LiFePO4 flat cells for a battery pack.

[dfwdad]

I was looking at the Tenergy 3.2V 10Ah LiFePO4 cell and was wondering if this would make a nice battery pack for a plane with a 46 inch wing span? While it is a ten Ah battery you would have to run four in series to get a voltage of 12.8 with a weight of around 1112 grams, 39.2 ounces.

• 3.2V 10Ah LiFePO4 Rechargeable Battery.
• Maximum discharge rate: 2C.
• Maximum charge current: 10A.
• Maximum burst of: 30A.
• Recommended charging rate: 0.3C.
• Dimensions(L x W x T): 231mm x 82mm x 8.2mm
• Weight: 278 grams

[rcers]

No they are 2c packs and would not deliver the power needed for an electric motor. They are intended for use with Radios, both transmitters and receivers.

You want LiPoly batteries for flight packs.

Mike

[dfwdad]

Ok, I am new to this, I am guessing you need a current of 20 or up?

[rcers]

The battery current needed is determined by the motor and propeller. The LiFe packs are wonderful, but not for powering motors (unless you are talking about the "round" LiFe cells - they are very capable, but a bit heavy).

So help us help you. What is your plane, motor, esc? Then we can help you with the right battery.

Mike

[dfwdad]

Well I would like to run A123, and it has a great power to weight ratio for lifepo.

[rcers]

A123's are great, but many LiPo's are better (higher discharge ability) and lighter. Hard to beat that. And now the newest cells can be quick charged at 4 or 5c just like the A123's.

Flat LiFe cells are NOT up to A123's, don't put them in the same class. The ones you list for example are 2c. A123's are 30c+. Big difference!

Mike

[dfwdad]

Well you seem to know quit a bit about the battery tech out there, I am not looking at high power, I am looking for high energy density low weight. Do you have any ideals?

[dfwdad]

Ok, I found a site www.rclipos.com where it had a list of a lot of the batteries, I called the guy and he was very helpful and explained a good bit about the batteries. He recommended the Thunder Power 20C/40C G4 Prolite Li-Poly Batteries for the best energy to weight ratio.

[rcers]

Originally Posted by dfwdad

Well you seem to know quit a bit about the battery tech out there, I am not looking at high power, I am looking for high energy density low weight. Do you have any ideals?

LiPoly is the highest energy density for the weight. That is the technology you seek. That is why you see them used so widely in the hobby.

Hyperion is likely the class leader right now. Here is some great info on them.

http://media.hyperion.hk/dn/g3lipo/

Note the 45c discharge (above that of A123's) and the 6c charge rates. Impressive indeed.

Thunder Power are generally cutting edge as well, as you point out.

If you point out your application - we can certainly give you specific advice. So again - what are you powering?

Mike

[dfwdad]

It is a slow flying Wing Dragon with the 46 inch wing span, the last time I have flown was 20 years ago and it was a gas two channel plane. The Wing Dragon is a 4 channel trainer that I hope will live past my learning stage. My two boys want to get into FPV, but the only thing they have flow at this time are helicopters. So with me not flying a RC for 20 years and them with no model airplane experience, I feel this is going to be a wild ride. Right now the plane is factory with zero fight time and some ground taxi time. It is just to cold to fly, I hate the cold.

[rcers]

You you are using a sledge hammer where a tack hammer will work!

Just about any LiPo battery will work well there and provide you with great power and be nice and light.

You will likely be just fine...it should come back pretty quickly. While the Wing Dragon would not be my first choice of a get back in trainer I think they are pretty durable.

Since your local - if you want some help I am glad to do that!

Mike - by the way we fly in Trophy club at one of the middle schools or at the club field in Grapevine.

[dfwdad]

Yes when I get past just my taxi stage, I plan to take flight at Bedford's Pennington field.