Home Networking

If your lipo has a bms onboard just use it with the ups. That'll protect it from any charging issues I'd assume. My wife has been using 2x 9ah lipo batteries in her cyberpower ups for almost 3 and half years now. The last rundown I tried was in June and it ran a little over 30 minutes while web browsing running her pc, the modem, and her fish tank pump. It went untill it hit the sla battery cut off which is 10volts I believe. The original battery was about 4yrs old and wouldn't even run 10 minutes. It would die before the power would be restored. That was at our old house though, our current one doesn't have brown outs. Occasionally we have power surges.

There is an issue with using lithium battery in UPS. AFAIK all types of lithium batteries on the market now, They don't like to be staying fully charged all the time. That's why lead acid batteries and Ni-Cd batteries are still used for providing emergency power

APC used to sell a consumer lithium UPS: here's the price history. $270 for something about the capacity of the $50 lead acid equivalent. Looks discontinued now. They sell a lot of rackmounted options but they are all expensive.

Lithium is advantageous for repetitive discharge and recharge cycles which is useless for a UPS installation with a reliable power source. The cost/capacity of lead acid wins out.

Cheap and Lithium are not two things I want together

Lithium batteries are about weight, so they make perfect use for portable uses (like portable power stations). Most UPSes get installed once and stay put until decommissioned. The added expense of lithium batteries makes no sense.

Most of your store bought UPS last a few minutes to an hour, mine that I made myself lasts 5 days at 24/7 usage, charges back up with a 375watt panel if there is sun in less than 5 hours and has a 10 year warranty on the battery that is a Life4po 120AH battery connected to a wall charger and a pure sine wave inverter so my equipment is running on even cleaner power than the grid. In a power loss I am already technically plugged into the battery, so when power returns the lithium charger starts back up or if it’s a few days without electricity my solar panel will do the work.

All for 900$

Compare what you get for 900$ from a store bought UPS, is maybe a few hours run time. But at least it fits into a rack right? Who cares if it’s rack mountable or not, I want power and durability not a plastic box with a shitty lead acid battery that will have a 1 year warranty on it.

There's also the fact that Lead Acid don't catch on fire when they go bad like the Lithium based cells do.

Was asking myself the same question.

Another annoyance is that all products on the market are labelled in VA and not Wh, which makes it very difficult to compare and understand how long they'll last at a 20W draw of the standard networking equipment.

Cheap and lithium do not go together. Have you seen what happens when lithium batteries fail?

The answer comes down to cost. LiFePO4 batteries have enough capacity that they can be held at 80% and still beat SLA on capacity. The problem is that LFP wins on gravimetric and volumetric energy density; two metrics that aren’t particularly important in the context of a UPS. It’s a large brick that sits on the floor.

I have a regular UPS for my server+NAS, and a small lithium one (pocket sized) for my low voltage things (basically all my network gear, sans POE). It was inexpensive and works fantastically. The best part was erasing 4 power brick transformers from my network closet and replacing them with just a 5V barrel cable directly to the UPS. I think it's highest output is 12V which runs my 24-port switch (I think, maybe my router).

https://www.amazon.com/dp/B07WLD32RP

Probably in a dumpster fire somewhere

Simultaneous charge and supply circuits cost a fair bit to design and implement.

It's a lot cheaper and profitable to build a basic 'brick' that can be sold to hundreds of thousands of 'phone users rather than a premium product for a few computer folk.

I’m using a UPS that is plugged into a EcoFlow power station which uses LiFoPO4 battery

https://imgur.com/a/qbqE8e8

Most lithium battery ate not full lith It lithium poly etc type. Most none car battery are lead calcium

Lead acid is very cheap, electrically very easy to charge, safe and actually very recyclable.

That said, yes LiFePO4 is really coming down in price. In telecom DC power systems, I've been using 48V packs in some situations because the cost difference between lead acid and lithium is only about 20-30% more.

The big benefit of lithium is the weight and amount of cycles you can get out of them. The longer service life is also a factor, but they're most useful in situations where you are cycling a lot (EVs, solar power systems) but UPSes aren't really taking advantage of that unless you live in a particularly bad area for power, the UPS's poor quality charging will likely damage the battery more than the cycling. It's also nice that lead acid is so common that you can often just walk into most battery / auto parts stores with the cell and they'll have something that will fit.

EDIT: I forgot to mention! There are some cheap 12V lithium UPSes out there for powering things like modems and WiFi routers. These are often a lot smaller than traditional UPSes, but since they're keeping everything on DC power can mean you still have a decent amount of runtime.

I'm just re-using my APC Smart-UPS 750 and a pair of batteries like these. Allegedly the BMS / charging circuits in them are designed to work with charging systems that generally charge up 12v lead acid batteries. The pair of batteries I ordered have the exact same dimensions as the lead acid batteries they're going to replace, and the same connectors in exactly the same location.

I've watched a number of videos on YouTube with folks that have done such conversions (using a wide array of UPS models). Even watched a video where a guy did a short circuit test (the battery he used failed miserably, but didn't catch fire). The cable on my UPS has a built in (and replaceable) fuse, so I'm not worried about an issue with the UPS pulling far more amperage than it should be. Of course, that fuse won't do much good if something inside the battery itself fails, but I suppose that's what home owners insurance is for. :)