So I am going to try my hand at reconditioning lead acid batteries...

[DXHum]

Unfortunately, "set it and forget it" does not apply to lead acid batteries. However, I am guilty of just that.

I've been using Duralast deep cycle marine batteries from AutoZone. And while they work well when fresh and new, I need to learn to keep after them so that they remain reliable and meet expected levels of performance.

So now, I have two Duralast deep cycle marine batteries which I will try to restore.

I've warmed 1 gallon of distilled water in a pot and added a 3 pound bag of epsom salt. Thoroughly stirred and dissolved, I've placed the mixture back in the 1 gallon jug (from distilled water) and set it aside.

I'll have to stop there as my protective face and body wear has not arrived. When it does, I will:

1. Drain all acid from both batteries and store in a bucket.
2. Rinse the battery with fresh water.
3. Using a scope, conduct an internal examination of the battery condition, making any necessary corrections.
4. Filter the used battery acid into a second, clean container.
5. Blend the clean acid with the epsom salt solution.
6. Refill the batteries.
7. Apply the charger ( fill caps off to avoid explosions).
8. Upon reaching voltage, perform a load test.

Anyone else ever try to restore an old lead acid before?

Thank you for input in advance.

Dx

 

[Checkthisout]

Unfortunately, "set it and forget it" does not apply to lead acid batteries. However, I am guilty of just that.

I've been using Duralast deep cycle marine batteries from AutoZone. And while they work well when fresh and new, I need to learn to keep after them so that they remain reliable and meet expected levels of performance.

So now, I have two Duralast deep cycle marine batteries which I will try to restore.

I've warmed 1 gallon of distilled water in a pot and added a 3 pound bag of epsom salt. Thoroughly stirred and dissolved, I've placed the mixture back in the 1 gallon jug (from distilled water) and set it aside.

I'll have to stop there as my protective face and body wear has not arrived. When it does, I will:

1. Drain all acid from both batteries and store in a bucket.
2. Rinse the battery with fresh water.
3. Using a scope, conduct an internal examination of the battery condition, making any necessary corrections.
4. Filter the used battery acid into a second, clean container.
5. Blend the clean acid with the epsom salt solution.
6. Refill the batteries.
7. Apply the charger ( fill caps off to avoid explosions).
8. Upon reaching voltage, perform a load test.

Anyone else ever try to restore an old lead acid before?

Thank you for input in advance.

Dx

Cook the battery with the caps off for a bit and look at each cell.

The first cell to start to gas is the bad one and closer inspection will most likely reveal trashed, crumbling plates.

If equalization alone won't fix it, the battery is done.

I would instead use the time to get a second job and just use the extra cash to buy some lithium cells and diy a battery.

 

[sunshine_eggo]

Cook the battery with the caps off for a bit and look at each cell.

The first cell to start to gas is the bad one and closer inspection will most likely reveal trashed, crumbling plates.

If equalization alone won't fix it, the battery is done.

I would instead use the time to get a second job and just use the extra cash to buy some lithium cells and diy a battery.

Damn it... beat me to it... more succinctly too!

Would add documenting the specific gravity of each cell after following a full charge before starting.

 

[DXHum]

Cook the battery with the caps off for a bit and look at each cell.

The first cell to start to gas is the bad one and closer inspection will most likely reveal trashed, crumbling plates.

If equalization alone won't fix it, the battery is done.

I would instead use the time to get a second job and just use the extra cash to buy some lithium cells and diy a battery.

If I wanted, I could easily drive to the store and buy two new batteries. This is more about educating myself.

 

[sunshine_eggo]

If I wanted, I could easily drive to the store and buy two new batteries. This is more about educating myself.

The fact that your considering this process indicates you haven't educated yourself.

Do your research. Find a reference that demonstrates before and after testing in a meaningful way, i.e., battery is rated for X, tests Y and after the process, it tests Z.

You won't find it.

How did your equalization charges go?

 

[DXHum]

Damn it... beat me to it... more succinctly too!

Would add documenting the specific gravity of each cell after following a full charge before starting.

Yeah... I understand that. Good to make note of. Thanks!

 

[DXHum]

The fact that your considering this process indicates you haven't educated yourself.

Do your research. Find a reference that demonstrates before and after testing in a meaningful way, i.e., battery is rated for X, tests Y and after the process, it tests Z.

You won't find it.

How did your equalization charges go?

I haven't begun the process. I'm waiting on my safety gear.

There are many ways to go about reconditioning a battery. And I would be interested in hearing what your procedure is for reconditioning a battery.

Lastly, if there is something wrong with my process, I'd like to hear your thoughts.

The process I've selected has yielded satisfactory results for others who have tried this. And for $50.00, it was worth a chance.

 

[sunshine_eggo]

I haven't begun the process. I'm waiting on my safety gear.

The process you're using is what farmers do to tractor starter batteries to get them to start. It is not what someone does to power storage batteries to increase capacity.

There are many ways to go about reconditioning a battery. And I would be interested in hearing what your procedure is for reconditioning a battery.

Nope. There aren't. there are two: 1) equalization charges and 2) cleaning/electrolyte replacement.

The issue with #2 is you still have shitty degraded plates in the battery, and you're polishing a turd.

Lastly, if there is something wrong with my process, I'd like to hear your thoughts.

next post.

The process I've selected has yielded satisfactory results.

Please cite a source that demonstrates QUANTITATIVE improvements in capacity.

 

[sunshine_eggo]

8X used T-1275 from golf cars, 2-4 years old. 1-4 were older and from one cart, 5-8 were newer and from a different cart:

Battery	Volts	CCA (665)	IR	SoH	100A VL	SG1	SG2	SG3	SG4	SG5	SG6	SGd	RCi	RCf	Ahi	Ahf	SoHi	SoHf
1	12.65	499	6.23	63%	11.38	1.250	1.250	1.250	1.250	1.260	1.250	0.010	219	235	91.5	98.4	78%	84%
2	12.70	524	5.94	66%	11.47	1.260	1.265	1.260	1.260	1.260	1.250	0.015	235	249		104.1	84%	89%
3	12.52	493	6.30	62%	11.30	1.250	1.250	1.225	1.230	1.245	1.220	0.030	180	209	75.3	87.7	64%	75%
4	12.58	523	5.95	66%	11.37	1.250	1.255	1.255	1.200	1.255	1.240	0.055	201	228	84.4	95.9	72%	81%
5	12.96	543	5.74	69%	11.67	1.250	1.260	1.260	1.250	1.250	1.250	0.010	205	270	89.8	112.9	73%	96%
6	12.95	531	5.86	67%	11.67	1.260	1.260	1.250	1.260	1.260	1.245	0.015	266	266	111.7	111.6	95%	95%
7	12.89	540	5.77	68%	11.65	1.250	1.250	1.260	1.260	1.250	1.225	0.035	238	256	99.6	107.3	85%	91%
8	12.95	513	6.07	65%	11.66	1.260	1.260	1.250	1.250	1.260	1.260	0.010	220	254	92.2	106.5	79%	91%

Volts, CCA, IR and SoH values are from a digital load tester for comparison purposes.

100A VL is the lowest voltage observed with 15 second 100A load test

SG1-6 are the specific gravities of the cells.

SGd is the difference between the min and max SG.

RCi is the initial reserve capacity determined by full charge, 25A discharge to 10.5V.

RCf is the final reserve capacity using the same method.

Ahi is the initial Ah reading reported by the 25A discharger.

Ahf is the final Ah reading reported by the 25A discharger.

Note that these are 150Ah batteries, but that is only for a C20 discharge of 7.5A. Since I was discharging >3X higher than this, the capacity will be lower.

Reserve capacity, RC, is the number of minutes a battery can deliver 25A above 10.5V. It is published for this battery, so a state of health based on RC is just as valid as one based on a C20 rate.

In between RCi and RCf, I conducted equalization charges to 16.4V following Trojan's published instructions.

According to Trojan, inability to attain 1.278 or if SGd varies by 0.030, equalization charges are needed.

As you can see, based on those criteria, all batteries needed it.

Absolute improvements in reserve capacity were from 6 to 23%.

While I measured SG, I did not record SG as there were a lot of readings. Basically when I could get at least one cell above 1.278 and all cells within 0.030, I stopped. Each battery received 1-3 equalization charges to achieve the final results.

 

[sunshine_eggo]

The process I've selected has yielded satisfactory results for others who have tried this. And for $50.00, it was worth a chance.

Find one of those Youtube videos of folks in India "refurbishing" batteries. Watch very closely. If you really pay attention, you'll see that they're installing new plates and separators.

 

[time2roll]

Those batteries are not really designed for consistent deep cycling.
I believe you will find refurbishment to be a fools errand.

 

[sunshine_eggo]

I will say if you want to do this just for shits and gigglez, go for it.

However, you really need an objective way of determining the results in a way meaningful for their intended use.

If you're willing to charge/discharge by powering a load for X minutes before the process and then repeat the same charge/discharge by powering a load for Y minutes, then you have something meaningful to document. Otherwise, it's going to be anecdotal at best.

 

[DXHum]

Find one of those Youtube videos of folks in India "refurbishing" batteries. Watch very closely. If you really pay attention, you'll see that they're installing new plates and separators.

Anyone who follows instructional videos from India is asking for trouble. I'm not interested in doing what they show. It's sloppy, unprofessional and never meets the standards that I set. Nope, I wouldn't chance anything I see in those videos.

 

[DXHum]

Those batteries are not really designed for consistent deep cycling.
I believe you will find refurbishment to be a fools errand.

Again, this is about experimentation and learning. A fool's errand would be buying new batteries when for a few dollars, you can refurbish. Again, it may not work, but the value in education is worth the time and effort to me.

 

[DXHum]

I will say if you want to do this just for shits and gigglez, go for it.

However, you really need an objective way of determining the results in a way meaningful for their intended use.

If you're willing to charge/discharge by powering a load for X minutes before the process and then repeat the same charge/discharge by powering a load for Y minutes, then you have something meaningful to document. Otherwise, it's going to be anecdotal at best.

Why not give me an opportunity to give it a try? When I'm done, I will report back for further discussion. Sound like a good plan?

 

[sunshine_eggo]

Anyone who follows instructional videos from India is asking for trouble. I'm not interested in doing what they show. It's sloppy, unprofessional and never meets the standards that I set. Nope, I wouldn't chance anything I see in those videos.

While I generally agree with the sentiment, it does not apply in this case.

What they do in those videos is dramatically more sensible and effective than what you plan to do.

Again, this is about experimentation and learning. A fool's errand would be buying new batteries when for a few dollars, you can refurbish. Again, it may not work, but the value in education is worth the time and effort to me.

One could also indicate it's a fool's errand to spend a even a little money and a bunch of time on a process that has no documented quantitative benefit.

Why not give me an opportunity to give it a try? When I'm done, I will report back for further discussion. Sound like a good plan?

LOL... pretty sure I literally said that in my text you quoted; however, a "report back" must include some objectively meaningful results, i.e., before and after capacity tests of some form.

If you just need them to hold a higher voltage and crank an engine, and sit around on float, you'll probably be successful. If you want them to be used for power storage and cycling, buy new batteries.

I'll ask again... how did your equalization charges go? You haven't answered, so I can only assume you have not done any equalization charges - the one thing manufacturers recommend to restore lost capacity. This actually "reconditions" the plates to some extent and would actually enhance your chances of success with the process you propose.

Once more... Equalization charges?

 

[Checkthisout]

Why not give me an opportunity to give it a try? When I'm done, I will report back for further discussion. Sound like a good plan?

Yes, of course give it a shot. I'm a fan of "fawk it, run it and see what happens".

The consequences are low.

Even if it works, I wouldn't trust the battery after that. I don't want to get back from a 3 day hike and not have my 7 year old reconditioned battery not start my rig.

I maintain over 100 batteries and if sulfation is what's bogging the battery down, a nice cook on an old school charger generally does the trick.

You can check the plates beforehand. You can see if they are sulfated or starting to break down. Usually one cell goes bad while the rest are OK. (Usually). "Bad cell" generally means the cell is beginning to short which is why it's the quickest to start gassing.

I hate dealing with automotive fluids and the landfill already has more than a fair share of my clothes that had to be tossed because it looked like a platoon of moths attacked them a week or two after having to have wrestled a huge, leaky battery out of an engine compartment in a piece of equipment.?

 

[time2roll]

I do expect a favorable initial report. It is the the two month and further report that will be interesting.

 

[OzSolar]

You might gain something useful from the below threads.

I found this 22 yr old cell to be dead in my 48v battery pack. It's 24 years old now and honestly isn't doing too bad but has spent most of later years in float service. Still, I'm pretty sure I can still get 800 AH out of this 1104 AH battery bank.

I haven't put in back in service yet but I did just check it's resting voltage and SG. 2.15v and 1.260 isn't too bad for having been ignored for 6 months. I really do keep meaning to put it back in the pack but there's plenty of other things to distract me every day. That will be that actual test.

2V FLA cell failure

Did an equalize charge on my 48v Surrette pack this week. Found one cell with a SG of barely above 1.xx and about .3 volts lower than the others. After several more tries it still didn't budge pulled it out until I can try to do an EDTA treatment..... or maybe it's time to look at server...

diysolarforum.com

Ohms law is your friend

23 yr old 2v FLA cell still alive in the wild. Doing well actually. Last May (~8 months ago) I found this cell way under spec compared to his 23 counterparts. Pulled it, then wired around it, reprogrammed my inverter. Left alone until a few weeks ago. SG read was just over 1 and Voc was...

diysolarforum.com

 

[shopman]

It's not that "it may not work", more like it will not work. Take it from someone whom has tried all forms of reconditioning. EDTA, epsom salts, rinse wash and repeat, etc. Once they're sulfated they're dead. The Pakistanis know it which is why they replace the plates and trust me, if there was a more economical and reliable way of doing it that would be the route they would take. As someone else pointed out, the Duralast batteries aren't the greatest to begin with as they're not a real deep cycle battery. I'm all for experimentation though, so have fun!