為了(le)可以(yi)提高電(dian)(dian)(dian)(dian)(dian)池再充(chong)電(dian)(dian)(dian)(dian)(dian)期間(jian)的(de)(de)可靠性和(he)(he)穩定性，電(dian)(dian)(dian)(dian)(dian)池充(chong)電(dian)(dian)(dian)(dian)(dian)機，我(wo)們將使用電(dian)(dian)(dian)(dian)(dian)源管(guan)理(li)芯(xin)片(pian)以(yi)控制(zhi)電(dian)(dian)(dian)(dian)(dian)池充(chong)電(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)壓和(he)(he)電(dian)(dian)(dian)(dian)(dian)流，但是使用的(de)(de)電(dian)(dian)(dian)(dian)(dian)池充(chong)電(dian)(dian)(dian)(dian)(dian)機充(chong)電(dian)(dian)(dian)(dian)(dian)的(de)(de)電(dian)(dian)(dian)(dian)(dian)源管(guan)理(li)電(dian)(dian)(dian)(dian)(dian)路的(de)(de)芯(xin)片(pian)設計時，我(wo)們往往電(dian)(dian)(dian)(dian)(dian)池充(chong)電(dian)(dian)(dian)(dian)(dian)有工(gong)作充(chong)電(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)路有些混亂機的(de)(de)各(ge)個時期的(de)(de)狀(zhuang)態和(he)(he)電(dian)(dian)(dian)(dian)(dian)路設計方(fang)面(mian)的(de)(de)考慮。

??電(dian)池充電(dian)方式簡介

??理論上(shang)為了防止因(yin)充(chong)(chong)(chong)電(dian)不當而造成電(dian)池(chi)壽(shou)命縮(suo)短，我們(men)將(jiang)電(dian)池(chi)的充(chong)(chong)(chong)電(dian)過程分為四個階段：涓流充(chong)(chong)(chong)電(dian)(低壓(ya)預充(chong)(chong)(chong)，此狀態(tai)的電(dian)池(chi)電(dian)壓(ya)比較低，實(shi)際使用時，建議將(jiang)鋰(li)電(dian)池(chi)欠壓(ya)保護點提高，避免電(dian)池(chi)出現過放(fang)電(dian)現象(xiang))、恒流充(chong)(chong)(chong)電(dian)、恒壓(ya)充(chong)(chong)(chong)電(dian)以及充(chong)(chong)(chong)電(dian)終止。

??典型的蓄電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)充(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)機充(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)方式是：先檢測(ce)待充(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)的電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)，在(zai)電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)較低情況(kuang)下(xia)，先進行預(yu)充(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)，充(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)(dian)流(liu)為(wei)設(she)定的最(zui)大充(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)(dian)流(liu)的1/10，當電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)升到一定值(zhi)后，進入標準(zhun)充(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)過程。標準(zhun)充(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)過程為(wei)：以最(zui)大充(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)(dian)流(liu)進行恒(heng)流(liu)充(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)，電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)持續(xu)穩定上升，當電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)升到接(jie)近設(she)定的最(zui)大電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)時(shi)，改為(wei)恒(heng)壓(ya)充(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)，此(ci)時(shi)，充(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)(dian)流(liu)逐漸(jian)下(xia)降，當電(dian)(dian)(dian)(dian)(dian)(dian)流(liu)下(xia)降至最(zui)大充(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)(dian)流(liu)的1/10時(shi)，充(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)結束。

??但在實際應(ying)用中(zhong)，為增加電(dian)(dian)(dian)池(chi)(chi)充(chong)放電(dian)(dian)(dian)循環(huan)次數(shu)和縮短(duan)充(chong)電(dian)(dian)(dian)時(shi)間，我(wo)們會將鋰電(dian)(dian)(dian)池(chi)(chi)欠壓(ya)保護點提高，同(tong)時(shi)設定的充(chong)電(dian)(dian)(dian)終(zhong)止電(dian)(dian)(dian)壓(ya)低(di)于標(biao)稱(cheng)值(zhi)，這樣(yang)電(dian)(dian)(dian)池(chi)(chi)便不會存在過充(chong)與(yu)過放現象，且可以避開“預充(chong)電(dian)(dian)(dian)”階段(duan)，直接(jie)進行大(da)電(dian)(dian)(dian)流充(chong)電(dian)(dian)(dian)，縮短(duan)充(chong)電(dian)(dian)(dian)時(shi)間。

??充電機電路設計應注意的事項

??若設計的(de)蓄電(dian)(dian)(dian)池充電(dian)(dian)(dian)機充電(dian)(dian)(dian)電(dian)(dian)(dian)路(lu)(lu)沒有防倒(dao)(dao)灌(guan)保護，將(jiang)(jiang)會產生許(xu)多危害。以輸(shu)出(chu)(chu)(chu)(chu)端(duan)(duan)(duan)(duan)接2節鋰電(dian)(dian)(dian)池串聯為例(li)，若僅將(jiang)(jiang)電(dian)(dian)(dian)源去除(chu)，蓄電(dian)(dian)(dian)池充電(dian)(dian)(dian)機沒有移除(chu)，電(dian)(dian)(dian)池內的(de)電(dian)(dian)(dian)流倒(dao)(dao)灌(guan)至(zhi)充電(dian)(dian)(dian)電(dian)(dian)(dian)路(lu)(lu)中(zhong)，導致電(dian)(dian)(dian)池電(dian)(dian)(dian)量白白損失(shi)。且更嚴重的(de)安全隱患是：對(dui)于(yu)(yu)(yu)降壓(ya)(ya)電(dian)(dian)(dian)源芯片(pian)(pian)來說，電(dian)(dian)(dian)池電(dian)(dian)(dian)流從輸(shu)出(chu)(chu)(chu)(chu)端(duan)(duan)(duan)(duan)，經芯片(pian)(pian)內部功率管寄生的(de)二極(ji)管倒(dao)(dao)灌(guan)至(zhi)芯片(pian)(pian)的(de)VIN端(duan)(duan)(duan)(duan)，當電(dian)(dian)(dian)路(lu)(lu)的(de)輸(shu)出(chu)(chu)(chu)(chu)端(duan)(duan)(duan)(duan)電(dian)(dian)(dian)壓(ya)(ya)(電(dian)(dian)(dian)池電(dian)(dian)(dian)壓(ya)(ya))低(di)于(yu)(yu)(yu)設定值時，芯片(pian)(pian)FB點(dian)電(dian)(dian)(dian)壓(ya)(ya)相(xiang)(xiang)應的(de)也會低(di)于(yu)(yu)(yu)標稱值，芯片(pian)(pian)開始工(gong)作來提高輸(shu)出(chu)(chu)(chu)(chu)端(duan)(duan)(duan)(duan)電(dian)(dian)(dian)壓(ya)(ya);由于(yu)(yu)(yu)輸(shu)入端(duan)(duan)(duan)(duan)電(dian)(dian)(dian)壓(ya)(ya)幾乎(hu)與輸(shu)出(chu)(chu)(chu)(chu)端(duan)(duan)(duan)(duan)相(xiang)(xiang)等(deng)，對(dui)于(yu)(yu)(yu)降壓(ya)(ya)芯片(pian)(pian)來說，輸(shu)入端(duan)(duan)(duan)(duan)無法(fa)給輸(shu)出(chu)(chu)(chu)(chu)端(duan)(duan)(duan)(duan)提供能量，導致FB點(dian)電(dian)(dian)(dian)壓(ya)(ya)一(yi)直(zhi)低(di)于(yu)(yu)(yu)標稱值，芯片(pian)(pian)進入占空比(bi)100%的(de)工(gong)作狀(zhuang)態。

??如果(guo)輸(shu)入端(duan)的(de)電源突然恢復，則輸(shu)入端(duan)的(de)電源將通過已接(jie)通的(de)電源管將能量直(zhi)接(jie)傳輸(shu)到(dao)輸(shu)出端(duan)。由(you)于(yu)輸(shu)入和輸(shu)出之間(jian)的(de)壓(ya)差，一個相對(dui)較大(da)的(de)電流會在(zai)瞬(shun)間(jian)流過功率管。如果(guo)此(ci)(ci)時(shi)由(you)于(yu)其他(ta)不可(ke)控制的(de)原因(yin)，導致核心不能及時(shi)有效地響應關閉電源管，則大(da)電流可(ke)能導致芯(xin)片至部分開(kai)關管損(sun)壞。因(yin)此(ci)(ci)，在(zai)蓄電池(chi)充電電路的(de)設計中需(xu)要增加防回(hui)流措(cuo)施。