lipo questions
07-26-2007, 10:07 PM
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lipo questions
Is it correct that Lipos have no memory? I can run my lipo and put it on the charger at any time? Is it better to charge lipos under 1C or will there be no difference at 1C? I have a 2S lipo battery and run a cut off voltage of 3.4 v (per cell). I run a balancer when charging, is there anything else i can do to prolong this battery's life?
Thanks!
Thanks!
07-27-2007, 08:21 AM
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RE: lipo questions
ORIGINAL: SeanF
Is it correct that Lipos have no memory?
Can not remember just recharge
I can run my lipo and put it on the charger at any time?
YES
Is it better to charge lipos under 1C or will there be no difference at 1C?
YES C/1 is max so if charge less than get more cycles maybe 20% no hard facts
I have a 2S lipo battery and run a cut off voltage of 3.4 v (per cell). I run a balancer when charging, is there anything else i can do to prolong this battery's life?
YES cycle no more than 80% capacity also store lomg term "aka Month" at 40 to 60 % charge and cold. less than 70 deg for long life and lower int resistance.
Thanks!
hope this helps
Rich
Is it correct that Lipos have no memory?
Can not remember just recharge
I can run my lipo and put it on the charger at any time?
YES
Is it better to charge lipos under 1C or will there be no difference at 1C?
YES C/1 is max so if charge less than get more cycles maybe 20% no hard facts
I have a 2S lipo battery and run a cut off voltage of 3.4 v (per cell). I run a balancer when charging, is there anything else i can do to prolong this battery's life?
YES cycle no more than 80% capacity also store lomg term "aka Month" at 40 to 60 % charge and cold. less than 70 deg for long life and lower int resistance.
Thanks!
hope this helps
Rich
07-27-2007, 06:46 PM
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RE: lipo questions
So it is best to always cycle lipo batteries? Should I take them down to 3.2 v/cell?
I just want to make sure my lipos last as long as possible.
I just want to make sure my lipos last as long as possible.
07-29-2007, 09:16 AM
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RE: lipo questions
Hi Sean,
You are on the right track, richrd gave some good advice. I believe when rchrd referred to not clycling more than 80% of capacity, he was referring to cycle in the context of normal use, lipo batteries have no memory and should not be cycled as we did with Nicds in the past, to do so just wastes battery life.
While a cutoff of 3.2V per cell is very conservative you should avoid discharging them down to that low as a no load voltage, when your ESC cuts off at that voltage it is under load, if you measure the no loasd voltage after the flight it will be higher.
Good luck,
Pete
You are on the right track, richrd gave some good advice. I believe when rchrd referred to not clycling more than 80% of capacity, he was referring to cycle in the context of normal use, lipo batteries have no memory and should not be cycled as we did with Nicds in the past, to do so just wastes battery life.
While a cutoff of 3.2V per cell is very conservative you should avoid discharging them down to that low as a no load voltage, when your ESC cuts off at that voltage it is under load, if you measure the no loasd voltage after the flight it will be higher.
Good luck,
Pete
07-30-2007, 03:04 AM
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RE: lipo questions
if you want to leave 20% in the packs, I find the best way for me to do it is take a no load voltage, and if it comes in right around nominal, or 3.6 to 3.8ish then you are looking pretty good, any lower than that though and you're running your packs too low, atleast what I have found with my packs.
07-30-2007, 08:29 AM
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RE: lipo questions
All good advice I take it you do not have a charger that tells you have much capacity it is putting back in. This was my inferance to only putting back 80% with 20% unused. Do not confuse load cutoff to voltage at rest. After 20 minutes battery sould never be lower that 3.5V/cell after run. The stop voltage under power is dependent on your settup. So the tought here is if you have no way to measure how much charge you are putting back yea run .. stop wait 20 minutes measure use 3.6 -3.8v as lowest to be safe.
The only time you cycle a LiPO is when new or have not used in a long time AKA > 6 months. 3 cycles at 1C is the numbers I hear and use no harm no foul.
Rich
The only time you cycle a LiPO is when new or have not used in a long time AKA > 6 months. 3 cycles at 1C is the numbers I hear and use no harm no foul.
Rich
