blackjack brushless on lipos

[bwells]

Hello, joined today and have a question. I have a new blackjack that I want to run lipos in but I notice there is 2 deans for 2 batteries. Does the esc series these 2 batteries and does that mean I would need 2 lipos or do I make a wye to fake it out and only use one? I was looking at 5000MaH 11.1 burst 25 but 2 of them is a little pricey and if the esc series them, that's 22.2 volts which is more than I want to go. Also the 2 8.4 NiMH 4500 that I used once ( for my villian ex) would add up to 16.8 which seems okay but that is way more than an 11.1 lipo. I assume the amps released from the lipo offsets the voltage decrease. Hope I did this right. Thank you, Brian

[Jeff Wohlt]

Welcome! Yes you could make some adapter but then you just add resistance to the system. Not good. Just get two packs since the ESC has 2 power inputs.

You will want two packs of 2S to run that. Make sure you get 4000mah cells or better with at least 20C rating. Watch your CG at first and run it a bit heavier in front until you see where you are...then move them back as needed to get the nose up out of the water a bit under WOT. They like to flip and spin.

Also, be sure and program the ESC for LIPO. They make a program card for it but you can also do it with the TX...I would get the card.

[bwells]

thanks, I looked under the hatch and can plainly see that it is wired in series before going to the esc. One thought was to plug the lipo in one deans and the other one make a jumper. so you think it is better to have 2 smaller packs verses 1 large pack. with 2 can I go less MaH per unit and I have the programmer? 2 2s would give me 14.8 which sounds perfect. Thank you

[Jeff Wohlt]

I would not go lower in mah. You are still pulling 40-60 amps from the packs when in series. Yes, you could go with a 4S pack and make the ESC one connection wire but why. I would use two packs...gives you more flexibility later and you want the balance even in the hull.

That is a great motor in the BJ. I have sold many. It has excellent power all the way up to 6S. Much better built motor than most and has a nice cooling jacket already included. That is why it costs more too.

[bwells]

got it. I agree on the balance thing. so 2 2s 4000 Mah or better with a minimum 20c burst or continuous? I see alot of 15c out there but the 4000Mah with 25-30 burst are hard to find unless you go to hong kong with 4 to 6 week shipping. I guess it comes across the Pacific in a Chinese junk but by then the rats will have eaten the tin foil off! Thanks

[Jeff Wohlt]

rclipos.com. Elite cells. Have them in a few days for you. You want 20C or higher is better...see what the 25-30C diffeence is... they will last longer. Yes, 4000 or better.

You want a cells that has 80 amp continuous.

[bwells]

OK, there is a definate correlation to Mah to 20/30 and voltage. to get min of 80 amps continuous with a 7.4 I need a 25/35 4800. dropping to a 3300 25/35 gets me around 65 amps. I think I'm catching on and I thank you for your help, you pointed me in the right direction but what I need is 64 bucks a piece times 2! That's half the price of the boat but you got to do what you have to so I imagine I won"t go back to NiMH! Thanks again, Brian

[bwells]

One more thing on this. I found a 7.4 volt 4000mAh 4 cell pack config 2s2p with capacity 8000mAh 12c/24c cont 96 amp, burst 192 for 72 bucks. What is this and it sounds like 2 packs in one. Is this a gimmick? Thanks for your help, Brian

[ApacheDude]

I don't have personal experience with those cells but there are other packs that have higher output for a very similar cost. I would recommend the Elite cells from rclipos.com or cheapbatterypacks.com...

Other brands are good too, the Elites are the ones I went with.

You don't need to go overkill on the batteries, but definitely get something with high output and higher capacity. 25C and 4000mah+ is a very good rule.

[bwells]

Yeah, that's what I thought and that is what Jeff recommended so I will go with the elites. will these lipos give me twice the bang for the buck over NiMH?