Interesting EDTA happenings

[whatsnext]

After Pepa asked me about my EDTA experiments I decided to look around for my SpG tester. What I fould next to was the first battery that I used EDTA on, with the caps off. It's a 12 volt deap cycle FLA trolling motor battery. The electrolyte level was very low, due to evaporation I guess, and required about 1.5 pints to get to the correct level. It read 6.4 volts after filling so I was expecting the worst but after charging it up with my Schumacher speed charger it's acting like a perfectly good battery again. No visual signs of sulfation, pulled my load tester solidly into the green, and even allows the charger to auto switch into 30A mode. Very suprising as the battery has been sitting for at least a year and a half. I was really expecting it to be quite dead. Usually a nice fresh battery has very fine bubbles when charging while a heavily sulfated battery will show larger bubbles under charge. This neglected battery acts like a nice fresh battery after this abuse. I'll put a good charge/discharge cycle on it for the next few nights to see how it behaves.

John......

[pepa]

that is real good news John, thanks pepa.

[Titantornado]

WOW!  That is a good bit of news!  This stuff almost makes it seem like the lead-acid batteries will be more tolerant of abuse like a nickle-iron type cell do.

So what do the experts here think?  Could this be the Holy Grail for lead-acid batteries?  Should I be getting excited about this as I feel I am, or am I missing something else here?

[stephent]

Well, I wouldn't call it the Holy Grail exactly.

It won't stick the flaked off sulphated crud back onto the plates.

It won't put plate material back into place after a shock (physical) knocks it from it's place.

It won't put back bulged plates. But it can help reduce sulphation on the plates and get rid of some of the coating that makes a bit higher resistance to charging/discharging.

It can get rid of the sulphated coating on a bit of flaked off lead laying down on the bottom and make it a real good "short" across a set of plates if it's in just the right spot--this can make the battery a bit warm--or possibly even puking hot acid out of the box from very mild to wild speeds.

But in a reasonably good shape battery (excluding sulphation) --there's positive results from using it.

In sulphated batteries, it has led to some form of usefulness after a few charge/ discharge cycles.

It's cheaper then a new battery and there's more then a bit of research proving it can help prolong the life of a battery.

It's certainly better then using cadmium based stuff (the old VX6) for the same effect.

But as far as grabbing the suphate from the lead and then just giving it up freely back to the acid, I don't believe that's a 100% process.

It's certainly cheaper to use a bit of it and gain the further use of a sulphated battery--but somehwere way back in my mind there's a question about ion exchange mixing with the word "inhibit"---ahhhh--never mind---I just need some more coffee--it's been a long week already for me.

[ghurd]

Anyone have an idea if EDTA could or should be used as a preventative measure?

Say 10% or 25% of the recommended dose BEFORE the battery has signs of troubles.

G-

[whatsnext]

When I put it into my T-605's it seemed to change the way the batteries discharged. The voltage remained more constant during discharge after adding EDTA. So I'm sure this changes chemistry somewhat and that would make it an all or nothing affair as you probably wouldn't want batteries with different chemistries in the same string. The only way to find out if it's worth putting in a new battery would be to do some sort of test to compare a new VS new+EDTA battery and I really don't want to go out and buy any new batteries. My 605's were quite sulfated and would almost boil over when charged. After EDTA they act like good bateries and when you look into the cells the plates don't appear to have any sulfation. I brought the trolling motor battery up to full charge overnight but didn't have time to check SpG this morning as I was running a little late. I'll do it when I get home tonight.

John.....

[Slingshot]

Is this the same stuff that is used as a food preservative?

[Flux]

The one that seems to work for batteries is the tetra sodium salt. Most sources will not commit themselves beyond saying it is EDTA.

It certainly is a food preservative in one of its forms.

They want the earth for a couple of spoonfuls of the tetra sodium sort here, would be cheaper to import from N. America.

Flux

[whatsnext]

I'm pretty sure this version is used as preservative in wines here in the states.

John

[Slingshot]

Sounds like you might be able to buy it cheaply from winemaking suppliers?  Maybe ten cents a sackful