Battery Experiment.

[Uricanejack]

Problem I was away for a while early last season while boat was on mooring. Returned to flat batteries. Got the boat running. Initial both charged up to around 13 volts. (The meter in boat tool kit just a cheap analogue)
No 1 battery charged up and recovered. Holds the Charge is still working stated the boat the other day. Got her going even when freezing out. No 2 Battery wouldn't hold a charge more than an hour or so. Never been able to start the boat again. The other identical battery has been OK ever since. Have kept it as engine start battery. Used the NFG battery for lights ect at night at anchor wouldn't charge up much above 12 volts most of the season but would keep a light and gas solenoid on for an hour or two in the evening.
Obviously I need a new battery. I should just go get a new one.
But I thought I'd try an experiment.
Has anyone ever tried to revive one. I have seen all sorts of Bo11ocks about batteries on the internet.
Some involving Epsom Salts and Aspirin.
The alternator hasn't worked. My charger probably won't work. It's a cheap basic run of the mill intelligent charger with 6 amp or 2 amp setting.
Also these supposed pulse chargers. mixed opinions. range from a scam to they work a bit. I was thinking of trying one out. But before I do I will try and see what a regular charger on the low rate setting for a day or two will do. .
If I had an old stupid charger. I might be able to over charge it . But I must have chucked it out.
Battery an Interstate Marine/RV Deep cycle SRM-27 600 CCA 750 MCA Date April 14
Part No SRM 27 Marine Cranking AMPS 750 Reserve capacity 160.
Current Voltage 10.28.
Cell 1 SG 1225
Cell 2 SG 1200
Cell 3 SG The hydrometer failed to float went beyond scale. hydrometer does just float in tap water.
Cell 4 SG 1175
Cell 5 SG 1180
Cell 6 SG 1180

Current Diagnosis NFG needs replaced. Odds are nothing will work. But I've got nothing better to do.

Anyone ever revive a battery? or just bin it. Or in my case trade in and get a bit of a discount.

 

[VicS]

I would say that one cell is completely dead ( shorted out ?????) and that any attempts to revive it will be a complete WoFT.

 

[peteK]

When you do sort things out use a solar panel to keep it charged not worth all the faffing around for the sake of less than £30.

 

[Uricanejack]

I would say that one cell is completely dead ( shorted out ?????) and that any attempts to revive it will be a complete WoFT.

I suspect you are right. I will let you know if there is any change.

 

[fredrussell]

A while back I thought I would try to revive a very tired 50 a/h car battery with my very intelligent CTEK charger. They make great claims about their chargers possibly being able to 'do a Lazarus' in such cases. Unsurprisingly, battery was not revived by the charger.

 

[Uricanejack]

When you do sort things out use a solar panel to keep it charged not worth all the faffing around for the sake of less than £30.

I had a small portable solar cell on my previous boat. I kept it on the same mooring. It was a small 24ft boat with an old outboard and no charging system. A standard car battery for lights and radio.
I found it didn't do much for me. It was about 10 years ago. I didn't use a lot of power a couple of trips home or an occasional night in a marina kept it charged. Never need to start a motor though.
The little solar panel didn't seam to make much difference. They have probably improved a lot since then.
My main reason for not putting them on my current boat. Where would I put them.
It is a 35ft boat.

 

[PaulRainbow]

I would say that one cell is completely dead ( shorted out ?????) and that any attempts to revive it will be a complete WoFT.

I agree in this case.

I have a small Accumate charger that is typically used to maintain batteries over Winter on things like Motorbikes, Jet Skis, classic cars etc. This has recovered many "dead" car batteries that would not otherwise charge up, just leave it on for a couple of days and Bob's your uncle.

Don't think for a minute it will work in the OPs case and they aren't cheap so you'd need more use than reviving one battery to justify buying one.

 

[RichardS]

A while back I thought I would try to revive a very tired 50 a/h car battery with my very intelligent CTEK charger. They make great claims about their chargers possibly being able to 'do a Lazarus' in such cases. Unsurprisingly, battery was not revived by the charger.

I posted a few weeks about about running an old battery which was struggling to turn over a car starter motor on a big engine, despite being apparently fully charged on the conventional cycle, through the CTek "recondition" cycle.

It took 3 or 4 hours to complete but the battery was transformed! And here we are, a few weeks later, and it's still spinning the engine like a good 'un, and with the warmer weather approaching in will certainly last through to October at the earliest. :encouragement:

Of course, it all depends on exactly what is wrong with the battery and I doubt that a shorted cell can every be recovered.

Richard

 

[lpdsn]

My main reason for not putting them on my current boat. Where would I put them.
It is a 35ft boat.

Solar panels are much cheaper than they were ten years ago. You don't have to mount them permanently. I have a cheap 100W panel that I just tie on the coach roof when I need to. It's usually stowed away in a cabin somewhere when not needed.

 

[lw395]

Even if you don't need much from it, I think it is pretty dead.
When you only need a bit of low load capacity, like running a few lights for an hour, a battery that's no longer good to start a car can often be got from a garage for the price of a beer.
I had one in my lockup which was discarded by another yacht owner. It ran a few LED lights for long enough to rummage in the shed. Charged by a 5W solar panel. It did the job for a few years.

 

[Daydream believer]

Is the battery supposed to have sulphuric acid in it. if so, can you get some stronger stuff & stick some in

 

[William_H]

I had a small portable solar cell on my previous boat. I kept it on the same mooring. It was a small 24ft boat with an old outboard and no charging system. A standard car battery for lights and radio.
I found it didn't do much for me. It was about 10 years ago. I didn't use a lot of power a couple of trips home or an occasional night in a marina kept it charged. Never need to start a motor though.
The little solar panel didn't seam to make much difference. They have probably improved a lot since then.
My main reason for not putting them on my current boat. Where would I put them.
It is a 35ft boat.

Yes mounting and location of a solar panel is the biggest problem. You need to mount the panel angled towards the south and you need to have an amp meter (even temporary multimeter) to confirm you are charging the battery. Always room for a fault in wiring or panel. From there you just have to believe that about 1/3 amp for 6 to 10 hrs per day will be good for the battery. Of course if you have a swing mooring angling the panel to the south can be difficult. Horizontal suits all directions but is very inefficient. With a small panel it is easy to find a place on top of covers etc to get some sun and which can be stowed away when you are on board. That is what I do. Yes yo0u do need a new battery. olewill

 

[Uricanejack]

Voltage went up to 12. 5 after 5hr but dropped while I was reading it as soon as it was disconnected. No noticeable change in density.
Never reached 12.5 again.
After approximately 24 hours charging at 2 amp.
The temp of battery never rose. Just felt by hand.

Voltage read 11.8 dropped quickly as soon as charger disconnected.
After checking all the cell density Voltage steady at 10.88 V.

Cell 1 SG 1250
Cell 2 SG 1255
Cell 3 Now floats well of scale about similar level to tap water. SG 1000 ish
Cell 4 SG 1250
Cell 5 SG 1250
Cell 6 SG 1250

The Hydrometer color changes from white indicating Fair to Green indicating charged at 1250.

If I remember right from way back at high school. a lead acid cell will only hold up to about 2.2 or 2.3 Volts. Max 2.5.
5 x 2.2=11
So it would appear 5 cells are pretty close to fully charged. No 3 Cell NFG. And Unlikely to change.

If the problem was being just being sulfated. It might have made a difference. So Cell 3 is 100% sulfated or shorted or just 100 NFG.

The cheapest version of one of those pulse chargers is 45 bucks. or 90 bucks a new battery 140 bucks less what's left of the pro rated warranty.

Not worth trying.
If I can find an old dumb charger I might see what if anything it can do. probably nothing.
Left it on charge. Till I head for the store.

 

[Uricanejack]

Is the battery supposed to have sulphuric acid in it. if so, can you get some stronger stuff & stick some in

Yes I believes so. Trying to remember high school chemistry. The problem with the NFG cell. density its pretty much just H2O. The Sulphur having reacted with the lead to form lead sulfate coating over the plates.
The other cells have gone back to being acid. Not sure where I would get sulfuric acid. Break into a high school chemistry lab. or find anther old NFG battery which has some.
The safety warning on the battery specifically says don't add sulfuric acid. I think I remember hearing pouring acid into a battery can be a bad idea. If you don't know what you are doing.
Not sure what would happen If I tried that. I think it would be ok if you had a nice fresh new isolated battery with clean lead plates. Adding acid to an old cell with lots of sulfur on the plates.

My guess could be nothing or a big bang. Not to sure which.

This is where some of these other crazy internet ideas come into play. One of which is adding Epsom salts. Or Aspirin. What the hell its supposed to do I don't know. Start a reaction to beak down the lead sulfate. But you wont end up with sulfuric acid.
And I cant remember what actual chemical Epsom Salt is.

Magnesium sulfate MgSO4

 

[ghostlymoron]

I've seen a video on rejuvenating batteries. I think Epson salts were used to dissolve the sulphation, the emptied out and fresh acid added. It apparently worked but I've not tried it.
My problem is I've no understanding of what happens when a battery fails. When a cell is said to short out, what happens? What is sulphonation? Is it just a deposit on the surface of the plates? Can it depends dissolved chemically? If the sg of a cell falls to unity, where has the SO3 gone to?
Generally, when a battery starts to fail, i just replace it but wouldn't mind emptying it and pickling it with something.

 

[lw395]

You used to be able to get 'Batt Aid' pills to put in batteries.
There are some electronic 'desulfators' around. I built one from a kit.
Basically it generates a short pulse of up to about 70V repeatedly.
After a while, the pulse got smaller, implying that the battery was absorbing it better.

Did it do any good?
Maybe. In terms of a knackered old battery being a bit more useful for undemanding projects.
But I don't think the battery was ever going to start my motorbike again.
In the UK you can buy battery acid mail order BTW!
A lot of motorbike batteries are sold 'dry', and filled at the bike shop or by the rider.
I've always got the acid with the battery, but possibly a motorbike dealer might sell you acid?

 

[Topcat47]

My Ctek motorbike charger has a setting for correcting sulphation. It's fully automatic. I connected it to my "dead" 85ah boat leisure battery and left it for a week. The battery is back up to 12.5v and holding it's charge. I've also used it on my old weary 70ah starting battery and this too has had something of a revival, although it does drop off if left to it's own devices. I don't let it fall below 11.8v. The "so called" intelligent charger I use on the car had no effect whatsoever.

In service, I have a couple of 2.5w Maplin panels that maintain the battery voltages well between trips.

 

[ghostlymoron]

"In service, I have a couple of 2.5w Maplin panels that maintain the battery voltages well between trips."
5w is hardly enough to make up for self discharge.

 

[Topcat47]

They work for me, as does the 1.5w panel on my son's car.

 

[savageseadog]

The best snake oil for batteries is Ethylenediaminetetraacetic otherwise known as Tetrasodium EDTA.

As a yachtsman and mariner I just don't see the point of taking any chances with old batteries that may or may not be OK. My view is buy new batteries and be sure you're not going to be caught out, it's not worth the risk.