Restoring or Recharging Dead Batteries

[Love MACs]

Thanks Dave for getting back to me What you said was kinda what I expected but wanted to hear from someone who really knew

Allan

[DaveB]

I just love it when someone disagrees and in this case 2. Point is most persons have older batteries or just got under the 12.3 volt discharge of 50% and may be sulfated, recomended by me is to use acid to replace fluid, also if on is loseing water thru overcharge .
I won't get into how a battery can sulfate or chargeing types for diffrent types of batteries because it is so involved for Types used.
I only gave a small general discription and way to keep most wet cell batteries up for long life. I didn't mention under charge wet cells wet batteries and recharge.
Many manifactures recommend acid replacement without going into a whole lot of detail.
Most times one only uses distilled water and that is way to go unless you sulfated the batteries or boiled over or even lose water evaparation over time, those are the time to fill with battery acid.
I always top my deep cell batteries with 50%acid and 50%distilled no problems with 95% charge in 2 years. Also use it on Golf batteries in series and the 3 Ezgoes Golf carts I manage on 36 volt systems were I work as Trades Worker.
It's all about info and I have plenty of knowledge on Solar, Batteries Types, Wind Generating Systems and now getting involved with Water generating that has improved greatly past 25 years.
Dave







Dave

Dave - I respectfully dissagree. Never add acid to a battery unless you spill some out. Add only distilled water to replace that lost through evaporation, otherwise you will be changing the design concentration of the electrolyte.

Hamin'X- you're correct on both counts! The concrete one is a real "beauty"!

c130king- leaving a battery sit like that is a classic battery killer. But you have some things going for you. A deep cycle battery has thicker, less spongy lead plates (the +ve ones) than a starting battery so they are hardier at handling discharging, which is good. You disconnected the terminals which will prevent parasitic drain (some diodes in place to prevent this will still "leak"current) , so your discharge rate is restricted to only the internal discharge of the battery (might be up to 10% range) high if hotter, humidity will not have much role. And you charged it before you left it, good.

An idle battery should be trickle charged after checking the electrolyte level to be above the plates (inter alios to prevent explosion), and the same in all cells. Contrary to what you might think, top the acid level the rest of the way up after it's fully charged, not before. Note that even a new battery will not reach its rated capacity until a few dozen charge/discharge cycles anyway. The charge rate should be enough to cause bubbling in the cells so there is vertical mixing and no stratification of acid density, (unless the wave action is helping that).

You can tell whether or not to buy a charger by lifting it. If it's heavy don't buy it. It means it has a big clunker of a transformer in it, and relies on the charge current being raised and lowered as the internal resistance of the battery "pushes back". The harder the charger tries to amp the power to it the harder the battery pushes back, and as the battery voltage goes up, the amperage goes down. That's not really "automatic" and it's not the best thing for the long-term health of the battery. At least you do not want to leave these connected to your battery for any length of time.

The good ones are lighter, solid state, fan cooled, and will automatically feed exactly the amount of amperage that the battery can easily take. They will then switch over to a maintenance mode that will trickle current only when it senses the voltage drop in the battery. Might be under $100 for a good one in the USA.

next post>>>

[seahouse]

Hey Dave --

Of course we're talking about 12 volt deep-cycle lead acid wet-cell batteries here. Which manufacturer recommends battery top-up with something other than distilled water? Any reference? I've never heard of that, (but that doesn't mean it hasn't happened) so I'd like to know more about it.

Doing that would cause in increase over time, (and not a consistent one) in the acid concentration in the battery, replacing lost water with acid.

It would also render specific gravity readings with a hygrometer useless, and specific gravity is the best way to determine state of charge, as voltage readings are only approximations. A baseline specific gravity reading done when the battery is new (as proper maintenance procedure dictates) would then be irrelevant.

If a person is losing water from overcharge, I can think of a better solution to that problem than adding acid to the battery.

BTW - a voltage reading of 12.3 volts indicates a charge state of closer to 70% than 50%.

There are differences in acid concentration that depend on the latitude of the selling store, higher concentrations in cold latitudes, and lower concentrations in warm ones, but the differences are slight.

Hey Jim -- I didn't specify my own charger model because it is a house brand of a Canadian chain store, only available here, and I don't know which manufacturer makes it for them. I'll end this post and post later after I have a look online. But they are usually referred to as "intelligent" or "smart" or with "optimal charge logic". It is for "in garage" use for me too. I use it for forklift, motorcycle, sea-doo, 6V deep cycle solar/wind bank, but rarely for auto batteries, except for friends. I don't have a Mac (and batteries) yet, my neighbour with whom we sail weekends just bought a 2009 34' Beneteau loaded, radar, etc, so it'll be another year now before I buy! (or maybe a WingZ 33C) ?

Regards all- Brian.

[seahouse]

Hey Jim--

This is the model (or close) that I have. Nothing magical about this particular one - I think most of this type along this line should serve you well.

http://www.canadiantire.ca/browse/produ ... 3719337251

Yipes - tried to delete this one - no luck! Help moderator!

[seahouse]

Hey Jim--

This is the model (or close) that I have. Nothing magical about this particular one - I think most of this type along this line should serve you well. But it is on sale now!

http://www.canadiantire.ca/browse/produ ... 3719337251

Regards - Brian.

[Hamin' X]

I just love it when someone disagrees and in this case 2.

Yes, I do disagree. I too have some expertise with batteries and contacts with battery manufactures, maintaining and installing emergency power and solar power for communication sites. I just replaced a set of batteries last fall with an in service date of 1986. I will let one manufacture speak for themselves:

Do you ever add acid to a battery? Under normal operating conditions, you never need to add acid. Only distilled, deionized or approved water should be added to achieve the recommended levels mentioned above. When a battery is shipped in a dry state or accidental spillage occurs, electrolyte should be added to the battery. Once filled, a battery should only need periodic water addition.

Source

IMHO, if you need to add acid, you are treating a symptom of a disease. Deeper problems are there, such as: Overcharging, resulting in boiling over and lost electrolyte, or unsecured batteries, resulting in spilled electrolyte, or overfilling the battery. One common mistake is to fill the battery prior to charging. When the battery is charged, it results in heat and the loss of electrolyte, due to expansion.

If there is better information than this, I am open to further discussion.

~Rich

[c130king]

Brian,

Thanks again. I will look for something like that when I get back.

Cheers,
Jim
Sailing on König

[waternwaves]

if you boil out a cell and smell sulfur..........then you have to add elctrolyte......

I have a small 12 V sealed wet cell I just revieved that powered a buddies UPS..... HE boiled that puppy dry...we'll see how the desulfating works on that unit. no starting sg........since there was no liquid present. smart charger says battery is toast.. we'll see.

already recovered 4 of 6 cells hmmmmmmmm

[ronacarme]

Original stock 26D battery in boat in MI, trickle charged year around by a 5 watt solar plate, stayed like new for as long as I had the boat (1988-2000). Moderate battery use in summer season, ie rare running light use, occaisional VHF and CD player and cabin light use.

Original stock 2001 26X battery, similarly treated (except with 9.9 hp motor with alternator and electric start), still like new.

The 5 watt plate has really paid for itself.

Ron

[seahouse]

Hey Jim --

This link might help if you're shopping for a "switchmode" charger...

http://home.iprimus.com.au/rfh/battchargers.html

Some good info here.

Regards - Brian.

[c130king]

Brian,

Very good info on chargers. Thanks for posting that.

Cheers,
Jim
Sailing on König