Max Continuous for IB4200..

[aqwut]

You know, I never knew what are the Max continuous ratings for Sub C Cells.. anyone have any clue?...
GP3300, GP3700, GP4300?
IB3600, IB3800, IB4200?

I was thinking of getting some IB 4200's and putting together two 9 cell packs
my question is will those be able to be charged like regular packs since theyre more cells , ill be charging them on a duratrax twin pulse

[Serum]

The only ones that are rated for 100A are the GP3300's the 3700 have got a lower voltage on that kind of load.

The IB3800's seem to be good too, but they are not as durable as the 3300's, i've heard they are the best when charged at minimal 5A. the IB38000's are used in F5B planes where they deliver a 250A, i doubt if their voltage is above .4 V then.. the GP3300's should do about .95-1V @ 100A load, meaning they can deliver about 100 watts per cell.

With NIMH's or any 1.2V cell, the change there is an imbalance in the pack than with good 3.7V per cell lipo's.

If you want REAL current monsters, get the flightpowers.. Their 3300-5000 range of lipo cells can deliver higer currents your setup can handle..

they do a 250A in peak and stay above the 3V line. So with a 10S setup of the 5000mAh, they can deliver 7500 watts of peak power.

The maxxamps packs are great value for the money. a 5S2P pack of the 4000cells can deliver 27-2800 watts, and stay above the 3V per cell.

@maffia; yes, that should not be a problem. when the cells are equal (which is rather common with the nowadays production processes) or even matched, then you should be fine.

I always take a close look at the cells when i charge them for the first time. First time, you need to charge them with 1/10th-1/5th C (C is the capacity), and discharge them again with about 1C (4.2A in your case) then you can charge them with 1C (4.2A) and observe the cells when the charging process is nearing its end (after app. 45-50 minutes) check the individual temperature of each cell, if one cell stays remarkable cool or gets hot, the cells are not of the same quality (internal resistance) then you know you have got an imbalance in your pack.

[MetalMan]

The IB4200SHV cells might be able to handle 70amps continuously:
http://www.battlepack.com/testimages/IB4200SHV.jpg

[Serum]

this is more of a concern of these thing;

(from the same site)

IB4200SHV NIMH Sub C 66g 23mm by 43.0mm (zapped) IB cells can have soft shorting problems, no guarantee
(per cell)

[glassdoctor]

Here's a 70A discharge graph
http://www.rcgroups.com/forums/showp...3&postcount=19

It appears they would be good for 100A+ if they are warm... temperature of the battery is important jsut like lipos.

Check out this chart of GP3300 cells... at 45*C (115*F) to 60* (140*F) they do pretty well imo at 80-100A and the newer 4200 should be better than this.

http://www.rcgroups.com/forums/showp...3&postcount=19

[glassdoctor]

Oops I guess you guys have been busy in this thread. :)

[neweuser]

@emaxxmafia & guys-I thought pulse chargers were bad no matter what cells you have? He originally said a twin pulse charger? Anywho, putting together 9 cells should be fine, but make sure the cells don't have in balances when you first start charging and running them. i believe someone already said that..oops!

[aqwut]

Thanks!!! This was the stuff I was lookin' for...... EXCELLENT!!!!

[aqwut]

Hey Serum.. how could the Maxamps 5s2p 4000 Pack deliver 2700 watts?.. it's only rated at 60Amps Continuous and 80 Amps Peak...? that's only about 1500 watts right?

[coolhandcountry]

The 5s2p 4000 mah cells are accually 8000mah total. That would make it 120 amp continous and 160 on peak.

[aqwut]

Ah... thanks... I was think 2P of 2000 Mah.... Shoulda paid better attention....