Hi guys I have a very strange problem with an iPhone 5s. Here's the story: I received this iPhone from someone who thought is was totally broken. A couple of weeks ago, it started to act weird, they replaced the battery, but it didn't help much and in the end, the iPhone wouldn't power on any longer. So they gave it to me, and I tried again to put a new battery in and ... The phone just powered on and was working fine, but suddenly it showed a blue screen (the blue screen of death?) for 2 seconds and restarted itself. When the restart was complete, I could again work with the iPhone for fifteen minutes, and then the same happened (blue screen, restart). When I tried to recharge the battery, nothing happened (the phone said it was charging, but it wasn't) and eventually the battery died. I have another 5s laying around, and after some experimenting, I found out that the problem is very simple. Every battery I put in this 5s works until its power is gone, and then you can't recharge it. When you put this battery in another iPhone, it turns out the battery is completely broken (It also won't charge in tis other iPhone). So ... Every single battery brakes again and again in this phone. The charging port cannot be the problem since I have replaced this as well, but it didn't help. Do you guys know what the problem could be? Is it fixable? Thanks a lot!