90 wt Gear Oil for Batteries ?

[Cane Pole]

That Thomas Edison was a sharp dude. He came up with the first nicad battery, but most folks don't know this either.

I believe the oil helped stop electrolyte evaporation. You usta could buy Edison battery oil but I ain't seen any in a long time. It looked kinda like castor oil.

[Cane Pole]

I bet CatFan knows all about this stuff.

[Atchafalaya_man]

For those of you that don’t want to try this oil trick (such as me), the best thing you can do for your battery’s life is to IMMEDIATELY recharge it to its ideal voltage of 13.6 volts, and KEEP IT at that voltage using a smart charger designed for that purpose. Such devices or chargers that do this are sometimes called battery maintainers.

You are “floating the battery”. Floating meaning to have a charger/maintainer connected 24/7 that doesn’t put more, nor allow the battery to naturally discharge to less than the ideal 13.6 volts while it is idle between uses.

What kills most batteries is when plates become internally connected or ‘shorted’ by crystals (sulfates) that grow on the surface of the plates. A fully charged lead-acid battery is filled with pure sulfuric acid. Crystals don’t grow in pure sulfuric acid.

However, discharging chemically changes some of the sulfuric acid to water. Crystals grow when the battery is in the water-state (discharged) so you want to eliminate the water-state as quickly as possible after discharge.

[jimp]

does charging a batt after you add water to it convert this newly added water over to acid ?

[Crestliner08]

For those of you that don’t want to try this oil trick (such as me), the best thing you can do for your battery’s life is to IMMEDIATELY recharge it to its ideal voltage of 13.6 volts, and KEEP IT at that voltage using a smart charger designed for that purpose. Such devices or chargers that do this are sometimes called battery maintainers.

You are “floating the battery”. Floating meaning to have a charger/maintainer connected 24/7 that doesn’t put more, nor allow the battery to naturally discharge to less than the ideal 13.6 volts while it is idle between uses.

What kills most batteries is when plates become internally connected or ‘shorted’ by crystals (sulfates) that grow on the surface of the plates. A fully charged lead-acid battery is filled with pure sulfuric acid. Crystals don’t grow in pure sulfuric acid.

However, discharging chemically changes some of the sulfuric acid to water. Crystals grow when the battery is in the water-state (discharged) so you want to eliminate the water-state as quickly as possible after discharge.

O.K., then why does your car battery, which is constantly being charged, still only last about as long as your boat batteries do?

[CrappiePappy]

does charging a batt after you add water to it convert this newly added water over to acid ?

According to everything I've read ... you should add distilled water to a battery that's low on water .. AFTER it's charged up. Thumbs Up

"Batteries should be watered after charging unless the plates are exposed, then add just enough water to cover the plates. After a full charge, the water level should be even in all cells and usually 1/4" to 1/2" below the bottom of the fill well in the cell (depends on battery size and type)."
(copied from Deep Cycle Battery FAQ )

That being said ... the answer to your question is "no". The water does not change to acid.

(information source - Wikipedia) .... "Lead-acid batteries are made up of plates of lead and separate plates of lead dioxide, which are submerged into an electrolyte solution of about 35% sulfuric acid and 65% water.^[2] This causes a chemical reaction that releases electrons, allowing them to flow through conductors to produce electricity. As the battery discharges, the acid of the electrolyte reacts with the materials of the plates, changing their surface to lead sulfate. When the battery is recharged, the chemical reaction is reversed: the lead sulfate reforms into lead oxide and lead. With the plates restored to their original condition, the process may now be repeated."

... cp

[cache22]

Battery acid is around 35% sulfuric acid. It weakens as battery discharges as some of the acid reacts to form water. That is why you can use a hydrometer to determine state of charge for a battery. Charging a battery reverses the discharging reaction. "Pure" 100% sulfuric acid does not exist.... would be extremely hazardous if it did.

[CrappiePappy]

O.K., then why does your car battery, which is constantly being charged, still only last about as long as your boat batteries do?

I think it has to do with the size & thickness difference of the lead plates in a car battery vs a marine battery.

"Both car batteries and deep cycle batteries are lead-acid batteries that use exactly the same chemistry for their operation (see How Batteries Work for more information). The difference is in the way that the batteries optimize their design:

• A car's battery is designed to provide a very large amount of current for a short period of time. This surge of current is needed to turn the engine over during starting. Once the engine starts, the alternator provides all the power that the car needs, so a car battery may go through its entire life without ever being drained more than 20 percent of its total capacity. Used in this way, a car battery can last a number of years. To achieve a large amount of current, a car battery uses thin plates in order to increase its surface area.
• A deep cycle battery is designed to provide a steady amount of current over a long period of time. A deep cycle battery can provide a surge when needed, but nothing like the surge a car battery can. A deep cycle battery is also designed to be deeply discharged over and over again (something that would ruin a car battery very quickly). To accomplish this, a deep cycle battery uses thicker plates."

(source of information - How Stuff Works - HowStuffWorks "What's the difference between a normal car battery and a deep-cycle battery?" )

... cp

[jimp]

I've always added/filled the battery cells with distilled water BEFORE I charge it up, been doing it this way for years. Don't know that it would make a difference but I can't really complain about my battery life. Seems like all the one'sin the cars just "die", no warning, no nothing, just won't start one day from internal shorts. The cranking batt on the boat did that one time as well.

[Panfish16]

Thanks guys for the good info and useful links! I learned alot from this post and the posted links, good stuff!