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Old Jan 26, 2012, 03:05 PM
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Joined Jun 2009
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Battarizas Battery list or batteries battery w/ flight vids

[Search ref Battery, Batteries, 6S]
Battery tray dimensions
Length 200mm x Width 58mm x Height at Front 75mm, Height at Rear 65mm

Center of the tray is 250mm forward of CG-155mm.

Understanding your battery choices.
Capacity mAh and C rating: Any batteries capacity in amps times the C rating equals the amount of amps said battery can deliver.
((XmAh/1000) x C rate) = amps delivered by battery.
Its important not to use your batteries past the last 20% of the capacity or the battery can be permanently damaged take less charge each time.

How long can you fly: Depends on how you are flying. Wide Open Throttle or WOT looks at the maximum your motors can demand. Stock for this model is ~80-100amps.
Run time at this draw rate is calculated (((mAh/1000)*.8)/amp demand* rate)*60=X minutes. e.g. (((5000/1000)*.8)/100amps)*60= 2.4 min
So thats 2 minutes 24sec at full WOT.

......
Example that many pilots followed:
Stock demand* rate of 100amps max WOT
a 5000mAh battery 40C
has only 4000mAh usable capacity (5000*80%)
will produce 200amps at the start (5amps*40C) but the motor can only demand* 100amps.


An Additional Note:
*Thanks to a myth bust from Pete and Jcdfrd; the idea of amp demand. This is really driven by what volts your battery can push under load. Not all batteries are created equal and specs can be decieving. As the links below show in the battery shoot outs, lower C ratings of one brand or even within the same brand, can hold there own because the voltage "sag" isn't as significant as others and thus run longer. But generally a higher C rated battery usually heats up less and has a lower IR and thus manages to provide more volts to the motor. More volts can mean that it has a higher rpm (kv X V) and thus may demand more amps and thus overall has a higher amp reading.
Word of caution using lower C rated batteries. Batteries have a peak rating. So you may have a 40C/60C rated battery. 40C is normal continuous draw. But as you draw down more the sustained voltage demand nearer to the end of your flight has depleted the mAh capacity of your battery an thus to maintain performance is then going into a "sustain" peak performance window that for a LiPO can start changing the catalist and with increased temps in peak the LiPO paste can start to cook even before showing signs of balooning. When this is done repeatedly, your battery may then take less and less capacity while charging.
Thus on this thread and some of the shoot out forums, over heating and IR become bigger factors.

We generally don't fly at full throttle the entire time. Thus mixed throttle settings flying a mix of 3D, speed passes while off the throttles where possible or a few slow turns or passes, pilots generally found such a battery to run about 4 minutes (including landing safety margin AKA go arounds). Thus throttle management is always advised.

For a Deeper understanding of battery performance see the following RCG threads that look even more closely at battery theory or brand performance. (13.01.30)
esr ir meter for lipos and Lipoly Objective Performance Database threads.

The Battery Comparison Test: X amp Nominal Constand load that you just linked to, is the simplest compare chart. Clearly its not all about the C rating.

Draw formula's using measured battery IR.
Max Amp draw = Square Root of (6xCapacity/IR) Ref magic formula


__________________________________________________ _______________

Summary batteries used by pilots reporting in this thread;
Commentary is certainly invited and PM me with battery experiences to add.
Sorted by Weight

Factory Stock motor demand ~98 amps max:

The GensAce 3800 25C (95amps) at 626g Shorter flight about 3 min ref jws39 Youtube Vid.

The Genisis 4000 40C (160amps) at 626g ...

The Genisis 4000 55C(220 amps) at 655g has punch for short flight for 3D ...

The GensAce 4000 25C (100amps) at 658g jws39 Youtube Vid This battery is close to the factory max amps limit but for straight easy flying is great improving handling. CG may be a concern?

Batteries in this 650g weight range have been commented to be light that when as far forward as possible CG'd at 160mm which is tail heavy instead of the recommended 145-155mm. Several still successfully flew it in this configuration.

The Hyperion 4200 35C (147 amps) at 666g or the Hyperion 4200 45C (189 amps) at 674g Ref Colorado HeliNuts Vid

The Nano-Tech 4500 35C (175 amps) at 676g has a mixed rep.

The Genisis 4500 40C (180 amps) at 728g is very nice because its light and should still give a decent flight time but the more than needed amps capability is extra weight not being used.

The Genisis 4500 55C(247.5 amps) at 745g confirmed weight 728g posted weight. See Antaeus Vid Ref or Pete's flight from Banana Hobby

The Rhino 4900 25C (122.5 amps) at 730g -792g are a very nice fit for factory unless you intend to sit on the tail doing torque rolls. See Wargasms Vid Ref

The GenAce 5300 30c (159amps) at 752g - 765g See V8s Ref Vid Gold Motors

The Zippy FlightMax 5000 25c(125 amps) at 770g - 774g See SU4Ever's Ref Vid: Gold Motors

The Nano-Tech 5000 25C (150 amps) at 769g is still within the amps range and weight class. See Whiskey Whiskey's demo vid

The Gforce elite 5000mah 40c(200 amps) at 778g -741gSee V8 Vid performance.

The Nano-Tech 5000 35C (175 amps) at 786g has a mixed rep.

The Gforce elite 5000mah 60c(300 amps) at 788g -768g V8's Vid, V8's Vid onboard cam

The Genisis 5000 55C(275 amps) at 800g. More than the needed amps but this tends to guaranty less power drop off through out the flight. Temisn Vid

The Genisis 5000 65C(325 amps) at 805g. More than the needed amps and heavy for the capacity but performance will remain steady through out the flight.

The Turnigy 5000 30C (150 amps) at 805g. Please ref MIT_KID's flight vid with this battery using all standard setup as outlined in manual.

The Zippy 5000 40C(200 amps) 834g V8Truckin Maiden and Flight Vid

The Zippy 5800 30C (174 amps) 838g is great for long flight times as long as the pilot isn't WOT the entire flight.

The Genisis 5500 55C(302.5 amps) at 886g. Way more amps than necessary for the application.

The GenAce 5500 25C (137.5amps) 890g heavy without much amp/hr cap improvement.

The Nano-Tech 6000 25C (150 amps) at 908g tips the scales and still has a rep.

Where can I find Hyperions at a good price! Any others I should have a good look at?

Other Unknown Vid references.
Dick at Norton
Arecop13
gerysoelkner
Extremehobby Australia
V8s comparison flights of a GensAce5300/55C and a Zippy 5000/40C
Ooooppps That's the real thing
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Last edited by Maxthrottle; Mar 26, 2015 at 01:29 PM.
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