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Baking Soda Desulfate?

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electricthot

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Years ago, I had a dead car battery that I brought back to life by emptying it, flushing all the sulfiric acid out of it with an upside down rinse with a garden hose, and then filling each cell for a short time with a baking soda/water rinse. I've got some dead (useless in my off grid system), golf cart batteries I'm going to try it on this morning. From the point of view of chemistry, in the strict absence of any residual sulfuric acid, what will the lead sulfate do when flooded with the baking soda solution? I ask this to get an idead of how strong to mix the solution--I don't want undergirding exposed when I'm done.
 
If the sulfate has crystallized then not much. But if the reaction loosen's and sheds to fresh lead the yes. I would think a long flush would be in order. Please post you results when you are done.
 
grizzzman said:
If the sulfate has crystallized then not much. But if the reaction loosen's and sheds to fresh lead the yes. I would think a long flush would be in order. Please post you results when you are done.
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Then you would suggest a stronger solution? There's another possibility. I have the first battery drained. If I don't rinse it, there will be strong reaction between the sulfuric acid and the baking soda. Like this, would the plates get a faster scouring, as it were? I have nothing to lose, and have multiple batteries I can try different methods on. And it seems to me, especially if I take the route just described, the battery should be well discharged, no matter which way I go.
 
electricthot said:
Years ago, I had a dead car battery that I brought back to life by emptying it, flushing all the sulfiric acid out of it with an upside down rinse with a garden hose, and then filling each cell for a short time with a baking soda/water rinse. I've got some dead (useless in my off grid system), golf cart batteries I'm going to try it on this morning. From the point of view of chemistry, in the strict absence of any residual sulfuric acid, what will the lead sulfate do when flooded with the baking soda solution? I ask this to get an idead of how strong to mix the solution--I don't want undergirding exposed when I'm done.
Click to expand...
First battery is on the charger. Next.....
 
electricthot said:
Years ago, I had a dead car battery that I brought back to life by emptying it, flushing all the sulfiric acid out of it with an upside down rinse with a garden hose, and then filling each cell for a short time with a baking soda/water rinse.
Click to expand...
I suspect 98% of the benefit is just dumping out the junk, rinsing out and putting in fresh acid.

I've not heard of using baking soda. I tried it with EDTA salt on a 2v cell (below). EDTA may pretty to close everyday Epsom salt but I won't pretend to be a chemist.

It was successful from a non-scientific view point. Totally dead battery before would hold a charge afterwards but I've not actually tested the amp hours yet. It's still alive today. Did that a year ago bur haven't put it back into service yet.

1104 AH 2V Cell that came out of my 48v flooded lead acid battery back that I installed in 2000. Still going today.

1708201987460.png
 
What will you replace the battery acid with?

IMO, the composition of the lead will determine the results. Newer batteries tend to have a lot of surface area to provide energy quickly for short periods, and look like a radiator. These batteries don't recover so well. I doubt something like this would recover well:
1708203227165.png
I think a decent deep cycle battery could do really well with this method. I wished I'd save a picture. Those batteries have less surface exposure since they release energy over a longer period of time. Hard to describe, but blocs with holes in them, kind of like Swiss cheese.

I found a lot of old articles of military issued batteries being in storage well beyond the expiration date that used the method you talk about to recover.
 
chrisski said:
What will you replace the battery acid with?

IMO, the composition of the lead will determine the results. Newer batteries tend to have a lot of surface area to provide energy quickly for short periods, and look like a radiator. These batteries don't recover so well. I doubt something like this would recover well:
View attachment 196250
I think a decent deep cycle battery could do really well with this method. I wished I'd save a picture. Those batteries have less surface exposure since they release energy over a longer period of time. Hard to describe, but blocs with holes in them, kind of like Swiss cheese.

I found a lot of old articles of military issued batteries being in storage well beyond the expiration date that used the method you talk about to recover.
Click to expand...
I strained the acid through 250 mesh, and reused it. These batteries were different in that one (Trojan 105) was quite old, and voltage was good but it had no power. Probably well crystalized. The other battery (Napa 8144) was manufactured in 2/18, but was well used in my off grid residence. It registered 4.01 volts, but could be charged higher. But it was not good enough to use in my battery bank.
 
electricthot said:
Then you would suggest a stronger solution? There's another possibility. I have the first battery drained. If I don't rinse it, there will be strong reaction between the sulfuric acid and the baking soda. Like this, would the plates get a faster scouring, as it were? I have nothing to lose, and have multiple batteries I can try different methods on. And it seems to me, especially if I take the route just described, the battery should be well discharged, no matter which way I go.
Click to expand...
Sorry for the late reply. My thought would to charge it before you did the procedure so as much back unto the electrolyte before dumping.
 
electricthot said:
Second battery is on the charger. We'll see. I'll be back....
Click to expand...
Didn't work, guys. the T-105 seems to have lost some. the Napa is still on the charger, but voltage doesn't seem to want to climb above 6.5. Nothing lost though, and some knowledge gained. I'm only doing this out of desperation for more battery power. Next payday will see a new 100aH AGM, and I should be fine then. The issue is low batts/=gas/gen right now. $. I'm having fun, though, learning a lot. From a very mis-matched set of batteries. The AGM is new, and one set of GC-2 are still strong...the rest are junk. But the junkies seem to give me a couple hours longer each night. As you can see, the AGM (100aH) and one set of Trojans 230aH) have a double shunt setup, with an isolator switch. One measures only charge (all resettable), and the other only discharge. At the end of a 24 hour period, I can see and compare at a glance how much each battery took in, and put out. I read that above, with two displays for each battery.
 

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electricthot said:
Didn't work, guys. the T-105 seems to have lost some. the Napa is still on the charger, but voltage doesn't seem to want to climb above 6.5. Nothing lost though, and some knowledge gained. I'm only doing this out of desperation for more battery power. Next payday will see a new 100aH AGM, and I should be fine then. The issue is low batts/=gas/gen right now. $. I'm having fun, though, learning a lot. From a very mis-matched set of batteries. The AGM is new, and one set of GC-2 are still strong...the rest are junk. But the junkies seem to give me a couple hours longer each night. As you can see, the AGM (100aH) and one set of Trojans 230aH) have a double shunt setup, with an isolator switch. One measures only charge (all resettable), and the other only discharge. At the end of a 24 hour period, I can see and compare at a glance how much each battery took in, and put out. I read that above, with two displays for each battery.
Click to expand...
Thanks for the update.
 
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