Lipo Cell Configurations ~Confused~

[RotaryBoy]

Hello to all, :noteworthy

I'm brand new to Heli's and I'm reading like crazy trying to learn as much as possible.

I'm trying to understand the cell makeup and the charging methods of Lipo's, I have read they are very dangerous and must be treated very carefully.

My Heli came setup to run on 10.8V 650mah 9C NiMH packs, but it is Lipo ready. It is in the Micro size and I am currently running with 3s 11.1V 1000mah packs, I'm using a balancer and ensuring the cells stay steadily balanced and charged evenly.

What I don't understand......

I'm using a 3s pack (I know that is 3 cells in Series configuration)

I have found 3s1p packs (I know that is 3 cells in Series and 1 cell in parallel), these packs are 11.1V 1000mah packs. How does the extra cell in parallel affect the motor and ESC of the Heli?

Will the extra cell add flight time with my current setup?
The manufacturer's documentation says to only run 3S 800mah or 3S 1250mah in the Heli. Am I damaging the motor and ESC by running 1000mah packs?

Just trying to work through this now.... as I upgrade and move to a bigger heli... I'll already have a good understanding of the concepts...

RotaryBoy

[dna001]

I think you are reading it wrong...... 3s =11.1V but when fully charged it will be 12.6v

Have a read of this it explains it better ..

http://www.fmadirect.com/lipo_handbook/FMA_Lipo_Handbook_Section1.htm#Seriesconnectedcell s



.

[RotaryBoy]

Well, after reading through that writeup.... I think it is a bit more clear....

So... basically, a 3S1P that is 11.1V 1000mah is 3S 500mah X 2 (the 3 series cells are wired in Parellel to an additional 3 in series to double the mah output)

Right?

RotaryBoy

[Ruk1us]

My SuperBrain 989 just fried itself this morning. Melted the red banana plug and blister my finger when I went to giggle it. I have read/heard good and bad about this charger. Is there a charger out there that is highly rated for these packs?

[marchambault]

A 3s1p pack is 3 cells wired in series.

A 3s2p pack would be 2 banks of 3 cells, wired in parallel. This would still give the same nominal voltage (11.1V) but double the mah capacity. Essentially, two 3s1p packs wired in parallel, thus 3s2p.

[helicraze]

3S1P 11.1V 1000MA is 3 1000MA cells wired in series.

[dna001]

Wire the cells in series and add the volts together, the mah stays the same
Wire the cells parallel and add the mah together, the volts stay the same

[Pinecone]

3S and 3S1P are the same thing. If P is not specified, it is 1.

In most cases, you don't care about P, just S (voltage) and total capacity.

[JEB123]

Like Pinecone said, it's the same. To get the number of cells multiply the S by the P. 3S2P is 3X2 or 6 cells, or 3 in series in parallel with another group of 3 in series. 3S1P is 3X1 which is 3 cells in series. Period. There is no extra parallel cell. As long as the voltage is correct, you can have a billion mAh, the motor (or load) will only draw what it requires to operate, you will just get longer flight times and more weight! :thumbup:

[SonGunnar]

Hey dna,

You seem to have knowlegde in this area . . . and I am floundering

1. I have a 70 Amp, 2-4 Cell lipo Scorpion ESC, and a Scorpion HK3026 motor, 1210 KV.

Can anyone tell me if (2) 4, Cell, battery packs were run in parallel, would the 4 Cell ESC, recognize the combo as 4 Cells?

I would think operating time should go up, if the esc would work.

2. Will the motor and esc work with (1) Zippy 2500 or 3500 Pack without cooking the works (maybe governor mode set by ESC)?

The Heli I am looking at is rated for 6 cells 1200 kv but is sold with 6 cells 1100 kv, so I think I have some latitude..

I am thinking that weight savings may justify a higher pack rating, with lower cell count, but worried about amp burst rates?

Thanks - SG

[helicraze]

If you run (2) 4 cell packs in parralell it is still 4 cell as far as the ESC is concerned. The voltage is the same.

[dna001]

Hey dna,

You seem to have knowlegde in this area . . . and I am floundering

1. I have a 70 Amp, 2-4 Cell lipo Scorpion ESC, and a Scorpion HK3026 motor, 1210 KV.

Can anyone tell me if (2) 4, Cell, battery packs were run in parallel, would the 4 Cell ESC, recognize the combo as 4 Cells?

I would think operating time should go up, if the esc would work.

2. Will the motor and esc work with (1) Zippy 2500 or 3500 Pack without cooking the works (maybe governor mode set by ESC)?

The Heli I am looking at is rated for 6 cells 1200 kv but is sold with 6 cells 1100 kv, so I think I have some latitude..

I am thinking that weight savings may justify a higher pack rating, with lower cell count, but worried about amp burst rates?

Thanks - SG



Two cells in parallel = same voltage, now add mah together, operating time would go up but remember you are now adding weight, more weight less operating time.

how many cells are in the zippys,
If your ECS is rated for up to 4 cells, then it will only take 4 cells, If it is rated for 6, then 6 is the max. 4 cell = 18v and 6 cell = 25v.

By a higher pack rating, do you mean C ratting

C ratting = Amp bust rates , For example, lets say you are pulling 60A constant, (just an example )
60A from 4 cells is not as efficient as 6 cells.
less efficient = heat, heat = not good :-)






.

[SonGunnar]

If you run (2) 4 cell packs in parralell it is still 4 cell as far as the ESC is concerned. The voltage is the same.
Helicraze,

Thanks for the response ... sounds like It could be done but the voltage would probably be too much.

SG -

[SonGunnar]

Two cells in parallel = same voltage, now add mah together, operating time would go up but remember you are now adding weight, more weight less operating time.

how many cells are in the zippys,
If your ECS is rated for up to 4 cells, then it will only take 4 cells, If it is rated for 6, then 6 is the max. 4 cell = 18v and 6 cell = 25v.

By a higher pack rating, do you mean C ratting

C ratting = Amp bust rates , For example, lets say you are pulling 60A constant, (just an example )
60A from 4 cells is not as efficient as 6 cells.
less efficient = heat, heat = not good :-)






.
dna001,

Thanks for the reply.

I was under the impression that c rates were a rating system for amp bursts?

But it looks as though I need to purchase a 100A ESC, 6 cell charger, and 6 cell battery(ies).

Anyone looking for a new 70 A scorpian esc? ->

- SG

[JEB123]

C stands for capacity and is the discharge rating.10C means 10 times the capacity of the battery pack. If there is a burst rating usually it will show it second, as in 15C-25C. Check this out:
http://www.ampaviators.com/index.php?option=com_content&task=view&id=48&Itemid=27

[SonGunnar]

C stands for capacity and is the discharge rating.10C means 10 times the capacity of the battery pack. If there is a burst rating usually it will show it second, as in 15C-25C. Check this out:
http://www.ampaviators.com/index.php?option=com_content&task=view&id=48&Itemid=27
JEB123,

Thanks for the link. Sometimes we can search for hours for bits and pieces of needed info.

Makes me want to give back .... hmmm .... maybe an article on everything that can be done wrong ;~>