WHAT?IS?THE?“MEMORY?EFFECT”??
Memory?Effect?affects?the?run?time?of?a?traditional?(NiCd)?Nickel?Cadmium?Rechargeable?Battery.?There?is?some?misconception?about?the?word?“memory”.?Memory?is?commonly?blamed?for?just?about?any?battery?failure?known?to?man.?The?word?”memory”?is?derived?from?“cyclic?memory”,?meaning?that?a?NiCd?battery?could?remember?how?much?discharge?was?required?on?previous?discharges?and?then?fail?to?regain?a?full?capacity?recharge.?Improvements?in?battery?technology?have?virtually?eliminated?this?phenomenon.?The?problem?with?the?modern?NiCd?battery?is?not?the?cyclic?memory?but?the?effects?of?large?crystalline?formation.?(When?we?refer?to?memory,?we?are?referring?to?the?formation?of?crystals.)?The?active?materials?(nickel?&?cadmium)?of?a?NiCd?battery?are?present?in?crystalline?form.?When?the?memory?Phenomenon?occurs,?these?crystals?grow,?forming?spike?or?tree-like?crystals?that?cause?the?NiCd?to?gradually?lose?performance?and?shut?off?early?.?In?advanced?stages,?these?crystals?may?puncture?the?separator,?causing?high?self-discharge?or?an?electrical?short.?Crystalline?formation?only?presents?a?problem?if?the?battery?is?repeatedly?recharged?without?a?periodic?full?discharge.?It?is?not?necessary?to?discharge?a?NiCd?before?each?charge.?A?full?discharge?to?one?volt?per?cell?once?a?month?is?sufficient?to?keep?the?crystal?formation?under?control.?Such?a?discharge/charge?cycle?is?commonly?referred?to?as?“exercise”.?

If?no?exercise?is?applied?for?several?months,?the?crystals?engrain?themselves,?making?it?more?difficult?to?dissolve.?In?such?a?case,?exercise?is?no?longer?effective?in?restoring?a?battery?and?“recondition”?is?required.?Recondition?is?a?slow,?deep?discharge?that?drains?the?cell?to?a?voltage?threshold?below?one?volt?must?be?discharged?to?at?least?0.6?volts?per?cell?to?dissolve?the?more?resistive?crystalline?build-up.?If?you?use?NiCd?batteries?you?should?purchase?a?charger?with?a?"conditioning"?function?to?neutralize?the?crystalline?build-up?problem.?

Not?all?NiCd?batteries?respond?well?to?recondition.?A?battery?that?has?been?in?service?for?over?a?year?and?had?not?been?exercised?regularly?may?have?a?capacity?reading?that?dropped?to?a?low?20%.?Even?with?repeated?recondition?cycles,?the?battery?may?not?improve?to?an?acceptable?capacity?

Nimh?Rechargeable?Batteries?have?almost?no?Memory?Effect.?Nimh?have?a?different?internal?chemistry?and?are?not?as?susceptible?to?the?same?“memory”?problems?as?NiCds.?In?fact?Nimh?batteries?can?and?should?be?charged?from?any?discharge?state.?This?is?a?major?advantage?of?Nimh?batteries?over?NiCd.
什么是“記憶效應”？

記憶效應影響了鎘鎳二次電池的放電時間。關于“記憶”一詞，存在一些誤解。“記憶”源自于“循環記憶”，它意味著鎘鎳電池能夠記住先前的放電量，不能再次充電到最大容量。電池技術的提高正逐漸消除這種現象。?現代鎘鎳電池的問題不在于循環記憶，而在于大量結晶結構的影響。（當我們提到記憶效應的時候，我們將會提到結晶結構。）鎘鎳電池里的活性物質鎳和鎘都表現為晶體形式。當記憶效應發生時，晶體會增長，形成刺釘狀或樹狀結晶，這導致了鎳，鎘逐漸失去其原有功能。進一步的反應，這些晶體可能穿過分離器，導致高的自放電或者短路。如果電池在沒有完全周期性放電的情況下就被反復充電，就會導致結晶的形成。對于鎘鎳電池來講，每次充電前的放電是不必要的。每個月每個電芯完全放電到一伏足以保持水晶結構在控制之下。像那樣的充放電循環通常被稱之為“exercise”。如果幾個月都不"exercise"，結晶將會再次集結，并且使之溶解將更加困難。?在那種情況下，"exercise"在重儲和恢復電池方面將不起作用。恢復是一種緩慢的，深度的放電過程，它放電使電芯達到一個電壓極限，一個電芯一定要由一伏的電壓至少放電至0.6伏以下，才能溶散更多的抗性晶體。?如果你使用鎘鎳電池，就應該買一個帶有壓制形成結晶功能的充電器。?并非所有的鎘鎳電池都有一個好的恢復反應。一個用了一年以上且不被經常循環的電池，容量將下降到20%以下。這時即使多次重復恢復循環，電池也不會提高可接受的容量。鎳氫二次電池幾乎不受記憶效應的影響。它的的內部化學結構使之不像鎘鎳電池一樣遭受記憶效應的影響。事實上鎳氫電池在任何放電狀態下都可以進行再充電。這是鎳氫電池優于鎘鎳電池的一個主要的優勢。