Green Power LiPo batteries

[rufus]

I have a quick question, it wasn't worth making a new thread. On a 500 class heli, when you normally use a 22.2v lipo, is it possible to use two 11.1v lipos? it's kinda cheaper, and I notice that on the ads for 11.1 it says for 450/500 heli.

Thanks,
rufus

[MikeK1981]

I know on the trucks that the ESC needs to be capable of handling the voltage of running two batts in series.  The 500 should be able to handle that since that is what it is designed for but you would have to get special wiring to hook the batts together at the least.  Plus I would imagine this would be heavier than running one 22.2V.  Feel free to correct me if I'm wrong, I'm pretty new to all this electricity business LOL.

[rufus]

I found this: http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXYHX5&P=FR

[MikeK1981]

That is what I was refering to.  I think this should work, but why are you wanting to do it exactly?

[15Crewdawg]

The Hurricane 550 uses 2 3S batts in series or a 6S. Other than the issue of mounting 2 batts and wiring, it should work as a 6S. I don't see the hurricane using a special ESC, so I would assume it would work fine.

I think the biggest issue would be the mah.

Any ideas why it wouldn't?

[rufus]

The Hurricane 550 uses 2 3S batts in series or a 6S. Other than the issue of mounting 2 batts and wiring, it should work as a 6S. I don't see the hurricane using a special ESC, so I would assume it would work fine.

I think the biggest issue would be the mah.

Any ideas why it wouldn't?

I was thinking about it... why wouldn't it work? Think about it... a 22.2v lipo is 6 cells together in one pack. A 11.1v lipo is 3. Put them together, the cells are physically the same size, so the weight should be somewhat the same. I have no idea why 22.2v are so expensive

[15Crewdawg]

Me either. Only thing I can think is maybe it's more difficult to cell match 6 cells than 3.

Maybe some other guys with more knowledge of LIPO's will jump in and explain.

[MikeK1981]

Me either. Only thing I can think is maybe it's more difficult to cell match 6 cells than 3.

Maybe some other guys with more knowledge of LIPO's will jump in and explain.

That makes sense to me about the manufacturing aspect.  Also 3 cells might be more common so when they produce them in large numbers that also brings the price down.  OK now I see, your doing this to be cost effective.    Your right, it probably will weigh about the same.

[kloner]

I have a quick question, it wasn't worth making a new thread. On a 500 class heli, when you normally use a 22.2v lipo, is it possible to use two 11.1v lipos? it's kinda cheaper, and I notice that on the ads for 11.1 it says for 450/500 heli.

Thanks,
rufus

Absolutley. 450 uses one, 500 uses 2, they work on both. It actualy isn't that bad. I put one up under the battery tray and one on top of the tray and i strap that down with the velcro strap as well as i'm running velcro on the tray and batts to keep them where i put them.

It is a lot cheaper and yes, i'm sure it has to do with volume of sales. Lots of 3s uses, very little for the rest. I typicaly do just like what the tower link above shows, but i just do that at the end of the esc input wires. the negative goes on the negative of one plug, positive goes on the end of another deans plug then you solder a wire from  the negative of one plug to the positive on the other plug. Same thing posted, but no female conector in front of it. The Deans plugs have a limit starting at amperage approaching 80 amps, that is where a 500 class heli sits. by running 2 seperate batts wired like this, your good to 100 amps +

[bad007]

Two 3s pac's in series is what I have thinking about also and was going to start a topic. Turnigy 2650 6s 30c aprox weight is 565g, and 2- 2200 3s 30c are 255g each adding up to 510g. So how about the weight differance, could it be the 11.1 packs have lighter straps joining the cells together? We all see the higher weight with higher c rating due to heavier wirring and could it be not just the  wirring and lighter straps joining the cells together? It's a bummer to toss a 6s pack because one cell crapped out.

[MikeK1981]

That is another good point, if you lose one cell you only have to throw away a 3 cell battery instead of a more expensive 6 cell.

[kloner]

I am also pretty sure that when you run 2 25c packs, your getting 50c of flow when in series. My 500 motor draws 80 amps and i've never seen heat even in the lipos. My 450 draws 50 amps and with one pack can get warm from time to time. I am right on the line

[Gerard]

Two 3s pac's in series is what I have thinking about also and was going to start a topic. Turnigy 2650 6s 30c aprox weight is 565g, and 2- 2200 3s 30c are 255g each adding up to 510g. So how about the weight differance, could it be the 11.1 packs have lighter straps joining the cells together? We all see the higher weight with higher c rating due to heavier wirring and could it be not just the  wirring and lighter straps joining the cells together? It's a bummer to toss a 6s pack because one cell crapped out.

Not to spilt hairs, but the Turnigy 2650 30c is 466g, according to H O B B Y K I N G.

[bad007]

Two 3s pac's in series is what I have thinking about also and was going to start a topic. Turnigy 2650 6s 30c aprox weight is 565g, and 2- 2200 3s 30c are 255g each adding up to 510g. So how about the weight differance, could it be the 11.1 packs have lighter straps joining the cells together? We all see the higher weight with higher c rating due to heavier wirring and could it be not just the  wirring and lighter straps joining the cells together? It's a bummer to toss a 6s pack because one cell crapped out.

Not to spilt hairs, but the Turnigy 2650 30c is 466g, according to H O B B Y K I N G.

How many cells is the 2650 30c bar you saw , I didn't see anything that heavy unless it was 6 cells

[bad007]

I am also pretty sure that when you run 2 25c packs, your getting 50c of flow when in series. My 500 motor draws 80 amps and i've never seen heat even in the lipos. My 450 draws 50 amps and with one pack can get warm from time to time. I am right on the line

I don't know about that in series thing boubleing the c rating. I think in sieries you double the volts and keep the 25 c rating and in parallel it should double the c rating and volts would stay the same. The cells are in series in the pack meaning all the curant has to flow threw all the cells and straps joining them together. Your kinda saying that one 12 gauge,15 amp, 25 foot extension cord would handle 15 amps and two plugged together end to end would handle 30.