m15R3 shuts down

Hi all, 

Recently my laptop suddenly started to shut down on battery power even though there was still +- 61% battery power remaining.
After a few checks and online hardware diagnostics and bios hardware diagnostics I got warnings about battery performance.

Installed a new battery but unfortunately the same behavior.
The laptop also shuts down in BIOS when on battery power and I have already installed another SSD to exclude Windows (I had removed the original SSD when purchasing to store it safely if I needed the original image).

Anyone have an idea ?