Glossary definition of Memory Effect

Memory Effect is the property of a battery that occurs when it is repeatedly recharged after only a partial discharge. The battery can lose its capacity to hold a full charge, which may reduce its lifetime, and this effect gives the appearance of the battery developing a memory that it has a lower capacity.

Memory Effect most commonly occurs as a problem with Nickel Cadmium NiCd batteries; it occurs less with NiMH, and Li-Ion batteries are hardly ever affected.