nhhover

My Feedback: (1)

I have battery voltage testers for nihm and lipo batteries..... I am using a LiFe battery in my next biuld but I can't seem to find a tester. Does anyone know of a way to test it at the field?

Thanks, Ron

K-Bob

My Feedback: (1)

The only safe way to use LIFE and A123s is to make a flight, recharge and see how many Ma the charger puts back in. Then do a couple of flights and recharge etc. You should be able to get a pretty good idea of what you use in a normal length flght. I prefer to use around 50% of the pack capacity as a stop and recharge point. If you use something like the Cell Pro Multi4, a 2300Ma pack that has a 50% discharge takes maybe 10-15 minutes to recharge.

Stick 40

I just started using A123, and read that testers ( or test meters with load ) don't work on them.

For my money a good charger that works on Lipos and A123's with a read out is the best way to go. The chargers mostly have a LiFe setting and that can be used for A123's also . A good one will charge and discharge and give mili amp read outs.

I charge the A123 and lipo's and read the charge amounts and discharge mili amps. Most people try and stay above 50% of actual capacity when flying.

not sure if I am explaining the charge and discharge clearly, some one will chim in and help out.

JeffinTD

I'm new to them, too.

As I understand it, voltage testing won't give you an accurate idea of state of charge because they tend to have a very flat discharge curve- they maintain virtually the same voltage until they are completely discharged.

I guess the thing to do is select packs which should provide the mah's to run your plane for the amount of flying you want to do between recharges- then do like the post above: fly a flight or two and see how many mah it takes to recharge.

BarracudaHockey

My Feedback: (11)

K-Bob nailed it.

I've been doing it that way for a while, it works like a champ.

landeck

My Feedback: (1)

Here is what you want from Futaba:

http://www3.towerhobbies.com/cgi-bin...1&I=LXBHZW&P=K

I have one on order for the same purpose as you - to check the status of LiFe batteries.

Bruce

Jeremymac

Good !!!! major questions I had too, thanks for the link to the tester. I have one more question. On a life battery they have receiver leads. Would it be ok to run 1 lead to the receiver, and 1 lead to a regulator to the ignition?. Have switches on both? Any info would be great!!!! Thanks Jeremy

JeffinTD

I don't think you want to run the ignition off the same battery, at least without a filter of some sort to isolate the receiver from the "noise" created by the ignition.

Here is a filtered and regulated ignition battery eliminator, with an optically isolated kill switch.

http://www.syssaaircraft.net/cart/pc...5&idcategory=2

K-Bob

My Feedback: (1)

No way. You are setting up for a disaster. Did you even read the tech notes, especially the last line?

NHHOVERo yourself a real favor and do some research. </p>

landeck

My Feedback: (1)

Yes, I did read the last line which states "Since the voltage changes with the individual battery and the ambient temperature, use the remaining capacity display as a criteria only."

Which means that it should not be used as an absolute reading or the only criteria as for estimating remaining capacity. The way it should be used is when starting with a full LiFe battery at the beginning of the day, use it with caution in estimating how much capacity has been used as the day progresses. You can verify the reading by seeing how much capacity is being used per flight and was actually remaining at the time you re-charge the battery back at the shop. ESVs give one decimal place accuracy in reading a battery's voltage and is fine for estimating the remaining capacity of NiCad/NiMn batteries but is not useful for Li chemestry batteries because of their much flatter discharge curve. But these new instruments are giving 2 decimal place or better accuracy and therefore can be used like the old ESVs for the same purpose. Used properly, these new instruments are no more "setting up for a disaster" than the old ESVs, in fact it may prevent a disaster.

Bruce

bilal792

I've also had trouble finding a reliable LiFE battery tester for my RC setups. From my experience, using a good charger that displays individual cell voltages and balances them properly has been very effective. It’s not as convenient as a dedicated tester, but it gets the job done well. For those who mentioned the importance of discharge curves, I completely agree – it’s crucial for maintaining battery health. Thanks to everyone for sharing your insights!

soupninja

Are you using Life batteries for your flight pack instead of Lipos? How does performance vs weight compare? Life is a safer battery and no self discharge which I like