Batteries and Battery Acid

[mgm1986]

Hey folks, now that my cart is running again I want to try and keep it that way.

After sitting off the charger for 24+ hour, my pack is sitting at 39v per my DVM. This seems like an overcharge situation.

The PO told me he topped the batteries at some point using battery acid from Napa, NOT distilled water.

Would this cause an overcharge situation? Or is it possibly the charger itself? Or both?

Any input is greatly appreciated!

[ThreeCW]

As per the attached State of Charge Chart, a 36 volt battery pack is at a 100% state of charge at 38.2 volts.

Your 39 volts is not much higher than this ... so not a problem.

My pack of Trojan T-125's are 52.0 to 52.2 volts when fully charged compared to the chart value of 50.93 volts.

I believe that adding acid to top off batteries is not a recommended practice. Perhaps other more knowledgeable can comment why NOT to do this.


Carts Unlimited State of Charge Chart.JPG

[Nsmustang55ol]

That’s 6.5 volts per battery. That seems pretty good but I’m
I expert.

[Sergio]

Adding acid to batteries is a great way to kill them since it will damage the plates.

If You have a good hydrometer and the original acid concentration for your battery (usually around 1.285), do a full charge then measure the electrolyte concentration.

If higher than spec, remove some of the electrolyte and add distilled water to lower the concentration.

The only time you should acid pre-mixed electrolyte is when a battery tips over and looses some of the electrolyte and not because of water evaporation.

[mgm1986]

Thank you, both.

@ThreeCW - I believe you are correct, you are not supposed to add acid to the battery as it changes the ratio of the mixture. My understanding is you should add distilled water to a battery to bring the fluid back to the right level and ratio of water:acid.

But I too am not an expert, thus my question!

Sounds like I might be okay though, at 39v. Just didn't want to ASSUME anything, I learned that lesson years ago!

[mgm1986]

Originally Posted by Sergio

Adding acid to batteries is a great way to kill them since it will damage the plates.

If You have a good hydrometer and the original acid concentration for your battery (usually around 1.285), do a full charge then measure the electrolyte concentration.

If higher than spec, remove some of the electrolyte and add distilled water to lower the concentration.

The only time you should acid pre-mixed electrolyte is when a battery tips over and looses some of the electrolyte and not because of water evaporation.

Thank you, Sergio! That is the info I was looking for. I do have the EZRED SP101 hydrometer and will go through the procedure you suggested. Right now, the hydrometer reads off the charts.

How would I find the correct concentration for my batteries? Duracell 6v.

The hydrometer goes up to 1300.

[worleytech]

I work for a battery manufacturer. We have several storage tanks we fill our new batteries from. All have different acid/DI water ratios. All spec'd out by the engineering group who designed the battery. You should not add a generic acid to your batteries when you do not know what ratio it was designed for. Acid does not evaporate, only the water added to it to get the ratios in spec.
(We sell one 16V battery weighing 1440#)