How Do Lead-Acid batteries die?

[wdfifteen]

I effed up and let the water level get low - well below the plates - on the 8 volt batteries in Mrs WD golf truck. It runs on 6 batteries, 8 volts each, for 48 working volts.



I filled them to the appropriate level with distilled water and hooked up the charger - no go. The charger won't begin to charge unless it gets the right signal from the battery pack - supposedly it needs to see something like 40 volts. I've been here before, so I charged each individual battery up to 7.8 or 7.9 volts except one which I could not get above 7.5. Even with 45 volts+ across the battery pack, the charger won't recognize the batteries. The on-board volt meter reads normal, but the cart is sluggish - not operating normally.
Did something get damaged in the batteries that simply charging them cannot fix?

[Crowbob]

Yes, probably, but maybe not, no.

[flatbutt]

Did the plates get salted by going dry?

[Jims5543]

The way I understand it the electrolyte is bad and needs to be replaced.

I had a customer that owned a pool company when the housing crash hit they tried to start up a battery rejuvenation company targeted towards golf carts and boats mostly.

I wondered what they were doing, seems they were replacing the electrolyte in the batteries.

https://www.zoro.com/phcc-pro-series-battery-acid-6-qt-g-pack/i/G3148984/feature-product?gclid=Cj0KCQjw0a7YBRDnARIsAJgsF3Ob7wWoMHPO 2cK7bT_0Jm9_z8S_eUS1C83iWzFy6MmcN4iDgcKWN6UaAnygEA Lw_wcB&gclsrc=aw.ds

If you google restoring a lead acid battery there is a ton of info.

[nota]

lead acid battery do not like total discharge or over charging or exposed plates

some claim a de-sulfide charger will restore some function
I have one but have not had much luck with it

btw each cell should charge to 2.1 v or 8.4 for a 8v 12.6 for a 12

if they are in warranty return if out replace

do not run till dead or even past 50% charge
recharge after any use and they should live on a trickle charger if not used often

[red-beard]

They die by the plates shorting out. By drying out, you have several shorted cells.

How deep do you discharge the batteries normally and how often does she discharge the batteries? There are advanced lead acid batteries that will last a lot longer for only about 20% more money. Also, the charger can have a big effect on life.

[GH85Carrera]

Back in the "good ol days" a battery usually just got weaker and weaker, and you knew it was time to replace it. Now the new generation of batteries usually just die and instant death. The last three batteries on my El Camino were fine one moment, and would not even let me jump start the car with another car providing the electricity. No sluggish starter, no warning, just dead. Only replacing the battery will help.

[Cajundaddy]

Sulfated plates or shorted plates are common ways to damage a battery. Also discharging them below 50%.

The trick with cart batteries for best life:

- Never discharge them below 50% capacity.
- Keep them on a smart battery maintainer designed for your voltage and formulation when not in use.
- Check the levels monthly and don't expose the plates.

[wdfifteen]

Originally Posted by red-beard

They die by the plates shorting out. By drying out, you have several shorted cells.

How deep do you discharge the batteries normally and how often does she discharge the batteries?

We don't normally discharge them deeply. They are on the charger every night except for the past couple of weeks, when we couldn't get the cart next to it. The only time we have ever discharged them to the point you could feel it in the function of the golf cart was a few days ago. Can one bad episode totally roach otherwise good batteries?
To some extent this is an academic question. The batteries are at least 6 years old. Until recently they've been taken care of, but I understand 6 years is a good run. I'll be buying new ones.
But before I spend $1200 on a new battery pack I'm wondering if dropping a Viagra in each cell would stand them up.

[dad911]

can you use 4 cheaper 12v batteries in series? 4x12v=48v.

[wdfifteen]

Originally Posted by dad911

can you use 4 cheaper 12v batteries in series? 4x12v=48v.

I'm not sure the on-board computer or the battery charger would recognize 4 12s. It seems to be pretty sensitive.

[nota]

3 to 5 is what most get at 6 you did good

some are using el car batterys out of wrecks to get cheap li-po's packs
but they still are expensive and need controllers and chargers too

no quick fix esp if low water corrosion

8x6 6x8 4x12 2x24 all equals 48v but amps matter for range
4x12v will likely be way shorter range with less amps total
unless priced like the 8v bigger guys
the desulfide tricks can take lots of time weeks and is not for sure
dumping acid is dangerous cleaning sludge may work for a bit or may not

[porsche tech]

As said above, sulfated plates. The scaling falls to the bottom and shorts out the plates. The easiest thing to do first is a specific gravity test to check to find the faulty cell and start with replacing the battery with the faulty cell. That being said, the rest of them are probably not far behind.

[Zeke]

A long time ago I used to drain the battery and hose the crap out of the bottom with water and a a nozzle. Not very safe work and really not many convenient places to do this, especially these days. But, with new electrolyte the batteries would come to life and last another year or so.

That is if you can get the reddish gunk off and out of the bottom of the battery. There is a site called "Battery University" that I read a bit on but mostly over my head. In fact they point out that a lot of battery phenomena are unexplained.

I wouldn't give up until you try some of the tips and tricks listed on that site and others.

[T77911S]

battery university..good site.

I have 40 batteries in my 40kva UPS at work I maintain. 480v
one of the checks I do is resistance of the battery. as the internal resistance goes up the battery goes bad.
these are sealed batteries.

as said I would try new electrolyte.

[unclebilly]

I have also had luck completely discharging batteries by connecting them to a headlight over night. Then charging them backwards to knock the sulfur off the plates. I have run them this way and have also discharged them again and charged them correctly.

[Por_sha911]

^
Huh?
"headlight nicer night" ?
"charging them backwards" ?

[unclebilly]

Originally Posted by Por_sha911

^
Huh?
"headlight nicer night" ?
"charging them backwards" ?

Yah, I have fat fingers.

[wayner]

Originally Posted by porsche tech

As said above, sulfated plates. The scaling falls to the bottom and shorts out the plates. The easiest thing to do first is a specific gravity test to check to find the faulty cell and start with replacing the battery with the faulty cell. That being said, the rest of them are probably not far behind.

One of the significant differences with a deep cycle battery is that they have a deeper case below the plates allowing scale to fall beyond the plates and not short them out

That’s one reason deep cycle batteries last longer
But deep cycling is part of the issue

[Zeke]

Originally Posted by porsche tech

As said above, sulfated plates. The scaling falls to the bottom and shorts out the plates. The easiest thing to do first is a specific gravity test to check to find the faulty cell and start with replacing the battery with the faulty cell. That being said, the rest of them are probably not far behind.

The way you say that sounds like you are suggesting be able to get inside the battery case and R & R a cell. Or you could be saying replace the faulty battery in the bank of batteries.

???