Battery Life Expectancy ?

[Markcuda]

You have wayyyyyyyyyy to much time on your hands

 

[Gale Hawkins]

You have wayyyyyyyyyy to much time on your hands

Hey it is just my new project of the week/month.

It was just Wednesday when I learned about the reversion polarity and it upset me that in all my reading on battery issues I had never ran across it.

Some of the reading on the subject will go like, "I can remember my father doing it when I was a kid. It did not always work but did more often than not."

What really got my attention was hoow old men accidently did it in the past come spring time on the lawn mower or old tractor after setting all winter.

It can not be done with most chargers purchased today. The fact the guy used the car in the link I posted today for two years with the polarity reversed was interesting.

What was very interesting was when he killed the battery two years later it reverted to factory polarity on its own based on his post. That would be some pretty strong force to cause that to happen.

Since I plan to flip these back that gave me hope it would be easier than this first reversal. I think I am going to get the polarity reversed finally. This morning all four after 13 hours of no charging was still reversed. After the third night one was at 11 volts and three others after two nights were just under 2 volts each.

I do not advise others to try this because it is a lot of work. Even if I "save" this old set for $300 I could just run to Wal-Mart and be done. The golf cart will run $700+ however.

 

[Gale Hawkins]

I picked up a neat way to find problem cells with the temp gun during this battery polarity reversing project. Sweeping the gun along the long side of a charging battery can reveal cells that are cooler/hotter than other cells.

On the project I have the batteries load testing at about the same level but as before the polarity reversed. They seem to mirror about the same SG per cell in a relative sense. I have just started the discharge/recharge cycling to see if that will help desulfate them more.

I am finding it takes a while to get the batteries charged enough to get more than 14v output from the chargers. The automatics are OK and I am running the Desulf Mode on them a lot but after getting all four somewhat equal in condition I have reconnected them in parallel and have them on the manual 40 amp wheeled charger ($125-$150 price range home shop version). Now on the 40 amp setting the output is about 30 amps @ 14.5 volts on the 300ah bank. From what I read it is hard to top off a battery unless the charger will output over 14.2v.

In the coming weeks I will continue to cycle and see if performance/SG improves.

Knows at this point is that one can get a battery to change polarity. Second is that battery polarity reversal DOES desulfate a battery in a visible sense.

Unknow if polarity reversal is practical.

Keep in mind these four group 24 75ah marine batteries where cores that never go returned a few years ago and no water was showing in some of the cells.

A charger that you could adjust the current and voltage would be a plus I think in the early stages. When the battery is at 2 volts a common charger will not be putting out 14.2v + which is needed. A charger that was adjustable for 2 to 24 volt output would be nice but the one I read about was $500+

Just using one charger to charge the entire bank makes it more simple. The 40 amp setting is fine for when I am around but I like to drop the manual charger to 10 amp setting when I am going to be away from the building. The 10 amp setting on the 300 ah bank is just a bit more than a trickle charger.

Oh I was hard charging one on a solo charger and forgot to check on it for a while and the side of the case read 172 F degrees. Now I can see where some black plastic has dripped down on to an internal connector bar so I about lost that battery from the testing group. The funny part is its performance has improved some. It may have gone into run away mode but I thought it had already did the burn off stage when normally happens.

Currently I plan to do about 10 discharge/recharge cycles before I do any SG adjusting in the cells that will not make it up to 1.26 SG.

 

[WilliamTO-35]

I'm not familiar with this reverse polarity battery restoration process, and I wish you luck. I also wish that you use caution . Batteries are, of course, high current devices , and can generate heat and hydrogen gas , accidental sparks, and contain sulfuric acid. Be careful ! Battery explosions are not that rare.

 

[Gale Hawkins]

I'm not familiar with this reverse polarity battery restoration process, and I wish you luck. I also wish that you use caution . Batteries are, of course, high current devices , and can generate heat and hydrogen gas , accidental sparks, and contain sulfuric acid. Be careful ! Battery explosions are not that rare.

As you can read from the top this is new to me too.

Removing the cell caps is critical to prevent hydrogen explosions since hydrogen requires a 3% level to explode. The sulfation burn off phase can go into 'run-away' (never did happen to me but I was on the look out for it) even after the charger is removed.

From the info I found it is best if done on working batteries when their run time decreases by 20% so there is not heavy sulfation to reverse.

What was cool in my last post was how sweeping an IR temp gun along the side of the battery when charging can show how all cells may not be responding the same which is not positive. Natually the cells on the ends tend to be a little less warm.

 

[Skyco]

Regarding the end cells- I've noticed for years that the end cells in functioning batteries tend to need water added more often. I've not been able to find out why though...puzzling since they would tend to be cooler and one would think they'd need less water replaced..

 

[Gale Hawkins]

Skyco that is interesting and I will look for that myself.

Using two head lights I ran the 300 ah rated (when new ) back down to 9.5 volts last night (12 hours) yet he lights were still burning fairly bright.

After a couple hours on the 40 amp setting the hand has almost dropped back down to near 40 after starting out at around 60+.

So far a side sweep with the temp gun is showing similiar readings for all four with the end cells about 10 degrees cooler.

 

[Gale Hawkins]

Guys I discharged the four batteries some today and put the charger on 10 amps (300 ah of batteries) and plan to leave them there for several days.

So far the same cells are weak as before the batteries polarity was reversed.

I can see they are less sulfated but so far these junk batteries are still junk.

The source I first posted said this process worked best when batteries lost 20% of their run time ability. These batteries had lost 60% of their run time then set unused for a few years.

I do plan to try it on a known good battery with all good cells but decreased run times with the same known load.

 

[Raspy]

Gale,

Back when I was in junior high school, in diesel shop, one guy accidentally hooked up a battery in reverse on a charger and charged it up. When discovered, we all looked in amazement and I've never forgotten it. I don't remember what we did about it.

Anyway, one of the things that can kill batteries, as I recall, is material falling off the plates and gathering below them. Finally the pile gets deep enough to begin shorting the battery. I understand that one of the differences between deep cycle and starting bats is the volume of sediment space below the plates.

I wonder, since you've seen a change in the appearance of the plates, and the batteries you are playing with are old and very sulfated, if you might have shorted batteries that will not respond to your treatment because of that.

Maybe you could rinse them out and replace the acid. If you do, take a hydrometer reading first and try to replace acid with the same reading, I guess.

You mentioned the difficulty of getting a high charge rate out of a charger, if I understood your remarks correctly. Here's a trick that works on a ferro-resonant charger, which is the kind you should be using, as they are dumb. If you can plug the charger into a generator output, you can increase the charger's output by running the generator's engine faster and go from 60 hz to about 61 or 62 hz. This will hotrod the charger and make it's output go way up. I used to do this on my boat to speed up the process. Also, as you probably know, ferro-resonant chargers are battery killers. So once you get the batteries partially charged, switch to a smart charger and bring them all the way up. you might even do a conditioning charge and pull them up to 16 volts.

Keep us posted.

 

[Gale Hawkins]

John when the weather gets warm I may try to flush these old junk batteries just to see what comes out. I was just bored with the winter and thought I would try the reversed polarity desulfation idea. :thumbsup:

Personally I think these sponge lead battery plates just wear out after so many years. :laughing:

The fact that the batteries work reversed was interesting. Actually in run down test with headlights they seem to be stronger. There are no "dead" cells out of the 24 and SG testing will show cells anywhere from fully charged to 50% charged. Each of the four batteries will have at least one cell fully charged and none less than 50% charged to be more specific. Each one will pass on a 10 second 100 amp load test.

i will play with them for a while longer then reverse the polarity back again to as marked on the battery before I try anything else with them in the future.