4wd electric

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Old 03-14-2007, 07:29 AM
  #91  
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ok, thanks. That's good to know. So I guess I need to have the lipo in a non flammable container during a charge. From what I am hearing, it seems like that is a mandatory precaution.
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Old 03-14-2007, 08:34 AM
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1C is equilvalent to exactly what charge Amp rating?

So for that 8000mah pack, you are saying that you use the same pack in two vehicles, and other than repeaking, can run it all is that correct?

How is the weight of the 8000mah pack compared to a IB3800 or equivalent pack?
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Old 03-14-2007, 08:44 AM
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Originally Posted by Cain
1C is equilvalent to exactly what charge Amp rating?
Alltapdout said that it depends on the Mah of the battery. Seems like if you divide 1000 from your lipo battery Mah rating, you get your recharge amp rate.

8000Mah lipo = 8amp charge rate
4400mah lipo = 4.4amp charge rate.

That's what I am getting from his post anyway.
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Old 03-14-2007, 08:48 AM
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Thats what i am thinking too.

That pyrex dish and sand thing doesn't sound like a bad thing to do, and really isn't too involved either. Heck, would say me the trouble of bringing the discharger along and other normal battery voodoo .

So what seems to be popular with the lipo 4wd crowd for mah size for the stick pack style lipos?

Also, if you are using maxamps ones, is everyone going with the stock setup of the wires or getting them coming out of the top?

Is balancing really necessary?
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Old 03-14-2007, 09:06 AM
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yes... 1c for an 8000pack is 8 amps.

Remeber we refer to batteries in "mah" but you can also call them by "ah" amp-hour

"8000" packs are 8ah packs.... 4400s are 4.4ah packs

That makes it much easier to see what "c" is... 1c is 1x the capacity 8 amps and 4.4 amps.

2c would be 16 amps/8.8 amps for these packs, etc....
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Old 03-14-2007, 09:12 AM
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I would recomend the 'liposac' things for charging and storage, along with a fireproff container of some sort... metal can or box etc.

BBQ grills... pyrex... clay pots... etc also work but are not cool to bring to the track

If I had a single pack car... I would do around 5000-8000mah packs. Depending on how much weight you want to shed... too light can be a bad thing.

Remeber too that the bigger the pack the faster the recharge time after a race. You will use the same amount of juice per run, but you charge big packs at higher amps. A full charge will take the same amount of time of course... @ an hour.
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Old 03-14-2007, 09:17 AM
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Thanks for the info. Not too worried about being cool now that I am married :lol .

Do you feel the extra cost of the 8000mah versus the 6000mah is worth it? Also, anyone know what an average nimh GP3300 or better pack runs weight wise?

Trying to compare everything.
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Old 03-14-2007, 11:24 AM
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I was being sarcastic about the precautions and charging actions with lipo's. I actually have a maxamps 2100mah 11.1v battery sitting here that I've been contimplating on using, but I haven't read up on if the GTB's can handle them or not.

My brother uses nothing but lipo's and I've seen the difference of run times, but I will say that I get a good 20min. or more with my 4200's I bought from maxamps with all my brushless systems.
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Old 03-14-2007, 03:47 PM
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Yeah Corey, I did find it humorous you used one battery for three heats and a main last Saturday

Luckily, there was plenty of time between heats!
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Old 03-14-2007, 05:19 PM
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Cory!!! Unfortunitly the novak brushless GTB is only rated at 6 cells...I called novak to confirm this since when a lipo pack is fully charged it is 8 volts..They said that this is not a problem.. Do not try to place a 3S pack on the GTB!! just fair warning.. As far as battery size... I have a 8000 mah battery.. Very few times have I run the battery down all at once. My car usually brakes or something it seems...I personly like the 6000, it seems like a good compromise to me.. Also the larger capacity batteries usually have a higher discharge current!! = More power.

orion also makes a very nice lipo battery 4800mah. comes in its own metal case..which is nice. But after finding maxamps.com on the internet. that changed everything! The 8000mah battery is very close to the same size as a normal 6 cell stick pack.. There are all the specs. on sizes on there web site.

Also I am not sure how much a 3300 pack weights, but i would say that a 6000mah lipo pack probably weights less!

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Old 03-14-2007, 06:49 PM
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Someone told me the 5000mah pack had better rating than the 6000mah pack from max amps, but I am not sure exactly what they meant? can someone elaborate?

Got my mamba max on the way. Wish it did a full 6V bec, but for the price its a small compromise.
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Old 03-14-2007, 07:39 PM
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I meant that the 5000 cell is a newer better cell than the 3000 cells that are used in to make the 6000 pack. The new cells have better voltage, basicly... but the 6000s are very close. The 8000s hold voltage a bit better than both cause it's the big boy.

Weights....

nimh 6 cell pack... 13-14oz

Maxamps:
8000 pack... 12.9oz
6000 pack... 10.5oz
5000 pack... 8oz
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Old 03-14-2007, 09:06 PM
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aggdaddy- I recommend you get an 8000 man, you will LOVE it. As long as you car isn's designed for saddle packs go for it.

I believe you said you have a Duratrax ICE. That is what I use. Set it to 8amp charge rate and have fun.

lipo is not as big of a deal from a saftey standpoint as some make it out to be. You just have to be responsible and keep an eye on the pack. Even in the videos where people intentiionally overcharge or short lipos, I've never seen one just combust without plenty of warning. Having some sort of charge/fire containment is nice but I admit I don't. I just have an extinguisher handy at home and the track. I do store them in an ammo can though at home. There is a very large group in my area of over 30 using lipo in racing every week for several years now. NO fires yet. I've got hours upon hours upon hours of lipo runtime in, enough to wear out 50 NiMhs, and no problems at all.

Probably the biggest scare I've had: I was running my B4 in practice at the track last year and the car stopped and started BOILING smoke. I thought "great, I'm going to be the first one with a lipo fire". Turned out to be the ESC.
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Old 03-14-2007, 09:27 PM
  #104  
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I have the BJ4. I haven't seen any 8000Mah saddle packs.
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Old 03-14-2007, 09:41 PM
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Oops. Well the Maxamps saddles would probably be the way to go then. Good luck with whatever you get. I'm all for showing up the nitros.
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