mrbeesboy

Hello all,
The E-flite J-3 cub 25 i'm building calls out for ThunderPower4200 3S2P, 11.1v Li-Po, 13 GA , battery. I don't want to spend $125 dollars for a battery. Does anybody out there know of some different brands that are a lot cheaper? I was looking at turnigy however the closest i've found is 4500mah and most are 1P. I'm assuming this battery would be fine, but I would have less flying time. They don't tell me if they are 13 gauge wire or not. I just want to make sure that the battery I buy is equivalent to the one that's called out.
I'm still learning and doing a lot of internet reading. Yes....i'm a newbie!!!
I appreciate any help with this.
Thanks

Glacier Girl

My Feedback: (4)

Well I flew mine on a pair of 3S2100 packs wired in parallel. Gives you the same voltage and capacity as the 3S4200 single pack.

The TP as a 3S2p would mean the pack is made up of 6 cells wired in a parallel/series arraignment.
Would be 2 sets of three 1S2100 cells series wired to give you a pair of 11.1 volt packs, then the two packs are parallel wired together to give you the 4200 mAh.

And looking at the TP pack I count 6 cells in it.

You gotta be careful when reading, I just looked that pack up on Amazon. Header states 11.1 volts (which is correct nominal voltage) but down below in the ad is says the voltage is 14.8!
NEVER GOING TO HAPPEN. A fully charged 3S pack, no matter it's capacity is 12.6 volts. 14.8 volts is a 4S pack voltage!
http://www.amazon.co.uk/Thunder-Powe.../dp/B000PBYVTU


Anywho, the packs you found listed as 1P just means they are using THREE 4200 mAh cells to do the same thing as TP is doing with 6 2100 mAh cells. Same 11.1 volts, same 4200 mAh.

Will do the same job equally.

And like I said in the beginning, I used a pair of 3S2100's to run mine. Same voltage and mAh when wired in parallel, as the TP single pack.

I used the old 3S2100 20C packs from Hobby King, you can get a pair of the 3S2200 20 C packs for what 16 bucks plus shipping now. An extra 200 mAh over the TP.
Even if they don't hold up as well as the TP, you could buy 14 packs including shipping, for the price of the TP pack.

As an added side, all those 3S2200 packs could be used in various series/parallel connections to run a whole slew of different planes. The TP is going to have to only be used in a bigger craft that can carry all that weight.

For a long long time that's all I ran, probably had a dozen of em. Just changed the hook ups to up the voltage or capacity as needed. And I could fly multiple planes, one right after the other, rather then one plane one time and then sit around waiting for the pack to recharge.


As for the gauge of wires, packs like the 2200 or even the 4200 from HK use 12 gauge wire, heavier amp capacity then a 13 gauge wire.
Once you get up into the bigger packs, they go to 10 or even 8 gauge wire on them.

mrbeesboy

Thank you for your response! You've cleared up a lot of questions I had. I'm going to copy and save your reply for future reference. Once again, thank you for your help!!!

Glacier Girl

My Feedback: (4)

You're quite welcome.

Rather have someone ask first and me explain, they to have em do first and then I get to explain.

Remember there is no such thing as a "stupid" question.

Have fun with the Cub!

mrbeesboy

I found Turnigy 3S 2200 20C's for $10.99 a piece + tax. Well, since you really impressed me about your knowledge, I have another question for ya...  I will try not to keep bugging you, but the last piece of this puzzle that I don't have, is a good charger for these batteries. If I have to pay $90 bucks or so, that's ok. I've looked online a lot, but there are so many to choose from. I want a real good safe charger and hopefully one that can plug in to your average 110 and also be able to hook up to 12v on the field. Keep in mind, I will be writing all the info in my book where not to repeat questions. Thanks again in advance!

Glacier Girl

My Feedback: (4)

Let me do a little checking for you.

Mine are ancient Astro 109's, great charger but does not balance charge. You have to plug in a separate balancer on them.

Mine are both 12V units. In the shop I run both off an old PC power supply.

Glacier Girl

My Feedback: (4)

Here's a good pair, though both are 12 volt units.


http://www.hobbyking.com/hobbyking/s..._GENUINE_.html


http://www.hobbyking.com/hobbyking/s...5FCharger.html