What is the model number for the batteries? And, I need 4?I have that same ups, yep its old and to replace the batteries last year was around $100. Not apc branded batteries though
I have the Ecoflow River 3 Plus and it does work well as a UPS. It supplies power to both my BI Server and an older Dahua NVR608-32. I paid $180 for it new, direct from Ecoflow. It has not failed me during any of the power blips and short outages in the last 2 years. What I like about it is the batteries should last much longer than the old lead-acid gel cells used in most UPS's. What I don't like is they never released a true PC or Mac based software package that would automatically shut down a computer after a specified time period like APC or Cyberpower does. Still, if there is an extended outage and the batteries get run down completely, at least I don't have to worry about having to replace batteries any time soon. If this occurs with a Gel cell UPS, it could easily ruin the batteries. Another nicety is the app Ecoflow has will notify me of an outage if I'm not home. With that I can VPN in and shut down my gear remotely if the outage is extensive. And, you can easily add additional capacity to the River 3 Plus with external batteries. Just a thought.I hate buying traditional UPS. The lead acid batteries they use have very low capacity and don't last long in terms of years before they don't hold a charge anymore and your stuff shuts off instantly when the power goes out. And speaking specifically about Cyberpower, the electronics have had a horrible failure rate for me. If you want a traditional UPS, I'd suggest any other brand.
When I need a new UPS I buy Ecoflow batteries instead. Especially now that they have some newer models with 10ms switchover time meaning they can act as a UPS for desktop computers and stuff of that nature. They use lithium iron phosphate battery chemistry designed to last 10+ years, and have way more battery capacity than anything you'll find from the likes of APC at a comparable size or price. You do need to add your own power strip though. Ecoflow batteries don't have a lot of power outlets on them.
River 3 Plus is the cheapest model I'm aware of with 10ms switching time.
It will do up to 600 watts cleanly and run that for perhaps 20 minutes on its battery. Expect more like 40 minutes with a 300 watt load. Compare that to the roughly 1 to 8 minutes you would get from a traditional UPS costing a similar amount.
For a lot more battery capacity and watts, the next best deal I know of is Delta 3 Classic for around $400. It has a full kilowatt hour of battery capacity and can power pretty much anything, even an air conditioner. I'm using that to feed my very power hungry gaming PC that was too much for a mere 900 watt output 1500va UPS from Eaton.
They use lithium iron phosphate battery chemistry designed to last 10+ years, and have way more battery capacity than anything you'll find from the likes of APC at a comparable size or price.
And they are designed to not catch fire, even if they are directly shorted. One of their many design advantages.LFP batteries have been proven safe for years. People with solar powered homes use 10's KW of LFP batteries in their home without issue. LFP do not have the fire risk as the other lithium batteries you hear about starting fires.

What is the model number for the batteries? And, I need 4?