My phone’s battery had been on the fritz for over a year. It would last about 3 hours or so and then die at 45-50%. This seems to be something endemic to Huaiwei Nexus 6p phones. Other than this issue, I love the phone and don’t want to buy a new one. I tried to have it fixed in Taiwan, which you would have thought would be easy over there. Unfortunately, they do not care to work on mainland phones. I decided to wait until I got back in the US to fix it myself.
I bought a new battery and tools on Amazon for $14. My sister-in-law, Heather, has some experience working on phones, so I let her give it a try after a review of the procedure on Youtube. Unfortunately, while opening the case, the screen and thingie behind it cracked. No one’s fault, but I bought a new Huawei Nexus 6p off Ebay for $138. I was going to just use the new one, until I remembered that I had an interview with Aunt Jean on it. So, I cracked open both of them and performed major surgery. I got it down to the base innards and combined the features I needed into one phone. Youtube was great for this. That site can teach you how to do almost anything.
Update 6/17: New battery and screen is working like a champ. Love it.