Winter Care Of Batteries At Home

[Mark Yashinsky]

after lugging them out and home??? Want a proper double blind test and the final results written, using all the technical jargon. Someone want to surf and find any RECENT articles from reputable (battery companies???) sources.

[Larry DeMers]

I Love those guys! We awaken Saturday mornings and at 9am, the FM is on NPR for Click and Clack...and my dose of wake-me-up humor with some intelligence behind it. By the time "What Do You Know" comes on, we are usually under sail and on the way to that days destination. It is a nice little routine that we kind of slid into long ago, and now it turns out to be something that I repeat purposefully during our long winter up here, to kind of stay in the boating frame of mind.

I suspect that the source of the battery discharges while on garage floor story was something like what they allude to. Add in an earthen floor, a wood case, and leaks of electrolyte, and there would be battery discharge problems.

Thanks,

Larry DeMers
s/v DeLaMer
CD30 On Lake Superior

Click and Clack on NPR say that this is not necessary. Apparently in the early days of batteries the case was made of wood or metal which would allow them to discharge via the case to the ground. Since modern battery cases are made of rubber or plastic they provide insulation. Many people still do it, however, just like you see old timers driving around with their headlights on so the battery won't overcharge. Seems this was necessary in the days before voltage regulators. I'm not a PhD, I'm just real old.

The only other advice that I've heard is that batteries should not be stored on a concrete floor, but should be put on wood boards. I don't know why. Ask a PhD if you want to know!

Darin

I know there was just a very large discussion of batteries on the PhD level and my knowledge of batteries might get me out of grammar school. I know some of you out there could use your on board power to light up a small city for a week. For me, 99% of my power goes to starting the engine and powering the knotmeter and depthfinder. Now and then a bilge pump and the VHF. Hardly ever a cabin light.
So, my intricate battery set up is composed of two DieHard marine batteries. Last year, the yard pulled my batteries and took care of them for the winter to the tune of 120 smackers. I have no complaints about what they did but the 120 bucks could be better used. I'd like to take the batteries home and take care of them myself. I have an automotive battery charger with both 2 and 6 amp settings. I know what everyone has been saying about automotive chargers but I figure that was more about standard recharging during the season. What I got out of the "PhD level" discussion is that I could put a voltmeter on my batteries during the winter and most likely about once a month I could put the charger on them, at the trickle charge 2 amp setting, and keep them in good shape over the winter. There wouldn't be any load on them so I guess you could call it a "maintenance charge". Any suggestions would be welcome. I would have no problem in going out and buying a marine type charger, but is it necessary for this type of winter charging only?

Thanks,
Warren Kaplan
S/V Sine Qua Non
CD27 #166 (1980)

demers@sgi.com

[Ken Coit]

So, I found a site that claims that the batteries can be damaged by storing them on a concrete floor is an urban legend and then goes on to say:

"10.1. Storing a battery on a concrete floor will discharge them.

A hundred years ago when battery cases were made of porous materials, such as wood, storing batteries on concrete floors would accelerate their discharge. Modern battery cases, made of polypropylene or hard rubber, which are better sealed, so external leakage, causing discharge, is no longer a problem. However, the top of the battery must be clean and dry. [Temperature stratification within large batteries could accelerate the internal "leakage" or self-discharge if the battery is sitting on a cold floor in a warm room or is installed in a submarine.]"

Please note the "technical" information in brackets. I think Rolls may have something on this as well, but I'm not going to take the time to search it out at the moment.

Ken

You may be very correct here. Though I seem to remember that the story about keeping the batteries off the floor was because it killed the battery?
A battery brought to a lower temp by a cold cement floor will loose a few hundred millivolts or maybe half a volt max. over time, due to the spg concentration changing due to temps. That does not constitute a discharged battery though, so I suspect that there was more to the story. Possibly it had to do with the battery case materials, battery efficiency, and damp floors..not of cement but earth (a far better conductor) combined. Even then, I have a hard time imagining this discharge path actually working.
Wouldn't it be ironic if this whole story is another urban legend that has gone on for 30 years or more? heh..

Larry

Just my two cents to this conversation. Batteries that are placed on concrete floors APPEAR to have a faster discharge rate, though they do not discharge any faster than a battery on piece of wood or other insulation. The direct contact to the COLDER concrete floor is the cause and simply shows more discharge because of the colder temp of the battery (harmless). So it doesn't matter if their stored on the ground, but they do need to be kept charged for ultimate long life of the battery.

Ok, cement may be full of salts and moisture..although "full of" is too strong a word here, me thinks. Now for the part that your message does not talk about..the battery case itself. Battery cases are *insolators*, not conductors of electricity, otherwise the battery wouldn't hold a charge, right? How then does the current flow from the negative post down to the concrete floor, through the 'salts and moisture' of the concrete floor, back up the battery case to the positive post?

The only way would be if the case itself were conductive. To be conductive, the case would have to be covered in dried battery acid, dried saltwater continuously up the sides, or contaminated in some other way.

A clean and well cared for battery will not increase it's own self discharge rate when stored on a cement floor. There is no path for the current to follow.

Now put that battery on cement and then over charge the darn thing for a couple weeks before disconnecting it from the charging source, and the case will have electrolyte evaporated all over the battery..and will conduct probably.

So that scenario would be what you are talking about I suppose. So the warning then should be to clean that battery case well before storing it away, and the discharge path will be interrupted, preventing the whole problem.

Cheers,

Larry DeMers
s/v DeLaMer
Cape Dory 30 Lake Superior

parfait@nc.rr.com

[D. Stump, Hanalei]

Captain Cawthorne,

Don't know what tide this drifted in on, but I do NOT store my batteries, clean or dirty, on the concrete floor! I puts them on plastic milk carton holders(shippin' containers?) turned upside down. This seems to keep the gremlins from dischargin' the foolish thin's. For scientific substantion of this theory, meet me and my crew at the Bow and Thistle Tavern, port of Noank, for a glass of hot grog on a snowy evening this winter to come...I remain Sir......your most HUMBLE and CHARGED UP servant......

David Stump
Captain Commanding
s/v Hanalei CD-30C
CDSOA #1

On the hard and on half-pay this weekend after next...

[D. Stump, Hanalei]

Captain Yar(short for Yashinsky),

Batteries be simple thin's, a little lead, a little plastic, some really burney stuff and viola, ya get char'ed. Instead of wastin' all this time, I suggest we all meet at the Bow & Thistle Tavern this winter on a cold and snowy evenin' and talk over all this important stuff! In the meantime, DO NOT store your batteries on concrete for (whatever reason)! I remain Sir, your most "tongue in cheek"...HUMBLE servant......

Dave Stump
Captain Commanding
s/v Hanalei

[nigelnoble]

Do you recommend the same maintenance schedule for AGM batteries over the winter?

[Joe CD MS 300]

Has anyone used these small battery maintaners that look like the low power wall transformers??? Suppose to clip them on and ("computer chip") it will maintain and cycle the battery over a long period. Not meant for recharging, just keeping the battery health and topped up when the battery is not used for a long period.

Battery tender is a name brand that is sold in motorcycle shops all over. Motorcycles get used a lot like boats, intermittently and little at all during the winter. My ridding buddy still has his original 8 year old battery. The tenders wont charge a dead battery but do keep a charged battery topped off. You can get a similar tender at Harbor freight often for as little as $4. No need to use a timer which probably uses more juice than the tender just keep it hooked up all winter long,

[M. R. Bober]

Unless I have misunderstood many things--including a serious discussion with a technical representative of the Rolls Battery Company--the discharge rate of an unused battery slows as the temperature drops. I seem to recall some rule from Chemistry 101, that loosely states that the reaction time halves for each 10 degree C temperature drop. So a battery stored on a nice cool concrete garage floor should retain more of its charge, over time, than the same battery stored--with you--under the covers in your bedroom.

Personal opinion: Batteries are dumb, really not very smart, and don't know if they are sitting on concrete or Miss America's lap. How different from most of us. If you need a reason to place wooden blocks under your battery, here's one: if the battery does not have built-in handles, being able to get your hands under it makes it easier to lift.

As for me, I charge the batteries fully as a part of winterization, and leave them on the boat. Like Matt, I run the charger when I "visit" during the lay-up. For the record, I use Trojan flooded deep cycle (Group 31) and have gotten many years of good service from them.

Mitchell Bober
Sunny Lancaster (where we may be poles apart, but currently are in a meditative state with our mantra, "Ohmmmmmmm.) VA