Deep Cycle Battery Rejuvenation

Good Links, thanks Aurizon.

I agree, nothing that you add to a battery (except maybe distilled water) can ever help.

I have one of those electronic activators on my leisure caravan battery, which must be around 9 years old now (the activator itself is only 4 years old!).....I have the impression that it helps, but no proper testing has been made. I think at least it does no harm.......which is hardly a recommendation, sorry!

But I will continue to use it until I see a negative effect......

My personal take on keeping a battery fit for a long life is that NOT using a full charge ever (not over say 13.4 volts only about 70% full) and not using a full discharge (not under 12.6 volts, except for short periods maybe, though leisure batteries handle that much better than other types), seems to keep batteries very healthy in my opinion/experience.

The charge up and drop down and charge up also appear to keep a battery "fitter" than chargers which trickle charge between charges......also not tested in a proper manner, only an opinion though....almost like PT for batteries....

If a trickle charge is used, you must set it so that either the battery just "holds" its charge (each battery is different by the way!!) or the charge is very slightly lost over a long period.....the trickle must never actually increase the charge on the battery......putting a smaller battery in place of a larger one for example will usually result in the need for readjustment of the trickle......

But I really don't like trickle charging - ever.

I have tried adding Magnesium Sulphate to batteries, also Cadmium Sulphate. Also I have used a discharger that pumps heavy electrical spikes into the battery.

NONE of these ideas worked.

Just keep monitoring the batteries, check specific gravity of the acid, check voltage, and keep top of batteries clean.

Replace ALL batteries when one or two are obviously past it. If you replace each battery as it fails, you will be wasting a lot of time with each replacement. Better to do it all in one hit.

Start saving for the big day.

I was doing research on this a while ago & came across some 1 on a web site saying that the life of a battery can be greatly extended by using a chemical & also restore a battery sulphated almost to the point of no use back to 90% of new capacity useing the pulse recovery charging system & this chemical added to the battery

The chemical is called Ethylene Diamine Tetra Acetic Acid or EDTA for abreviated term

apparently is causes the coating of sulphate to seperate from the lead & fall to the bottom of the cell where it can be either washed out or left there as having an insulating quality it will not cause problems

I offer the disclaimer that I have not tested this process, & have not been able to obtain this chemical to test it & therefore have no idea if it even works & would advise any 1 that wishes to try this on a battery to do so on an old 1 to test the efectivness I have merely found this information somewhere on the internet but have since lost the address to the page

I Australia we use a 'square wave pulser' (can supply details if necessary) and some people swear by the results. I have not tried myself. Penttijp Brisbane Qld.

Do you on occasion give your batteries a saturation charge? Sulfation will occur on these types of batteries. The battery manufacturer suggests doing this to get the most out of your batteries. I did an extensive study of off grid solar/storage systems. If you've had 5 years of good service I'd say you're doing better than most. I also wouldn't put the additive you mentioned. All the literature I've read calls out for distilled or ionized water, NO acid. If your additive is an acid based product I'd be really careful.

I am not sure about batteries but elemental sulfur causes no end of problems in water wells and in sour gas wells in the petroleum industry. I was involved in water wells and we were always limited what we could do to chemically clean a water well, for obvious reasons. I can tell you that the solubility of elemental sulfur is weak in alcohol and most other allowable chemicals. We would usually resort to mechanical cleaning with a drill rig and pressure washing followed by flushing. It was always frustrating to find a well clogged with elemental sulfur and you knew the cure would be very expensive. I was always interested in prevention but was not very successful.

In the petroleum industry a chemical like liquid carbon disulfide (CS2) has had some good results removing elemental sulfur. I am not sure how you would apply CS2 to cleaning solid sulfur from the plates in a battery but it seems possible. I suspect bathing them in a heated solution but CS2 may be too dangerous for bench top work. I would suggest you contact some suppliers of CS2 and put it past them for information on this specific use and handling. CS2 is reported to have had good levels of success in the oil industry. Sorry I can not relate any of my experiences to CS2 uses in water wells and then extrapolate that information to cleaning batteries, a bit of a stretch perhaps.

GA and thanks for the info. Well stated.

Kev

I'm not an EE by any stretch of the imagination, but I have found a product that'll help rejuvenate your lead-acid batteries. I've been using this product the past 10 months and it does exactly what the company advertises it would do to old batteries.

Check out this newer high tech company called BatteryMinder from New Jersey. Be forewarned that their products are usually back-ordered a few weeks to a month! That how much in demand their units are!!! Their units have been touted as state-of-the-art and best on the market.

I own a BatteryMinder Model #12248 - Charger-Maintainer-Desulphator-Conditioners. the price is now around $136 USD. This model is for 12 VDC batteries. They do manufacturer a unit that services 6 VDC cells. Note: these units will help restore the charge on fully depleted, damaged or leaking batteries. Also, follow the lengthy manufacturer's written instructions to the letter, or else you're wasting you time, $$$$ and efforts.

Good luck!

There are many similar working units with regard to the desulfation process. Some only cost $25, I have such a unit, it appears to work OK.

A regulated charger, that can be adjusted not to overcharge can be bought for a similar amount of money.

In our younger days when cash was low and battery was near dead we would drain the battery acid into a suitable container then add half that amount of hot clean water to the battery and slosh it about for a while and dump it out then replace the acid after usually filtering it through a milk filter to remove and suspended particles. Place it on charge and most of the time you got another kick at the cat for a while.. It did not make it like new but at least it could function enough to get your wheels moving.

You explain well what is basically a "normal" procedure for large expensive batteries, well done and many thanks for the reminder......we were taught such a procedure in the RN.

My only modification (and maybe not a complete explanation!) is to say that the battery should be charged first, the hot water must be distilled hot water and the acid needs to be corrected in strength for a full charge using a Hydrometer and the temperature correction chart......maybe then it would have held longer!!

Its usually the debris on the bottom of each cell that shorts out the plates.....remove that and it may spring into life!!

Hi Andy sounds like similar background.. On the farm we did not have the tools or some materials. No distilled water, no hydrometer, oh yes we had rain water. I even watched my father take a battery apart and take a cell from another battery and insert it in the failed battery and get it working (for a while). Then he would heat the tar that was the seal and re pour it back. Of course in those days most of our equipment was 6 Volt. I think he used a small light bulb for a voltage tester to check the cell or to locate the dead cell. It was an interesting life to say the least for a very young lad.

That is probably the best way to learn in the world, watching and getting your hands dirty with "real hands-on".......

I bet you have never forgotten "how" either!!!

Have a good one......

Exactly, but it will have reduced capacity, because in deep cycled batteries the lead peroxide paste in the positive plates is permeated with sulphate, becomes brittle, and during gassing gets loose and collects at the bottom of the cell. A "new" discharged cell can be completely reconditioned by use of some of the methods above, or lengthy slow charging. Once the active material is out of the positive plates, it's impossible to restore capacity. Total replacement is required, and as said earlier: All the cells!

I am happy still with the capacity of my 9 year old trailer battery, but it is a really good make.......it appears to be as good as new.....! No cell shorts.....yet! And only water added and my special DIY charger!!

What is the expected average life of a 120 AH leisure battery? Any idea?

According to this your 9 year life is outstanding, unless you are using industrial forklift batteries.

Most deep cycle batteries are rated on number of charge/discharge cycles, and it depends on the depth of discharge and how close to fully charged you bring your batteries on recharging. Based on your experiences described elsewhere (especially limiting the recharge to about 80% of full capacity, and avoiding trickle charging) suggests that some of the "common wisdom" within the battery community might be erroneous...

I, personally, have never met a battery that can be expected to give full performance for more than 4 or 5 years- and those are the more costly ones...But, then, I have had very little control over most of the batteries I have met...

We had remote radio stations around the SA coast. Charge of one set of batteries was started on low voltage, after the other set was put into use . We also reduced the charge top voltage from 2.6 per cell to 2.25 to extend life and prevent too much gassing. The charge duration (~12 hours) was not changed. Once in two months we did an equalizing charge. The change in life was amazing.

Firstly GA.

Many thanks for your comments.

Sounds like that battery is on borrowed time.......but as I can replace it fairly easily anywhere, I will keep using it till it collapses....

9 years. Good going. I have a Jap car. replaced the battery in 2002. 2011, still fine.

Home alarm: sealed lead acid, 7 years old.

Glass cased 400Ah cells lasted >20 years in Industrial use at my previous employer.

Guess us oldies could fill a set of encyclopedias on the subject. Don't use Epsom Salt in the battery unless you want to sell the car in a hurry. If the diff is noisy, use banana peels or stuff it with nylon panty hose, etc.

Also did that. It gets rid of the disintegrated positive plate matter that has fallen to the bottom and caused short circuits between the plates. Doesn't restore capacity, but as you say, gets your wheels moving.

I've had good success using the desulfator from www.batteryminders.com I've used the product on standard 12V lead acid, lead acid maintainance free, and gell cell batteries. I used the Battery Minder on a 12v battery that had a charge of -50% and it came back up to 100% charge. It is a slow process but it has worked for me. I left my severely discharged battery on the desulfator for 3 weeks. The company makes a 120V AC model and a solar powered model.

On my PV solar system battery system, there is a built-in desulfator charger.

Good luck.

Don

Very good product.

I got results with positive and negative plates back to normal, also in about three weeks of charge, using a similar method. It doesn't happen "overnight". Don't make the cells gas, until the plates are brown and gray, when only minute bubbling happens.

It doesn't recondition cells short-circuited by piles of positive material, or "treeing" between plates. If the battery was in good condition and just left to stand and discharge over a long period, try this!

Specially mobile holiday home use...