Adding distilled water to maintenance free battery

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wife's Toyota V6 has the "maintenance free" battery but the eye glass is showing red which says "add distilled water" So I tore off the maintenance free sticker and unscrewed the cell caps and added about a 20oz distilled water. Now it is on the charger at 10 amps for 15 minutes then 2 amps until the charge gauge is at or near zero. The cells are bubbling nicely now and there were no dry cells.

Did I just ruin this battery or is the "maintenance free" thing a bunch of bunk? It is a 2008 battery.
 
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IMHO...bunk. Lead acid batteries require distilled water (or electrolyte if the level goes too low) to maintain levels. Years ago, I had a DieHard that was supposed to be maintenance free (and supposedly sealed). One merely had to grab the case about halfway down and pry out and the entire top half of the battery came off (it was the lid). One could then add water to the battery to keep it from going dry.

I learned this after the same battery when dry in my Dad's car and he had to replace it. One of the Sears techs allowed me to see the new battery being filled and I realized the "score". To me, this was just another way to sell more batteries as they are inevitably going to go dry at some point (sooner than later in the heat of Texas).
 
It has been my experience that when the electrolyte level falls below the top of the plates, the battery dies a quick death after refilling and recharging.

They say that only the part of the plates that was exposed is ruined, with the corresponding amount of capacity lost,but as said above, every time I have caught low electrolyte levels and refilled them. I was buying a new battery within a month.

Hope your experience proves differently.
 
Nah, you're fine. I top up my maintenance free batteries occasionally, no problem. Thanks for the tip on the Sears battery, I'll keep that in mind.
 
A modern car battery that uses the later Calcium doped plates will usually not need water during a normal life of 5? years or so. First the manufacture must have put in the correct amount of electrolyte and the charging system must not overcharge the battery. In addition; the car owner is not expected to deep cycle the battery many times which would require the alternator to apply a heavy recharging voltage/current. I've never needed to add water to a mainence free battery in the 5-7 years I've owned one and I do check the level.
 
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Hi Doog, the only thing you did wrong was not to check the water before but it is not your fault, they are not really maintenance free, the do evaporate less water because of their chemistry and the better ones have catalytic converters in the caps to reconvert the hydrogen and oxygen back to water but they are not 100% efficient so over time they do dry out like a conventional battery, it is more common in hot climates and/or tight engine compartments. The point regarding plates calcifying beyond reconversion to acid when exposed to air is valid but depending on your charger you might be able to save it, perhaps yours have a desulpation mode or does it constantly, also if you have a setting for AGM or VRLA (sealed) battery use it, the terminal voltage is higher and it will help desulphation, actually that "is" the right terminal voltage for a calcium/calcium (maintenance free)battery. Was the car originally fitted with a maintenance free battery or with a low maintenance one? they have different terminal voltages. How long is the warranty on the battery? they usually last a bit longer than that and it's over. Perhaps the temperature sensor for the battery is bad and the computer is overcharging it, that will easily do it. I hope this helps.
 
Originally Posted By: Eddie
A modern car battery that uses the later Calcium doped plates will usually not need water during a normal life of 5? years or so. First the manufacture must have put in the correct amount of electrolyte and the charging system must not overcharge the battery. In addition; the car owner is not expected to deep cycle the battery many times which would require the alternator to apply a heavy recharging voltage/current. I've never needed to add water to a mainence free battery in the 5-7 years I've owned one and I do check the level.


While I generally agree, not sure what you mean by heavy recharge voltage.

Current I agree with, and so long as a controlled current source is applied to keep the rate below about C/5, all is well.

Alternators don't historically have that control, and the bigger ones can drive 40-50A+ into the battery, way too fast of a charge, and hard on the alternator too.

But voltage isn't a problem so long as it isn't above ~15.5V. In fact, a high voltage equalization charge can be a good thing, though at very low current.
 
Originally Posted By: Doog
wife's Toyota V6 has the "maintenance free" battery but the eye glass is showing red which says "add distilled water" So I tore off the maintenance free sticker and unscrewed the cell caps and added about a 20oz distilled water. Now it is on the charger at 10 amps for 15 minutes then 2 amps until the charge gauge is at or near zero. The cells are bubbling nicely now and there were no dry cells.

Did I just ruin this battery or is the "maintenance free" thing a bunch of bunk? It is a 2008 battery.


Congrats you just extended the life of your battery and did not have to open your wallet.
 
in my experience, this will extend the life but are now on borrowed time. I've done this a few times and in some cases it'd last for a while longer and in others just take a dive.

If it were my car, I'd pat myself on the back and put $100 in a drawer (or glovebox) for when it dies. If it was the wife's, I'd be comparing AA and AZ online and counter prices and buying new (btw-- just bought a new batt yesterday-- AA has a 15% internet sale, and AZ's premium battery is now AGM... both made by JCI).

The other kicker is that the maintenance free tend to need to hold some pressure to prevent excessive boil-off. I think it was 2 psi for typical VRLA last time I looked.

M
 
Originally Posted By: Doog
wife's Toyota V6 has the "maintenance free" battery but the eye glass is showing red which says "add distilled water" So I tore off the maintenance free sticker and unscrewed the cell caps and added about a 20oz distilled water. Now it is on the charger at 10 amps for 15 minutes then 2 amps until the charge gauge is at or near zero. The cells are bubbling nicely now and there were no dry cells.

Did I just ruin this battery or is the "maintenance free" thing a bunch of bunk? It is a 2008 battery.

Adding the distilled water is fine. Typically you would add it after its charged though as the levels typically rise after/during recharge.
Contrary to what many "tinkerers" like to spout, avoid unnecessary recharging/equalizing. Only charge/boost enough to get your car running. I don't recommend anything more on a typical consumer battery charger, especially a ferroresonant one, they typically do not have the voltage regulation that an alternator does. High voltage is a quick death for automotive SLI batteries. They are float type batteries by definition and their construction doesn't lend well to over charging especially high voltage, anything over about 14.2 volts or 2.37 volts per cell is to high.

Edit: The reason they have a minimal tolerance for over charging is because unlike deep cycle batteries they have very thin plates and grids which are very sensitive to corrosion(caused by high voltage)as well as a much finer past/lead oxide. Not to mention the positive plate wrapping, essential to keep active material on the grid/plate, isn't thick enough for high voltage recharging like you would see with a deep cycle battery.
 
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Originally Posted By: 3311
Originally Posted By: Doog
wife's Toyota V6 has the "maintenance free" battery but the eye glass is showing red which says "add distilled water" So I tore off the maintenance free sticker and unscrewed the cell caps and added about a 20oz distilled water. Now it is on the charger at 10 amps for 15 minutes then 2 amps until the charge gauge is at or near zero. The cells are bubbling nicely now and there were no dry cells.

Did I just ruin this battery or is the "maintenance free" thing a bunch of bunk? It is a 2008 battery.

Adding the distilled water is fine. Typically you would add it after its charged though as the levels typically rise after/during recharge.
Contrary to what many "tinkerers" like to spout, avoid unnecessary recharging/equalizing. Only charge/boost enough to get your car running. I don't recommend anything more on a typical consumer battery charger, especially a ferroresonant one, they typically do not have the voltage regulation that an alternator does. High voltage is a quick death for automotive SLI batteries. They are float type batteries by definition and their construction doesn't lend well to over charging especially high voltage, anything over about 14.2 volts or 2.37 volts per cell is to high.

Edit: The reason they have a minimal tolerance for over charging is because unlike deep cycle batteries they have very thin plates and grids which are very sensitive to corrosion(caused by high voltage)as well as a much finer past/lead oxide. Not to mention the positive plate wrapping, essential to keep active material on the grid/plate, isn't thick enough for high voltage recharging like you would see with a deep cycle battery.


Id agree that unnecessary recharging may not provide any value.

However, I have two issues with your commentary:

First, most modern alternators will put well over 14.2V out, which means that the battery is seeing that on "float" duty attached to the electrical system.

Second, the alternator typically is not current limited, and so if a battery is at a low SOC, the alternator may source more current than desirable for a recharge, which should generally be between C/20 and C/5 max. Modern chargers are power electronics based and have pretty fine control of this (as long as the user sets it right). Good ones even have three or four mode charging scenarios to include all the right phases to get an optimal charge, something that an alternator just wont do.

Curious as to why you think that an equalization charge on a battery that is NOT designed for deep cycling, but has been either due to self discharge or misuse, would be an issue. There are a ton of things that seem to offer benefit in terms of sulfidation, balancing, etc. Different manufacturers offer them in different ways. Charging at 8 or 10A on an 85Ah battery and doing these things isnt going to pummel it with a ton of current and damage, and the time at voltage, which is really key, is so relatively short that I cannot imagine that the kinetic effects of corrosion and whatnot are viable, especially at cooler temperatures. In AGM batteries, which are getting more popular, recombination is so much better/faster, that dry-out is not an issue, because offgassing to the ambient is about 1% of a normal flooded battery.

Would love to get more of your thoughts on this, since apparently I am a "tinkerer" who is wrong (yet has batteries in service that are >10 years old).
 
Originally Posted By: meep

The other kicker is that the maintenance free tend to need to hold some pressure to prevent excessive boil-off. I think it was 2 psi for typical VRLA last time I looked.
M


Maintenance free flooded batteries (you can hear liquid sloshing around when you move them), which is what most maintenance free car batteries actually are, do not hold any pressure whatsoever. They are vented and will leak electrolyte if tipped far enough.
 
Originally Posted By: JHZR2
Originally Posted By: 3311
Originally Posted By: Doog
wife's Toyota V6 has the "maintenance free" battery but the eye glass is showing red which says "add distilled water" So I tore off the maintenance free sticker and unscrewed the cell caps and added about a 20oz distilled water. Now it is on the charger at 10 amps for 15 minutes then 2 amps until the charge gauge is at or near zero. The cells are bubbling nicely now and there were no dry cells.

Did I just ruin this battery or is the "maintenance free" thing a bunch of bunk? It is a 2008 battery.

Adding the distilled water is fine. Typically you would add it after its charged though as the levels typically rise after/during recharge.
Contrary to what many "tinkerers" like to spout, avoid unnecessary recharging/equalizing. Only charge/boost enough to get your car running. I don't recommend anything more on a typical consumer battery charger, especially a ferroresonant one, they typically do not have the voltage regulation that an alternator does. High voltage is a quick death for automotive SLI batteries. They are float type batteries by definition and their construction doesn't lend well to over charging especially high voltage, anything over about 14.2 volts or 2.37 volts per cell is to high.

Edit: The reason they have a minimal tolerance for over charging is because unlike deep cycle batteries they have very thin plates and grids which are very sensitive to corrosion(caused by high voltage)as well as a much finer past/lead oxide. Not to mention the positive plate wrapping, essential to keep active material on the grid/plate, isn't thick enough for high voltage recharging like you would see with a deep cycle battery.


Id agree that unnecessary recharging may not provide any value.

However, I have two issues with your commentary:

First, most modern alternators will put well over 14.2V out, which means that the battery is seeing that on "float" duty attached to the electrical system.

Second, the alternator typically is not current limited, and so if a battery is at a low SOC, the alternator may source more current than desirable for a recharge, which should generally be between C/20 and C/5 max. Modern chargers are power electronics based and have pretty fine control of this (as long as the user sets it right). Good ones even have three or four mode charging scenarios to include all the right phases to get an optimal charge, something that an alternator just wont do.

Curious as to why you think that an equalization charge on a battery that is NOT designed for deep cycling, but has been either due to self discharge or misuse, would be an issue. There are a ton of things that seem to offer benefit in terms of sulfidation, balancing, etc. Different manufacturers offer them in different ways. Charging at 8 or 10A on an 85Ah battery and doing these things isnt going to pummel it with a ton of current and damage, and the time at voltage, which is really key, is so relatively short that I cannot imagine that the kinetic effects of corrosion and whatnot are viable, especially at cooler temperatures. In AGM batteries, which are getting more popular, recombination is so much better/faster, that dry-out is not an issue, because offgassing to the ambient is about 1% of a normal flooded battery.

Would love to get more of your thoughts on this, since apparently I am a "tinkerer" who is wrong (yet has batteries in service that are >10 years old).

Let me see if I can address your questions one by one:

-Modern alternators will not put high voltage for vary long if at all. Certainly not long enough to damage the battery.

-High initial current from an alternator is not detrimental. It will only be high(with respect to battery recharging) for a relatively short period of time.

-Equalization is not typically necessary for a battery in float service. What do you think an properly functioning alternator is doing after the high current initial recharge? The battery is effectively being equalized by the float charge its receiving from the alternator. Abnormal sulfation and cell voltage imbalances will occur from repeated under charging, not something an automotive battery experiences if used with any regularity.

-Overcharging is extremely detrimental, even at cooler temperatures, Read the last part of my post you quoted with regard to SLI battery construction. When these batteries are excessively gassing(over 2.37 vpc), even for a short period of time, even on a relatively cool battery you are corroding(abnormally) the positive grid and shedding(abnormally)active material. Look inside the battery after you recharge it. That black/dark red/grey slushy, goopy stuff you are seeing on top of the strap and plates is lost active material. This something we need to cognizant of even on the very large industrial batteries which are infinitely more robust in design and construction.

-AGM/Gel batteries. They are a technology borrowed from temperature controlled Stationary/UPS applications designed to reduce significant maintenance costs/man hours in maintaining these strings of cells. IMO a complete misapplication for automotive use and ridiculously over priced. AGM(Activated Glass Mat)and Gel are "starved electrolyte" technologies, they basically have less electrolyte than a comparable flooded battery. Hence they cannot achieve the same capacity as a flooded electrolyte battery of the same given cube or plate size. Not sure where you heard the "recombination is better/faster", the process is the same, they may recharge faster due to the lower capacity this could be where the manufacturers are getting their efficiency claims. And of course they don't "dry out", they are SVRLA(sealed valve regulated, they only "burp" a few times in their typical life cycle.

I guess I should give the battery manufacturers credit for getting people to buy something that costs less to build, will last half as long, provide half as much power and sell it at twice the price. And before anyone claim about their warranties, there is so much initial profit they afford the long warranties. I promise you none of the manufactures are using these batteries extensively in their vehicle fleets.
 
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Originally Posted By: brianl703
Originally Posted By: meep

The other kicker is that the maintenance free tend to need to hold some pressure to prevent excessive boil-off. I think it was 2 psi for typical VRLA last time I looked.
M


Maintenance free flooded batteries (you can hear liquid sloshing around when you move them), which is what most maintenance free car batteries actually are, do not hold any pressure whatsoever. They are vented and will leak electrolyte if tipped far enough.
I beleve what he meant was they are not pressurized but the build pressure during recharge(heat and gassing). Their spring loaded vent caps (VRLA - Valve Regulated Lead Acid) vent at about 2-3psi. Anything more pressure and it will pop the polypropylene case.
 
On the way home there was a typical road hazard. At home 1 of two new Maintenance Free batteries had fallen over leaking electrolyte. Group 31 maintenance free. These have never been in service - brand new. So, I have battery acid issue. Do I replace the acid? If I add water, I just dilute it from the beginning - not good.
 
Originally Posted by 3311
Originally Posted by brianl703
Originally Posted by meep

The other kicker is that the maintenance free tend to need to hold some pressure to prevent excessive boil-off. I think it was 2 psi for typical VRLA last time I looked.
M


Maintenance free flooded batteries (you can hear liquid sloshing around when you move them), which is what most maintenance free car batteries actually are, do not hold any pressure whatsoever. They are vented and will leak electrolyte if tipped far enough.
I beleve what he meant was they are not pressurized but the build pressure during recharge(heat and gassing). Their spring loaded vent caps (VRLA - Valve Regulated Lead Acid) vent at about 2-3psi. Anything more pressure and it will pop the polypropylene case.


Thanks - yeah that's what I was getting at.
 
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