Desert Toad

I know this has been convered a hundred times before, but so many choices have my mind spinning.

I've finished building the KMP September Fury model, and have installed JR digital servos. I know I need a bigger battery for this, perhaps 1400 or 2000. But with NiCad and MiMH, I'm not sure which would be best, and what can I charge with my standard charger, and what needs a different charger?

Thanks!

jetmech05

The bigger the battery the more charge current or more charge time you need......If your going to stay in the hobby and get bigger airplanes and batteries get a bigger charger...I have 3 turnigy chargers...they have served me well.......
As far as which is better Nicad or Nickle metal...eh.....it's voltage and capacity that count.......if you don't like to charge get LI-Ion or LiFe batteries...more expensive...longer to charge..well need a voltage regulator...and a bigger better charger....and they need a litlle more attention when charging...but you only charge once a month or 6 weeks.....
6V over 4.8V will make your servos stronger and faster...some servos don't like 6V....my first retract servos didn't......

jester_s1

The good news is that computerized chargers for NiCds and Nimh batteries are super cheap on the used market these days. I saw an original Triton for $30 recently, which is a very well made unit (also does Lipo's with an additional balancer).

Pylonracr

There is one more factor to consider. Lithium batteries, even with the regulator, weigh about half of what the equivalent capacity nicd weighs.

Desert Toad

thanks for all the info everyone. I'm not worried about weight, even with an O.S. 1.60 on the nose it's a bit tail heavy. I'm just looking for a battery that will give me half a dozen flights now and then, and wouldn't require me to buy a separate charger.

scale only 4 me

My Feedback: (158)

The question is really hard to answer with the limited info you've given,,
5-6 flights of what duration?
If you're using all digital servos that reduces flight time?
How many servos?
electric retract?

See to many variables to consider

But to answer part of your question
A 2000-2600 mah NimH packs can be charged with standard wall chargers,, I do it all the time, and they can be topped off at the field with very inexpensive field chargers if you choose to buy one,, Other wise watch the volts with a load testing type

Based on what I've read so far,, a NimH 2600 would do you fine,, I have a single 2600 5 cell in my 16lb, 70" span Ziroli P-47,, I get at least 4-5 10 minute flights per charge,, and that's with running Lado electric retracts and some but not all digital servos

good luck

Desert Toad

The 2600 NiMH sounds like a perfect fit, I'm running 6 digital servos, plus standards for the air retracts and throttle.

Where did you buy your battery packs?

Thanks

scale only 4 me

My Feedback: (158)

Actually I looked it up and they are black label 6V 2300mAh NI-MH AA packs (not 2600 after all), I bought from an Ebay vendor, I'm not going to name them,, they aren't selling the packs now anyway,, I checked

They look like these http://www.ebay.com/itm/6V-2300mAh-N...item1c1e26a836


Funny thing is I paid more than double for a couple Hydrimax 2000 4 cell packs from tower and one of those is dead after only a year,, while the cheap packs are still going strong. In defense of the Hydrimax pack,,I think I may have left it on and drained it too low,, not sure.

Good luck

TEBerg

My Feedback: (1)

I just wanted to add a quick note since I just went through pretty much the same thing...

When you get your new 2600 pack, you still need to condition it - the first charges are important to the performance and life of a battery. Please do a search and you can find a lot of articles. Radical RC also posts a lot of information.

You will need to "trickle" charge the pack at 1/10 its capacity (C) for about 15 hours the first charge. Meaning that a 2600 mAh battery will need to be charged at 260 milliamps (250 is close enough) for 1-1/2 times its total capacity. The extra 50% pushed into the battery is to overcome chemistry and heat loss during charging. (OK battery guys, this is a simple explanation and don't kill me on the small details)

This is important for two reasons - #1 you should NEVER use a Peak Charger to condition your new battery packs. There is a lot of info out there that NiMH batteries do not work well or at all if you try this. #2 although you CAN use a “wall wart” charger for these bigger batteries (especially if you only flew one flight and are just topping off the battery before the next use/day), it WILL NOT be a good way to condition your battery because most are only 60-100 milliamps from the manufacturer. This is not enough to get the battery chemistry working right.

So, what I use is a multi-charger that has selectable charge rates from 50 up to 500 milliamps on SLOW CHARGE, not peak charging. After a few uses/cycles, it is fine to charge overnight and peak charge in the field…

Just my thoughts…

SCOTCH19

can ya tell me the make & model of your charger,,,would it be a good start into the edf jet equipment,,I'm just trying to tool up for my transformation from nitro to edf,,

TEBerg

My Feedback: (1)

Scotch, I don't think the very basic battery charger I mentioned, which is a Hobbico Multi Charger will work for you. It is just a box with 4 sets of outlets and selectable trickle charging. It does not do any type of balancing and will not work with LiPoly.

For your EDF jet, you are probably going to need something that is High-Power and can handle a couple sets of 5- or 6S Li-Poly packs. You will probably have some answers in the electric jet and electric helicopter pages…

Good Luck.