is it possible to add a DS li-ion accumulator to DMG Gameboy

I got an old gameboy that i am applying some mods to.
I also have a broken Ds (screen cracked off) whichs battery i want to implant into my DMG.
I am not very familiar with how accumulators work,
So my question is if it is possible to add a DS accumulator to an
old DMG gameboy and if yes, how it is done?
As far as i know there is some safety board which shold be in every accu to prevent overcharge.
Is there anything that has to be applied to the gameboy to be able to let it get powered from a ds li-ion accu and charge it at the same time?
Thanks in advance.

Basically, you want to integrate a Li-on or Li-po cell battery and a charging circuit inside?

A workaround solution is to use the DS as a charger, making an external link from inside the game boy to allow temporary connection to the DS's battery contacts.

I did something like this a few years ago with a GB Pocket and a GBA SP...
That's what the RJ-11 jack is for.

I wanted to have everything set up in the gameboy, so all the circuitry that would be needed to charge the battery being setup in the gameboy.
but your way would be a solution.