My UPS (APC) has faulty batteries (again). 3 years old, already fried. I don’t mind the poor capacity of the PbAc batteries but this life cycle is horrible (2-3y tops).
Can I replace them with equivalent LiFe batteries like the ones you find on Amazon and such with the same form factor?
Or are there LiFePo4 UPS available in Europe?


Not without changing the charge controller as others mentioned, you’ll basically be diy’ing a whole new ups.
Which you can do, and this is a great example (from a few years ago):
https://static.xtremeownage.com/blog/2021/portable-24kwh-power-supply--ups/
You’ve also got options like Eaton for lithium-ion UPSs, keep in mind that they are generally better than APC or CyberPower units and will cost more. As far as your batteries go today, thats (my opinion) the likely reason for the short life - you should get 5 years out of them unless your power is really unreliable. The charge controllers in the small UPSs from APC IMO aren’t great.
I’ve got all lead-acid, but most of my UPSs ive done some degree of work on (just used the casing and swapped the guts, full diy, and a better rack-mount unit I made my own external battery pack for), and they all have gotten 5 years or better so far (about 12ish years in at this point).