I do realize that there has been several forums on the topic, but mine seems to be unique. I have 4 NEW batteries 1 on the Mavic Pro and then 3  purchased seprately as back up. The unit was purchased 2 years ago and has sat since purchase never opened or charged. It was purchased for football videoing football practice and games. I fianlly opened up the unit and tried to charge the batteries last week and nothing has worked. I used the hub to charge all four at a time and then tried charging individually with no luck. Any suggestions. I have a lot of money into this unit for having got zero use out of the batteries. I have a feeling I need new batteries. Thank you for any thoughts or suggestions.  

If the batteries haven't been maintained for more than 2 years you will probably need new batteries,  you could try leaving one battery on charge for 24 hours and see what happens.

Thank you DAFlys. I appreciate the help. Unfortunate rookie mistake by me.