Solar Battery Question : LUSENET : TimeBomb 2000 (Y2000) Preparation Forum : One Thread

I bought a decent sized solar array. Do the batteries have to be drained to any degree, on a regular basis, or can they stay in a state of full charge, because of non use?

Thanks in advance for any info.


-- Muke (, January 02, 2000


By the way, the batteries are Trojan L-16's.


-- Mike (, January 02, 2000.

Lead-acid batteries enjoy sitting at full charge. They're not like Nicads in that regard.

If you have a charge controller, it should keep them in good shape. If you don't, I'd suggest getting a "float charger" (I bought a bunch of "Chicago Electric" (made in china, of course) from some people on eBay. There are a bunch of people who keep listing them, so if you're looking for one, don't grab the first that comes along unless it's at a decent price.

A float charger isn't designed to charge the battery, but to *maintain* a charge.

I also bought an Exide "trolling battery" charger after reading a bunch of Hams say how great they are. (They use them to maintain batteries for their portables and repeaters.) It's a slick little item. It varies its charge rate depending on the degree of discharge, and then gives periodic little "blips" when it senses that the battery has self-discharged a little. (You can watch what it's doing by monitoring two LEDs.)

I think you can pick an Exide up at a place like Quality Farm and Fleet. I bought mine used "for cheap" from eBay, but if I had the bucks, I'd run to Quality Farm and buy a few more. It's only ten amps or so, but it's *extremely* considerate of your batteries.

-- Ron Schwarz (, January 03, 2000.

You do NOT want to leave lead-acid batteries discharged, or think you have to cycle them. They do not have "memory" problems like Ni-Cad.

Keep a float charger on them at all times and they'll be good for years to come.

-- Gary S. (, January 03, 2000.

Hi Mike,

For what its worth, I think you've put the cart before the horse. If it is a decent sized system, then you INVESTED serious money in it. Do yourself a favor and learn about its 'care and feeding' (or work up a regular maintenance schedule with the installer and have him come in to handle it.)

Little things that can make a big difference - like wrapping all but the working areas of your tools with electrical tape (you don't want an uninsulated wrench or screwdriver to fall across the terminals of one of those batteries) And be sure you have enough baking soda in onsite drums to neutralize the acid in those batteries. Photovoltaics are serious enengy options (or toys that command great respect.) Let me know if you get bored with your system. Maybe we could work something out.


-- john hebert (, January 03, 2000.


Rather than just let everything sit, why don't you use your stored power periodically? Don't drag the batteries down, maybe discharge to only 80 or 90% of capacity.

Or, you might find that you can run a good bit of your house from the system and cut back on electricity bills.

As you do this you'll learn. You'll think of questions, and probably find answers. As you learn you'll be able to maintain your system.

-- (4@5.6), January 04, 2000.

Mike, If you have a "decent sized solar array" I would hope that you have a good charge controller with it. Are your solar panels installed and set up to charge the batteries? If they are, a good charge controller should be able to keep them "trickle" charged (at float voltage) with no problem. The best thing to do, in my opinion, would be to have them set up, charging the batteries through a good charge controller, and use some of this electricity to power part of you house,shop,etc., which will help you get used to an alternative power system, and keep your equipment, including batteries, in good shape, ready to take over your loads in a power outage. We have a "Trimetric" battery monitor that helps keep track of the condition of the batteries, and I find that it is very helpful in letting me know what condition they are in, how much power I am getting from the sun adn wind, how much I use, etc. I would recommend some kind of battery monitor like that in addition to agood charge controller.


-- Jim (, January 04, 2000.

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