"This memory effect thing is mostly an urban myth. Memory only affects one very specific kind of battery: sintered-plate nickel-cadmium designs. Pocket-plate nickel-cadmium batteries are free of the effect, as-well-as, all nickel metal-hydride (NiMh) designs."
Din ce stiu ciclii de incarcare descarcare, mai ales la acumulatorii inteligenti cu battery gauge, sunt pentru alt motiv, nu pentru efectul de memorie: in timp capacitatea utila a acumulatorilor scade si battery gauge trebuie recalibrat. Vezi de exemplu calibrarea periodica recomandata de APC la bateriile de UPS, chiar daca au alta tehnologie de inmagazinare tot au nevoie de un ciclu de descarcare pentru calibrare.
Do NiCd batteries really have a memory effect?
Answering this question is a sure way to start a flame war on the internet. The simple answer is: Technically speaking NiCd batteries do not have a memory effect. However, they do suffer from a voltage depletion or voltage depression phenomenon that most people call the memory effect. So practically speaking, NiCd batteries do suffer from a memory effect, even if it is not technically correct to call it that. There is a lot of disagreement in the battery industry over what actually causes voltage depression. The phenomenon itself is very real. If a NiCd battery is repeatedly charged after it has only been partially discharged it will develop a lower voltage and a lower capacity. Fortunately, this effect is reversible by conditioning NiCds. Conditioning is simply fully discharging the battery (down to about 1.0 V per cell) after charging it. If a full discharge followed by a charge cycle is done several times, a battery suffering from voltage depletion (voltage depression, memory effect, or whatever you would like to call it) should be restored back to its normal voltage and capacity.
If you use NiCd batteries you should be aware that most of the problems experienced by NiCd battery users are not due to a "memory effect" but are due to overcharging or improper storage. Overcharging is usually caused by poorly designed first generation battery chargers. These chargers continue to deliver current to the batteries even after the batteries are full charged. "5- hour" and "8-hour" timer type chargers can damage NiCd or NiMH batteries if they are frequently used to charge batteries that are only partially discharged.
The other common cause of damage to NiCd and NiMH batteries is leaving them in a device like a flashlight left "ON" after the battery has run down. Electronic devices normally switch themselves off once the battery is discharged. But other devices like flashlights, cassette players, and many toys, will continue to put a small load (drain) on a battery even after the battery is run down. Eventually (after a few weeks) this drain on a discharged battery will cause the polarity of the battery to reverse (the plus end actually becomes minus and vice versa). Once this happens the battery will not take a charge again. Battery makers recommend that rechargeable batteries be removed from any devices that will not be used for several weeks or longer.
The big difference between voltage depletion, the so called "memory effect" and damage caused by overcharging or improper storage, is that reduced capacity due to overcharging is not reversible.
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Do NiMH batteries have memory effect?
Technically, NiMH batteries do not have a "memory effect", but strictly speaking neither do NiCds. However NiMH batteries can experience voltage depletion, also called voltage depression, similar to that of NiCd batteries, but the effect is normally less noticeable. To completely eliminate the possibility of NiMH batteries suffering any voltage depletion effect manufacturers recommend an OCCASIONAL, complete discharge of NiMH batteries followed by a full recharge. NiMH batteries can also be damaged by overcharge and improper storage (see the NiCd section immediately above this one). Most users of NiMH batteries don't have to be concerned with this voltage depletion effect. But if you use a device say a flashlight, radio, or digital camera for only a short time every day and then charge the batteries every night, you will need to let the NiMH (or NiCd) batteries run down occasionally.
M-am uitat de 3 ori pe baterii, scrie ALKALINE MN1500, 1.5V LR6 - Duracell. Aveam cardul de memorie destul de gol (doar vreo 3 poze), asa ca atunci cand se termina bateriile, o sa vad exact cate poze pot face cu un set.Difera tensiunile inclusiv intre cele pe Zn si cele alkaline. Tot ce e foto cu baterii AA e calibrat pt. alkaline. Daca bagi "Super-ultra GP power supreme subspace energy grabber" dar nu scrie pe ea ca e alkalina, o sa-ti arate aiurea.