dell e1505 charger or battery issue

I have a Dell e1505 laptop that i bought about three years ago. 6 months ago my charger died on me, basically only charging every so often, so i bought a new charger off the internet. it worked fine up until last week when my computer ́s charging light, when plugged in, stays lit for a couple seconds, then turns off, then lit again, then turns off. After a day plugged in like this, i was able to boot it up for an additional 15 seconds but it either isnt holding much of a charge or my charger is not functioning correctly.

Is this a charger or a battery problem? it wouldnt surprise me if it was the charger, it was a $15 one off ebay. Think my battery is fried?