My iPhone 4s only charges until 4%, and then dies! Why?

I have an iPhone 4s in good condition, and I recently plugged it into a charger, which was in bad condition, and the charger wasn't working, so I went out a bought another charger which did not work either. So soon after I used someone else s iPhone charger, and came to find out my phone only charged until it turned on at 4% then dies after that! How do I fix this, please help!

It might be something wrong with the battery.go into an apple store or call your service provider

Time to replace the battery.