samolot

My Feedback: (14)

IM interested in getting a new lipo, since i fried the first one. I am however curious about one thing, what is better, Cell count or mAh capacity? I have a choice of buying a 3 cell 3200 mAh battery or a 2 cell 6000 mAh battery: http://maxamps.com/index.html?lmd=38836.584491

Thanks

Samolot

guver

My Feedback: (325)

They are really 2 different things. For a given set-up the 3S will have more power because it is 50% higher voltage, yet the 6000 mah will have nearly twice the capacity. How about a 3S 6000 ?

samolot

My Feedback: (14)

Well, i was kinda looking at the price too, 140$ for 3 cell 3200mAh, or 80$ for 6000mAH 2cell

aeajr

My Feedback: (2)

Depends on what your motor and applicatoin require. You need to meet your voltage requirements or the MAh won't matter.

What does the motor call for? 11.1 V or 7.4V?

INeedHelp

My Feedback: (1)

Battery wieght may be a factor in your decision also depending on the plane in question.

aeajr

My Feedback: (2)

First thing you have to address is volts and amp supply, that is the ability of the pack to deliver the amps to the motor. Once you have met that requirement, THEN you can stat to think about how many MAh for duration.

perttime

What do you want to do with the battery?
What plane?
What motor?

samolot

My Feedback: (14)

Ok, here we go:

Ready To fly Tiger Moth from Hobby-Lobby: http://www.hobby-lobby.com/tigermoth.htm

Motor info:
AXI 2820/10

For 8 to 10 NiCad/NiMH cells or 3 to 4 Li-Poly cells, 11x8 to 13x8 props. RPM/V: 1200. Max current: 42A/60 sec., max efficiency current is 20 to 30 amps.

Hope it helps. I jsut want arelatively cheap battery to fly anywhere form 7-10 minutes

aeajr

My Feedback: (2)

The recommended battery is a 3 cell 3300 lipoly pack.

AXI 2820/10 is the motor - From Hobby Lobby description, - For 8 to 10 NiCad/NiMH cells or 3 to 4 Li-Poly cells, 11x8 to 13x8 props. RPM/V: 1200. Max current: 42A/60 sec., max efficiency current is 20 to 30 amps

That tells me 3 cell is minimum for this motor in Lithium.

The description says you will be flying most of the time at less then 1/2 trottle so you probably could fly on a 2 cell pack if you are looking for long gentle flights with little or now aerobatics involved. Otherwise you would be well advised to have a 3 cell pack. Your 2 call alternative will provide long flights, but potentially disappointing flights.

samolot

My Feedback: (14)

Aejr,

When you say potentially dissapointing flights, does that mean performance wise? Because this aircraft is jsut meant for long relaxing flights. I have my little arsenal of glow boys to do all the fun.

Samolot

PS: im not saying one is better than the other!! hehe

Tall Paul

I use 3 cell Lipos with my 2820/10. More than sufficient performance on relatively large heavy planes.

aeajr

My Feedback: (2)

Yes, performance wise. That's all.

samolot

My Feedback: (14)

I there a nimh battery with the same capacities as mentioned above? I only ask this because they are safer and cheaper.

Matt Kirsch

My Feedback: (21)

Cheaper? Yes, somewhat. Safer? With the cell balancing technology out there, the safety gap isn't quite as big as it used to be.

HEAVIER: That's what you have to worry about. The NiMH equivalent in voltage and capacity to a 3S, 3300mAh LiPoly is a 10-cell, 3300mAh Sub C NiMH pack. At 2.1 ounces per cell, plus wires, covering, and solder, you're looking at a pound and a half for a NiMH, while the LiPoly will weigh half as much.

aeajr

My Feedback: (2)

If you have been using NiMh packs and have charging equipment, you may opt for this route. If you have existing NiMh packs you can use, they may work fine. Looks like they will need to deliver about 30-35 amps at full throttle. Hobby Lobby can confirm.

Since your earlier posts indicate you are not looking for extreme performance, NiMh would be a very viable approach. The extra weight may not be of concern and may actually give you better windy day handling.

If you have Lithium charging equipment already then you choose your packs based on Voltage, then amperage requirements, then capacity. The recommendation being 3 cell, 3300 mah packs.

If you want to go Lithium and don't have equipment, then I suggest you call Hobby-Lobby and discuss this with them. As suggested by Matt Kirsch, you want a balancing charger and packs that have ballancing charge leads. This will give you the longest life, best charge and safest charge for your lithium packs. To buy a charger today that does not have balancing capability would be a mistake.

Finally, if you are not looking for ultimate performance, you could discuss a smaller motor. The write-up suggests that they plane cruises at less than 1/2 throttle. That give you lots of reserve for lost of performance, but you say that is not what your are looking for from this plane.

Goals and budget will dictate the best option, but only you can decide.

samolot

My Feedback: (14)

OK, I guess lipos are my only way out, if its lipos, does anyone know of any secret places where they sell lipos CHEAP!? THe only price i could find for a 3 cell 3200mAh is 130$.

Gigaah

http://www.commonsenserc.com/index.php?cPath=37_31

samolot

My Feedback: (14)

WOW, are those prices legal? Are you sure there is no hidden print behnd that price? Thats 50% off what i was expecting to pay. WOW, once again.

guver

My Feedback: (325)

I use Common Sense and they are great deals and great product.

aeajr

My Feedback: (2)

Samalot,

The only one there that would handle that motor would be the last one and it MIGHT be short on amp delivery. If you take it easy on the throttle or prop down a touch you would probably be OK.