鋰(li)(li)(li)(li)電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)器(qi)(qi)是(shi)專門用來(lai)為(wei)鋰(li)(li)(li)(li)離(li)(li)子(zi)電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)的(de)(de)(de)(de)充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)器(qi)(qi)。鋰(li)(li)(li)(li)離(li)(li)子(zi)電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)對充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)器(qi)(qi)的(de)(de)(de)(de)要(yao)求(qiu)較(jiao)高，需(xu)要(yao)保護(hu)電(dian)(dian)(dian)(dian)(dian)(dian)路(lu)，所 以(yi)鋰(li)(li)(li)(li)電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)器(qi)(qi)通常都有(you)較(jiao)高的(de)(de)(de)(de)控(kong)制精密度，能夠對鋰(li)(li)(li)(li)離(li)(li)子(zi)電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)進(jin)行(xing)恒(heng)流恒(heng)壓(ya)充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)。鋰(li)(li)(li)(li)離(li)(li)子(zi)電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)具有(you)較(jiao)高的(de)(de)(de)(de)能量重量比和(he)能量體積比、無記憶效應、可重復充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)多次、使用壽命較(jiao)長、價(jia)格也越(yue)來(lai)越(yue)低(di)。鋰(li)(li)(li)(li)離(li)(li)子(zi)電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)的(de)(de)(de)(de)這些特點促進(jin)了便攜式(shi)產品(pin)向更小更輕的(de)(de)(de)(de)方向發展,使得選用單(dan)節鋰(li)(li)(li)(li)離(li)(li)子(zi)電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)供(gong)電(dian)(dian)(dian)(dian)(dian)(dian)的(de)(de)(de)(de)產品(pin)也越(yue)來(lai)越(yue)多。鋰(li)(li)(li)(li)離(li)(li)子(zi)電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)的(de)(de)(de)(de)不足之(zhi)處在于(yu)對充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)器(qi)(qi)要(yao)求(qiu)比較(jiao)苛刻,需(xu)要(yao)保護(hu)電(dian)(dian)(dian)(dian)(dian)(dian)路(lu)。鋰(li)(li)(li)(li)離(li)(li)子(zi)電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)要(yao)求(qiu)的(de)(de)(de)(de)充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)方式(shi)是(shi)恒(heng)流恒(heng)壓(ya)方式(shi),為(wei)有(you)效利用電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)容量,需(xu)將鋰(li)(li)(li)(li)離(li)(li)子(zi)電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)至(zhi)最大電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya),但是(shi)過(guo)壓(ya)充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)會造成電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)損壞(huai),這就要(yao)求(qiu)較(jiao)高的(de)(de)(de)(de)控(kong)制精度。另外,對于(yu)電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)過(guo)低(di)的(de)(de)(de)(de)電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)需(xu)要(yao)進(jin)行(xing)預充(chong)(chong)(chong),充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)器(qi)(qi)最好(hao)帶有(you)熱(re)保護(hu)和(he)時間(jian)保護(hu),為(wei)電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)提供(gong)附加保護(hu)。因此，安全有(you)效的(de)(de)(de)(de)鋰(li)(li)(li)(li)離(li)(li)子(zi)電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)器(qi)(qi)對于(yu)鋰(li)(li)(li)(li)離(li)(li)子(zi)電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)來(lai)說(shuo)就是(shi)必須而且(qie)是(shi)必要(yao)的(de)(de)(de)(de)。

    鋰(li)(li)電(dian)(dian)(dian)(dian)池(chi)(chi)(chi)充(chong)電(dian)(dian)(dian)(dian)器工作(zuo)原理：鋰(li)(li)離子(zi)電(dian)(dian)(dian)(dian)池(chi)(chi)(chi)充(chong)電(dian)(dian)(dian)(dian)器外接限(xian)流(liu)型(xing)充(chong)電(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)源和Ｐ溝(gou)道(dao)場效(xiao)應管,可(ke)以(yi)對單節鋰(li)(li)離子(zi)電(dian)(dian)(dian)(dian)池(chi)(chi)(chi)進行安全有(you)效(xiao)的快充(chong),其最大(da)特點是在(zai)不使(shi)用(yong)電(dian)(dian)(dian)(dian)感(gan)的情況下仍能做(zuo)到很低(di)的功率耗散,采用(yong)8腳μMAX封裝。充(chong)電(dian)(dian)(dian)(dian)控(kong)制(zhi)精(jing)度(du)達0.75％,可(ke)以(yi)實現預充(chong)電(dian)(dian)(dian)(dian),具有(you)過(guo)壓保護和溫(wen)度(du)保護功能,最長充(chong)電(dian)(dian)(dian)(dian)時間(jian)限(xian)制(zhi)為鋰(li)(li)離子(zi)電(dian)(dian)(dian)(dian)池(chi)(chi)(chi)提供(gong)二次保護,鋰(li)(li)離子(zi)電(dian)(dian)(dian)(dian)池(chi)(chi)(chi)充(chong)電(dian)(dian)(dian)(dian)器的浮(fu)充(chong)方式能夠使(shi)電(dian)(dian)(dian)(dian)池(chi)(chi)(chi)容量充(chong)至最大(da)。

　　當充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)源(yuan)(yuan)和(he)電(dian)(dian)(dian)(dian)池(chi)在正常的(de)(de)(de)工作溫度(du)范(fan)圍內時,插入(ru)電(dian)(dian)(dian)(dian)池(chi)將啟動(dong)一次充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)過程;充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)結束(shu)的(de)(de)(de)條件是平均的(de)(de)(de)脈(mo)(mo)沖充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)流(liu)達到(dao)快充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)流(liu)的(de)(de)(de)1％,或時間超(chao)出片上預(yu)置的(de)(de)(de)充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)時間。鋰離子電(dian)(dian)(dian)(dian)池(chi)充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)器能夠自動(dong)檢(jian)測充(chong)(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)時自動(dong)關(guan)斷(duan)以減少電(dian)(dian)(dian)(dian)池(chi)的(de)(de)(de)漏電(dian)(dian)(dian)(dian)。啟動(dong)快充(chong)(chong)(chong)后(hou)打開外接的(de)(de)(de)P型(xing)場(chang)效應(ying)管(guan),當檢(jian)測到(dao)電(dian)(dian)(dian)(dian)池(chi)電(dian)(dian)(dian)(dian)壓達到(dao)設定的(de)(de)(de)門限(xian)時進入(ru)脈(mo)(mo)沖充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)方式(shi),Ｐ溝道場(chang)效應(ying)管(guan)打開的(de)(de)(de)時間會越來(lai)越短,充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)結束(shu)時,LED指示燈(deng)將會按12％的(de)(de)(de)周期閃爍。

工作流程

　　鋰(li)離子電(dian)(dian)池充電(dian)(dian)器的工作(zuo)狀態流程圖(tu)如(ru)圖(tu)1所示(shi)。

　　（1）初始化充(chong)電周期

　　鋰離(li)(li)子電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)器(qi)檢測到電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池和充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)源后將初始化充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)周期,充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)結束后,如檢測到電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池電(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)低于3.89V或THERM引腳電(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)高于1.4V將重新充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)。允許快充(chong)的(de)條件(jian)是電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池電(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)大(da)于2.5V且小于充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)閾值電(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)（默認(ren)值是4.2V）,而且溫度(du)范(fan)(fan)圍為2.5°C～47.5°C,如果溫度(du)范(fan)(fan)圍不(bu)符,鋰離(li)(li)子電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)器(qi)將處于等待(dai)狀(zhuang)態。電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池電(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)低于2.5V時(shi),鋰離(li)(li)子電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)器(qi)用(yong)5mA的(de)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)流預(yu)充(chong),防止深度(du)放電(dian)(dian)(dian)(dian)(dian)(dian)(dian)的(de)鋰離(li)(li)子電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池在(zai)快充(chong)時(shi)被損壞甚至發(fa)生危(wei)險(xian)。

　　（2）快充過程

　　快(kuai)(kuai)(kuai)充(chong)開始后,鋰離子(zi)電(dian)池(chi)充(chong)電(dian)器(qi)打開外接(jie)的P溝道(dao)場(chang)效應管,充(chong)電(dian)電(dian)流(liu)由(you)外部限(xian)流(liu)型充(chong)電(dian)電(dian)源決(jue)定(ding)。由(you)于P溝道(dao)場(chang)效應管工作在開關狀態,并(bing)非線性穩壓(ya)器(qi),所以功耗極小,快(kuai)(kuai)(kuai)充(chong)結束(shu)的條件是電(dian)池(chi)電(dian)壓(ya)達(da)到(dao)(dao)閾值(zhi)（由(you)ADJ引腳(jiao)調節）或充(chong)電(dian)時(shi)間達(da)到(dao)(dao)預定(ding)的快(kuai)(kuai)(kuai)充(chong)時(shi)間或溫度超出安全范圍,溫度超出工作范圍時(shi)快(kuai)(kuai)(kuai)充(chong)只是暫停(ting),當(dang)溫度恢復后快(kuai)(kuai)(kuai)充(chong)將持續進行。

　　（3）脈沖充電過程

　　多數情況(kuang)下充電(dian)(dian)(dian)電(dian)(dian)(dian)池(chi)(chi)達到(dao)閾(yu)值后便結束快充過(guo)程(cheng)而(er)進(jin)入脈(mo)沖充電(dian)(dian)(dian)過(guo)程(cheng),鋰離(li)子電(dian)(dian)(dian)池(chi)(chi)充電(dian)(dian)(dian)器每隔2ms檢測(ce)一次電(dian)(dian)(dian)池(chi)(chi)電(dian)(dian)(dian)壓,電(dian)(dian)(dian)池(chi)(chi)電(dian)(dian)(dian)壓小于閾(yu)值時(shi),外部P溝道(dao)場(chang)效(xiao)應(ying)管(guan)導通,電(dian)(dian)(dian)池(chi)(chi)電(dian)(dian)(dian)壓大于等于閾(yu)值時(shi),P溝道(dao)場(chang)效(xiao)應(ying)管(guan)斷開,脈(mo)沖充電(dian)(dian)(dian)過(guo)程(cheng)接近(jin)結束時(shi),P溝道(dao)場(chang)效(xiao)應(ying)管(guan)的斷開時(shi)間(jian)大大超(chao)過(guo)接通時(shi)間(jian),達到(dao)TSEL管(guan)腳設置的周期比（1／64,1／128,1／256）后脈(mo)沖充電(dian)(dian)(dian)過(guo)程(cheng)結束。

　　（4）充電狀(zhuang)態指示CHG

　　管腳CHG與管腳IN之間(jian)連(lian)接LED作(zuo)為充電(dian)狀態(tai)指示燈(deng),當沒(mei)有(you)(you)插(cha)入(ru)電(dian)池或(huo)電(dian)源沒(mei)有(you)(you)連(lian)接或(huo)電(dian)池電(dian)壓小于2.2V時,CHG管腳是高阻態(tai),LED不亮;當快充或(huo)脈沖充電(dian)時,LED亮,在(zai)初(chu)始(shi)化期(qi)間(jian)或(huo)時間(jian)超出預定時間(jian),LED按50％的周期(qi)閃爍;當充電(dian)狀態(tai)結束時,LED按12％的周期(qi)閃爍。

典型應用及注意事(shi)項(xiang)

  

典型應用電路圖

　　圖２是一個簡單(dan)(dan)的(de)單(dan)(dan)節(jie)鋰離(li)子(zi)電池充電器,包(bao)括：LED顯示、熱敏電阻、電流反(fan)向保護(hu)。

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

　　當(dang)需要自行設(she)置充(chong)電(dian)閾值時,可在ADJ引腳與GND間接一精度(du)為1％的電(dian)阻(zu)RADJ,阻(zu)值由下(xia)式確(que)定：

  

阻值

　　圖2電(dian)路中,充電(dian)閾值為4.1V,由（１）式得RADJ＝410kΩ,電(dian)阻精度為1％時,產(chan)生(sheng)的系統誤差為：

  

系統誤差

　　TSEL管(guan)(guan)腳(jiao)接BATT或(huo)ADJ或(huo)GND將得到不同的快(kuai)充(chong)(chong)(chong)時(shi)(shi)(shi)間(jian)(jian)和(he)完整的充(chong)(chong)(chong)電(dian)時(shi)(shi)(shi)間(jian)(jian)。TSEL管(guan)(guan)腳(jiao)接BATT時(shi)(shi)(shi)快(kuai)充(chong)(chong)(chong)時(shi)(shi)(shi)間(jian)(jian)為(wei)55分鐘,全部充(chong)(chong)(chong)電(dian)時(shi)(shi)(shi)間(jian)(jian)為(wei)2.8小時(shi)(shi)(shi)TSEL接ADJ時(shi)(shi)(shi)快(kuai)充(chong)(chong)(chong)時(shi)(shi)(shi)間(jian)(jian)為(wei)75分鐘,整個充(chong)(chong)(chong)電(dian)時(shi)(shi)(shi)間(jian)(jian)為(wei)3.75小時(shi)(shi)(shi),TSEL接GND時(shi)(shi)(shi)快(kuai)充(chong)(chong)(chong)時(shi)(shi)(shi)間(jian)(jian)沒有限制,整個充(chong)(chong)(chong)電(dian)時(shi)(shi)(shi)間(jian)(jian)為(wei)6.25小時(shi)(shi)(shi)。充(chong)(chong)(chong)電(dian)電(dian)流的限制可以(yi)采用(yong)限流電(dian)阻的方(fang)法解決。 

鋰(li)電池充電器使(shi)用注意事項(xiang)：

　　　　1.應使充(chong)電(dian)(dian)器的工作選擇與被充(chong)電(dian)(dian)池一(yi)致。如果充(chong)電(dian)(dian)器工作于(yu)鋰電(dian)(dian)池狀態(tai)而去允(yun)鎳氫或鎳鎘(ge)電(dian)(dian)池，則電(dian)(dian)池充(chong)不滿，會大大減少(shao)工作時間。如果充(chong)電(dian)(dian)器工作于(yu)鎳電(dian)(dian)池狀態(tai)而去充(chong)鋰離子電(dian)(dian)池，則鋰電(dian)(dian)池被過充(chong)，將嚴(yan)重(zhong)影響電(dian)(dian)池的壽命。

　　2.要了(le)解(jie)所用充(chong)電(dian)(dian)(dian)器充(chong)滿點亮時電(dian)(dian)(dian)池(chi)(chi)是(shi)否(fou)真的已充(chong)滿。有(you)些充(chong)電(dian)(dian)(dian)器見到充(chong)滿指示燈(deng)亮即可將鋰電(dian)(dian)(dian)池(chi)(chi)取下，有(you)些充(chong)電(dian)(dian)(dian)器要見到指示燈(deng)全亮才可將電(dian)(dian)(dian)池(chi)(chi)取下。