Not sure if battery issue is fully related but...

As a former owner of a T470, Lenovo included a pretty beefy component from intel that was supposed to be feature complete by itself for dynamically managing thermals, including funky ideas like detecting if you were potentially using the laptop on your legs etc. and reducing thermals then, but giving full power when running plugged on the desk.

Time comes for delivery, Lenovo finds out that intel did a half-assed job (not the first time, compare Rapid Start "hibernation" driver earlier) and the result is kabylake T470 (and X270 which share most of the design) having broken thermals when running anything other than windows without special intel driver, thus leading to funny tools that run in a loop picking at an MSR in the CPU in a constant whack-a-mole with piece of code deep in firmware.

Its possible. I know from the BIOS revision changelogs that the T470 did get a patch to fix this, but the X270 never did.