How to organize self-powered pc in an apartment?

Question

Batteries

In recent years, cases of prolonged blackouts in the summer have become more frequent. I work remotely and this greatly interferes with the work process. Therefore, the task arose of organizing an autonomous power supply for a non-gaming pc (650 W power supply) and a router in the apartment for about 5 hours.
Generators fall off because of a lot of noise. Inverter + battery from KAMAZ - also disappears, it is not clear where to get a current of 20 A for charging.
Can you tell me, please, what other alternatives are there?

Answer 1

there are no household options for 5 hours.
inverter + battery from KAMAZ is a great option, current 20A is the maximum recommended. in general, you can assemble a good craft from Chinese things, especially if the functionality of an uninterruptible power supply is not required.
uninterruptible power supply with an external battery - requires improvements and checks of the UPS itself, which will be a donor.
from the exotic, these are motherboards and power supplies with an input from 12 / 24v and an external battery to exclude 12--> 220--> 12.