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Why nobody reconditions a UPS battery

smilem

Member
Hello, I tried to find some information why nobody tried to recondition not dead (no sulfation) but used CSB UPS battery for example the common type 12Ah.

You could measure the electrolyte with a reflectoemter, you need only 1 drop.
Then you could add water or acid to it.
The actual acid gravity is not specified, but you can check new battery and find it that way.

Given the fact that common death of UPS batteries is dried out batteries why nobody reconditions them? No discussions on forums etc. Are people too stupid to measure the the acid with a reflectoemter? Or there are other problems?
 

jpanhalt

Well-Known Member
Most Helpful Member
Given the fact that common death of UPS batteries is dried out batteries why nobody reconditions them?
Are you suggesting that the acid simply evaporates and leaves a dried battery? How do you know there is no sulfation?

Are people too stupid to measure the the acid with a reflectoemter?
BTW, the instrument you are probably thinking of is called a refractometer, not reflectoemter, assuming that you mean reflectometer for the latter.

Can you explain how you can get a low acid concentration in a "dried out" battery that is not sulfated. What would you do to cure that situation? Where did all the acid go?

John
 

tcmtech

Banned
Most Helpful Member
I think it has more to do with the fact that a new UPS battery is rather cheap and given its application of keeping computers running and information on them undamaged during power outages people would rather spend the money and have a new trustworthy battery doing what its supposed to do when its supposed to do it and for as long as it supposed to opposed to leaving it all up to a hopefully fixed but likely questionable old battery that has once failed.

That's my thoughts on why.

Plus I don't know a single person who owns a reflectometer either including myself and I have a lot of tech toys!:eek:
 

smilem

Member
Are you suggesting that the acid simply evaporates and leaves a dried battery?
The mixture of acid/water evaporates yes. Remember a single bad cell can make battery bad.

How do you know there is no sulfation?
You measure battery resistance with special meter (very expensive), or use simple multimeter and a load, then use formula to calculate internal resistance.

Or you use a smart charger, I have CTEK that measures and the sulfation. IF the charger goes to step 2 and skips step 1 the battery is not sulfated. Given the fact that most UPS batteries are overcharged I see no reason that they can get sulfated.


BTW, the instrument you are probably thinking of is called a refractometer, not reflectoemter, assuming that you mean reflectometer for the latter.
Yes perhaps refractometer, sorry my native language is not english.

Can you explain how you can get a low acid concentration in a "dried out" battery that is not sulfated. What would you do to cure that situation? Where did all the acid go?
Well I did not say you can always get low acid or low water concentration. If battery plates are OK, then you need to measure and see what to add I guess.
 

jpanhalt

Well-Known Member
Most Helpful Member
Your fundamental premise that sulfuric acid evaporates from a battery is flawed. The water evaporates. The sulfuric acid either remains as an increasingly concentrated solution, or it more likely forms sulfates.

Here is a chart showing the vapor pressure of sulfuric acid in aqueous mixtures:

http://www.electro-tech-online.com/custompdfs/2013/02/Sulfuric_Acid_Partial_Vapor_Pressure_20.pdf

Even at 60 °C, the vapor pressure of concentrated sulfuric acid is <0.0001 mm Hg. That is the reason that sulfuric acid can be used in desiccators as a powerful dehydrating agent without contaminating the materials being dried.

If you ever see a dry lead-acid battery, it is either sulfated, the sulfuric leaked out, or it was never filled.

As for why back-up batteries are not rejuvenated, I suspect you are confusing their routine and/or scheduled replacement with replacing the batteries because they are bad. Since they are a critical element in many systems, it is simply prudent to replace them before they go bad.

There is a small market for such batteries, and of course, they can also be recycled. One of the people I fly model airplanes with has access to batteries that have been removed from back-up supplies in the course of normal preventative maintenance. They are still quite usable for non-critical applications. We use them to start our model engines. There are lots of other uses for them.

Oh by the way, tcmtech, I have both a refractometer and polarimeter on my mantel.

John
 

MikeMl

Well-Known Member
Most Helpful Member
How do you add liquid to a gelled electrolyte? Even if you do, how do you get it to diffuse uniformly throughout the matrix. These things are called "Sealed Lead Acid Batteries for a reason....
 

killivolt

Well-Known Member
As for why back-up batteries are not rejuvenated, I suspect you are confusing their routine and/or scheduled replacement with replacing the batteries because they are bad. Since they are a critical element in many systems, it is simply prudent to replace them before they go bad.
Exactly. At the University we simply change them, then they go to the recycle bin.


then propose how you would recondition them. Save the plastic?
When you do you will have saved a ton of money and made a couple yourself:rolleyes:
 

tcmtech

Banned
Most Helpful Member
Go on ebay and buy one. LOL
So I should buy a $25 tool to find out if I can fix my $20 battery? :confused:

The problem with most batteries when they get baked dry is that they also tend to crack the plates and loose a lot of their plate surface area to permanent physical degradation and damage due to sulfation build up.

All the water in the world wont fix that.


Am I too stupid to try and fix a UPS battery? NO!

I know better because I know that 8 out of 10 are not worth fixing or wont last after the fix and the two that may work will still never be 100% reliable or up to full working capacity. :(
 

Nigel Goodwin

Super Moderator
Most Helpful Member
I know better because I know that 8 out of 10 are not worth fixing or wont last after the fix and the two that may work will still never be 100% reliable or up to full working capacity. :(
Yes, it's a pretty silly thread - hopefully the OP has learned why his idea is a non-starter.

The old batteries are of course recycled anyway, and the lead reclaimed to make new batteries.
 

smilem

Member
Yes, it's a pretty silly thread - hopefully the OP has learned why his idea is a non-starter.

The old batteries are of course recycled anyway, and the lead reclaimed to make new batteries.
Silly thread or not but since US air force hasn't got the money to buy new batteries and fixes them why shouldn't average joe ?
Seems like Catalysts on VRLA Batteries Save Air Force Millions of Dollars
http://webcache.googleusercontent.com/search?q=cache:CbcsoACICZEJ:www.power-eng.com/articles/print/volume-109/issue-10/field-notes/catalysts-on-vrla-batteries-save-air-force-millions-of-dollars.html+VRLA+batteries+by+adding+water&cd=2&hl=lt&ct=clnk&gl=lt

So the question is where can I get these caps of catalyst?
 

tcmtech

Banned
Most Helpful Member
Telecommunications standby battery banks are not normal UPS batteries.

They are usually a very large single cell type lead acid battery that can easily be anywhere from 150 to 2000+ Ah per cell at 2 volts with a service life in excess of 20 years.
(Just like the article in your link states.) :p

Design wise they are not anything close to a common sealed gel cell UPS battery. :(
 

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