How to fix my dying battery?

[AC Question]

My phone (LG G5) was perfect. It would take hours for light use for it to go down even a few percent in battery life. Two weeks ago my phone updated to nougat and everything seemed fine until 2 nights ago the battery started draining 10 % in 5 minutes of use and about 10% in an hour of no use at all. The battery also overheats a lot and stays warm when not in use. I did not download any new apps. I have done safe mode and the third party apps are not the problem. I have done a factory reset and it still won't work. I have also tried disabling all apps I am not using and turning of off thier background access. My battery tracker indicates terrible battery usage, but says nothing it causing it, other than phone idling and the screen. Battery saver is fully up and working. The gps has been turned to not being highly accurate. Nothing works. LG G5 is sending me a new battery but I think it's the software because the battery is not bloated. Lg says they cannot help me of its software and that it is googles problem!!!! That is ridiculous and Google does not provide have any help for people in my situation because I am one person. I bought my phone outright and refuse to accept that I have to accept this after paying that much money for it! I bought it so it would work great, not to have a faulty product. If anyone knows own how to solve this it would be greatly appreciated!

 

[belodion]

My own diagnosis for what it's worth is that the battery may need replacing.

 

[AndroidUser17]

No, it is not a battery replacement needed, I had changed 3 times my phone applying the warranty and for the 3 of them the same problem, battery drain and phone warming up after Android update, there is a problem with the new software release
I had reviewed everything and tried all that forums recommend, there are 2 applications draining the battery, LG Backup and QuickNote with almost 80% of battery in a 3 hr period, this is not a hardware issue, the phone was working good before the update, who can fix this Android issue ???????