iphone 5s genuine battery
where can i get iPhone 5s genuine battery.
i purchased but it was not genuine.
iPhone 5s, iOS 8.3
You cannot. There is no supplier of genuine OEM parts for any Apple iDevice. If you take it to Apple, they would have replaced the battery for a fee. Now that you've tried to do it yourself, you are not even eligible for out of warranty service.
Idevices are only serviceable by Apple or an Apple authorized repair center, so they are the only ones who can get their hands on OEM parts and they do not sell those parts separately.