Water overflows from batteries

[DIRTPIT HC]

Joneq, can you give the guys the highest volts reached when charging? Also, resting voltage of full pack 12 hrs after charging. Lets us know your charging habits. Do you charge when its not moving, overnight, once a week? Sounds like from your first post that this has been happening for a while. Years?

[BobBoyce]

My RXV had the same batteries. I removed the dealer installed water refill system and installed the new individual battery caps that were on the new L16H batteries I bought for my solar power system last year. I had removed those caps and installed a set of platinum catalyst based water miser caps.

Bob

[jonequest]

Originally Posted by Golf cart guy

Don't bother. Bite the bullet, get yourself some batteries

Sure, I have an extra $600-$800 laying around. My cart still runs fine (just not quite as fast as 4 years ago) and all my batteries tested at 8.35v-8.4v last night. I just want to keep them going as long as possible.

[JohnnieB]

Originally Posted by jonequest

I have had a problem since I first got my cart. The water in my batteries always seems to bubble out through the caps and ends up dripping down the side of the batteries and rotting out the battery tray. I am on my second new battery tray in about 4 years and this one is starting to corrode badly as well and it is only 6 months old. I fill the batteries to a little below touching the plastic that goes down into the cells so I don't think I am overfilling them am I? I am not sure what to do about this. I worry if I keep the water lower it will be dangerous for my batteries since the bubbling will still cause seepage too. Any suggestions?

I have a 2004 EZGO with 48 volts and I use an LVS brand charger.

You are overfilling your batteries.
US Battery states that the electrolyte level should be kept at 1/4" below the bottom of the fill well after being fully charged. (US Battery care and maintenance brochure attached)

When a lead-acid battery is charged, the electrolyte physically grows in volume, so if filled to the bottom of the fill wells when the battery is partially discharged (which is already an over filled condition), the battery will be overflowing when charged.

[JohnnieB]

Originally Posted by jonequest

Sure, I have an extra $600-$800 laying around. My cart still runs fine (just not quite as fast as 4 years ago) and all my batteries tested at 8.35v-8.4v last night. I just want to keep them going as long as possible.

If the voltage was measured about 12 hours after the charger shut off, than they are only being charged to about 85% SoC. (Voltage vs SoC chart from US Battery attached)

That may be due to acid loss, but it also may be partially due to the charger being used.

US Battery batteries have a different charge profile than Trojan batteries and require a higher finish voltage from the charger. Contact USB and check if your LSV charger (LSV4800 ??) is an acceptable charger for their products.

Originally Posted by jonequest

I have an aluminum tray now but it is starting corrode too. I actually regret getting an aluminum tray since I can't weld it as easily when it rots out in spots.

I have the gang cap style with a handle that turns 4 at a time to open them. They definitely don't seem to be very watertight at all. I also noticed that my cart is not as fast as it used to be. The batteries are about 4 years old now if I remember right. Since electrolyte has slowly seeped out and been replaced by distilled water should I check the acid PH of the batteries? The distilled water gets turned into acid as the battery gets charged right?

You need to check the SG (Specific Gravity) of the electrolyte rather than the pH. (SG is listed on the chart posted)

The electrolyte is roughly a 75/25 mixture of water (H2O) and Sulfuric Acid (H2SO4) and during the normal discharge process, sulfate ions from the acid combine with the lead and lead dioxide plated to form lead sulfate, releasing electrons in the process. When the sulfate ion is removed from sulfuric acid, water is left behind. During the charge process, sulfate ions from the lead sulfate on the plates picks up electrons and combine with water in the electrolyte to reform as sulfuric acid.

Also during the charging process, electrolysis occurs and some of the water in the electrolyte decomposes into Hydrogen and Oxygen gasses and escape into the atmosphere. (That is the bubbling you hear). Only water is lost, so only water needs to be replaced.

Originally Posted by jonequest

Since I seem to have overfilled them slightly by adding water before charging sometimes, and have obviously lost some electrolyte is there a way to get the acid percentage level right again?

Since you have been losing both water and acid in the overflows, you might be able to regain some battery performance by adding battery acid for an auto store instead of distiller water when you fill your batteries.

The battery acid typically found in auto stores has a SG of 1.265, which is lower than the 1.270 mix put in the USB batteries at the factory, but it is still higher than the 1.23x the electrolyte in your batteries at the present.

Since there is about 36 quarts of electrolyte in your 48V battery pack and you probably only have to replenish a few ounces per month, it will take quite a while to get the SG back to where it would have been without the spillage.

If you try it, remember sulfuric acid is exceedingly dangerous to handle. Wear a face shield, gloves and cover all exposed skin.

[jonequest]

Johnnie B - Thank you for the very informative response to my issues. I think it makes sense. The batteries are weak from the lower acid ratio due to slow loss. I also just realized after 4+ years that I have to water after I charge only. I have learned to leave the water a bit below the fill well. I used to fill it to the fill well which I now see was way too much. I think I was so paranoid about low water I caused the overflow problems. I plan to get a little bottle of acid, remove a bit of water acid from the batteries, then add a little at time, and use a hydrometer to see when they are acidic enough. What procedure would you recommend to test acidity? Add a bit of acid, then charge and then test with hydrometer? Or maybe charge then add acid later, etc.?

[JohnnieB]

I would start by doing a series of back-to-back charges to get them as fully charged as possible with the existing electrolyte. After about a week or so of initiating charge cycles on batteries that have not been discharged, or only modestly discharged since the last charge cycle, should convert all the lead sulfate that is convertible, back into sulfuric acid and the SG will be at the highest it is likely going to get.

The most accurate way typically used to measure SG of battery acid is a refractometer, but a hydrometer will suffice.
This is what I use: https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1

The bulb type hydrometer would also come in handy removing some of the electrolyte from the cells.

How much to remove depends on the starting SG and the SG of the what is going to be added. The problem is that we don't know how much liquid the cell holds. According to US Battery, their four grades of 8V cart batteries held anywhere from 5.89qt to 6.82qt of electrolyte, so knowing the model number of your batteries will narrow it down.

Always test the SG after the batteries are charged.

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Again, H2SO4 is dangerous stuff, so be exceedingly cautious.

[jonequest]

I have the 8VGC Battery. I will definitely be careful with the acid. I have gloves and goggles in my garage.

[JohnnieB]

The US8VGC battery has an electrolyte volume of 6.37qts.