If you get one on Amazon make sure it specifically says "new" and "zero charge cycles". There are a lot of cheap ones that were pulled from used devices for sale on there.
I once bought an iPhone 5S battery replacement from eTradesupply, no complaints, here is the source:http://www.etradesupply.com/oem-apple-iphone-5-battery.html hope it helps, good luck.What online sources is the best for purchasing an iPhone 5 battery? I've seen a lot on Amazon but not sure what is a good battery or not. What should I look for when selecting a battery for replacement?