Nikon Battery

I'm getting ready for a trip and thought I'd prep my camera batteries.

It's been a few months since I last used it and now something weird has happened.

I've left my camera charging from the USB cable to the AC plug for four hours and it won't turn on. I've tried charging it from my laptop, other power plugs and even my portable battery drive.The light is still blinking when I plug it in, but could it be that the camera is broken? Will I need to get an external battery charger? (the one...

Nikon Battery Nikon Battery