鋰(li)(li)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)(chi)充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)器是(shi)專門用(yong)來(lai)為鋰(li)(li)離(li)(li)(li)子(zi)(zi)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)(chi)充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)的(de)(de)(de)充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)器。鋰(li)(li)離(li)(li)(li)子(zi)(zi)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)(chi)對充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)器的(de)(de)(de)要(yao)(yao)求較(jiao)高(gao)(gao)，需(xu)(xu)要(yao)(yao)保(bao)護(hu)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)路，所 以鋰(li)(li)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)(chi)充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)器通常都有較(jiao)高(gao)(gao)的(de)(de)(de)控制(zhi)精(jing)密度(du)，能夠(gou)對鋰(li)(li)離(li)(li)(li)子(zi)(zi)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)(chi)進行(xing)恒流(liu)恒壓(ya)充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)。鋰(li)(li)離(li)(li)(li)子(zi)(zi)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)(chi)具有較(jiao)高(gao)(gao)的(de)(de)(de)能量(liang)重量(liang)比和能量(liang)體積(ji)比、無記憶效(xiao)(xiao)應、可重復充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)多次、使用(yong)壽命較(jiao)長、價(jia)格也(ye)越來(lai)越低(di)。鋰(li)(li)離(li)(li)(li)子(zi)(zi)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)(chi)的(de)(de)(de)這些特點促進了便(bian)攜(xie)式產品向更(geng)小更(geng)輕(qing)的(de)(de)(de)方(fang)向發展,使得選(xuan)用(yong)單節鋰(li)(li)離(li)(li)(li)子(zi)(zi)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)(chi)供電(dian)(dian)(dian)(dian)(dian)(dian)(dian)的(de)(de)(de)產品也(ye)越來(lai)越多。鋰(li)(li)離(li)(li)(li)子(zi)(zi)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)(chi)的(de)(de)(de)不(bu)足(zu)之(zhi)處在(zai)于對充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)器要(yao)(yao)求比較(jiao)苛刻,需(xu)(xu)要(yao)(yao)保(bao)護(hu)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)路。鋰(li)(li)離(li)(li)(li)子(zi)(zi)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)(chi)要(yao)(yao)求的(de)(de)(de)充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)方(fang)式是(shi)恒流(liu)恒壓(ya)方(fang)式,為有效(xiao)(xiao)利用(yong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)(chi)容量(liang),需(xu)(xu)將鋰(li)(li)離(li)(li)(li)子(zi)(zi)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)(chi)充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)至最(zui)大(da)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya),但是(shi)過壓(ya)充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)會造成電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)(chi)損(sun)壞,這就要(yao)(yao)求較(jiao)高(gao)(gao)的(de)(de)(de)控制(zhi)精(jing)度(du)。另(ling)外,對于電(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)過低(di)的(de)(de)(de)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)(chi)需(xu)(xu)要(yao)(yao)進行(xing)預充(chong)(chong)(chong),充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)器最(zui)好帶有熱保(bao)護(hu)和時間保(bao)護(hu),為電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)(chi)提(ti)供附(fu)加保(bao)護(hu)。因此，安全(quan)有效(xiao)(xiao)的(de)(de)(de)鋰(li)(li)離(li)(li)(li)子(zi)(zi)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)(chi)充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)器對于鋰(li)(li)離(li)(li)(li)子(zi)(zi)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)(chi)來(lai)說就是(shi)必須而且是(shi)必要(yao)(yao)的(de)(de)(de)。

    鋰(li)電(dian)(dian)池(chi)(chi)充(chong)電(dian)(dian)器(qi)工作原理：鋰(li)離子(zi)電(dian)(dian)池(chi)(chi)充(chong)電(dian)(dian)器(qi)外接限流(liu)型(xing)充(chong)電(dian)(dian)電(dian)(dian)源和Ｐ溝道場效應管(guan),可(ke)以對單節鋰(li)離子(zi)電(dian)(dian)池(chi)(chi)進(jin)行安(an)全有效的(de)快充(chong),其最大(da)特點是在(zai)不使用電(dian)(dian)感的(de)情況(kuang)下仍能(neng)(neng)做到很低的(de)功(gong)率耗散,采用8腳μMAX封(feng)裝。充(chong)電(dian)(dian)控制精(jing)度達0.75％,可(ke)以實現預充(chong)電(dian)(dian),具(ju)有過壓保護(hu)和溫(wen)度保護(hu)功(gong)能(neng)(neng),最長充(chong)電(dian)(dian)時(shi)間限制為鋰(li)離子(zi)電(dian)(dian)池(chi)(chi)提供二次(ci)保護(hu),鋰(li)離子(zi)電(dian)(dian)池(chi)(chi)充(chong)電(dian)(dian)器(qi)的(de)浮充(chong)方式能(neng)(neng)夠使電(dian)(dian)池(chi)(chi)容量充(chong)至最大(da)。

　　當充(chong)(chong)電(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)源(yuan)(yuan)和電(dian)(dian)(dian)(dian)池在正常的(de)(de)(de)工(gong)作溫度范圍內時(shi)(shi)(shi),插入(ru)電(dian)(dian)(dian)(dian)池將(jiang)啟動一次充(chong)(chong)電(dian)(dian)(dian)(dian)過程;充(chong)(chong)電(dian)(dian)(dian)(dian)結(jie)束的(de)(de)(de)條(tiao)件(jian)是平均的(de)(de)(de)脈沖充(chong)(chong)電(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)流(liu)達(da)到(dao)快充(chong)(chong)電(dian)(dian)(dian)(dian)流(liu)的(de)(de)(de)1％,或時(shi)(shi)(shi)間超出片上預置的(de)(de)(de)充(chong)(chong)電(dian)(dian)(dian)(dian)時(shi)(shi)(shi)間。鋰(li)離子電(dian)(dian)(dian)(dian)池充(chong)(chong)電(dian)(dian)(dian)(dian)器能夠自動檢(jian)測充(chong)(chong)電(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)源(yuan)(yuan),沒有電(dian)(dian)(dian)(dian)源(yuan)(yuan)時(shi)(shi)(shi)自動關斷以減少電(dian)(dian)(dian)(dian)池的(de)(de)(de)漏(lou)電(dian)(dian)(dian)(dian)。啟動快充(chong)(chong)后(hou)打開外接的(de)(de)(de)P型場效應管,當檢(jian)測到(dao)電(dian)(dian)(dian)(dian)池電(dian)(dian)(dian)(dian)壓(ya)達(da)到(dao)設(she)定的(de)(de)(de)門(men)限時(shi)(shi)(shi)進入(ru)脈沖充(chong)(chong)電(dian)(dian)(dian)(dian)方式,Ｐ溝道場效應管打開的(de)(de)(de)時(shi)(shi)(shi)間會越來越短(duan),充(chong)(chong)電(dian)(dian)(dian)(dian)結(jie)束時(shi)(shi)(shi),LED指示燈將(jiang)會按(an)12％的(de)(de)(de)周期閃爍(shuo)。

工(gong)作流(liu)程

　　鋰離(li)子電池充電器的工(gong)作狀態流程圖如圖1所示。

　　（1）初始化充電周期

　　鋰離子(zi)(zi)電(dian)(dian)(dian)(dian)池(chi)充(chong)電(dian)(dian)(dian)(dian)器(qi)檢(jian)測到(dao)電(dian)(dian)(dian)(dian)池(chi)和充(chong)電(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)源后(hou)將(jiang)初始化充(chong)電(dian)(dian)(dian)(dian)周期,充(chong)電(dian)(dian)(dian)(dian)結束后(hou),如檢(jian)測到(dao)電(dian)(dian)(dian)(dian)池(chi)電(dian)(dian)(dian)(dian)壓(ya)低于3.89V或(huo)THERM引腳電(dian)(dian)(dian)(dian)壓(ya)高于1.4V將(jiang)重新充(chong)電(dian)(dian)(dian)(dian)。允許快充(chong)的(de)條(tiao)件(jian)是電(dian)(dian)(dian)(dian)池(chi)電(dian)(dian)(dian)(dian)壓(ya)大于2.5V且小于充(chong)電(dian)(dian)(dian)(dian)閾值電(dian)(dian)(dian)(dian)壓(ya)（默認值是4.2V）,而且溫度范圍為2.5°C～47.5°C,如果溫度范圍不符,鋰離子(zi)(zi)電(dian)(dian)(dian)(dian)池(chi)充(chong)電(dian)(dian)(dian)(dian)器(qi)將(jiang)處(chu)于等待(dai)狀態。電(dian)(dian)(dian)(dian)池(chi)電(dian)(dian)(dian)(dian)壓(ya)低于2.5V時,鋰離子(zi)(zi)電(dian)(dian)(dian)(dian)池(chi)充(chong)電(dian)(dian)(dian)(dian)器(qi)用(yong)5mA的(de)電(dian)(dian)(dian)(dian)流預(yu)充(chong),防止深度放電(dian)(dian)(dian)(dian)的(de)鋰離子(zi)(zi)電(dian)(dian)(dian)(dian)池(chi)在快充(chong)時被損壞甚(shen)至發生危險。

　　（2）快充過程

　　快(kuai)充(chong)開(kai)始后,鋰離子電(dian)(dian)池(chi)充(chong)電(dian)(dian)器打開(kai)外接的P溝道場效應管(guan),充(chong)電(dian)(dian)電(dian)(dian)流由外部限流型充(chong)電(dian)(dian)電(dian)(dian)源決定(ding)。由于(yu)P溝道場效應管(guan)工(gong)作在開(kai)關狀態(tai),并非線(xian)性穩壓器,所以功(gong)耗(hao)極小,快(kuai)充(chong)結束的條件是電(dian)(dian)池(chi)電(dian)(dian)壓達到閾值(zhi)（由ADJ引腳調(diao)節）或(huo)充(chong)電(dian)(dian)時間(jian)達到預定(ding)的快(kuai)充(chong)時間(jian)或(huo)溫度(du)超出(chu)安全范圍(wei),溫度(du)超出(chu)工(gong)作范圍(wei)時快(kuai)充(chong)只(zhi)是暫停(ting),當(dang)溫度(du)恢復后快(kuai)充(chong)將(jiang)持續進行。

　　（3）脈沖(chong)充(chong)電(dian)過程

　　多數(shu)情況下充電(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)池(chi)達(da)到(dao)閾值(zhi)后(hou)便結(jie)束(shu)(shu)快充過(guo)程而進入脈沖充電(dian)(dian)(dian)(dian)過(guo)程,鋰(li)離子電(dian)(dian)(dian)(dian)池(chi)充電(dian)(dian)(dian)(dian)器每隔2ms檢測一次電(dian)(dian)(dian)(dian)池(chi)電(dian)(dian)(dian)(dian)壓,電(dian)(dian)(dian)(dian)池(chi)電(dian)(dian)(dian)(dian)壓小(xiao)于(yu)閾值(zhi)時,外部P溝道(dao)(dao)場(chang)(chang)效(xiao)(xiao)(xiao)應管(guan)(guan)導通,電(dian)(dian)(dian)(dian)池(chi)電(dian)(dian)(dian)(dian)壓大(da)于(yu)等于(yu)閾值(zhi)時,P溝道(dao)(dao)場(chang)(chang)效(xiao)(xiao)(xiao)應管(guan)(guan)斷開,脈沖充電(dian)(dian)(dian)(dian)過(guo)程接(jie)近結(jie)束(shu)(shu)時,P溝道(dao)(dao)場(chang)(chang)效(xiao)(xiao)(xiao)應管(guan)(guan)的斷開時間大(da)大(da)超(chao)過(guo)接(jie)通時間,達(da)到(dao)TSEL管(guan)(guan)腳設置的周期(qi)比（1／64,1／128,1／256）后(hou)脈沖充電(dian)(dian)(dian)(dian)過(guo)程結(jie)束(shu)(shu)。

　　（4）充(chong)電狀態指示CHG

　　管(guan)腳(jiao)CHG與(yu)管(guan)腳(jiao)IN之(zhi)間連接(jie)LED作為充電(dian)(dian)狀態指(zhi)示燈,當(dang)沒有插入電(dian)(dian)池或(huo)電(dian)(dian)源沒有連接(jie)或(huo)電(dian)(dian)池電(dian)(dian)壓小于2.2V時(shi),CHG管(guan)腳(jiao)是(shi)高阻(zu)態,LED不亮(liang);當(dang)快充或(huo)脈沖充電(dian)(dian)時(shi),LED亮(liang),在初始化期間或(huo)時(shi)間超出預定時(shi)間,LED按(an)50％的(de)(de)周期閃爍(shuo);當(dang)充電(dian)(dian)狀態結束(shu)時(shi),LED按(an)12％的(de)(de)周期閃爍(shuo)。

典型應用及注意(yi)事項

  

典型應用電路圖

　　圖(tu)２是一個簡單(dan)的單(dan)節鋰離子電池充電器,包括(kuo)：LED顯示、熱敏電阻、電流反(fan)向保護。

　　ADJ引腳通過10kΩ的電(dian)阻與內部 1.4V的精密基準源相(xiang)連接,當ADJ對地沒(mei)有連接電(dian)阻RADJ時,電(dian)池充電(dian)電(dian)壓閾值(zhi)為(wei)缺(que)省值(zhi)：VBR＝4.2V;

　　當需要自行(xing)設置充電(dian)閾值(zhi)(zhi)時,可在ADJ引腳與GND間(jian)接一(yi)精度為1％的電(dian)阻RADJ,阻值(zhi)(zhi)由下(xia)式(shi)確定：

  

阻值

　　圖2電路中,充電閾(yu)值為4.1V,由（１）式得RADJ＝410kΩ,電阻精度為1％時,產(chan)生的系統誤(wu)差為：

  

系統誤差

　　TSEL管腳接BATT或ADJ或GND將得到不同的快(kuai)(kuai)(kuai)充時(shi)(shi)(shi)間(jian)和完整(zheng)的充電時(shi)(shi)(shi)間(jian)。TSEL管腳接BATT時(shi)(shi)(shi)快(kuai)(kuai)(kuai)充時(shi)(shi)(shi)間(jian)為(wei)55分(fen)鐘,全部充電時(shi)(shi)(shi)間(jian)為(wei)2.8小時(shi)(shi)(shi)TSEL接ADJ時(shi)(shi)(shi)快(kuai)(kuai)(kuai)充時(shi)(shi)(shi)間(jian)為(wei)75分(fen)鐘,整(zheng)個充電時(shi)(shi)(shi)間(jian)為(wei)3.75小時(shi)(shi)(shi),TSEL接GND時(shi)(shi)(shi)快(kuai)(kuai)(kuai)充時(shi)(shi)(shi)間(jian)沒有(you)限制,整(zheng)個充電時(shi)(shi)(shi)間(jian)為(wei)6.25小時(shi)(shi)(shi)。充電電流的限制可以采用限流電阻的方法解決。 

鋰電(dian)池充電(dian)器(qi)使用注意事項：

　　　　1.應使充(chong)(chong)(chong)電(dian)(dian)器(qi)的(de)工作選(xuan)擇與被(bei)充(chong)(chong)(chong)電(dian)(dian)池(chi)(chi)一致。如果充(chong)(chong)(chong)電(dian)(dian)器(qi)工作于鋰電(dian)(dian)池(chi)(chi)狀態(tai)而(er)去允(yun)鎳(nie)(nie)氫或(huo)鎳(nie)(nie)鎘電(dian)(dian)池(chi)(chi)，則(ze)(ze)電(dian)(dian)池(chi)(chi)充(chong)(chong)(chong)不滿，會大大減少(shao)工作時(shi)間。如果充(chong)(chong)(chong)電(dian)(dian)器(qi)工作于鎳(nie)(nie)電(dian)(dian)池(chi)(chi)狀態(tai)而(er)去充(chong)(chong)(chong)鋰離子電(dian)(dian)池(chi)(chi)，則(ze)(ze)鋰電(dian)(dian)池(chi)(chi)被(bei)過充(chong)(chong)(chong)，將嚴(yan)重影響(xiang)電(dian)(dian)池(chi)(chi)的(de)壽(shou)命。

　　2.要了解所用充電(dian)(dian)器(qi)充滿點亮(liang)時電(dian)(dian)池是否真的已(yi)充滿。有些充電(dian)(dian)器(qi)見(jian)到充滿指(zhi)示燈亮(liang)即可將鋰電(dian)(dian)池取(qu)下，有些充電(dian)(dian)器(qi)要見(jian)到指(zhi)示燈全亮(liang)才可將電(dian)(dian)池取(qu)下。