Faulty (swollen) UPS batteries

Discussion in 'Electronics & Electrics' started by Meddish, Jun 6, 2008.

  1. Meddish

    Meddish Member

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    hey need some help with a small battery problem,

    i bought a UPS from Ebay (i know i know no ebay jokes) read the listing said it was tested, thats good enough for me, means it works, if the batterys need changeing thats OK i can get batterys

    but my problem the batterys have swollen, and now will NOT come out of the UPS cage... so im wondering guys any suggestions on HOW to get these batterys out
    PICs speaks 1000 words

    [​IMG]

    [​IMG]

    a local battery guys has told me to take a hammer to it, this i dont like the idea of as all the UPS circuts are still gonna be attached to the cage (as i cant get the batterys out of the UPS)

    lastly ive also been told the batterys have done that because they have been overcharged, anyone know if this is ture or otherwise
     
  2. mshagg

    mshagg Politburo

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    Batteries can swell from both discharge and charge. The chemicals create gasses when being charged and when being discharged, cells have vents to prevent a build up... if vents fail then battery will swell.

    Most likely from charging, as something has to be wrong with the current draw to get gas build up like that from discharging.
     
  3. mhgarage

    mhgarage Member

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    Wow.
    Keyfiles and cut those metal straps?
     
  4. Cypher

    Cypher Member

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    Be thankful they're only swollen and not split like mine were, definatly don't try to use the ups while the batteries are in this state.

    As for getting them out, you could try using something like a G-clamp and some blocks of wood to press the batteries back into a more normal shape, tho this might also result in the batteries splitting which is bad...

    If things do go pear-shaped and you split a battery put it/them into an old icecream container, when it happened to me I was told this should contain the spilt acid.
     
  5. cbb1935

    cbb1935 Guest

    How do they normally come out (if not swollen)?

    Looking at the size of them swollen or not it wouldnt come out up the metal bar.
     
  6. Meddish

    Meddish Member

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    2nd pic they slide out forwards (towards the cam)
    (first pic acidently upside down)

    didnt think of clamps that might work....
    so far im thinking about drilling into the under side (there are 4 neat holes under the UPS) then bucket and clamp the batterys down so they can be pulled out....

    they are UPS batterys so they should be sealed lead acid batterys

    the 'ebay' guy has my number hes gonna call me.....
    so far im not so happy... $160 or so, for a UPS that im gonna have to spend another $100 on batterys to get it back up & running...
     
  7. Symon

    Symon (Plugging your Socket)

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    From the pics it looks like the only part of the frame that is stopping you is the two tabs on either side in the middle of pic #2. My vote goes for either bending them out of the way and then bending them back, or get to em with an angle grinder.
     
  8. 2xCPU

    2xCPU Member

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    A couple of points:
    1. Looking at the distortion of the batteries, I'd say there was heat as well as pressure involved in distorting the batteries.
    2. The batteries are not particularly old (judging from the branding).
    I come to the same conclusion as mshagg and believe the UPS is overcharging the batteries. Replacing the batteries may not be long term solution.

    I think I'd talk to the seller and ask (politely) how he feels about it.

    Can you remove the 'T' bracket in the second pic? (I can't quite make out how the legs lock-in in the first pic).

    2.
     
  9. Meddish

    Meddish Member

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    ive contacted the seller, they are gonna call me,
    as i said the first pic is upside down, the T bracket is the frount 'pull' section that lets u remove the batterys, this connects to the cross sections on the first pic

    the biggest problem with the batterys is they have expanded so much there is no way in their current state they will pull forward past the tabs, (bent or not)
    my only option is to get the batterys back to their original size and then from there pull them out normaly
     
  10. Odje

    Odje Member

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    I have had a similar problem with a 2nd hand UPS, but I obtained it knowing the working state was unknown. Thankfully the battery surrounds could be full dissembled to get the battery out. The construction was all held together with screws. It was a real PITA as I had to take absolutely everything apart to get all the brackets out. while doing so I noticed a diode on the PCB which was charcoaled, so replaced that. A new set of batteries she was up and running.

    Maybe you can cut out one of those brackets and replace it with a new piece of metal pop riveted or screwed in afterwards?
     
  11. Meddish

    Meddish Member

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    thought about cutting it, but i found the batterys are also held in @ top & bottom, as well as the cross brace in the middle

    id have to cut @ least two of them and then they MIGHT come out
    battery replacment should be here today, if it works im gonna find a way to get the batterys out, then take it from there
     
  12. Odje

    Odje Member

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    The UPS that I acquired had non user changeable batteries and it was a massive PITA to change batteries. I learned about the massive PITA after finally being able to get to the old batteries, let along being able to take them out cause they were swollen. I decided that I never wanted to do that again so I drilled two holes on the side and ran the battery leads outside the case. Now the new batteries sit external to the case.

    Although I eventually got the old batteries out, you don't have to if you use an external battery bank.
     
  13. Meddish

    Meddish Member

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    this also has a spot for external batterys, but id like to get these ones internal, if all else fails ill build a box and run them external

    the good news is i got some batteries yesterday fully charged and seem to work, the 'battery guy' said the brand that IS in the UPS 'long' is crap so one cell proberly died/shorted and cased the whole lot to not reach 'full charge' so they UPS doesnt see the batterys as charged, it keeps chargeing over & over causeing the original batterys to blow up.....
    nough said

    tomorrow rip the old UPS apart and thow some batterys out!
     
  14. 2xCPU

    2xCPU Member

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    Sounds promising, but I'd check the terminal voltage with a multimeter to be sure.
    Have you tried squeezing the batteries yet?

    2.
     
  15. Meddish

    Meddish Member

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    ok i have one working UPS

    squeezing batterys didnt work, well it did and didnt, after takeing the clamp off, the batterys would reswell somewhat,
    i ended up getting pissed off and giveing the wife the drill (shes good @ destorying things) end of project is shown below

    [​IMG]

    [​IMG]

    [​IMG]

    all the dust is the batterys internals, long story short battery had turned to dust, IF YOU EVER have to do this, drill the batterys to make sure they are dust, then take a angle grinder/dremal cut thru the plastic outside caseing
    take chisle pop off outside caseing, then take plyers and pull out anything u have to, to clear the metal houseing!

    [​IMG]

    [​IMG]

    back up running and chargeing now
    little worse for ware but working (even after i resolder then frount LCD back on, (sorta hit the wires with the hammer when i wasnt in a good mood!)
    now to find some software!

    Total time 3 Hours destroying & washing myself up, about another 20min soldering, proberly gonna need another hour or two to clean up the garage!

    now after its fully charged ill plug it into my server and see how much battery life we do have
     
    Last edited: Jun 12, 2008
  16. Meddish

    Meddish Member

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    BTW i wanted to ask the electronics experts, if im measureing across the 48V battery termals what voltage should i be reading? ive been told it should be 56V (ie 2V drop across each battery for four batterys total) when charged, and higher when chargeing.... is that right? or are these new batterys gonna balloon like the last ones?

    so what voltage should it be when
    discconnected? (this should be 48V i guess)
    fully charged & connected to the UPS?
    and charging?

    thanks again guys!
     
  17. Goth

    Goth Grumpy Member

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    When fully charged, somewhere around 48 to 56V, maybe 56V when you first take it off charge. 56V when it's charging the battery is OK.
     
  18. Odje

    Odje Member

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    2.1V per cell, 24 cells in a 48V pack. Open circuit voltage when full charged would be 50.4V. Typical float charge voltage is about 2.3V per cell. So you should be reading close to 55V while under charge.
     
  19. Meddish

    Meddish Member

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    56.6V when fully charged, 53-52V when running off the batterys (UPS unpluged)
    and from memory about 48.x Volts when running disconnected from UPS

    ok so now i know my UPS is gonna overcharge my batterys, what to do next? from what ive read my batterys are gonna be stuffed in 2-3 years, so i could just live with it and worry about it in 2 years, But could i put a [Insert name of something here] to cause a Voltage Drop bringing me back inline with what the UPS should be putting into the batterys yes/no?
    if there is something what could i put in? i know LED's cause a Voltage drop but a LED woulld also blow up... so what other options do i have?

    EDIT: ive chatted to a supplier that deals JUST with UPS's he is gonna check his arcives and see if he has a wireing diagram, if i could get one, would that help some expert out there help me fix it?
     
  20. 2xCPU

    2xCPU Member

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    On a UPS of this size, there could well be some sort of adjustment to fine tune the cut-off voltage.
    You could start by looking over the PCB for any trimpots and try to read any labelling, but remember one thing - there will be high voltage on the board.
    You need to disconnect the batteries and give the board plenty of time to discharge before handling it.

    2.

    edit: what model is it?
     

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