How many years can you get away with storing lead acid batteries?

I have a UPS which I replaced the batteries in 2003 and the battery is still as good as new when I ran a runtime test the other day. The UPS is not being used, however it is plugged in every few months for a night, then the battery is disconnected.


Can you store lead acid batteries almost indefinitely as long as you perform a proper top off charge? If you leave the trickle on, it will degrade from heat and corrosion. If you don't do anything at all, it will sulfate.

I recently changed over an industrial lead acid back up battery on a radio transmission site,
the batteries were 12 years old and still quite able to hold a charge and deliver the required current.

Handlobraesing said:

I have a UPS which I replaced the batteries in 2003 and the battery is still as good as new when I ran a runtime test the other day. The UPS is not being used, however it is plugged in every few months for a night, then the battery is disconnected.


Can you store lead acid batteries almost indefinitely as long as you perform a proper top off charge? If you leave the trickle on, it will degrade from heat and corrosion. If you don't do anything at all, it will sulfate.

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I have a Elec-trak e20 Electric tractor built around 1974. The previous owner charged the 6-200 amp hour lead acid batteries just once a month when it was not being used. The batteries were in near perfect condition after 30 years of once a month charging. They would power the tractor up steep hills for many miles.

After 31 years of use I dropped a wrench across the terminals right after they were done charging and 2 of the 6 exploded 12 inches from my head my ears were ringing for 2 days. The tops blew off the batteries and sounded like a Big M80. After I replaced all 6 batteries I could not tell any difference in amp draw or range compared to the old ones.


I've found the best way to store Lead acid is with a float charger set at about 13.2 volts. Also try to keep lead acid's in a more stable temperature. Leaving them under the hood of a hot car where they can go from -0 to 200+ degrees frequently won't help them last for many years. Don't use a trickle charger unless it has a float charger mode. I own about 4,000 pounds of lead acid's for my electric golf carts, tractors and motor home.

This is the cheapest way to float charge them. This charger only put's out about 500mahs so it could take 200 hours to charge a large car battery but it works great to keep them charged forever at 13.2 volts $6.99 http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=42292


This one will trickle at 1.5 amps and automatically float charge. I have 350 pounds of batteries hooked to one of these and year around they stay at 13.2 volts. $12.99 http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=93258

The big batteries used in industrial applications last for decades. When I worked for the phone company every equipment building had a section dedicated to batteries. The phone system runs on these batteries. They are under constant charge at the proper voltage. There's no need for a UPS in most cases. When the power goes out the equipment is already running from the batteries.

Temperature control, float charging and keeping the electrolyte at the right concentration / level are the keys.

Daniel