An Pixel XL phone shutdown by itself

My Pixel XL phone rencently always turns off by itself. Most times it turned off just after starting up, a few times it worked longer and everything looks fine. when it happend, a "phone is shuting down"(maybe not exactly these words because my phone is not in english) dialog pop up and then shut down in a few seconds. I tried restoring it to factory image, and tried replace a new battery, and had not fix this. I got the log using "adb logcat", here is it : full log file Now I think its because of a hardware part, but seems not battery. I want to find out which hardware part is it from the log file, but I don't know much about the log messages, can anyone help to find some clues about what cause the auto-shutdown? Thank you very much! John.