

unless the data is off site, its not truely a backup
Two is one and one is none. No matter if it’s offsite or on top of your main server. Also 3-2-1 is an industry standard for a reason. Plus unless you test that you can actually restore your backups they don’t really exist (also known as Schrödinger Backups).

As others have said, this is something software can’t do, so there’s no linux tools for it. There is charge profiles which may help in the long run, similar than what your smartphone likely has. But that absolutely requires that your charger outputs the voltage and current your laptop requires.
If the physical connector ‘kind of fits’ I personally wouldn’t use it, even if the voltage was correct as it’ll likely damage the connector on the motherboard and then you’re looking for a much more complex repair. Laptop power bricks are pretty cheap.