A UPS ( Uninterruptible power supply) that's my plan for my home's Network
though mine needs a new battery it used to give me about 30-35 minutes of wifi
during a power outage which was handy. just think about what all you want to run off of it
and get a UPS that will suit your needs.
and remember with a Backup battery you want your settings to be in, " Power Saver Mode"
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