After recovery mode, the whole iPhone no longer works

Good day, ladies and gentlemen,

I have an iPhone 7 Plus which showed the recovery mode after a while. I tried to bypass it, but the iPhone is turned off by itself. Now I have used a tool to switch off the recovery mode at the push of a button, because it can not even switch in DFU mode. After the recovery mode is no longer displayed, the whole phone does not work. However, the battery needs a service, does the phone work after the battery repair? And how does it happen that the phone doesn't work at all from one moment to the next?

Dear greetings