Laptop using Integrated GPU instead of Dedicated GPU when battery is taken off.

My laptop is lenovo thinkpad e560 and as the title says when I use the laptop with the battery removed and directly connected to wall power it never uses the dedicated gpu (amd radeon r7 m370) instead it uses the integrated (intel hd graphics 520) for everything even when I use the highest battery settings and the highest preferred settings in the amd program settings. I take out the battery because ive been told that its not healthy for the battery to always be charging when I use it home plugged in 24/7.