Battery question: distilled water or premix electrolyte when adding ?

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mtnmankev

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I recently got a couple big 8D deep cycle batteries for my solar setup, and now they appear to have lost a little electrolyte even though with my setup it's impossible to boil them.
I'm thinking for general principle I might want to add some liquid and bring the level up, even if I don't go clear to the top of the battery.
Currently the level is well above the plates, and touches the split ring inside about a quarter inch up from the bottom of the split.

A neighbor told me about a pamphlet from a major auto manufacturer (around the 1970's) which went into great detail about servicing batteries, and when to add distilled water, or use premix electrolyte.
It makes sense that depending on the hydrometer readings I get when the batteries are at theoretical full charge, I might want to add the premixed stuff instead of diluting the present solution with water to help prolong battery life.

Any thoughts or ideas on the topic, and are there any old farts like myself who might have been around when the car makers provided real service info and saw that pamphlet or had a course that taught it?
 

Turbo4whl

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Currently the level is well above the plates, and touches the split ring inside about a quarter inch up from the bottom of the split.
This description tells me, the batteries now have the correct amount of electrolyte. Why add more?
 

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Something tells me the level should be a tad higher since the split tubes are so long inside the case.
And that would also help insure the level can't get so low the plates are exposed.
 

mtnmankev

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The theory my neighbor and I were discussing was if the specific gravity is within the green zone but closer to the top it might be okay to simply add distilled water.
Conversely, if the reading was at the lower end of the green zone, the premix solution might be preferred.
Looking into the battery, it looks beautiful inside, no blackening, no signs of sulfation, and the electrolyte is crystal clear.
The batteries are only a few months old, so that's a good sign I hope to continue.
 

fast 99

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Up to the split rings. Really only need to keep the plates submerged. Do not add electrolyte. Just distilled water.
 

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Even if there is somehow a loss of fluid, as long as it's not below the plates, it's probably fine. Even if it did get a little lower than you remember over some time, if there is no visible spillage or venting from boiling I would assume evaporation. At that point all the salts (electrolytes) have stayed behind and the water evaporated off (heavy stuff like salt can't easily rise up into the atmosphere or even just away from the battery unless carried by steam like if it boiled), so at that point it should need more pure (distilled) water and nothing else to get it back to the level it was. Anything else will make it too mineral rich and could actually be worse than if you just left it alone.
 

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The batteries are only a few months old, so that's a good sign I hope to continue.
This new in their life just distilled water
 

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The only thing that evaporates enough to matter in a normal amount of time is the water, so you want to add distilled to bring the level and concentration to where it should be. if the battery tips, gets overcharged, is on the older side, has contamination (hard water, dirt, etc) then I would personally dump out the acid, rinse with distilled water , dump that out, then fill with electrolyte you can buy at napa or other places.
The little specific gravity gauge can help if you were starting at a point where you need to determine if you need to adjust levels (Since dumping an otherwise fine electrolyte is a decent amount of acid, no need to waste)
If you were using an older battery or you needed to clean up some sulfation I would put the big 30+amper on for a while and get it warm, undo some of the corrosion, then discard that electrolyte and put new in. But that may not be adviseable depending on the use for the battery. Like, I would not do that to a lawn mower battery if its been used on my lawn, heat it up just might cause plates to touch if the internal stuff is worn from vibrations, corrosion, age. etc..

But as always dont play with acid unless you have baking soda on hand to neutralize any accidental spills or get it on you etc.
 

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Keep in mind that as a battery charges the plates warm up. As they warm up the water will expand. I would leave it alone. Check it occasionally and if it gets below the splits then add DW.
 

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I'm not sure how or where adding electrolyte to existing wet cell auto or deep cycle type batteries even entered the conversation...
Does anyone do this, and why?
You can't even really buy the stuff excpet for the little pre-made volumetric containers for some of the little mower and powersport batteries that ship dry.

Let's not try to reinvent a perfectly round wheel here with...idk what.
 
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mtnmankev

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I'm not sure how or where adding electrolyte to existing wet cell auto or deep cycle type batteries even entered the conversation...
Does anyone do this, and why?
You can't even really buy the stuff excpet for the little pre-made volumetric containers for some of the little mower and powersport batteries that ship dry.

Let's not try to reinvent a perfectly round wheel here with...idk what.
I started it when I began the thread.
I am sick and tired of buying new batteries for my solar setup to power the house and I want to try and extend the charge, power output, and service life of the batteries I recently bought.
 

AuroraGirl

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I started it when I began the thread.
I am sick and tired of buying new batteries for my solar setup to power the house and I want to try and extend the charge, power output, and service life of the batteries I recently bought.
Napa does sell large box of acid that’s at the pre set percentage
 

Grit dog

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I started it when I began the thread.
I am sick and tired of buying new batteries for my solar setup to power the house and I want to try and extend the charge, power output, and service life of the batteries I recently bought.

I presume you feel like the life span of your batteries is considerably shorter than it should be.
Don’t have a clue how your system is set up or performs, but do you ever run them down to a lower than optimal SOC?
And where you’re at is not “extreme” heat but it’s still the desert SW, similar weather to Albq I’d imagine. Is your battery bank in a conditioned building? Heat and AC? But more so AC during the hot months.
High ambient temps also shortens battery life significantly.
 

fast 99

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I'm not sure how or where adding electrolyte to existing wet cell auto or deep cycle type batteries even entered the conversation...
Does anyone do this, and why?
You can't even really buy the stuff excpet for the little pre-made volumetric containers for some of the little mower and powersport batteries that ship dry.

Let's not try to reinvent a perfectly round wheel here with...idk what.
This subject goes back to when batteries were shipped dry. I worked at gas stations. All batteries were filled at time of sale. Adding additional acid after initial fill was never recommended. And to be honest nowhere I worked at had distilled water available for topping off. Batteries back then lasted about the same as today 4-5 years. Only difference is the need to watch electrolyte more closely.
 

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