I never replaced an UPS battery with something else other than OEM.
For Cyberpower CP1500EPFCLCD, that uses some Leoch SLA 12V 9AH batteries, can I use AGM ones? Or gel ones?
I was too ignorant to this topic until now, because I had just 1 APC. Now I have 12 CP ones. 
I don’t know much about battery types and if you can switch between them…
I read in CP specs that it charges with 0.6A.
OEM battery:
Aftermarket:
Amazon akku… battery:
12V 9Ah is a pretty standard battery. There are also 7.2Ah batteries with the same physical size.
Something like a CSB XTV1272 or EVX1272 should be good.
I have tried CSB HRL series and was disappointed - they do not last as long as EVX or XTV. For some reason HRL start self-discharging rather soon.
“Normal” batteries are designed for low temperatures and do not last as long, especially in higher temperatures. For example, your UPS does not seem to have a fan, so it’s probably pretty warm inside. You should look for “long life” or “high temperature” batteries, as much as you can trust the manufacturer to be honest.
I primarily use CSB as that’s what my local store has (of the good manufacturers). Another batteries I have tried and they lasted long was EnerSys DataSafe series.
Both models that I have, CP1500 and CP1300 have fans; they start when the AC drops, and they run a few minutes more, after AC is restored.
I don’t care much about brands, only if those technologies are interchangeables. I read somewere that AGM has a different profile for charging than other techs, but I don’t know. All the guides out there about battery types seem to be written by non electricians, with a bunch of Amazon links.
CBS makes the OEM ones for APC smart line, so they should be pretty good; but in my country there aren’t many options and Amazon dosen’t delivery too many here.
Ups manufacturers don’t make batteries. There is no such thing as “oem” battery. You was paying a lot of money for the stickier with their logo they place on the battery though. But it does not affect runtime or longevity.
Defenestrate all of them please and buy APC. I’m not joking.
Correct. Use the same type it came with. Usually it’s the cheapest one. AGMs are more expensive and will either die sooner (if used, and kept being charged incorrectly) or at thr same time (if unused, because 2-3 years of standby you would want to replace them anyway, because garbage CyberPower does not recalibrate batteries)
Again, there no technical difference. They just got a juicy deal to supply to APC. There is no difference between batteries that is worth paying for. Buy non-obnoxious ones from eBay or aliexpress, from reputable sellers. Ignore brand of batteries themselves. They are commodities.
I swap out my lead acid batteries for lithium when they die. It’s important to get one that is designed for the charging/discharging of UPS that was using non lithium. Otherwise they can be charged to 100% too often, and in the case of the LiFePo batteries they have a different voltage arc during discharge, so the “minutes left” may nit be accurate depending on how it is caculated. Ultimately not a straight 1 to 1 based on amp hours, but when you have the right kind it can last a lot longer than the old heavy batteries that tend to die every year or two and need replacing.
Reputable sellers on Aliexpress… 
Yes, I know the APC dosen’t make them. It’s CBS with APC sticker. I was reffering to them.
Cyberpower sine wave line is cheaper than APC smart line for the same capacity, and served me well. As I said, my oldest CP has 4 years, and the battery is still kicking. APC smart 750, it was smaller, true, but after 2 years to be so dead, that even the power on test fails… that’s dissapointing.
That’s the thing… from what I see on the originals from CP, I understand that they are SLA, but nothing else. Not AGM, not gel… I don’t know how many technologies there are to make a sealed battery.
So other than AGM and Lithium, which I stay away from (I saw too many things burn from Li), I can find only gel ones. I don’t see specs 1:1 as the originals nowhere. And the CP dosen’t give any details about charging cycles other that they charge with 0.6A.
I think after a month, I’ll become a guru in UPS batteries, reading all stuff about them.
Time for another guide like the Synology Memory one. 
Correct. There are reputable sellers there. Like everywhere. But for batteries — just buy the cheapest one. It does not matter.
I wonder why. But ups you buy once and use forever. Price does not matter.
Unless you have proof that APC kills batteries and CP did not — you just got bad battery in APC. It does not mean that cp are worth buying.
I have a few SmartUPS. The original batteries lasted two years (after that capacity reduced below 80%, I replaced them. Then I kept buying PowerSonic in the last decade. They lasted 2-4 years.
All my CyberPower UPs that I bought within last 5 years because they were cheap, and what could go wrong, ups is an ups — are now rotting in the landfill, because they are money and time pits and don’t work.
Also, do you have specific need for sine wave? Value in SmartUPS is not sine wave, but proper battery management, calibration, reporting, and control (via SNMP and otherwise). The key here is “proper”.
They demonstrably don’t honor offdelay parameter. It documented all over the interwebs. These does not mesh with “served well”. Maybe as a stool or a paperweight. Or maybe you never lost power, or did not otherwise notice that their configuration is broken by sheer coincidence.
In my opinion CyberPower ups have negative value, nobody shall buy them on merit.
A long time ago I bought a big (for me at the time) UPS - APC SmartUPS 2200. It uses 4x12V 18-20Ah batteries. After some time the batteries died, so I bought the cheapest ones from my local store. Those batteries lasted a year. After that I bought CSB EVX series (I wanted HRL, but the store did not have them in stock) - I paid about double for them, but they lasted about 10 years.
That UPS has a fan, but it only runs when the batteries are charging or discharging. Otherwise inside it can get pretty warm, especially in a room with no AC. Even now it’s 31C inside that UPS.
I later got another, very similar UPS, and modified it so its fan runs all the time (faster when charging/discharging, slower otherwise). Both UPSs are right next to each other and the temperature inside this one is 23C.
Room temperature is 19C in the mole of the room and about 13C near the floor (where the UPSs are, but they are near each other so they probably warm each other up a bit).
So yeah, there is a difference between batteries, even between different series from the same manufacturer. I have tried EVX, HRL, XTV and GP (these are the cheapest) from CSB and they behave differently.
Some modern PC power supplies may not like modified sine. Also, at least my SmartUPSs have real sine.
Obviously. My point was that the difference is immaterial for standby use case like in UPS.
To your anecdotal usecase — I would have replaced them at year four no matter what, as a matter of policy.
Defenestrate them too. Those are shitty power supplies.
The difference between sine wave and a rectangle most UPS produce are higher order harmonics. The same harmonics a power supply is supposed to suppress to produce DC on the output and protect equipment from transients and surges.
If the power supply does not like harmonics — it is not designed properly and won’t protect your equipment and should not be used.
Furthermore, sine wave is important for things like AC motors. In PC power supplies that sine gets immediately rectified anyway, (and by the way, massive amount of harmonics are generated in the process — the energy is pumped at peaks of the sine wave). Those are flattened and suppressed by LC and RC filters in the supply.
That said, industrial power supplies do rely on the power being sinusoidal for power factor correction — unlike home users who pay for consumed energy, enterprises pay for volts times amps: as they can easily overload the grid while consuming 0 watts. But this is irrelevant in the context of UPS discussion
They don’t 
unless there is a motor inside — they generate simulated sine wave. An approximation, can be as close to single frequency as needed. But it’s not a real sine — it’s a rectangular noisy signal, albeit well filtered. You can open it up and you’ll see a bunch of mosfets inside. Good UPSs will have beefy coils and capacitors. Bad ones — flimsy ones.
Most PC power supplies has Power Factor Correction, which tries to reduce that. However, if the PFC circuit is not that great, the power supply can refuse to run from a non-sinusoidal source. AFAIK PFC is mandated by EU law for power supplies above a certain power rating, but the rating is low enough that all PC power supplies have to have it.
I dislike active PFC, because I have seen a few PC power supplies blow up and short the mains (tripping the breaker) when the big capacitor on the hot side fails.
Maybe it has changed, I don’t know, but when I was reading power supply reviews, the reviewer was testing them on a cheap UPS to see how they behave and some failed. Old style power supplies without PFC (or with passive PFC - just an inductor) are better in this regard - you could probably feed them DC and they would still work.
I have seen a server power supply refuse to run from a generator - I guess it did not like the voltage and frequency variations. An on-line UPS in the middle (or a different generator) solves that problem, but at the time it was “fun” when one of our clients found that out.
Good enough that motors don’t complain. Even daisy chaining one UPS after another works.
My Smart-UPSs have big transformers inside (older design I guess), but I have UPSs with transformers that output square wave or modified sine that makes transformers and motors buzz.
I even have a small 300W inverter that produces true sine (or as close to it as possible)
I the output has a few percent THD it’s not a problem, the problem can be when a UPS outputs square wave or a “modified sine” or whatever it is called that has a lot more than a few percent THD.
I don’t now, having to replace batteries after a year vs keeping them for 10 years (in both cases I replaced the batteries when UPS self-test failed) seems like a big difference to me, especially when the price is not 10x for the better batteries.
I have a few small UPSs and one big UPS (40kVA) that uses 60 batteries (possible to use it with 120 batteries as well), so I want to save money by buying batteries that last long despite the non-ideal conditions (it’s pretty warm in the summer in the basement where that UPS is). If I had to replace them every year, it would not be fun, even if the batteries were half the price.
I’ve got an official response from Cyberpower:
Any VRLA battery will work as long as the spec is the same as below:
Nominal Voltage: 12V
Capacity: 8.5~9AH
Connector Type: Faston Tab T2-250
Dimensions:
I decided for Ultracell UXL9-12. It has the same specs as the original one and has 12 years life.
One good way to decide which lead acid battery to buy is to look at weight.
The more heavier it is the more lead it contains and there are significant differences between the same battery capacity and weight.
Then there are datasheets - reputable brands will show you lifespan vs operating temperature, capacity vs discharge current charts etc., shitty brands will have no such thing.
I also wouldn’t buy the 9Ah battery for UPS application as that will generally have shorter lifespan than the 7.2Ah one.
Why is that? Is couterintuitive. I don’t say you are mistaken, I just want to understand.
The datasheets from the same manufacturer I saw always stated lower lifespan for the 9Ah battery compared to the 7.2Ah one. If 7.2 was 10 years, the 9Ah was 5 for example, same dimmensions of the battery of course.
My understanding is to increase the capacity you have to cram more surface area into the same space, meaning the lead plates are for example thinner, or their design is slightly different. There also might be slight changes to the electrolyte, and all these changes might and I believe will negatively impact the battery lifespan.
My take on it is the standard was 7.2Ah for a reason - a compromise between capacity and other properties, and then someone came and changed it to gain extra capacity, but reduced the lifespan.
Yeah, this makes sense. I wondered why they make 7.2AH too, instead of only 9AH, at the same dimensions. But for the Ultracell UXL series, they specify 12 years, no matter the capacity. I go with those because the UXL9-12 model has the same specs as my original one and it has the same price as the UL9-12 standard one; and the stocks are higher in my country than the standard model. If they last 4-5 years like the originals, I’m verry happy.
I set my NASes to shutdown the UPS after system shutdown and only 5 min of running on battery.
Higher capacity → larger surface area → thinner and more prone to sulfation plates.
