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.

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

 

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.