This has been discussed in RCGroups EDF forum. The general consensus is that properly cared for, "stored" state, Lipos are safe. They can be stored for several years this way.

There is a bit of justification, because this is the way they are shipped from the manufacturer and obviously they have a warehouse full of Lipos in this state.

Caveat: exception would be an FEJ Lipo if they make em. : o