Originally Posted by
Steve Meliza
One lithium battery is not the same as other lithium batteries, it depends on what you pair the lithium with. For example, DeWalt has some "nano" packs (eg. DC9360) with LiFe (aka A123) cells that the RC model airplane community tears apart to use for electric powered flight as they can output enormous amounts of current (~60A) and are nearly impossible to kill from over charging or discharging and can be left fully charged with little or no degradation. What kills most lithium packs is being left fully charged as the high voltage causes breakdown in the cells, reportedly as much as a 10% loss in capacity per month. The ideal voltage to store a lithium pack at when not being used is half charged, but anything about 10% below fully charged will help extend their life.