Default Will sprint replace the battery?

I am considering picking up a used evo lte for my daughter as her first phone. My only concern is that the phone is now "old" and the battery could be worn out. So can I pay Sprint to replace the battery?

I can replace it myself but I can't find what I would think is a legitimate battery. The only one on Amazon gets bad reviews.
Hello, My name is Andrew and I am a Flashaholic