“NIMH”對電池意味著什么？

NiMH的意思是“鎳 – 金屬氫化物”。電池發展史總是很有趣的。最成功的奇特電池之一是鎳氫電池。它使(shi)(shi)用與鎳鎘電(dian)池(chi)相同的(de)氫氧化鎳正極(ji)和KOH電(dian)解(jie)質，但它使(shi)(shi)用氫氣代(dai)替負極(ji)中的(de)鎘。它使(shi)(shi)用一個壓力容器來容納氫氣。鎳氫電(dian)池(chi)用于(yu)低軌(gui)道衛星，它在地球的(de)每次通過(guo)時對電(dian)池(chi)進行(xing)充電(dian)和放電(dian)，因(yin)此是可以為一個長壽命的(de)電(dian)池(chi)。

存儲(chu)氫(qing)的另一種(zhong)方(fang)法是稱為金(jin)屬氫(qing)化物的金(jin)屬間(jian)(jian)化合物。一些金(jin)屬在(zai)其原(yuan)子晶格中具有空間(jian)(jian)以容納氫(qing)原(yuan)子。可(ke)以通過電化學方(fang)法誘導氫(qing)進入(ru)和(he)離(li)開金(jin)屬基質。因此，金(jin)屬氫(qing)化物是鎳氫(qing)電池的一個(ge)變體，采用了一種(zhong)新的低壓儲(chu)氫(qing)方(fang)法。不(bu)幸的是，由于金(jin)屬氫(qing)化物在(zai)暴露于KOH時會腐蝕，因此它們(men)的壽命不(bu)如(ru)鎳氫(qing)電池。

鎳氫電池充電的基礎知識

鎳(nie)鎘電(dian)(dian)(dian)池(chi)和(he)鎳(nie)氫電(dian)(dian)(dian)池(chi)是(shi)最(zui)難(nan)準(zhun)確充(chong)(chong)電(dian)(dian)(dian)的電(dian)(dian)(dian)池(chi)之一(yi)。對于鋰離子(zi)和(he)鉛酸電(dian)(dian)(dian)池(chi)，您可以通過設置(zhi)最(zui)大充(chong)(chong)電(dian)(dian)(dian)電(dian)(dian)(dian)壓(ya)來控制過充(chong)(chong)電(dian)(dian)(dian)，而鎳(nie)氫電(dian)(dian)(dian)池(chi)則(ze)沒有(you)“浮充(chong)(chong)電(dian)(dian)(dian)”電(dian)(dian)(dian)壓(ya)。因此，充(chong)(chong)電(dian)(dian)(dian)是(shi)基于迫使電(dian)(dian)(dian)流(liu)通過電(dian)(dian)(dian)池(chi)。這樣做的電(dian)(dian)(dian)壓(ya)不像其他(ta)電(dian)(dian)(dian)池(chi)那樣固(gu)定(ding)在石頭上(shang)。

并聯充電

因為你不能確定每個電池是否具有相同的阻抗，因此即使它們已滿，有些也會比其他單元或包更多。這意味著您需要為并(bing)聯(lian)電池組中的(de)每個串使用單獨(du)的(de)充電電路，或者以某種其他方(fang)式平(ping)衡電流。

鎳氫電(dian)池的(de)庫侖充電(dian)效(xiao)率通(tong)常為(wei)66％，這意(yi)味著您每運行100安(an)培(pei)小時必須在(zai)電(dian)池中(zhong)放置(zhi)150安(an)培(pei)小時。

在鎳氫電(dian)池(chi)(chi)中，指示充(chong)電(dian)結束時，它非常(chang)依(yi)賴于溫度。糟糕的是(shi)，新(xin)型鎳氫電(dian)池(chi)(chi)在循環早期(qi)會出現(xian)曲線上的顛(dian)簸，特別是(shi)在天氣寒冷時。此外(wai)，當充(chong)電(dian)速率超過(guo)C / 10時，鎳氫電(dian)池(chi)(chi)對過(guo)充(chong)電(dian)損(sun)壞很敏感(gan)。由于電(dian)池(chi)(chi)鼓包并不總是(shi)容易看到，因此可能會出現(xian)輕(qing)微(wei)的過(guo)充(chong)電(dian)。

然而，已經開發出現代(dai)算法以(yi)在不(bu)(bu)使用(yong)熱敏(min)電(dian)(dian)(dian)(dian)阻的(de)情(qing)況下實(shi)現精確充(chong)電(dian)(dian)(dian)(dian)。這(zhe)些充(chong)電(dian)(dian)(dian)(dian)器具有(you)檢測完(wan)全(quan)充(chong)電(dian)(dian)(dian)(dian)的(de)特殊測量(liang)技術，通常(chang)涉及某種脈(mo)沖(chong)周期，其中在脈(mo)沖(chong)期間(jian)和脈(mo)沖(chong)之間(jian)測量(liang)電(dian)(dian)(dian)(dian)壓。對(dui)于多(duo)電(dian)(dian)(dian)(dian)池(chi)(chi)組，如果(guo)電(dian)(dian)(dian)(dian)池(chi)(chi)不(bu)(bu)是全(quan)部處于相同的(de)充(chong)電(dian)(dian)(dian)(dian)狀(zhuang)態，并(bing)且如果(guo)它們的(de)容量(liang)不(bu)(bu)平(ping)(ping)衡(heng)，則電(dian)(dian)(dian)(dian)池(chi)(chi)可(ke)能一次填充(chong)一個(ge)，從而使充(chong)電(dian)(dian)(dian)(dian)結束信號變暗。為了平(ping)(ping)衡(heng)電(dian)(dian)(dian)(dian)池(chi)(chi)，可(ke)能需要幾個(ge)電(dian)(dian)(dian)(dian)池(chi)(chi)充(chong)電(dian)(dian)(dian)(dian) – 放電(dian)(dian)(dian)(dian)循環。幸運(yun)的(de)是，鎳(nie)氫電(dian)(dian)(dian)(dian)池(chi)(chi)并(bing)不(bu)(bu)介意在C / 10或更低的(de)溫(wen)度下過度充(chong)電(dian)(dian)(dian)(dian)，這(zhe)使充(chong)電(dian)(dian)(dian)(dian)器能夠在涓流(liu)充(chong)電(dian)(dian)(dian)(dian)期間(jian)平(ping)(ping)衡(heng)電(dian)(dian)(dian)(dian)池(chi)(chi)。

隨著電池(chi)達(da)到(dao)充(chong)電結束，氧氣開始在電極(ji)處(chu)形成(cheng)，并(bing)在催化(hua)劑處(chu)重新結合。這(zhe)種(zhong)新的化(hua)學反應產(chan)生熱(re)量(liang)(liang)，可以用(yong)熱(re)敏電阻(zu)輕松測量(liang)(liang)。這(zhe)是在快速充(chong)電期間檢測充(chong)電結束的最安全(quan)方法。

隔夜充電方法

對鎳(nie)氫電(dian)(dian)池(chi)(chi)充(chong)(chong)電(dian)(dian)最安全的方法(fa)是以(yi)C / 10或以(yi)下(xia)（每(mei)小(xiao)時額定容量的10％）充(chong)(chong)電(dian)(dian)。因此，100 mAH電(dian)(dian)池(chi)(chi)將以(yi)10 mA充(chong)(chong)電(dian)(dian)15小(xiao)時。該方法(fa)不需(xu)要充(chong)(chong)電(dian)(dian)結束傳感器并確(que)保完(wan)全充(chong)(chong)電(dian)(dian)。現代電(dian)(dian)池(chi)(chi)具有氧氣(qi)再循(xun)環催化劑，可防(fang)(fang)止過(guo)(guo)充(chong)(chong)電(dian)(dian)時電(dian)(dian)池(chi)(chi)受損，但如果充(chong)(chong)電(dian)(dian)率超過(guo)(guo)C / 10，則(ze)這種再循(xun)環無法(fa)跟上。完(wan)全充(chong)(chong)電(dian)(dian)所需(xu)的最低電(dian)(dian)壓隨(sui)溫(wen)度而變化 – 在20攝氏(shi)度時每(mei)個(ge)電(dian)(dian)池(chi)(chi)至少為1.41伏。即使(shi)在C / 10下(xia)持(chi)續充(chong)(chong)電(dian)(dian)也不會(hui)導致放氣(qi)，但它會(hui)使(shi)電(dian)(dian)池(chi)(chi)稍(shao)微加熱。為了延長電(dian)(dian)池(chi)(chi)壽(shou)命，最佳做法(fa)是使(shi)用計時器防(fang)(fang)止過(guo)(guo)度充(chong)(chong)電(dian)(dian)持(chi)續13至15小(xiao)時。

更快充電方法

使用計(ji)時(shi)器(qi)可以在(zai)C / 3.33下充電(dian)(dian)(dian)5小時(shi)。這(zhe)(zhe)(zhe)有(you)點冒險，因為電(dian)(dian)(dian)池在(zai)充電(dian)(dian)(dian)前應完全放電(dian)(dian)(dian)。如果在(zai)計(ji)時(shi)器(qi)啟動(dong)時(shi)電(dian)(dian)(dian)池仍(reng)然(ran)具有(you)90％的容量(liang)，則(ze)很有(you)可能(neng)將電(dian)(dian)(dian)池放空(kong)。確(que)保不發生(sheng)這(zhe)(zhe)(zhe)種(zhong)(zhong)情況的一種(zhong)(zhong)方法(fa)是(shi)讓(rang)充電(dian)(dian)(dian)器(qi)自動(dong)將電(dian)(dian)(dian)池放電(dian)(dian)(dian)至每個電(dian)(dian)(dian)池1伏(fu)，然(ran)后打開充電(dian)(dian)(dian)器(qi)5小時(shi)。這(zhe)(zhe)(zhe)種(zhong)(zhong)方法(fa)的優點是(shi)消除任何(he)電(dian)(dian)(dian)池記憶的機會。但C / 10充電(dian)(dian)(dian)器(qi)中使用的微處(chu)理器(qi)板可以很容易地修改以進行放電(dian)(dian)(dian)。將需要功率耗散(san)封裝以在(zai)合理的時(shi)間(jian)量(liang)內從部分充電(dian)(dian)(dian)的電(dian)(dian)(dian)池耗散(san)能(neng)量(liang)。

最快的充電方法

如(ru)果使(shi)用溫(wen)度(du)(du)監控(kong)器，NiMH電池可以(yi)以(yi)高達(da)1C的速率充電（換句話說，電池容量的100％，安(an)培(pei)小時為(wei)(wei)1.5小時），當終止(zhi)溫(wen)度(du)(du)升高時，dT / dt值(zhi)應設(she)置(zhi)為(wei)(wei)每(mei)分(fen)鐘1至2攝氏度(du)(du)。

涓流充電方法

在(zai)待機模式(shi)下(xia)(xia)(xia)，您可(ke)能(neng)需要在(zai)不損壞電(dian)(dian)(dian)池的情況下(xia)(xia)(xia)將鎳(nie)氫(qing)電(dian)(dian)(dian)池充(chong)電(dian)(dian)(dian)。這可(ke)以在(zai)0.03 C和.05 C之間的電(dian)(dian)(dian)流(liu)下(xia)(xia)(xia)安全地完成。所(suo)需的電(dian)(dian)(dian)壓取(qu)決(jue)于溫(wen)度，因此務(wu)必調節(jie)充(chong)電(dian)(dian)(dian)器中的電(dian)(dian)(dian)流(liu)。

dT / dt與-dV / dt

這兩種(zhong)終(zhong)止(zhi)方法適(shi)用于(yu)鎳(nie)鎘(ge)電(dian)池，也適(shi)用于(yu)鎳(nie)氫電(dian)池。dT / dt測量(liang)充電(dian)結(jie)束(shu)時的溫度會上升。電(dian)池充滿電(dian)后(hou)，會開始新(xin)的化學反應，以(yi)吸收不需要(yao)的電(dian)流。在氫氧化鎳(nie)型電(dian)池中(zhong)，這包括產生和重新(xin)組合氧氣(qi)。此過程會加(jia)(jia)熱電(dian)池。溫度上升的突然增加(jia)(jia)可用于(yu)終(zhong)止(zhi)充電(dian)。

氧氣產生/重組(zu)循環的另一個影響是(shi)略微降低電(dian)(dian)池(chi)的電(dian)(dian)壓。如果您可(ke)(ke)以檢測到此(ci)電(dian)(dian)壓下降，則可(ke)(ke)以使用(yong)(yong)此(ci)信號(hao)終(zhong)止(zhi)充電(dian)(dian)。當(dang)然，-dV / dt是(shi)最簡單的，因為它不(bu)需要溫度傳感器(qi)。鎳氫(qing)電(dian)(dian)池(chi)的最佳方法是(shi)dT / dt方法。主要有兩(liang)個原因。使用(yong)(yong)鎳氫(qing)電(dian)(dian)池(chi)時，電(dian)(dian)壓下降較小，并(bing)且比使用(yong)(yong)鎳鎘電(dian)(dian)池(chi)更難檢測。這幾乎總(zong)能(neng)確保(bao)過充電(dian)(dian)，這將(jiang)限制電(dian)(dian)池(chi)故障前的充電(dian)(dian)/放電(dian)(dian)總(zong)循環次(ci)數。其次(ci)，新的鎳氫(qing)電(dian)(dian)池(chi)在充電(dian)(dian)周期的早期會出現假峰值，因此(ci)充電(dian)(dian)器(qi)將(jiang)很(hen)快終(zhong)止(zhi)。

有(you)一些新算法使(shi)(shi)用(yong)(yong)微處理器(qi)控(kong)制來(lai)使(shi)(shi)用(yong)(yong)-dV信號來(lai)檢測充(chong)(chong)(chong)電結束。這些可(ke)以很好地工作(zuo)，我們的(de)幾個充(chong)(chong)(chong)電器(qi)使(shi)(shi)用(yong)(yong)這種(zhong)技術(shu)，包括打開(kai)和關(guan)閉充(chong)(chong)(chong)電器(qi)以進行電壓測量(liang)(liang)。該技術(shu)似乎(hu)對細胞容量(liang)(liang)的(de)不(bu)平衡(heng)敏感。dT / dt仍然更可(ke)靠，特(te)別(bie)是對于大型包裝(zhuang)，但(dan)在只有(you)兩根電線可(ke)用(yong)(yong)的(de)情況下，現在可(ke)以想想使(shi)(shi)用(yong)(yong)別(bie)的(de)解決(jue)方案。