Originally Posted by Duster_360

Storing them any time at all fully charged is supposed to raise the IR and will degrade performance over time. I charge mine to storage voltage after getting home and leave them that way until I get ready to use them and then charge them. The other thing I've seen talked about is not charging to full 4.2v/cell, but 4.1v/cell - that doesn't seem to cause the prob attributed to time at full voltage.