Sealed Lead Batteries: do they suffer from "memory effect"?

Lead acid batteries do not have a memory problem. They have other types.

Never let them become fully discharged for too long. They can be damaged in a discharged state. They have a lifespan of about 3 to 5 years maximum.

If the batteries are defective in most UPS's, the UPS may not want to start properly. When the batteries are going bad, there will usually be some type of battery alarm on the UPS, if it has the option.

It is best to replace the batteries with the proper replacements when due. This will allow for the best efficiency for perforance from the UPS, and its internal charger.

Jerry G. ______

Yes what Jerry said. The best way to look after a Lead Acid cell is to keep it on charge BUT at the correct float or continious charge voltage. For a wet cell this is usually slightly below the fully charged voltage but not by much. The voltage is slightly reduced to prevent the cell "boiling" dry. Never leave a lead acid cell discharged as thats the fastest way to kill them.

I have a deep discharge wet lead acid battery that's been hooked up to a float charger for 5 years. It's only taken off float charge when it needs to be used or the acid level checked. Still works ok.