電(dian)(dian)池在42.5V～43.5V時(shi)(shi)開始(shi)析(xi)(xi)氣(qi)(qi)(qi),而析(xi)(xi)氣(qi)(qi)(qi)的(de)速(su)度與(yu)充(chong)(chong)電(dian)(dian)電(dian)(dian)壓有(you)關。到充(chong)(chong)電(dian)(dian)結(jie)束時(shi)(shi)，總(zong)析(xi)(xi)氣(qi)(qi)(qi)量(liang)(liang)與(yu)充(chong)(chong)電(dian)(dian)最高電(dian)(dian)壓有(you)關，43V與(yu)45V總(zong)析(xi)(xi)氣(qi)(qi)(qi)量(liang)(liang)相(xiang)差10位（注(zhu)：以(yi)單格(ge)允(yun)許極(ji)限(xian)失(shi)水10克，18格(ge)相(xiang)當240公(gong)升氣(qi)(qi)(qi)體，該電(dian)(dian)池45V時(shi)(shi)失(shi)水并不大(da)）。 在充(chong)(chong)電(dian)(dian)末期(qi)電(dian)(dian)流下(xia)降(jiang)(jiang)區(qu)時(shi)(shi)，只要降(jiang)(jiang)低電(dian)(dian)壓到42.5V時(shi)(shi)，析(xi)(xi)氣(qi)(qi)(qi)立即停止，這(zhe)時(shi)(shi)充(chong)(chong)電(dian)(dian)電(dian)(dian)流稍小一點，還會依著原來(lai)的(de)規(gui)律下(xia)降(jiang)(jiang)。

　　這里對浮充電壓、浮充電流討論一下。對于長期處于浮充狀態下的鉛酸電池組，如后備電源上用的等，對浮充電壓要求是嚴格的。據國處文獻，浮充電壓有-0.2%溫度系數，浮充電壓偏差太大會造成電池鹽化。而電動車用的電池屬循環使用，不是處于這種狀態，不應該用套用浮充狀態使用的條件，充電器設定浮(fu)充(chong)(chong)的目的僅是免于充(chong)(chong)電(dian)(dian)末(mo)期大量析(xi)(xi)氣(qi)失水(shui)，只要把電(dian)(dian)壓降到析(xi)(xi)氣(qi)點電(dian)(dian)壓以下，但也不(bu)能低(di)于電(dian)(dian)池端電(dian)(dian)壓而停止向電(dian)(dian)池充(chong)(chong)電(dian)(dian)。前面(mian)說過，在(zai)浮(fu)充(chong)(chong)電(dian)(dian)壓下，充(chong)(chong)電(dian)(dian)電(dian)(dian)流(liu)的走勢基本還(huan)是依著(zhu)原(yuan)曲(qu)線下降，一般還(huan)補(bu)足5%的容量。所以浮(fu)充(chong)(chong)電(dian)(dian)壓應(ying)在(zai)的范圍是低(di)于析(xi)(xi)氣(qi)電(dian)(dian)壓（42.5V），高于電(dian)(dian)池充(chong)(chong)足電(dian)(dian)以后的開路(lu)端電(dian)(dian)壓（約40V）。

　　浮充(chong)(chong)(chong)(chong)(chong)轉(zhuan)換(huan)(huan)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流，只不過(guo)是(shi)(shi)選擇在充(chong)(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)末(mo)(mo)期(qi)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)活性(xing)物質(zhi)反應接近尾聲(sheng)，充(chong)(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流自動下(xia)降到某一(yi)(yi)(yi)點(dian)時(shi)，切換(huan)(huan)浮充(chong)(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)的記號，不少(shao)人(ren)以(yi)為浮充(chong)(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流高了(le)(le)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)會充(chong)(chong)(chong)(chong)(chong)不滿是(shi)(shi)概(gai)念(nian)不清，充(chong)(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)只要(yao)高于電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)端電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)，都(dou)會對(dui)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)充(chong)(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)，只不過(guo)有(you)(you)用(yong)(yong)戶看到指示(shi)燈(deng)紅轉(zhuan)綠(lv)后(hou)提前去用(yong)(yong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)，這(zhe)種情(qing)況(kuang)是(shi)(shi)不多的，一(yi)(yi)(yi)般都(dou)是(shi)(shi)夜(ye)間(jian)(jian)充(chong)(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)，到早晨綠(lv)燈(deng)已亮了(le)(le)多時(shi)。有(you)(you)的廠家使用(yong)(yong)說(shuo)明書上提醒用(yong)(yong)戶，在轉(zhuan)綠(lv)燈(deng)后(hou)繼(ji)續(xu)充(chong)(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)2小時(shi)，是(shi)(shi)很(hen)好很(hen)正確的。所以(yi)沒有(you)(you)必要(yao)刻(ke)意(yi)去追求浮充(chong)(chong)(chong)(chong)(chong)轉(zhuan)換(huan)(huan)點(dian)的高低(di)，一(yi)(yi)(yi)般新(xin)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)末(mo)(mo)期(qi)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流約為50mA，失(shi)水以(yi)后(hou)，酸比(bi)增高，那(nei)時(shi)可(ke)達500 mA以(yi)上。從析氣速率(lv)與電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)的關系上來看（上圖(tu)），早點(dian)脫離析氣區為好，一(yi)(yi)(yi)方面(mian)，一(yi)(yi)(yi)方面(mian)可(ke)以(yi)減少(shao)析氣量(liang)，另一(yi)(yi)(yi)方面(mian)，電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)用(yong)(yong)了(le)(le)一(yi)(yi)(yi)段(duan)時(shi)間(jian)(jian)，末(mo)(mo)期(qi)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流增高，但還(huan)能低(di)于我們設(she)定(ding)的轉(zhuan)換(huan)(huan)點(dian)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流，否則(ze)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)一(yi)(yi)(yi)直在最高電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)充(chong)(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)下(xia)，大(da)量(liang)失(shi)水，引發熱(re)控，充(chong)(chong)(chong)(chong)(chong)脹充(chong)(chong)(chong)(chong)(chong)壞電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)。有(you)(you)人(ren)固執地強(qiang)調，浮充(chong)(chong)(chong)(chong)(chong)轉(zhuan)換(huan)(huan)點(dian)高電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)會欠充(chong)(chong)(chong)(chong)(chong)，前面(mian)已討論過(guo)，切換(huan)(huan)到浮充(chong)(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)后(hou)，不是(shi)(shi)停止(zhi)充(chong)(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)了(le)(le)，還(huan)會繼(ji)續(xu)對(dui)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)充(chong)(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)的，轉(zhuan)換(huan)(huan)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流適當(dang)高一(yi)(yi)(yi)點(dian)有(you)(you)利于避(bi)免(mian)過(guo)分失(shi)水和(he)熱(re)失(shi)控。

　　至于充電電流的大小設定，先看一下電池制造廠家對10Ah（12Ah）吸附式小型密封電池對充電時的技術要求，通常規定充電速率不要大于0.3C，相當于4A電流，而充電器充電電流(liu)(liu)在(zai)2A左右，遠離極限充電電流(liu)(liu)。