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Electric Stunt => Gettin all AMP'ed up! => Topic started by: linheart smith on February 13, 2007, 06:01:09 AM
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How should I/we be caring for our expensive batteries during the off season?
Linheart
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Hi Linheart,
If you plan to store your Li-Po's for a long period of time (all winter) store them at ~3.8 volts per cell and put them in the refrigerator (35-55 deg). The cool temperature slows the chemical reaction extending their lifespan. If you do store them in the refrigerator let them warm up to room temperature before charging/discharging.
If you are flying them every week or every other week you can store them at any voltage (above 3 volts per cell) and you can store them at any temperature (above freezing). You won't see any degradation if they are not stored in ideal conditions on a week to week basis, only long term.
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Mike,
as a total newcomer to elect, I have a set of batteries, how do I measure that voltage, at the connector, or can i hook it to the charger? I want to insure that these batteries last as it will be a month or more before I probably have an oppurtunity to install and fly them.
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Mike,
Thank you. I was close. I charged and balanced all of my batteries and stored them in the basement workshop. It is about 60 degrees down there.
Linheart
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Mark,
One way to measure the voltage is with a Multimeter. Let me say to be very careful, because you don't want to short out the terminals with the multimeter probes--that should give a nice arc! I have used some straight pins to test each individual cell at the balancing connector.
On my Astro 109 charger, I could use the discharge function and simply stop the discharge at the desired voltage--since it is being read out.
Because I am an eternal optimist right now (despite 40 mph blowing snow outside the lab), my batteries are charged up fully---waiting for that elusive day I can actually try one of these things out!
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Mark,
What Alan said is good advice. A multimeter or charger will work to measure voltage (if your charger has a LCD display and shows voltage). Deans connectors are the easiest to "short" against each other while soldering or measuring voltage. Use heat shrink tubing or electrical tape to help cover exposed terminals.
Linheart,
It would be interesting to see just how much is gained over the years by storing a Lipo at ~35 degrees vs 70+ degrees. The Lipos I use in the Silencer are from April 2004 + or - a few months. For the first two seasons I stored them in what ever state they came home from the field in (charged or discharged). I also stored them in the basement which varies from 55-75 degrees throughout the year. Their performance is dropping off, but I expect to get at least one more season out of them. When they are no longer up to the task of powering the Silencer they can be used for sport flying, scale flying or training...... Hmmmmm time for another new project.
My next set of batteries will be taken care of from the start and I will see if I notice any difference. I will also record the number of cycles.
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Thanks for the input Gents