best quality batteries

[strodedawg]

hello,
i have a few questions some of you might be able to answer
my 1/8 crt conversion is done except for electronics choices, i have chosen between the following;

125b, neu 1515 1y/f, 14.8 lipo or
125b, neu 1515 2.5d/f, 18.5 lipo

my crt.t has
mamba maxx controller, 6900 motor, but what battery 2s or 3s battery?

my question is what brand of lipo, limn, a123 or other do you recommend for each. i have heard good and bad things about all of the cells available, but as the actual users and abusers of these products what do you recommend for batteries? any other comments are appreciated.
thanks
jim

As far as the CRT goes: You are going to get this answer alot, but go for two of the 2S trakpower 4900 batteries for a total of 4S. These batteries are extremeley powerful, and 4S is all you will need for your truggy. THese use the same cells as flightpower batteries, some of the best in the business. The quark is rated for 6S, but i think that people are having overheating issues on anything over 4S. I have two of the trakpowers on a LSP with a 8XL and it is uncontrolable. A123 cells are too heavy IMO. High quality Lipos are only unsafe if you try to destroy them. Link is www.duralitebatteries.com

Well, for the CRT, either configuration will get you about the same performance, since the 1y is a 2200 kv motor and the 2.5d is a 1700 kv motor; however, the setup with the 2.5d will draw fewer amps and run cooler (not that the setup will run hot with the 1y), at the expense of a bit more battery weight.

The problem is the controller. Some have had luck running the MM on 5S lipo, others haven't. It's a roll of the dice.

As for the smaller setup, the max I'd run on the 6900 is 2S. 3S will exceed the maximum rpms of the motor. I ran a 7700 on 3S and I couldn't gear it at all. The esc would just over heat. If speed is your concern, a MM with a 4600 motor on 4S would be the way to go, or even a 5700 on 3S. If you go with the 6900 on 3S, I think you'll have heat and gearing problems.

If you want the very best packs that money can buy, flightpowers and kokams are the way to go, in that order. Maxamps are good for the money, and I'm having good luck with the truerc 5S 8000mAh pack, which was dirt cheap, relatively speaking.

[squeeforever]

Personally, I would go for 5S for sure on the CRT. What packs depends on what kinda runtime you want. The Flightpowers are great batteries, but lack in the runtime. Yea, you can get a 2P setup, but there outrageously to expensive. I use TrueRC packs and like them very much. As for the CRT .5, go for 2S. Can't really say what pack because I don't know what will fit, but you might wanna look at the 2100HV packs from Maxamps.

[BrianG]

Hmm, so you think running 5Ah 2s pack in the CRT.5 is too much Squee? I like looooong runtimes. :)

[Serum]

and a chassis that's hanging to one side.. :)

[BrianG]

Actually, it should be balanced fairly well since the servo and motor is on the other side. It's just a 2s pack after all. :)

Sorry, didn't mean to hijack the thread...

[squeeforever]

No, I don't really. I like long runtimes as well. I just don't know the size limitations he has. The 2100HV packs should do alright I would imagine, but if you can fit a 5000mah pack in there, more power to ya!

[zeropointbug]

elegal, I wouldn't say A123's are too heavy, as 5s2p is lighter than NiMH, 720 grams total.

That's if you don't need anymore than 4600mah capacity. Keep in mind they are brand new chemistry, impressive none the least. (features more for full scale EV's)


So, in the end, if you want the best quality battery (I take it that's power), then yes like everyone is saying, the Trakpowers are at the top of the list, expensive.

[MetalMan]

Originally Posted by zeropointbug

elegal, I wouldn't say A123's are too heavy, as 5s2p is lighter than NiMH, 720 grams total.

That's if you don't need anymore than 4600mah capacity. Keep in mind they are brand new chemistry, impressive none the least. (features more for full scale EV's)


So, in the end, if you want the best quality battery (I take it that's power), then yes like everyone is saying, the Trakpowers are at the top of the list, expensive.

That 720grams is still lighter than 12 NiMh cells, but you get more power than 14 cells (5s2p A123). And comparitively the runtime is better.

[zeropointbug]

Does anyone have a full run of some LiPo packs with an Eagletree? I just would like to compare the Ah efficiency between standard LiPo and A123.

MetalMan, what's your runtime with your 5s2p pack running your 7XL. I will be running the same setup, just so we can compare. :p

As far as quality of packs goes, it depends on what you need too. If you are running a 4S setup and need a battery that can dump 100A continuously, then you need a true 20C pack at 5Ah capacity. On the other hand, if you are going with a higher voltage setup, the "quality" of the battery pack becomes less important. This was my reasoning behind going with 5S anyway.

I figured that if I was running a motor on 4S to achieve 30K rpms at a 100A constant draw, the running a motor on 5S to achieve 30K rpms should only take 80A under the same circumstances. That's what I'm figuring anyway.

On my truggy, I went from 4S with a 7XL to 5S with an 8XL and I think it runs a little better, but definitely cooler.

[overkill5000]

im running a hv maxx 4.5 on an emaxx i dont know much about lipo batteries... im trying to keep my truck as light as possible can i replace both of my regular 4200nimh 7.2batteries w/1 lipo?and will i need a balancer w/one lipo????

A 6 cell nimh pack is roughly equivalent to a 2S lipo pack. Are you running those packs in series? Ie., 14.4v? If you are, a 4S lipo pack would come close to that in voltage. Two 2S lipo packs run in series would do the trick too. Check out the maxx packs at maxamps.

[MetalMan]

Originally Posted by zeropointbug

MetalMan, what's your runtime with your 5s2p pack running your 7XL. I will be running the same setup, just so we can compare. :p

I think it's around 15mins., but I'm not entirely sure. I often change what I'm doing while driving (from run to run), so it's not really consisten. It also depends on the tires, since right now I'm running 1/8 buggy Road Rages and I would normally run Maxx Mashers (without changing gearing).