Replacing UPS battery: From 12V/7Ah to 12V/9Ah

JEDI

Lifer
Sep 25, 2001
29,391
2,737
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i have the cyberpower 900VA ups. the batteries finally died after like 5yrs.

i replaced the two 7ah OEM with 9ah ones.

will the cyberpower software recognize that i have more capacity and estimate the runtime correctly?

(i never used the software when i had the 7ah batteries.)
 

mfenn

Elite Member
Jan 17, 2010
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www.mfenn.com
The new batteries should work fine and give you longer runtime. I don't know how smart the monitoring software is though.
 

bryanl

Golden Member
Oct 15, 2006
1,157
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will the cyberpower software recognize that i have more capacity and estimate the runtime correctly?
Not unless the UPS ran a rather good calibration test. I'd worry more about the UPS overestimating remaining capacity since batteries deteriorate noticeably even after just 12 months of use.
 

Gillbot

Lifer
Jan 11, 2001
28,830
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1001604h.jpg
 

Jeff7

Lifer
Jan 4, 2001
41,596
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I hope that box has ventilation on the backside. Charging lead acid batteries in an enclosure isn't a good idea, unless you like having hydrogen in a box.



I also recall seeing some posts by Rubycon at some point that using that kind of battery with a UPS might not be a good idea, and that they're better-suited for SLA gel-cell lead acid batteries. I'll look around quick and see if I can find the posts...

Link1
Link2 - Ah, I see that your UPS has been around for awhile, and Rubycon was involved in threads that you had seen.

Well...apparently you haven't blown up yet, so that's good. :)
 
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Gillbot

Lifer
Jan 11, 2001
28,830
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Yeah, the lid isn't sealed shut and that's also why I clearly put in the post:
I don't recommend it

I know the hazards and have dealt with them (IMHO) sufficiently to satisfy myself. Plus I used it for quite a LONG time and I didn't explode. I do recommend sealed batteries for those less experienced, or purchasing proper replacements but i'm not going to stop anyone so long as they are aware of the risks.
 

Modelworks

Lifer
Feb 22, 2007
16,240
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The whole hydrogen producing thing from batteries is HIGHLY exaggerated. Hydrogen is only produced externally when the batteries are overcharged. Consider this, the battery requires water to stay functioning. If the battery converted that water to hydrogen and it leaked out every time it charged then the battery wouldn't last long because it would dry out.

The hydrogen warning is there for legal reasons , just like alkaline batteries say they will explode, and lithium batteries have a fire and explosion warning.

To the OP, the UPS will not care about the new capacity unless you calibrate it for the new battery. You need to read up on your model to find out how to do the new battery calibration.
 

Rubycon

Madame President
Aug 10, 2005
17,768
485
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The whole hydrogen producing thing from batteries is HIGHLY exaggerated. Hydrogen is only produced externally when the batteries are overcharged. Consider this, the battery requires water to stay functioning. If the battery converted that water to hydrogen and it leaked out every time it charged then the battery wouldn't last long because it would dry out.

The hydrogen warning is there for legal reasons , just like alkaline batteries say they will explode, and lithium batteries have a fire and explosion warning.

To the OP, the UPS will not care about the new capacity unless you calibrate it for the new battery. You need to read up on your model to find out how to do the new battery calibration.

Pay close attention to bolded red part!

Be sure that your UPS is NOT overcharging your batteries. Chargers programmed specifically for SLAs tend to overcharge flooded batteries. At the very least check ventilation and water levels frequently. A dry (flooded) battery is a dead battery...