How to follow problem?

sabrallah, correct me if I'm wrong, but it appears you've run a kernel panic analyzer on a phone that is presumably bootlooping every three minutes or so. The analyzer is telling you that the CPU has lost communications with the battery and is listing all the likely causes of that happening. If we could see the same information that analyzer is using then we could give you a better idea of what approach to take to fix the issue.

@flannelist has written an excellent Wiki article on kernel panics and panic logs that describes the source of the data your panic analyzer is using. If you could follow the instructions to access your phone's panic logs and either screenshot or copy/paste the first page or so of the panic log, that will give us more to go on in helping you figure out what's going on with your phone.

iPhone Kernel Panics - iFixit

That being said, your analyzer is suggesting the following fixes:

1. Replace the battery. There are electronics within the battery that communicate with the processor, and the ones in the battery may have failed.
2. Replace the charging port flex cable. I wouldn't suggest this as one of the first things to try, since that flex cable isn't directly involved in the communication between the battery and the motherboard, but rather would be related indirectly in that it carries the power from the lightning port to the power controller and then from there out to the battery.
3. Check the battery connector for any signs of bent or broken pins. This is also low on my priority list unless you've opened up the phone recently for some reason; those connectors don't just spontaneously go bad inside the phone.
4. Check the flex cables involved in the charging circuit; presumably they're referring to the one going to the battery and the one going to the lightning port. Again, unless you've had the phone open for some other reason or some sort of damage has occurred such as being dropped, these wouldn't be among my first priorities.
5. Everything else involves board level debugging with specialized tools that would not normally be something you'd think of as a DIY repair.

Once we can see the panic log you're getting, then we should be able to point you in the right direction. Until then, my personal opinion is that you're probably looking at a fairly straight-forward battery replacement as the fix for your problem, but at this point that's just a guess. Here's an article on editing and adding pictures to your question.

Adding images to an existing question - iFixit Repair Guide

Good luck; let us know what you find!