Weight ?

Hi,
What would be the difference in weight from a 6 cell 3300mAh NiMH pack & a 2 cell 3200mAh LiPo pack ?

Thanks for your help !!

Terry

[RC-Monster Mike]

The LiPo pack would weigh almost exactly half of the nimh.

Thanks Mike !
What other advantages would a LiPo Battery have over a NiMH Battery ?

I really do appresiate all the help you & the members give. Also I know the info I'm getting is very accurate because it is coming from very intelligent people, this site is priceless !

Terry

[RC-Monster Mike]

Well, bud, there are advantages and disadvantages. The Kokam LiPos can deliver more voltage as well as more voltage under load with around half the weight, so it makes a big impact on the power output (power to weight ratio is increased so the vehicle feels even more powerful). The LiPo batteries also have a potentially longer duty cycle then the nimh cells (in other words, they can last through many more charge/discharge cycles). The disadvantages are cost and danger (you must be careful not to harm the packs or you risk harming yourself!). Also, you must be careful not to overdischarge the packs(they may not come back after a deep discharge).

Thanks Mike,
Sounds like LiPo's are the to go ! Would it be worth the wait for the new LiPo's from FMA ? I think they were listed for $ 169.00 for 2 cell 3200, or will the Kokam from Tower hobbies work well ?

[RC-Monster Mike]

I use the Kokams without the saftety circuitry, but the new FMAs are probably the ones to go with. I am careful not to over discharge my packs, while the new Kokams from FMA take the thought out of it and automatically prevent over charge or overdischarge. I think the new ones are the way to go.

[JOHNNYMAXXIMA]

Anybody got a link to these FMAs?

johnnymaxxima,

www.fmadirect.com

Mike,
I still need a motor & controller for my XXX4 & getting tired of waiting for the LRP / Reedy combo ! I have 2 XXX4's one I have the Novak 5800 on 7 cells it runs strong, but I would like to use more volt's. I really don't think the LRP / Reedy will be all that much faster ?

Terry

[RC-Monster Mike]

The LRP will likely be faster, but it won't be able to take more voltage, most likely. If you want a high voltage system, the MGM or warrior controllers are the way to go. You should be able to fit 9 gp2200 cells in the stock battery space, which would allow pretty insane power. This battery setup with a lehner basic 4200 (or even 3600 or 3100) would give some serious performance.

I'm haveing a hard time finding GP 2200, The 2400 must be a little larger in dia. ?

[RC-Monster Mike]

I can get the cells for you if you want. LMK how many you need. You could also get them here:
http://cheapbatterypacks.com/main.as...gid=loosecells

Thoes GP 2200 seem very impressive ! How would I solider them to fit 9 cells in the space the XXX4 allows ?

GP 2200 =
Length : 1.32"
Diameter : 0.89"
0.89 x 9cells = 8.01"

GP 2000 =
Length : 1.68"
Diameter : 0.66"
0.66 x 9cells = 5.94"

The GP 2000 will fit fine side by side. I have about 6.12" to work with ?
They also have a 2500mah battery at 0.66" part # CBP2500A

Also how well would the Basic XL5000 work in the XXX4, using 9 NIMH batteries or 3 cell LiPo ?

[RC-Monster Mike]

You build an 8 cell stick pack with one cell laid across the other cells.

====! Like this. The fit will be tight, but I got them to fit my tc3 this way. The 2200 can handle much more power and have better energy density than the 2000s (more mah per oz)

Mike,
I have never built a stick pack ? LiPo 3 cell would be the way for me.
Do you stock Lipo's ? I'll start with one 3 cell pack along with a Lehner Motor I guess a Basic 4200 or 5000 & Controller, Astro charger. I'll send you an email soon.

Terry

[RC-Monster Mike]

I don't currently stock LiPo cells or chargers. I have given some thought to it, and I will no doubt stock them in the future, but for now, I don't(can't get a good enough price to justify carrying them).