為(wei)了可以提高(gao)電(dian)(dian)(dian)(dian)池(chi)再充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)期(qi)間的可靠性和(he)穩定性，電(dian)(dian)(dian)(dian)池(chi)充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)機，我(wo)們(men)將使用電(dian)(dian)(dian)(dian)源管理芯片(pian)以控(kong)制電(dian)(dian)(dian)(dian)池(chi)充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)壓(ya)和(he)電(dian)(dian)(dian)(dian)流，但(dan)是使用的電(dian)(dian)(dian)(dian)池(chi)充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)機充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)的電(dian)(dian)(dian)(dian)源管理電(dian)(dian)(dian)(dian)路(lu)的芯片(pian)設計(ji)時(shi)(shi)，我(wo)們(men)往(wang)往(wang)電(dian)(dian)(dian)(dian)池(chi)充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)有(you)(you)工作充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)路(lu)有(you)(you)些混亂機的各個時(shi)(shi)期(qi)的狀態(tai)和(he)電(dian)(dian)(dian)(dian)路(lu)設計(ji)方面(mian)的考慮。

??電池(chi)充電方式簡介

??理論上為了防止因(yin)充(chong)電(dian)不(bu)當(dang)而造成電(dian)池(chi)(chi)壽命縮短，我們將電(dian)池(chi)(chi)的充(chong)電(dian)過程(cheng)分為四(si)個階段：涓(juan)流充(chong)電(dian)(低壓(ya)預充(chong)，此狀態的電(dian)池(chi)(chi)電(dian)壓(ya)比(bi)較低，實際(ji)使用時，建議將鋰電(dian)池(chi)(chi)欠壓(ya)保護點提(ti)高，避(bi)免電(dian)池(chi)(chi)出現過放電(dian)現象)、恒流充(chong)電(dian)、恒壓(ya)充(chong)電(dian)以(yi)及充(chong)電(dian)終止。

??典型的(de)蓄電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)充(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)機充(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)方式(shi)是：先(xian)檢測待充(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)的(de)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)，在電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)較低情況下，先(xian)進行預(yu)充(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)，充(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)為設(she)定(ding)的(de)最大(da)(da)(da)充(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)的(de)1/10，當(dang)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)升到一定(ding)值后，進入標(biao)準充(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)過(guo)程。標(biao)準充(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)過(guo)程為：以最大(da)(da)(da)充(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)進行恒(heng)流(liu)充(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)，電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)持續(xu)穩定(ding)上升，當(dang)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)升到接近設(she)定(ding)的(de)最大(da)(da)(da)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)時，改為恒(heng)壓(ya)(ya)(ya)充(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)，此時，充(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)逐(zhu)漸(jian)下降，當(dang)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)下降至最大(da)(da)(da)充(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)的(de)1/10時，充(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)結(jie)束。

??但在實(shi)際應用中，為(wei)增加電(dian)池充(chong)(chong)(chong)放(fang)電(dian)循(xun)環次數和縮短充(chong)(chong)(chong)電(dian)時(shi)間，我們會將鋰電(dian)池欠壓保護(hu)點提高，同時(shi)設定的充(chong)(chong)(chong)電(dian)終止電(dian)壓低于標稱值，這樣電(dian)池便不會存在過充(chong)(chong)(chong)與過放(fang)現象，且可(ke)以避開“預充(chong)(chong)(chong)電(dian)”階段，直接進行大(da)電(dian)流(liu)充(chong)(chong)(chong)電(dian)，縮短充(chong)(chong)(chong)電(dian)時(shi)間。

??充電機電路設計應注意的事項

??若(ruo)設計的(de)(de)(de)蓄電(dian)(dian)(dian)(dian)池(chi)(chi)充電(dian)(dian)(dian)(dian)機(ji)充電(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)路沒(mei)有(you)防倒灌(guan)(guan)保護，將會產生(sheng)許多危害。以輸(shu)(shu)出端接(jie)2節鋰(li)電(dian)(dian)(dian)(dian)池(chi)(chi)串聯為例，若(ruo)僅將電(dian)(dian)(dian)(dian)源去除，蓄電(dian)(dian)(dian)(dian)池(chi)(chi)充電(dian)(dian)(dian)(dian)機(ji)沒(mei)有(you)移除，電(dian)(dian)(dian)(dian)池(chi)(chi)內的(de)(de)(de)電(dian)(dian)(dian)(dian)流倒灌(guan)(guan)至充電(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)路中，導致電(dian)(dian)(dian)(dian)池(chi)(chi)電(dian)(dian)(dian)(dian)量白(bai)(bai)白(bai)(bai)損(sun)失。且更嚴(yan)重的(de)(de)(de)安全隱(yin)患是：對于(yu)降壓(ya)電(dian)(dian)(dian)(dian)源芯片(pian)來說(shuo)，電(dian)(dian)(dian)(dian)池(chi)(chi)電(dian)(dian)(dian)(dian)流從輸(shu)(shu)出端，經芯片(pian)內部功(gong)率管寄生(sheng)的(de)(de)(de)二極(ji)管倒灌(guan)(guan)至芯片(pian)的(de)(de)(de)VIN端，當(dang)電(dian)(dian)(dian)(dian)路的(de)(de)(de)輸(shu)(shu)出端電(dian)(dian)(dian)(dian)壓(ya)(電(dian)(dian)(dian)(dian)池(chi)(chi)電(dian)(dian)(dian)(dian)壓(ya))低(di)(di)(di)于(yu)設定值(zhi)時，芯片(pian)FB點(dian)電(dian)(dian)(dian)(dian)壓(ya)相應的(de)(de)(de)也會低(di)(di)(di)于(yu)標(biao)稱值(zhi)，芯片(pian)開始(shi)工(gong)(gong)作來提(ti)高(gao)輸(shu)(shu)出端電(dian)(dian)(dian)(dian)壓(ya);由于(yu)輸(shu)(shu)入(ru)端電(dian)(dian)(dian)(dian)壓(ya)幾(ji)乎與輸(shu)(shu)出端相等，對于(yu)降壓(ya)芯片(pian)來說(shuo)，輸(shu)(shu)入(ru)端無法給(gei)輸(shu)(shu)出端提(ti)供能量，導致FB點(dian)電(dian)(dian)(dian)(dian)壓(ya)一直(zhi)低(di)(di)(di)于(yu)標(biao)稱值(zhi)，芯片(pian)進入(ru)占空(kong)比100%的(de)(de)(de)工(gong)(gong)作狀態(tai)。

??如(ru)果輸(shu)(shu)入端的電(dian)源(yuan)突然恢復(fu)，則(ze)輸(shu)(shu)入端的電(dian)源(yuan)將(jiang)通過已接通的電(dian)源(yuan)管(guan)將(jiang)能量(liang)直接傳(chuan)輸(shu)(shu)到輸(shu)(shu)出(chu)端。由于(yu)輸(shu)(shu)入和輸(shu)(shu)出(chu)之間(jian)的壓差，一個相對較(jiao)大的電(dian)流(liu)(liu)會在瞬間(jian)流(liu)(liu)過功率管(guan)。如(ru)果此(ci)時由于(yu)其他不(bu)可(ke)(ke)控(kong)制的原因，導(dao)致(zhi)核心不(bu)能及(ji)時有效地響應關(guan)閉電(dian)源(yuan)管(guan)，則(ze)大電(dian)流(liu)(liu)可(ke)(ke)能導(dao)致(zhi)芯片至部分開關(guan)管(guan)損壞。因此(ci)，在蓄電(dian)池充(chong)電(dian)電(dian)路的設計中需要增加防回流(liu)(liu)措(cuo)施。