devfrag

Hello all. I have been out of RC for close to 10 years now and I got the itch recently to hop back in. w00t!!

I'm gonna do heli's this time and aside from the usual "Which electric heli should I start with?" My question is about batteries.

*rewind to around 10 years ago*

I was into battery powered cars. My BIGGEST gripe at the time was battery life. Granted, I had a more limiting budget at the time, but I spent a lot my time waiting for the charger to charge/discharge those batteries.

Then I said to myself, gas is the answer, right? Surely I can run "forever" with a gas powered car. Wrong! It was messy, klugy, smelly, and even more difficult to work on than electric powered equipment. Not to mention more costly. At least it was around 10 years ago anyway.

*fast forward to the present*

First off, I know that these will probably be loaded questions. I am just looking for some general information/direction at this point.

1. In general what types of batteries give the longest run time relative to cost?

2. What type of battery/charger setup would I need to have my <insert heli name here> in the air for a long time, aside from changing the batteries? (i.e. 3 batteries/2 chargers, 4 batteries/3 chargers, etc...) Oh and I have read about a tether that would allow for "unlimited" flight. Not totally sure about that but I want the heli to fly on it's own.

TIA for any and all suggestions

Dodgey99

do a search in polymer. The way forward is lithium polymer batteries (li-po). A heli like an eco 8 (nearly 1m rotor span) will fly for about 9 mins on an 8cell nicad or nimh pack and about 20 mins on li-po! A lipo pack costs more initially, but less than, say , 3 nicad packs.

Basically, li-po is the way. Even with modern nicad and nimh batts and a good charger, you can have 3 packs and be charging one (takes under an hour) whilst using another.

It's not a problem waiting for charges with helis as you really do need a break after 10 minutes, the concentration is that intense.

devfrag

!!!WOW!!! Those flight times are amazing and the batteries weigh ABSOLUTELY NOTHING!

Without a doubt I will be going with the li-po batteries.

How long are the charge times for these batteries?

Back to the second question posted above, what type of charger/battery setup will I need to keep the heli in the air for an extended period of time? (3 batteries/1 charger, 3 batteries/2 chargers).

Yes, I am being obsessive about the battery setup but if I want to fly for a long time, I want to fly for LONG time!

Here are a couple of links to what I have found regarding li-po packs.

Decent prices?
http://www.hobby-lobby.com/kokam.htm
http://www.hobby-lobby.com/chargers_lipoly.htm

Thanks again for any and all advice!!

Gazoo

I got two Etec 1200's from light flight.

http://www.lightflightrc.com/

I ordered a cheap charger from light flight and am using it until my SC2 charger arrives from B.P.P.

http://www.b-p-p.com/SC2.htm

Simbo

I got my batteries from


http://www.battlepack.com/LiPoly.asp

and the 12vdc only chager ET-SMARTCHG-2 from the same place

http://www.battlepack.com/chargers.asp

charleyh

My Feedback: (1)

Battery type depends on what heli your going to get.

Post more info and we can help more.

I have a Corona and have both LiPo and NiMh batteries. I can get about 10 minutes on a 8 cell NiMh pack and at least 3 10 minute flights out of a Thunder power 2s4p 7800 LiPo pack.

The NiMh pack will recharge in about a half an hour though.

If you run the LiPo battery down most of the way it takes over 2 hours to recharge.

I use a Schulze 6-330 charger and it charges pretty much every type of battery there is.

Let us know what you're looking at getting though.

See ya,

devfrag

Hmmm...2 hours?!?! That is more than I would have thought. I know that NiMH is a newer battery(newer compared to 10 years ago anyway). The 10 minute run time/30 minute charge time is familiar to me(NiCad was similar I think).

If it takes 2 hours for the li-po batteries to charge, then I will be spending lots of money on packs and chargers to have this flight time setup that I want. Yuk!

More thoughts anyone?

I've really bounced around on this one, but I've narrowed it down to the following choices. I like the look of these 2 birds and they have received several favorable reviews.

• ECO 8
• Corona 120

TIA

charleyh

My Feedback: (1)

Basically NiMh and Nicad are very close. NiMh has a couple of advantages. Less memory effect, More power in similar cells. They charge about the same though.

Here is a thought, You could get one Lipo battery and one NiMh battery. Fly the Lipo while the NiMh is charging then fly it. Then switch back to the Lipo and charge the NiMh battery again.
You could probably keep your bird in the air for quite some time this way, and probably get5-6 flights in which is a pretty good day at the field for me.

I don't know much about the ECO 8 but I have a Corona and a Logo 10.
If you have no experience I would recommend the Corona first then the Logo 10. The ECO 8 is a bit more fragile than either one of these from what I understand.

Hope this helps, and feel free to keep the questions coming.

Charley

devfrag

So with that recommendation Charley, your saying the the Li-Po batteries do not suffer from memory problems?

If that is true than this may be the solution I am looking for!! w00t!!!

charleyh

My Feedback: (1)

With Lipos there is NO memory effect. You can fly it and run the battery down halfway and then charge it and it will not hurt it t all.

In fact it is recommended not to discharge completely.

With my NiMh batteries I run them on a discharge/chrge cycle on my charger, this drains the little bit that's left in them before recharging. With Lipo's you don't have to do this.

They are great batteries.

Gazoo

That is all good advice. I am considering an EoLo for my next heli, but I have not ruled out a Logo. Currently just have a HB.

I would only add that LiPo battery chemistry is relatively new, and is evolving. Charging times will come down with newer chemistry, and so will prices. I believe that the next generation batteries will charge in half the time it takes for the current ones, and I expect to see that battery density will go up some as well. Irregardless, the high current LiPos that are currently out there are awesome.

Consider that a stock NiMh birdseed pack for a HB is around $12.00 and flight times are 8 min. max. With a 1200 Etec battery that costs $30.00 - $35.00, the flight time increases to at least 20 minutes, and the battery is much less than half the weight of a birdseed pack. So the LiPo ends up not being a bad investment after all