I think it was left uncharged long enough that the lithium battery dropped too low in voltage, and it will no longer allow recharging. Problem is that the battery seems to be dead. It's an 'Omni2 2009-EF6-HDLM', and appears new and unused.
Not a really nice one, but it is in my possession, and I would use it if it worked. I've been cleaning up, and digging through stuff that we brought back from the Minnesota house that we are working on.