Messy Battries

[Off grid in Tonopah]

    Could I bother you all with another question? Since I up graded my storage last Jan 07 to 24 volts I have noticed every time I do my battery maintenance (1 per month) I have a lot of electrolyte puddled on top of the batteries. I'll clean it off with distilled water and soda and dry them but next month same thing.

    I am filling them per the manufacture to 1/8" below the bottom of the fill neck. My charge rate is 80 amp's into 660 amp bank or around C10 for bulk charge. My voltage is at 28.8 for adsorption and float is 26.6.

    My concern is if I remove this amount of electrolyte every time I do maintenance I slowly lower the S.G. and damage the battery. While I know some deposit on the batteries is normal the amount I find seems a little high.

    I never had this problem for my 12 volt bank and most of the charge numbers I'm using are just double so I'm a little perplexed as to what going on. I thought of lowering the adsorption voltage to 28.6 and see if that helps but I don't want to be under charging. C10 doesn't see to aggressive for this size bank so I'm not sure if I need to slow down the bulk phase.

    The batteries live in a 12 foot deep hole under the power house were the inverter and charge controller live to keep them out of the summer heat so I haven't had a chance to do day to day monitoring as I have to open the floor, ventilate and put a ladder down. So it's not a run out and have a look affair. Any theory's  or insight would be appreciated.

    I've loaded a few pictures so you can see what I'm talking about

                                Thanks

                                Bob

[TomW]

bob;

Is it actually liquid spillage of acid? Or just condensed water? A sprinkle of baking soda would tell the tale.

"Puddle" is kind of vague. Some puddles are bigger than others.

What you have looks more damp than puddle. Hard to say from the photos with my eyesight.

If the battery is spitting out acid there is something happening thats Not Good [tm].

Mine always seem to be a bit damp on top but not even "wet" just damp. I wipe it off and flush with distilled water but it never reacts to a few grains of baking soda so I figure its just condensate.

TomW

[Volvo farmer]

Hey! I recognize those Sam's club batteries!

1/8" below the top? That sounds like way too full to me. Mine are at least 1/2" below the top. Realistically, if the plates are covered, you're OK. There's a certain amount of bubbling going on every charge cycle, and I wonder if you just don't have too much fluid in the cells and it gets past the caps on the absorption phase, when things are bubbling.

[Flux]

I would try dropping the electrolyte to about 3/16 above the plates and see if that helps. If that is the cause then try to find the highest level you can use without mess. As long as plates are covered it is ok but if you are only just covered you have to keep watching the level.

That recommended level sounds high to me.

Flux

[snowcrow]

  The electrolyte rises and falls with the state of charge, low when discharged and high when charged. The best time to water the batteries is near or at a full state of charge. This will prevent the problem of over flow.  If you do water them at a low state of charge, a half an inch above the plates is fine, it will rise as the batteries charge.

Blessings, Snow Crow

[Off grid in Tonopah]

    The liquid that's on the top definitely has an acid component as it does react to soda. The fill is not to 1/8 from the top but 1/8 from the bottom of the fill neck. The little down pipe about an inch long with a slit in the side.

    Tom what bad things would this be a sign of? The rest of the battery function seems as designed.

    I'll try lowering the level but have found that in a months time I'm real close to the plates. I'll just have to start going in the hole every other week. My biggest question is why the profound difference from the 12 volt bank I ran for years and never had wet tops.

    If clearer photos are wanted let me know and I'll put them in my file section. They're just to big to post.

                            Thanks

                            Bob

[Volvo farmer]

Whaaaaa?

You're saying that the acid/water mix somehow increases in volume when the batteries are charged and the volume decreases when the batteries are discharged?

I have never heard of this phenomenon before, do you have some sort of online reference to this? I've been living with batteries for over a year and have never seen what you describe.

[snowcrow]

  Yes, When the acid comes out of solution with the water, bonds with lead to become lead sulfate, the volume changes.  This phenomenon is do to the way the molecules are bonded to the lead.

 Carbon is a good example of this phenomenon. Graphite, coal, and diamonds are all forms of carbon, but the molecules are bonded in different ways, making their specific gravity different. Mass staying the same, but volume changes, making it something different all together.

 Does that may sense?

Blessings, Snow Crow

[TomW]

bob;

The "bad things" were mentioned by the others. Overfilling or overcharging.

I would try just splitting the difference between top of plates and that fill line on the hole sleeve.

Main points to observe are that the plates stay covered and you don't puke out electrolyte when being charged hard. You don't need a lot of electrolyte covering the plates just enough to keep them flooded between inspections. Much more and you risk bubbling it out.

I am no battery expert but have been using a large bank for about 5 or 6 years.

I saw "Sams Club" mentioned. In my mind that often implies junk.

Try playing with the levels awhile but beware of letting the plates get exposed.

Good luck with it .

TomW

[elvin1949]

V.F.

 As the battery charges it heats up.

Fluid's expand as they heat up.

 nuff said

later

Elvin

[zeusmorg]

  Proper fill level on a battery of this type is from the bottom of the tube to about 1/2 the way up that slit you spoke of. If you fill near the top of the slit or to the top of the slit, I guarantee you'll get acid spurting out of the caps when you're charging them.

  Once the liquid reaches the top of the slit, it air pockets the battery and outgassing forces the acid out of the caps.

[richhagen]

I have seen similar results with marine type batteries when too full - I haven't managed to overfill my golf cart type batteries.  When bubbling away near full charge they would push out a bit of fluid if filled too high - the bubbles take up space as well.  I think you need to consider reducing the volume of electrolyte a bit.  You might have to check up on them more often if you are losing enough electrolyte to risk exposing the plates.  Rich

[thirteen]

As a side note; how well is the ventilation in the hole? There maybe a possible biuld up of gas inside without a fan used ever so often. No need to risk everything if there is a problem with the batteries. Thinking of saftey issues. Just an idea.

[chabitus]

I was thinking that maybe the boil over prob is due to the way the batteries are wired together. they are in 4 strings, if one or more string has a lower resistance than it might be absorbing most of the charge energy and could be making it boil over. Normally i can't see it being a prob but if one of the bateries has a prob, the other 3 in the series could be taking too much voltage?

[chabitus]

Opps, i meant to say 3 strings, not 4