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Is it worth buying a replacement battery for a UPS or better to buy a completely new UPS? I have heard a UPS is never the same after the original battery dies and is replaced.

Is it OK to use a third party after-market replacement battery or should you always go with the original manufacture's replacement battery?

My question is specifically about the APC XS 800 (a small business/home UPS) but I'm interested in your thoughts about UPSs in general.

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up vote 14 down vote accepted

I've never heard about replacing a battery causing the UPS to never be the same. The only UPS units that I've ever seen are just sealed lead acid batteries that wouldn't cause issues with the UPS electronics unless they weren't specced right (proper voltage and amperage rating). I've used APC and third party batteries and had luck with both. The third party batteries are generally cheaper so that is the way I would go. You don't need to replace the UPS unless there is something inherently wrong with the UPS electronics.

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+1 for just replacing the battery. The UPS itself shouldn't need to be replaced as often as, say, a workstation. I haven't had good luck with 3rd party batteries though...the common issue with them seems to be swelling. The battery will go bad and I can't get it out of the UPS. Has happened with a couple different 3rd party battery mfrs, but never with APC brand. – user78940 Jun 12 '11 at 17:05
If you do buy 3rd party replacement batteries be sure they're equivalent sizes. I recently shopped for a replacement battery for an APC 1300VA UPS. All the 3rd party batteries I saw were called "compatible" but listed an capacity (amp hour?) rating equivalent to the low end 1000VA model in the family. These batteries were also sold as compatible with the 1500VA model that was the top end model in the family. I assume they'd work as long as you weren't maxing your UPSs load out; but you'd only get the run time of the low end model. For an equivalent rated battery I had to buy genuine APC. – Dan Neely Jan 16 '12 at 19:21

I would say that it's definately worth buying a replacement battery. Not to mention is probably better on our environment if you're only changing the battery and not the entire unit.

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+1 A replacement battery from the original vendor should a don't care to the UPS electronics. Of course, my vendor is currently recommending that I replace the entire UPS (it's oooold). – Bob Cross May 17 '09 at 18:32
I agree- the controller is solid state, so I don't see how a legit replacement battery could possibly cause trouble. – Tim Howland May 18 '09 at 0:34
Except that they age and get dusty like everything else. 3 UPSs that we replaced batteries in burned out (with sparks and smoke) within 3 months of the battery replacement. – Jay R. May 19 '09 at 18:36
3 months later? Time for a new UPS vendor. We've done several battery replacements with no issues. – kmarsh Jun 29 '09 at 12:19
If the UPS was not abused, and less than 10 years old I agree. Older UPS controllers / inverters may be less efficient than more modern ones, but you need to consider the specifics in the particular case. – mctylr Mar 6 '10 at 22:39

We've replaced the batteries in our oldest UPSes 3 or 4 times, and I don't see any reason not to keep them going for a while longer. These are a 5U form factor, 3000VA, 120V input and since it doesn't look like they're available any more, I hope they keep running for a while.

We have about 8 of the smaller 1200-1400 VA SmartUPSes and over the years the electronics on 2 of them have failed, but other than that we've replaced the batteries in those a few times as well.

I've bought 3rd party SLA (sealed lead acid batteries) for my electric bike, but it never occurred to me to look for UPS batteries from those suppliers. Next time we need replacements, I'll look into it. As far as I know, there aren't a lot of secret design techniques for SLA batteries, so I'd expect batteries with the same ratings to be just as good no matter where you buy them from.

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The batteries in UPSes are almost universally completely standard size and spec lead-acid batteries, as they are cheap and easily obtained. The UPS manufacturers just like you to buy from them as they charge a lot more. – David Gardner Jun 29 '09 at 15:05
We've had a few CyberPower UPSs that have silenty failed on the charging end. Brand-new batteries replaced just months before and we got just seconds power out of them when the building main popped. They are 1000w AVR units, but the load was never showing anywhere near peak and so shouldn't have been using battery power to supplement. – Magellan Jun 15 '11 at 14:54
This may mean nothing. As in: you got 2 bad loading Systems - good. Bad luck ;) – TomTom Oct 7 '12 at 14:54

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