LI-FE batteries
 

I am thinking about getting a few of these http://cgi.ebay.com/Intellect-Li-Fe-...d=p3286.c0.m14 for my reciever packs because my lipos need to be replaced, 2S Lipo is 7.4/8.4 fully charged, These are 6.6/?? what are they fully charged?? And do they stay consistant all the way through and then dump at the very end like a lipo or do they just degrade slowly and inconsistantly like NIMH??? Another reason I like them is if you over-discharge them you dont ruin them, I like lipo but man thats F-ing stupid IMHO.

Thanks for any info........ David S

LiFe batteries are lower voltage. they are 6.6 charged. i dont know their discharge characteristics.

6.6 volts is a nominal spec. Believe they are 7.2 volts fully charged. 3.6 per cell.

i use A123 (same batt chemistry) and I find that they dump huge amp amounts, but they drop in voltage under heavy load, now you won't get this from using them as an Rx battm so you should be good....

The voltage will stay the same and then once it done the battery loses power almost instantly...

However if they are the same type of batts as the A123, then you can charge them at 4.35amp all the way too 7.25amp...

This is probabley a stupid question but can these batteries be charged on lipo mode or do they requier a li-fe specific charger.

You need a charger with a LiFe specific charge mode. There's not only a voltage diff, but LiFe is not governed by 1C, 2C, etc charge rules like lipo. I charge my pacs at 10amps and thats only because thats the max my charger can do.

A way to deal with the low voltage is if you were running XS lipo (X is cell count), you run X+1 LiFe and it'll be pretty close. Where I use 5S lipo, I use 6S LiFe.

with regards to li-fe batt, there are numerous discussion if it works with 6V servo like Sanwa ERG-VX

some say they work fine, some recommend not to try. so what are your opinions?

Sanwa ERG-Sanwa ERG-VX:
Speed : 0.10 sec /60 deg. (6.0V)
Torque : 13kg.cm (6.0V)
Size : 39.0 x 20.0 x 37.4mm
Weight : 62g with cooling alum case

i have been using the 1700mah of the same battery, only issue was when i originally got it i charged it on lipo mode with a new charger (rtfm!!) and it peaked at 8.4 like a lipo. i tried to run it but it would die after 2 tanks. in the process of returning it i thought to drain it some and try life mode with a lower voltage. in life mode the charger would read over voltage and cut off. i drained it about 1/2 way then re-charged it in life mode and it has been fine since. the 1700 will easily do an hour main and they charge quick too, unlike lipo they charge at 1.7amp longer and only trickle the last 100mah or so. as far as the voltage goes for servos, a fully charged 5c nimh pack can reach 7.8v, the life peaks at 7.2v. so any servo that can run on a 6v nimh is definitely safe to run on a 6.6v life. in my opinion with the safety and durability of a life pack there is no better option fro an rx pack. and they can be balanced so unlike a nimh you won't have 1 bad cell ruin the pack.