2600? Sub C or C? The only GP's I'm farmilar with that are 2600 are AA size, which I somehow doubt can do 100 amps :)

me too, lol, i do not know what the heck is going on here lol. So guys, just tell me which batteries i should roll with. gp3300?

ibc 3800s. no doubt.

how much biggeer are they? Are they longer or jsut bigger in diameter?

The IB3800 cells are the same size (give or take half a mm) as GP3300's as they are cells designed for RC use. They're your safest bet unless you want to sink a bit more $$ into the GP3700's, which may or may not be better.

I just had contact with BK over this issue, they also sell the IB3800's, and they claim that the GP3700 is the best for the highamp MT trucks..

The GP3300 is a great cell, it kept the highest voltage on a heavy load (100A) one cell is able to give a rough 100 watts. (voltage @ 100A is about 1V, which is pretty amazing for those absurd high amps.) according to the information BK gave me, the GP3700 would be a tad better. those IB3800's are not recomended for 70A + applications.

And according to Mike's experiences, the IB3800 has got a bit more punch.

I'm going to get a new set GP3300's and those IB3800's.. (the 3700's don't seem to fit the gmaxx chassis)

I should get me an eagletree data recorder.. I'll warm up my girl for one..

@awqut, what cells did you use with you former setup?? you need to know that a BL setup can't be any stronger than the power your cells can produce! a 16 cell setup can't deliver more than 1600 watts (with perfect cells that is)

so ibc3800's are better perfroming then gp3300?

No, according to BK, the 3300's are 100A rated, and the IB3800's 70A.. With a rather hot setup (7XL on 18 cells) it will for sure take more than 70A!

i am so confused on which cells to get, 3300 or ibc 3800? I AM CONFUSED :s

You can't really go wrong with either. Look at it this way, the 3300 will give you maybe slightly more power because the higher peak amp draw, the 3800 will give you more runtime, and be more punchy for longer because the extra capacity.

Find a price on your batteries and let that help as well toby. I like the gp 3300 and the gp 3700. I do seem to get a little more out the 3700 as far as punch and run time. The gp 3300 is a good batery. I have never tried a ibc 3600 and 3800.

My former setup was Dual brushless with 18 cells(36 cells) each... and 24 cells each (48 cells)

I was thinking of gettin' two 22.2Volt 8000 mah, lithium cells.. (12C) 96 Amps continuous.. which is roughly 2100 watts.. but I'm gettin' two packs.. so I guess that's over 4000 watts of battery juice.. Should be good for my 2280.. I want full power... Nothin' goin' to slow me down but a tree or parked car.. hahahaa

Robotcombat sells GP 2600 Sub C's... they rate it at 80 amps continuous.. 3300's are 45Amps continuous....

The Sanyo C's are also 80 amps continuos.. both the 3000mah and the 3600mah...

I'm gonna get some of those GP2600 sub C's....

I'm pretty sure the guys at robotcombat knows their sh*t.. :) ALways learing something new in the RC world..

Well if price is a problem toby.. just buy Loose unmatched GP3300s.... can you guys really tell the diff between matched and unmatched packs... I really can't tell the difference, but the price... :)

I remember I had these really cheap $$$$ GP3300 unmatched rainbow packs, which I bought from ebay..

I got three 6 cell stick packs for $100 shipped from hong kong back then.. and they performed just as well as my FineDesign Packs... but half the cost..

I can see a little bit of difference. If I was to race matched, not racing a good deal on good batteries matched or not.

Thing is matched batteries give you only a small bit more punch, but they keep giving it till the battery gets very close to dumping, unmatched cells will start to drop off eariler. I notice this in the last couple of laps racing my truck (GP3300 cells).

Unless you discharge/equalise your cells after every couple of runs they'll be unmatched by the time you've used them 50 times, bear that in mind.

Yes, once every 10-20 times of use, give them a 1/10th C and 1C 2-3 cycle treatment! they will thank you for that!

I don't really do that..I just fast discharge mine after every run to 0.9v/cell, and equalise all the cells just before recharging every 3-4 runs. My 8 cell packs are taking in ~4000Mah and peaking at around 12.2-12.3V, so can't be that bad. Coming off the charger around 40-45C which is fine.

How do you discharge them at .9 volts per cell? or is it 8 times .9= 7.2 volts? or do you really equalize them with .9 volts per cell? and how do you get 1.5+ volts in your cells?

When the charger peaks on the cells each cell is approx 1.52-1.53v (using a 4mV/cell delta peak cutoff).

I have an old Mtroniks 10 amp discharge device that does 4-8 cells, I set it to discharge to 7.2v for an 8 cell pack.

I use a discharge tray (LRP Concept) to equalise the cells down to 0.6v/cell. This is a 6 cell tray so I do 6, then move the cells up 2 and do the remaining two. I use a Novak Millenium as a charger with a Pro-Peak 13.8v/20 amp power supply.

And do you find an unbalance in discharging? with a 7.2 V discharge and an unblance, you might also drain a cell lower than the .6 volts

Fast discharging at 10 amps down to 0.9v/cell doesn't actually bring the nominal voltage that low. A cells voltage may be 0.9v at 10 amps, but at 2 amps its closer to 1.1v. I have had no problems or unbalanced packs using this method for several months now on both matched and unmatched/very low packs. In the UK this is the most common method of looking after cells when racing I have observed, the biggest variation is if you equalise after fast discharge, or just before recharging, I do it just before recharging.

Contrary to what a lot of people say, you can take NIMH's below 0.5v/cell or even dead short them, if you start doing it while they're new, otherwise they don't take to it well. Doing this shortens their life and runtime but does give a noticable increase in punch.

If the cells were that unbalanced that one cell can be 0.9v and another 0.2v causing damage the packs not likely to be any good anyway. I personally haven't seen this much variance in cells even on packs that have been abused on a pulse charger for over a year.

Okay, thanks for that info!

The method you are using (staying above .5 volts each cell) doesn't affect the capacity nor it's lifespan? that .6 volt discharger simple are a few diodes i presume? You could easely make it yourself! Guess i'm in the race for some serious resistors to discharge a 16-20 cell pack with 10A... only downside is that you need to replace the heatshrink more often..

No problem mate.

Discharging to 0.6v/cell is perfect and doesn't affect the capacity nor the lifespan. The tray I use does indeed use a diode with a resistor, and some bits for an LED to tell you when its done. Easily made, check out http://www.schumacher.clara.net/equaliser.htm for a basic diagram, and a link on how to add status led's to it.

I've never needed to replace the heatshrink on my cells due to charging/discharging, I don't understand why you'd need to? As your only going to 0.9v with 10 amps you aren't heating the cells that much, and most tray's to equalise at 0.6v start at 3 amp and get lower the lower the voltage goes, so doesn't make the cells more than warm.

EDIT: Unless you mean pack heatshrink, I was referring to cell heatshrink, I never use pack heatshrink anyway and just run some tape around the middle of the cells and a bit of glue between each cell to hold the packs together. I have yet to short out a pack in a car doing this, you just have to be careful.

Yeah, that edit was what i was talking about. ;)

I will make one of those things, i thought they are forbidden for nimhs and they are meant for nicd's, i will try it for sure! (one of the myths about nimh i think)

Only need to find a nifty way to discharge the cells at 10-11A and make a cutoff at the desired voltage. Can't be that hard..

Its a myth that you can't use a tray with NIMH's. You shouldn't use NiCD trays with NIMH's because NiCd ones cut off a lot lower which will harm NIMH's.

Some people use a series of lightbulbs with a diode to cut off as a fast discharger, make sure you put a cut off in place if you do that though as if you take a NIMH to 0.6v at 10 amps you may harm it.