鋰離子電池在充(chong)(chong)電(dian)的過程中包含了(le)慢充(chong)(chong)、快充(chong)(chong)和慢充(chong)(chong)三(san)大(da)階(jie)段，預充(chong)(chong)電(dian)就(jiu)是開(kai)始充(chong)(chong)電(dian)的時候，電(dian)池保(bao)護板為了(le)保(bao)證電(dian)池內部化學(xue)物質反應的安全，會進行(xing)前期的“預熱”，就(jiu)像我們運動時做(zuo)熱身運動一樣。

鋰離子電(dian)(dian)(dian)池工(gong)作電(dian)(dian)(dian)壓(ya)從2.5V（碳負極電(dian)(dian)(dian)池：3V，電(dian)(dian)(dian)量(liang)為0%）到4.2V（電(dian)(dian)(dian)量(liang)為100%）。當(dang)(dang)(dang)電(dian)(dian)(dian)壓(ya)小于2.5V時，電(dian)(dian)(dian)池放(fang)(fang)電(dian)(dian)(dian)終(zhong)止。同(tong)時因為放(fang)(fang)電(dian)(dian)(dian)回(hui)路(lu)關(guan)閉使內(nei)部(bu)保護電(dian)(dian)(dian)路(lu)的電(dian)(dian)(dian)流損耗也降為最低。當(dang)(dang)(dang)然，實(shi)際應用中(zhong)由于不同(tong)的內(nei)部(bu)材質，放(fang)(fang)電(dian)(dian)(dian)終(zhong)止電(dian)(dian)(dian)壓(ya)可(ke)在(zai)2.5V-3.0V范圍(wei)。當(dang)(dang)(dang)電(dian)(dian)(dian)壓(ya)超過(guo)4.2V時，充電(dian)(dian)(dian)回(hui)路(lu)終(zhong)止，以(yi)保護電(dian)(dian)(dian)池安全；而當(dang)(dang)(dang)充電(dian)(dian)(dian)電(dian)(dian)(dian)池工(gong)作電(dian)(dian)(dian)壓(ya)降到3.0V以(yi)下(xia)，我(wo)們即可(ke)認為過(guo)放(fang)(fang)電(dian)(dian)(dian)狀態，放(fang)(fang)電(dian)(dian)(dian)回(hui)路(lu)終(zhong)止，以(yi)保護電(dian)(dian)(dian)池安全。所(suo)以(yi)電(dian)(dian)(dian)池不用時，應將電(dian)(dian)(dian)池充電(dian)(dian)(dian)20%的電(dian)(dian)(dian)量(liang)，再(zai)進行防(fang)潮保存。

由(you)于(yu)鋰離子電池(chi)具有較高的(de)能量比，因此在電池(chi)使用中要嚴格防止過(guo)充(chong)，過(guo)放的(de)現象。過(guo)放會(hui)導(dao)致活(huo)性物(wu)質(zhi)的(de)恢復困(kun)難(nan)，此時假如直接進入快(kuai)速(su)沖電模式（大電流），會(hui)對電池(chi)出現損害，影響使用壽命并可能因此帶來(lai)安全(quan)隱患。先以小電流（C/10）充(chong)到2.5V至3.0V，再轉換成快(kuai)充(chong)是必要的(de)。

雖然目前(qian)鋰離子(zi)電(dian)池在(zai)應用中都(dou)帶有保護板，在(zai)通(tong)常的情況下，發(fa)生過(guo)放(fang)的幾率會很(hen)小，但不加預充功能(neng)，在(zai)這兩種(zhong)情況下的情況還是可(ke)(ke)能(neng)帶來(lai)過(guo)放(fang)的隱患。一是保護板失效，二是長時間放(fang)置(zhi)（5%-10%/月）的自(zi)放(fang)電(dian)率。因此小電(dian)流預充可(ke)(ke)以有效解決過(guo)放(fang)電(dian)池的充電(dian)問(wen)題。

但(dan)是，充(chong)電(dian)電(dian)流并非(fei)越(yue)大越(yue)好。以單體鋰離子電(dian)池為(wei)(wei)例，它的(de)充(chong)電(dian)方式都包(bao)括恒(heng)流、恒(heng)壓(ya)充(chong)電(dian)過程，恒(heng)壓(ya)通常為(wei)(wei)4.2V（以LiCoO2電(dian)池為(wei)(wei)例），恒(heng)流設置值為(wei)(wei)0.1C～1C。雖然大電(dian)流的(de)充(chong)電(dian)會縮(suo)短(duan)充(chong)電(dian)時間，但(dan)也會造成(cheng)電(dian)池生命周(zhou)期的(de)縮(suo)短(duan)和容量的(de)降(jiang)低，因此我們(men)需(xu)選(xuan)擇恰當的(de)恒(heng)流值進(jin)行(xing)充(chong)電(dian)。

通(tong)過(guo)對多個4.2V/900mAHLiCoO2電(dian)(dian)(dian)(dian)芯的(de)(de)不同電(dian)(dian)(dian)(dian)流充電(dian)(dian)(dian)(dian)與電(dian)(dian)(dian)(dian)池(chi)容(rong)量的(de)(de)關系測試(shi)后，通(tong)過(guo)儀(yi)器的(de)(de)曲線，我們可以看出大(da)約500個充放周(zhou)期后，小電(dian)(dian)(dian)(dian)流充電(dian)(dian)(dian)(dian)的(de)(de)電(dian)(dian)(dian)(dian)池(chi)容(rong)量明顯大(da)于大(da)電(dian)(dian)(dian)(dian)流充電(dian)(dian)(dian)(dian)的(de)(de)電(dian)(dian)(dian)(dian)池(chi)容(rong)量。