Not sure about the eDGe, but on my ASUS laptop the battery will occasionally stop charging at 98% as a way to prolong the capacity over the battery's life. The idea is that if you're frequently only charging a partially used battery, then you'd rather get more, slightly less full charges than fewer, completely full charges (and increasingly less capacity after a year or two).
Try running down the battery to empty and then charge it. On my ASUS, that will make sure that it will charge completely to 100%. My guess is that the eDGe is employing similar technology.