Originally Posted by
Rocketman_
The best receiver battery for me is Li-Ion. A123 is a great advancement in battery technology but not for me. Once I found out that there was no field instrument that could accurately keep track of A123 battery voltage, I abandoned the idea of using them in my models.
My RC experience goes way back to "ancient" times and I have never had to charge a battery at the field and don't want to start now. I just don't feel like doing the A123 routine of charging, flying, recording flights, charging to see how much you put back in (as if that is accurate), etc., etc., and continuing to do that over the lifetime of the battery to see if it changes.
Li-Ion and regulators have been totally reliable over the years in my 1.60 glow to 36cc gas powered 3D and sport aerobatic models. I switched from 2600 mAh to Panasonic 3400 mAh Li-Ion when I started connecting the ignition unit to the receiver. These 18650 size cells can be purchased two for $17.99 from Amazon and easily soldered to make a 7.4V 2-cell flight pack.
http://www.amazon.com/NCR18650B-3400.../dp/B00DHXY72O
Troybuiltmodels sells a 3400mAh 7.4V 2-cell Li Ion pack all made up with 3 leads and connectors for $34.95.
http://www.troybuiltmodels.com/items...LIION3400.html
I've got over 100 A123's in my various models. And outside of completely screwing up two cells over the years, never had a failure. Some of those packs are 7 years old, and they've been pulling 40 Amps per cell. Flying LiFe or A123's is like driving a car with a busted gas gauge. Drive a safe distance and top off the gas tank. Or with A123's just never use over 50% of the receiver battery during any flying session. IMHO that is good policy, no matter what the battery chemistry, Li-Ion, A123, LiPo, Nih, or even lead acid.
The important part of all of this is, the receiver battery or power supply (BEC) must absolutely be bullet proof. And voltage sags below the receiver minimum operating voltage simply can't be tolerated. Li-Ion, A123, LiFe type chemistries are a good step in eliminating this type of receiver low voltage = crash. What I use in my giant scale models is a Castle Creations 10 Amp Switch Mode BEC, with a two cell A123 battery with diode isolation as a backup.
Out of curiosity, what is the voltage on that 3400 Mah 7.4 V Li-Ion pack immediately off the charger?