Hi All,

What do you guys prefer when powering your RX....I'm considering going with dual 6.6V LiFe batteries straight to the RX, but I know many of you guys seem to prefer to use 7.2v lipo's with regulators. Is there an advantage to going this route over the 6.6v LiFe straight in? Or is it just a personal preference?

Thanks in advance for your input!!!

For me Life. One less component that can fail(regulator)

Here is my two cents. Dual A123s ( I wont use any other Lefes) to dual switches directly into the receiver. I have been flying this setup for a number of years now and have been very satisfied. Scotty

Dual life also

Dual LiFe batteries with JR. power safe recievers. On all Turbine powered models except my Hawk. It has dual LiPo with regulators and power safe rcvrs. I prefer the LiFe setup

Dual A123's + EQ10 (SmartFly) and you are good to go....

+1 I can't think of a better system. Bolus amps right to the receiver and a tiny softswitch to turn on and off. Perfect.

A123. There is nothing that comes close. The soft swithch with Power safe if you use JR, or the Smartfly or other power system.

HI Jetfan
For what it is worth I use only A123's but with a Regulator I have had 2 Servo's fried by using them straight into the receiver.I was lucky one was on my brakes and the other was on the retracts and before any one can say that they were probably stalling I can assure you that they weren't. I had a thread on this very problem late last year. I run 5.8 volts now and have not had a problem in any of my jets since. The only common between them was that they were both on short leads not sure if this was the reason but I wasn't going to take any more chances.
Cheers
Mav

Dual A123's + EQ10 (Genuine A123 Systems), I made my own pacs from single cells. (Buying from HobbyKing: http://www.hobbyking.com/hobbyking/s...ll_w_tabs.html )
Check that your servos can handle the voltage, most of the receivers can.

over the past winter I switched all my batteries over to the Life 6.4 battery packs in my jets. should have switched to them last year...


Mark

I have both set-ups and prefer dual LiFe, why worry about a regulator.

Just to be clear, LiFe are NOT the same as A123s. A123s are LiNP. A123s are a better choice for high dollar airplanes. LiFe batteries come from a number of different sources and may not have consistant quality.

The choice should be between A123s and LiPo. I wouldn't consider LiFe, unless the source is reputable. Even so, there is no disadvantage I can think of with A123s.

Dual A123's and an Orbit power jack for me

Chris brings up an good point. There does seem to be some confusion , at least in my case, about the difference between the "LiFe'' batteries and the "A123" sytems batteries. My understanding is the A123 company developed the lithum ion technology and then marketed them as "A123" a trade name. This may or may not be true. So confused as I am , it's off to Google .

From" A123 Systems" website is this quote " A123’s products are built using our breakthrough Nanophosphate® chemistry, a proprietary form of lithium iron phosphate (LiFePO4)"

This information helps me a little but still does not completely clear up the confusion. The batteries I use are the flat pack LiFe that Hobbico markets, available from my LHS. I believe the "Real" A123 are only available in cylinders.
So CHris you are probably right. We can continue the discussion when we next meet. Looking forward to KY jets. Hope to see you there


Glenn

what is your source of confirmation about the quailty of the Life batteries. I run daul Life batteries and they work just fine, which are run through my "Electro Dyn amics" Battery Backer system.

Mark

No matter what battery you use (and ALL of the above work great). It is important that you learn everything about the battery of your choosing.
Pay attention to the numbers that the charger gives you both at the beginning of a charge and the end of the charge.
Keep track of how many flights you flew vs how many mah it took to recharge.
Check your batteries between flights.
You do this and battery choice will be the least of your worries.

I've paraphrased some of the comments found on the NoBS and A123 websites. In addition, we have data coming from bench level and flight testing I'm doing for a DoD aircraft project. The chosen technology was A123 packs made of LiNP P04 cells. The packs are used as the sole source of full scale turbine engine starting power and weapons firing. The Government and aviation requirement puts emphasis on sustained power, long life, and a cell that doesn't flame (LiPos couldn't even be considered).

These are the same cells that are used in packs produced by Electrodynamics, NoBS, and a few other sources that use authentic A123 battery cells for RC modellers. Unless they say they are A123s, they are not the same. Sometimes the price can be a clue. A123 cell technology is proprietary and only available to battery makers from A123 Systems.

True A123s are one of the few real bargains we have in RC jet modelling considering the role they play.

The NoBS guys will tell you that A123's plating technology provides an increase in cell life. Since batteries consume negative plate over time, A123 systems increased the negative plate surface area by up to 100 times compared to any competitors plating process. The lifespan of the A123 cell is better.

NoBS: "In comparison to other LiFE batteries A123's use a patented 'Nano' plating technology that improves the negative plate material. This allows a much larger amount of surface area for A123's negative plate and it's why A123 can tolerate larger current loading without voltage sag [brown out]."

"Brown out" is the issue jet pilots should be most concerned with, assuming the batteries are being maintained properly. Due to the high demands of digital servos, servo count, longer extension leads, and airloads, the battery system becomes the radio's choke point. The ability for the battery to handle the peaks as well as sustained loads and continue to provide stable voltage is the goal. We have to up the "C-rate" to keep the radio happy. That is why many guys use good quality LiPos too. Quality LiPo packs have good capacity and higher C-rates when needed to sustain voltage.

The NoBS guys will tell you that A123's plating technology provides an increase in cell life. Since batteries consume negative plate over time, A123 systems increased the negative plate surface area by up to 100 times compared to any competitors' plating process. The lifespan of the A123 cell is better.

Further: "A123's also use aluminum cased cylindrical cells with welded alloy end plates and towers like a Nicad cell. This enables a welded strap pack assembly system (like Nicads) that is stronger and resistant to vibration and impact. Other LiFE packs are built with wafer stacked 'bag' prismatic cells.. like LiPoly. And, like LiPoly, they are fragile, the cell link tabs are very thin alloy strips and the entire assembly is as a result susceptible to rough handling and vibration. Further, the prismatic cells and their tabbing system are unable to handle anywhere near the current loading the A123 system can tolerate with ease."

A123 systems quote:
"Nanophosphate is a positive electrode material of remarkable rate capability, critical to high power systems. Our high power products are able to pulse at discharge rates as high as 100C."

The Nanophosphate Advantage:
High Power:
Higher charge and discharge rates for better performance and efficiency
Higher Usable Energy:
Wide SOC (State of Charge) range enables greater battery utilization
Excellent Safety:
Superior abuse tolerance
Extended Cycle Life:
Long battery life for both deep and shallow cycling.

For the price differential, it may not make sense to use 3.3v Li-ion family cells that aren't true A123s (LiNP).
We can always get away with most any other battery types, but like other components you tend to get what you pay for. I often wonder how many battery "brown out" problems get blamed on radio RF or other airframe issues.

I will never use A123's. to me A123's are the same as DA engines lol they get the job done but so do LiFe and DLE engines at a reduced price. My Opinion

Now all i use are the Hobbico and Hyperion LiFe batterys. They out perform the Nicad and NiMh batterys. they are half the weight and have the same Mah rating.

What you need to pay attention to is the C rating of them. some of the Hobbico LiFe batteries only put out 1C some are over 10C.

Onother thing i dont like about the A123's are they only come in one size and they weigh more.

I have crashed a couple of LiFe's at over 140 into the ground and the battery was crushed and split open. it was mounted behind the engine, reciever, servos, fuel tank and wing mounting block. it ripped through all that. It didnt catch fire or even get warm.

I have HV serovs also on most planes now and still use the LiFe batterys. IMO for todays tech its the only way to go.

I have had 2 of the cheap hobbico LIFE batteries fail. They did not all out fail but the capacity on them was down to about 15% of what they should have been.

I have now switched to all real A123 batteries and could not be happier. No regulator.

I have a dx8 with telemetry on most of my planes and I have replaced all my nimh batteries after recording in flight voltage drops as low 4 volts with them. I use mainly dual turnigy life batteries with a min. of 30c discharge and have next to no in flight voltage drop now. I did also find a switch that was causing a voltage drop in a plane so I replaced the switch with 2 new switches with dual batteries! I'm sure countless radio manufactures have been trashed by rc pilots after crashes when the TRUE culprit of the crash was a weak or worn out reciever battery

So true!

I still prefer Li-Ion for Rx packs myself. I run Fromeco products, as I think Kurt puts together about the highest quality power system I've seen.