Lead acid battery fluid change

[stangguy]

I have heard of doing this, but have read somewhere that after washing out the battery with water, that you really need to let it dry fully. The reason being that although you can add water to acid, no problem, but that if you add acid to water, it will kinda "blow"up. Very dangerous. At least that is what I remember reading somewhere.

 

[kschachn]

Oh and by the way, battery chemistry is actually quite complicated. That "sludge" you observe is sloughed off lead sulfate and I think fresh acid will accelerate that undesirable deterioration.

 

[hemitom]

It won`t help a shot battery no, but on half bad battery it might in theory. I have seen sludge from the plates in the acid before, therefore i wonder if it was possible to flush the battery clean and then add fresh acid to it to prolong the battery life.

Fair enough when the battery acid needs to be disposed off in proper maner...

exactly ! some would just dump the acid where ever they could.
For me its not worth the personal risk in dumping and transporting acid to a hazardous waste site to get maybe another year out of a battery (but thats just me )

 

[kschachn]

I wonder what the disposal requirements are there in Norway?

 

[kebabaluba]

I have heard of doing this, but have read somewhere that after washing out the battery with water, that you really need to let it dry fully. The reason being that although you can add water to acid, no problem, but that if you add acid to water, it will kinda "blow"up. Very dangerous. At least that is what I remember reading somewhere.

You think of oxyhydrogen gas, and yes if ignited its a bad thing. Therefore charging batteries is a hazard.

 

[wrcsixeight]

The plates degrade and shed material which falls to the bottoms of the cells.

When the sheddings touch the bottoms of the plates, they can short out that cell.

True deep cycle batteries with thicker plates have more to shed, and have more space under the plates for accumulation.

Source:
https://marinehowto.com/what-is-a-deep-cycle-battery/

Draining the electrolyte, can take some of this shedding/sludge with it. the pic above does not make it look easy to get ALL the sheddings out.

Less sludge in the bottom, the longer the battery can go before the sheddings build up enough to short out a cell(s)

I suspect most batteries die from hardened sulfation due to chronic undercharging, rather than from a shorted cell due to build up of plate sheddings.

I'd spend the time and effort of exchanging the electrolyte regularly, with time spent on a charger insuring a true full charge is regularly achieved as the vehicles charging system will not do this in 99.5% of vehicles in their usual usage.

This is the single best way to extend battery longevity, and the green light on a smart charger does not mean true full charge has been achieved, only that the charger has decided to end charging at higher voltages and has dropped to maintenance/float voltage.

A temperature compensating hydrometer will reveal this fact, but any charging towards true full state of charge is better than leaving it where it was, and is beneficial. True full charge is Ideal, and takes a lot longer than most will ever believe, until they actually use a hydrometer.
OTC 4619, and make sure no bubbles stick to the float.

Achieving maximum specific gravity of the electrolyte on older batteries usually requires an adjustable voltage power supply as the smart charger will just keep dropping to float/maintenance voltage way too soon.

 

[kebabaluba]

I wonder what the disposal requirements are there in Norway?

Quite strict, we sort the garbage too such as glass bottles, cardboard, plastic etc. So no i had no intention dumping acid in the drain.

 

[kebabaluba]

Oh and by the way, battery chemistry is actually quite complicated. That "sludge" you observe is sloughed off lead sulfate and I think fresh acid will accelerate that undesirable deterioration.

Is that a proven fact?

 

[ragtoplvr]

I used to work for a battery manufacturer. The "Sudge" is active material that falls off the plates. When builds up and reaches the bottom of the plates the cell will short. Disturbing it may cause plates to short sooner. If a battery boils out the electrolite, you can gain life by restoring the correct specific gravity. The overcharge also causes more active material to fall off the plates so you have a lower capacity battery. VERY cold climates can benefit from a higher specific gravity such as 1300. It will also shorten battery life and it IS a proven fact. That is the only thing that might be of benefit for Norway.

Rod

 

[kschachn]

When insoluble lead sulfate is precipitated out of the plates it falls to the bottom as has been described. This also raises the pH of the electrolyte, which slows the reaction. Adding fresh sulfuric acid to the battery will accelerate the process.

Again as has been mentioned the best way to preserve a battery is proper charging.

 

[kebabaluba]

The plates degrade and shed material which falls to the bottoms of the cells.

When the sheddings touch the bottoms of the plates, they can short out that cell.

True deep cycle batteries with thicker plates have more to shed, and have more space under the plates for accumulation.

Source:
https://marinehowto.com/what-is-a-deep-cycle-battery/

Draining the electrolyte, can take some of this shedding/sludge with it. the pic above does not make it look easy to get ALL the sheddings out.

Less sludge in the bottom, the longer the battery can go before the sheddings build up enough to short out a cell(s)

I suspect most batteries die from hardened sulfation due to chronic undercharging, rather than from a shorted cell due to build up of plate sheddings.

I'd spend the time and effort of exchanging the electrolyte regularly, with time spent on a charger insuring a true full charge is regularly achieved as the vehicles charging system will not do this in 99.5% of vehicles in their usual usage.

This is the single best way to extend battery longevity, and the green light on a smart charger does not mean true full charge has been achieved, only that the charger has decided to end charging at higher voltages and has dropped to maintenance/float voltage.

A temperature compensating hydrometer will reveal this fact, but any charging towards true full state of charge is better than leaving it where it was, and is beneficial. True full charge is Ideal, and takes a lot longer than most will ever believe, until they actually use a hydrometer.
OTC 4619, and make sure no bubbles stick to the float.

Achieving maximum specific gravity of the electrolyte on older batteries usually requires an adjustable voltage power supply as the smart charger will just keep dropping to float/maintenance voltage way too soon.

I knew there was some truth to my theory when i read your answer.

 

[kebabaluba]

I used to work for a battery manufacturer. The "Sudge" is active material that falls off the plates. When builds up and reaches the bottom of the plates the cell will short. Disturbing it may cause plates to short sooner. If a battery boils out the electrolite, you can gain life by restoring the correct specific gravity. The overcharge also causes more active material to fall off the plates so you have a lower capacity battery. VERY cold climates can benefit from a higher specific gravity such as 1300. It will also shorten battery life and it IS a proven fact. That is the only thing that might be of benefit for Norway.

Rod

Where i live is almost same climate as UK, not a severe cold here. But good to know.

 

[wpod]

maybe y

Why screw around dumping, flushing acid,
Which by the way is highly corrosive, needless to say dangerous on a battery worth $100 to 200

Danger is good.

 

[JHZR2]

You wont get the shed lead all out, and to do so will be a major hazmat mess for someone not setup to do this. And the benefits will be marginal; the lead that was shed from the plates is a problem.

 

[FordMan59]

I've personally never tried it but I've seen videos of people doing it on You Tube. An old friend of mine that I worked with years ago told me he dumped the acid, cleaned the battery and put new acid in his motorcycle battery one time when it wouldn't take a charge, it then took a charge but, I don't know how long it lasted afterward. I can see it maybe being worth it on a motorcycle battery/lawn equipment battery if it went bad near the end of the riding/mowing season then buying new the next spring if needed. Every motorcycle battery I ever bought for my bikes came dry. The purchaser had to put the acid in the battery and charge it after it was bought. I would think the biggest concerns would be safety, not splashing it on your clothes/skin/eyes and getting rid of the waste acid.

A couple years ago I got tired of having to go buy a new battery every spring for my mom's riding mower so I cut the ring terminals off the cables, got some regular battery terminals for a car and put a car battery in the mower. I was paying $20-30 a year for a lawn and garden battery with a 6 month warranty, I went to Rural King and got a battery with a 1 year free replacement 5 year pro rated warranty for $55. That sucker spins that little 15.5 HP motor now.

 

[Davejam]

Sulfuric acid is cheap. Super cheap compared to lead.
This would be a good idea if not for all the other concerns and modes of failure already mentioned here.

 

[ragtoplvr]

One of the best things you can do besides proper charging is fasten the battery down so it does not vibrate. My last rider, battery lasted a year, make good hold down, sit it on rubber mat, batteries started lasting many years.

Rod

 

[FordMan59]

One of the best things you can do besides proper charging is fasten the battery down so it does not vibrate. My last rider, battery lasted a year, make good hold down, sit it on rubber mat, batteries started lasting many years.

Rod

Those mower batteries were tied down and on a rubber mat.

 

[barryh]

I see some vendors sell battery acid for lead acid batteries, and that got me thinking and gave me a bit nuts idea. We change fluids on our cars on regular basis, what if we did the same on the battery too to prolong battery life? I mean the acid solution do deteriorate as well as other fluid on the car and it absorbs sludge from cells, i have seen sludge inside the cells inside older batteries. This gives me an idea. What if we pull away older battery from the car, pull the caps and drain it, rinse the cells clean with pure water, add new battery acid, recharge and then install back on the car. I mean, it could work in theory. Any one tried that before?

I did exactly that to an old 6 volt motorcycle battery many years ago. I flushed it with distilled water and quite a lot of dirty sludge came out. It was one of those batteries with a clear see thru case and looked visibly cleaner afterwards It's hard to know if it did any good but the battery carried on for years afterwards. I didn't charge it afterwards. I reasoned that if I was adding acid of the correct full specific gravity then I should ensure the battery was fully charged before flushing and adding the new acid.

 

[92saturnsl2]

Sulfuric acid is easy to neutralize. Calcium carbonate (lime) works well as it does not give off much heat. CaCO3+H2SO4 --> CaSO4 [calcium sulfate aka gypsum]+H2O+CO2. Or use baking soda, sodium carbonate (washing soda) or countless others.

Not sure how the lead that might be present in the solution might react-- sounds like a fun science experiment though!