日益發達的便攜式電子產品對可充電電池的容量和循環壽命等性能要求越來越高. 目前常用的有四大類, 鎳鎘電池和鉛酸免維護電池這兩類在上世紀六十年代已經普遍推廣, 鎳氫電池和鋰離子電池(含鋰聚合物電池)這兩大類是近十年才大量商業化使用. 這四大類電池各有所長, 下表給出了一個基本參考, 不同電池生產廠家的具體數值可能有較大差別, 使用時咨詢生產廠家, 表中的數據僅供比較參考使用.
比較項目 鉛酸免維護電池(SLA) 鎳鎘電池(NICD) 鎳氫電池(NIMH) 鋰離子電池(LI-ION)
能量密度(Wh/kg) 30 40 60 100
循環壽命(次) 300 800 500 800
工作溫度 (°C) 0~35 0~45 0~40 0~50
允許的最大充電電流(A) 0.25C 2C 1C 1C
充電方式 恒流后恒壓 恒流 恒流 恒流后恒壓
充電完成時間 (小時) C/A + 2 hours C/A + 20% C/A + 20% C/A × 2
表中C 為電池的標稱容量, 單位為AH(安時), A 表示充電恒流電流
人們當然希望充電器能在短時間內充電完成, 但是由于電流大且控制難, 這在成本和技術方面都有一定程度的代價付出. 如果使用條件允許, 選用10~14 個小時左右充電結束的夜晚慢充型充電器會有價格低,體積小巧等優點.對于在線并連使用的SLA 電池, 充電方式建議選用2.27V/單元(對應12V 電池為13.7V)恒壓充電, 這種方案既不會過充電池, 也有利于穩定設備電壓. 對于要經常離線充放電使用SLA 電池的場合, 應該使用先0.2C 恒流, 再2.45V/單元恒壓, 電池充好后即時進入2.27V/單元恒壓的"三段式"充電方法. 整個充電時間約為8~10 小時.NICD 電池允許有一定電流的過充, 因此選用0.1C 電流的簡單恒流源充電器可謂經濟實惠.
NIMH 電池對過充電較為敏感, 即使用0.1C 的電流, 如果充電超過14 個小時或對已充好的電池再繼續充幾個小時, 對電池的壽命都有較大損害. 電池充好時應及時關斷電流或將充電電流降低到0.02C 以下是非常重要的, 即對0.1C 的夜間慢充型NIMH 充電器也是如此.最大充電電流達到2C 左右的智能型快速充電器已經有很多成功案例. 這類充電器一般都必須在充電進程的各階段隨時監測電池電壓、溫度等參數，當電池快要充滿電時自動降低充電電流倍率，這樣可以將電池過充電引起的過溫過壓風險降到最低。NICD 和NIMH 兩類電池的充電特性非常相似，只是NIMH 電池在充電過程中發熱更多一些、峰值電壓更不明顯一些。這兩類電池在快速充電時都采用下面幾種條件之一來作為快充電終止的條件：包括電壓上升斜率（dV/dt)、電壓負增長
（-dV)和(he)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)溫度上升斜率（dT/dt)。還有(you)(you)三個條件(jian)是(shi)(shi)設置(zhi)為(wei)異常保(bao)護(hu)(hu)條件(jian)下(xia)進行動(dong)作(zuo)的(de)(de)(de)(de)：最(zui)高電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)溫度、最(zui)高電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓和(he)充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)器內置(zhi)定(ding)時器。要(yao)(yao)實(shi)現這些監測和(he)智能切換動(dong)作(zuo)，肯定(ding)要(yao)(yao)帶來充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)器成(cheng)本上升，但(dan)是(shi)(shi)如果沒(mei)有(you)(you)這些措(cuo)施，電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)將面臨著容量下(xia)降、循(xun)環壽命降低甚至漏(lou)液(ye)爆炸等安(an)全隱患。LI-ION 和(he)SLA 電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)的(de)(de)(de)(de)充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)方式(shi)較為(wei)相似，都要(yao)(yao)求先恒流再恒壓，區(qu)別(bie)是(shi)(shi)鋰(li)離子(zi)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)對充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)恒壓階(jie)段(duan)的(de)(de)(de)(de)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓精度要(yao)(yao)求較高（<1%)。由于鋰(li)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)的(de)(de)(de)(de)安(an)全性(xing)是(shi)(shi)一個致命的(de)(de)(de)(de)隱患，因(yin)此(ci)要(yao)(yao)求在充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)結束(shu)控制(zhi)和(he)保(bao)護(hu)(hu)方面要(yao)(yao)特別(bie)小心。對不同的(de)(de)(de)(de)應用場合，鋰(li)離子(zi)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)包都會內置(zhi)有(you)(you)相應的(de)(de)(de)(de)充(chong)(chong)(chong)放電(dian)(dian)(dian)(dian)(dian)(dian)(dian)保(bao)護(hu)(hu)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)路(lu), 以便更(geng)安(an)全的(de)(de)(de)(de)保(bao)護(hu)(hu)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)不發生意外.