took 30 min to charge both batteries on a due charger but I only got 7 min flying time.

I wanted to ask... if I quick charge at 5C does this mean I'll have less flying time?
Or is there something else wrong with my setup.

 

[kloner]

what charger are you using?

 

[roryhinds]

Hyperion EOS 720i Super Duo 3 with a eFuel 60amp 1200 Watt power supply.

Batteries are Turnigy Nano Tech 8000 mah 5S 25-50C

 

[kloner]

That's a nice charger. Read the manual about how to read IR and go over your packs and measure them all out. When you see this, remeasure. I write the numbers and date right on the pack or make a log. keep track of what pack does what

In regards to the charge, the faster and harder you push it the less reliable it is as far as how much power is in it, I never had good luck pushing nano tech packs very hard before the ir went out of range...... the other thing is it can damage a pack and you want to take note and get it out of circulation. also more weight or slightly harder flying eats a packs airtime just from going from 50 amps to 100 amp draws in a rig this big. The cinestar i work has the same packs.

 

[roryhinds]

Thanks Kloner, I really appreciate you helping me.

I did a recharge of the 2 packs in sync mode at 5amp charge and flew again and only got 7 minutes of flight time with the batteries being at 27% capacity when I landed. Yes I would want to land a lot sooner but I'm really not liking the short flight times and feel something must be wrong as I did get 12 minutes on my first flight.

I'm charging again at 4amps in Sync and will test again.

I did check the IR on my charger and it said 0mΩ on both batteries and they were at 18.866V and the batteries were at 27% capacity.

Could it be that these Nana Tech 8000mah 25-50C 5S batteries are not very good for my SkyJib 8 with AXI 2826/12 and 15x4 Carbon Fibre Props?
I find it strange that I did get 12 minutes flying time with them and now only get 6 or 7 minutes.

How long flight time do you get with your Cinestar and what is the spec?
Could you offer me some advice please.

 

[roryhinds]

Could someone please explain to me...

I'm looking at the C rating now and wondering if I would get longer fly times with higher C rated batteries.
These 8000mah Nano Tech are rated 25 - 50C

If I were to get 65 - 130C in 5000mah 5S and double up so have 4 on the SKYJIB 8 at a time... That would be 20,000mah at 65-130C but weighing 2848 grams... how much flight time would I get over my 2 x 8000 mah 25-50 (1848 grams)