電(dian)(dian)池(chi)(chi)組制(zhi)造商(shang)來說(shuo)，針對(dui)電(dian)(dian)池(chi)(chi)供(gong)(gong)電(dian)(dian)系(xi)統(tong)構建安(an)全且(qie)可(ke)靠的(de)(de)(de)產品是至(zhi)關重(zhong)要(yao)的(de)(de)(de)。電(dian)(dian)池(chi)(chi)包(bao)中的(de)(de)(de)電(dian)(dian)池(chi)(chi)管(guan)(guan)理電(dian)(dian)路(lu)(lu)可(ke)以(yi)(yi)監(jian)控鋰離子(zi)(zi)電(dian)(dian)池(chi)(chi)的(de)(de)(de)運(yun)行狀(zhuang)態，包(bao)括了電(dian)(dian)池(chi)(chi)阻(zu)抗、溫度、單(dan)(dan)元(yuan)(yuan)(yuan)電(dian)(dian)壓、充(chong)電(dian)(dian)和(he)放電(dian)(dian)電(dian)(dian)流以(yi)(yi)及充(chong)電(dian)(dian)狀(zhuang)態等，以(yi)(yi)為系(xi)統(tong)提供(gong)(gong)詳細(xi)的(de)(de)(de)剩(sheng)余運(yun)轉時間和(he)電(dian)(dian)池(chi)(chi)健康(kang)狀(zhuang)況信息，確保(bao)系(xi)統(tong)作出正(zheng)確的(de)(de)(de)決策(ce)。此外，為了改進電(dian)(dian)池(chi)(chi)的(de)(de)(de)安(an)全性能，即使只有一種故障發生，例如過(guo)電(dian)(dian)流、短路(lu)(lu)、單(dan)(dan)元(yuan)(yuan)(yuan)和(he)電(dian)(dian)池(chi)(chi)包(bao)的(de)(de)(de)電(dian)(dian)壓過(guo)高(gao)、溫度過(guo)高(gao)等，系(xi)統(tong)也會關閉兩個和(he)鋰離子(zi)(zi)電(dian)(dian)池(chi)(chi)串聯的(de)(de)(de)背(bei)靠背(bei)（back-to-back）保(bao)護MOSFET，將電(dian)(dian)池(chi)(chi)單(dan)(dan)元(yuan)(yuan)(yuan)斷開。基于阻(zu)抗跟(gen)蹤技(ji)術的(de)(de)(de)電(dian)(dian)池(chi)(chi)管(guan)(guan)理單(dan)(dan)元(yuan)(yuan)(yuan)（BMS）會在(zai)整個電(dian)(dian)池(chi)(chi)使用(yong)周期內監(jian)控單(dan)(dan)元(yuan)(yuan)(yuan)阻(zu)抗和(he)電(dian)(dian)壓失衡，并有可(ke)能檢測(ce)電(dian)(dian)池(chi)(chi)的(de)(de)(de)微小短路(lu)(lu)（micro-short），防止電(dian)(dian)池(chi)(chi)單(dan)(dan)元(yuan)(yuan)(yuan)造成火災乃至(zhi)爆炸。

鋰離子電池安全

       過高的工作溫度將加速電池的老化，并可能導致鋰離子電池包的熱失控（thermal run-away）及爆炸。對于鋰離子電池高度活性化的含能材料來說，這一點是備受關注的。大電流的過度充電及短路都有可能造成電池溫度的快速上升。鋰離子電池過度充(chong)電(dian)(dian)期(qi)間，活躍得金屬(shu)鋰沉積在電(dian)(dian)池的(de)(de)(de)正極(ji)，其材(cai)料(liao)極(ji)大的(de)(de)(de)增(zeng)加了(le)爆炸(zha)的(de)(de)(de)危(wei)險性，因為鋰將有可能(neng)與(yu)多種材(cai)料(liao)起反應(ying)而爆炸(zha)，包括了(le)電(dian)(dian)解(jie)(jie)液(ye)及陰(yin)極(ji)材(cai)料(liao)。例(li)如(ru)，鋰/碳插層混(hun)合物（intercalated compound）與(yu)水發生(sheng)反應(ying)，并釋放出氫氣，氫氣有可能(neng)被反應(ying)放熱所引燃。陰(yin)極(ji)材(cai)料(liao)，諸如(ru)LiCoO2，在溫(wen)度超過175℃的(de)(de)(de)熱失控溫(wen)度限（4.3V單元電(dian)(dian)壓）時，也將開始(shi)與(yu)電(dian)(dian)解(jie)(jie)液(ye)發生(sheng)反應(ying)。

      鋰離子(zi)(zi)電(dian)池(chi)使(shi)(shi)用(yong)很薄的(de)(de)(de)(de)(de)(de)(de)微孔膜(mo)（micro-porous film）材(cai)料(liao)，例(li)如聚烯(xi)烴，進行電(dian)池(chi)正負(fu)極(ji)的(de)(de)(de)(de)(de)(de)(de)電(dian)子(zi)(zi)隔(ge)離，因為(wei)此類材(cai)料(liao)具有(you)卓越的(de)(de)(de)(de)(de)(de)(de)力學性能(neng)(neng)、化學穩定性以及(ji)可接受的(de)(de)(de)(de)(de)(de)(de)價格。聚烯(xi)烴的(de)(de)(de)(de)(de)(de)(de)熔(rong)點范(fan)圍較低，為(wei)135℃至(zhi)(zhi) 165℃，使(shi)(shi)得(de)聚烯(xi)烴適用(yong)于作為(wei)熱(re)保險(xian)（fuse）材(cai)料(liao)。隨著(zhu)溫(wen)度的(de)(de)(de)(de)(de)(de)(de)升高并(bing)達到(dao)聚合體的(de)(de)(de)(de)(de)(de)(de)熔(rong)點，材(cai)料(liao)的(de)(de)(de)(de)(de)(de)(de)多孔性將失效(xiao)，其(qi)目的(de)(de)(de)(de)(de)(de)(de)是(shi)使(shi)(shi)得(de)鋰離子(zi)(zi)無法在電(dian)極(ji)之(zhi)間流動，從而(er)關斷電(dian)池(chi)。同時，熱(re)敏陶瓷(ci)（PCT）設備以及(ji)安全排出口（safety vent）為(wei)鋰離子(zi)(zi)電(dian)池(chi)提(ti)供(gong)了額外的(de)(de)(de)(de)(de)(de)(de)保護。電(dian)池(chi)的(de)(de)(de)(de)(de)(de)(de)外殼(ke)，一般作為(wei)負(fu)極(ji)接線端，通常(chang)為(wei)典型的(de)(de)(de)(de)(de)(de)(de)鍍鎳(nie)金屬板。在殼(ke)體密封(feng)的(de)(de)(de)(de)(de)(de)(de)情況(kuang)下，金屬微粒將可能(neng)(neng)污染電(dian)池(chi)的(de)(de)(de)(de)(de)(de)(de)內(nei)部。隨著(zhu)時間的(de)(de)(de)(de)(de)(de)(de)推移(yi)(yi)，微粒有(you)可能(neng)(neng)遷移(yi)(yi)至(zhi)(zhi)隔(ge)離器(qi)，并(bing)使(shi)(shi)得(de)電(dian)池(chi)陽極(ji)與(yu)陰極(ji)之(zhi)間的(de)(de)(de)(de)(de)(de)(de)絕(jue)緣層老化。而(er)陽極(ji)與(yu)陰極(ji)之(zhi)間的(de)(de)(de)(de)(de)(de)(de)微小短路將允(yun)許(xu)電(dian)子(zi)(zi)肆意的(de)(de)(de)(de)(de)(de)(de)流動，并(bing)最終(zhong)(zhong)使(shi)(shi)電(dian)池(chi)失效(xiao)。絕(jue)大(da)多數(shu)情況(kuang)下，此類失效(xiao)等同于電(dian)池(chi)無法供(gong)電(dian)且功能(neng)(neng)完全終(zhong)(zhong)止(zhi)。在少數(shu)情況(kuang)下，電(dian)池(chi)有(you)可能(neng)(neng)過熱(re)、熔(rong)斷、著(zhu)火乃(nai)至(zhi)(zhi)爆炸。這就是(shi)近期(qi)所報道(dao)的(de)(de)(de)(de)(de)(de)(de)電(dian)池(chi)故(gu)障(zhang)的(de)(de)(de)(de)(de)(de)(de)主要根(gen)源，并(bing)使(shi)(shi)得(de)眾多的(de)(de)(de)(de)(de)(de)(de)廠(chang)商(shang)不得(de)不將其(qi)產品召回。

電池管理單元（BMS）以及電池保護

      電(dian)(dian)(dian)(dian)池(chi)材料的(de)(de)(de)不斷開發提(ti)升了(le)熱失(shi)控的(de)(de)(de)上限(xian)溫度。另一方面，雖然電(dian)(dian)(dian)(dian)池(chi)必(bi)須通過(guo)嚴格的(de)(de)(de)UL安全測(ce)試，例如(ru)UL1642，但提(ti)供(gong)正確(que)的(de)(de)(de)充電(dian)(dian)(dian)(dian)狀(zhuang)態(tai)并(bing)很好的(de)(de)(de)應對(dui)多種有可(ke)(ke)能(neng)出現的(de)(de)(de)電(dian)(dian)(dian)(dian)子(zi)原件故(gu)障(zhang)仍然是(shi)系統設計人員的(de)(de)(de)職責所在。過(guo)電(dian)(dian)(dian)(dian)壓、過(guo)電(dian)(dian)(dian)(dian)流、短路(lu)、過(guo)熱狀(zhuang)態(tai)以及外(wai)部分立元件的(de)(de)(de)故(gu)障(zhang)都有可(ke)(ke)能(neng)引起電(dian)(dian)(dian)(dian)池(chi)突變的(de)(de)(de)失(shi)效。這就(jiu)意味著需要(yao)采取多重的(de)(de)(de)保(bao)護――在同(tong)一電(dian)(dian)(dian)(dian)池(chi)包內具(ju)有至(zhi)少兩個獨(du)立的(de)(de)(de)保(bao)護電(dian)(dian)(dian)(dian)路(lu)或機制(zhi)。同(tong)時，還希望(wang)具(ju)備用(yong)于檢測(ce)電(dian)(dian)(dian)(dian)池(chi)內部微小短路(lu)的(de)(de)(de)電(dian)(dian)(dian)(dian)子(zi)電(dian)(dian)(dian)(dian)路(lu)以避免(mian)電(dian)(dian)(dian)(dian)池(chi)故(gu)障(zhang)。

     電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)量(liang)(liang)計(ji)(ji)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)路(lu)設計(ji)(ji)用(yong)于精(jing)確的(de)(de)指示可用(yong)的(de)(de)鋰離(li)子(zi)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)量(liang)(liang)。該(gai)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)路(lu)獨特的(de)(de)算法允(yun)許(xu)實時的(de)(de)追蹤電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)包(bao)(bao)的(de)(de)蓄電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)量(liang)(liang)變(bian)化、電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)阻抗(kang)(kang)、電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)、電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流、溫(wen)度(du)(du)以(yi)(yi)(yi)及(ji)(ji)其它電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)路(lu)信息。電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)量(liang)(liang)計(ji)(ji)自(zi)動(dong)的(de)(de)計(ji)(ji)算充電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)及(ji)(ji)放(fang)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)的(de)(de)速率、自(zi)放(fang)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)以(yi)(yi)(yi)及(ji)(ji)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)單(dan)元老化，在電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)使用(yong)壽(shou)命期限內(nei)(nei)實現了高(gao)精(jing)度(du)(du)的(de)(de)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)量(liang)(liang)計(ji)(ji)量(liang)(liang)。例如(ru)，一系列(lie)專利的(de)(de)阻抗(kang)(kang)追蹤電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)量(liang)(liang)計(ji)(ji)，包(bao)(bao)括bq20z70，bq20z80以(yi)(yi)(yi)及(ji)(ji)bq20z90，均可在電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)壽(shou)命期限內(nei)(nei)提供(gong)高(gao)達1%精(jing)度(du)(du)的(de)(de)計(ji)(ji)量(liang)(liang)。單(dan)個熱(re)敏電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)阻被用(yong)于監(jian)測(ce)鋰離(li)子(zi)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)的(de)(de)溫(wen)度(du)(du)，以(yi)(yi)(yi)實現電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)單(dan)元的(de)(de)過(guo)熱(re)保護，并用(yong)于充電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)及(ji)(ji)放(fang)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)限定。例如(ru)，電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)單(dan)元一般不允(yun)許(xu)在低于0℃或高(gao)于45℃的(de)(de)溫(wen)度(du)(du)范圍內(nei)(nei)充電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)，且(qie)不允(yun)許(xu)在電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)單(dan)元溫(wen)度(du)(du)高(gao)于65℃時放(fang)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)。如(ru)檢(jian)測(ce)到過(guo)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)、過(guo)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流或過(guo)熱(re)狀態，電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)量(liang)(liang)計(ji)(ji)IC將指令控制AFE關(guan)閉充電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)及(ji)(ji)放(fang)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)MOSFET Q1及(ji)(ji)Q2。當檢(jian)測(ce)到電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)欠(qian)壓(ya)（under-voltage）狀態時，則(ze)將指令控制AFE關(guan)閉放(fang)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)MOSFET Q2，且(qie)同時保持充電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)MOSFET開啟，以(yi)(yi)(yi)允(yun)許(xu)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)充電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)。

     AFE的(de)主要任務(wu)是對過(guo)載(zai)、短(duan)路的(de)檢(jian)(jian)測(ce)，并保護充(chong)電(dian)(dian)(dian)(dian)及(ji)放電(dian)(dian)(dian)(dian)MOSFET、電(dian)(dian)(dian)(dian)池單元以及(ji)其它線(xian)路上的(de)元件(jian)，避(bi)免過(guo)電(dian)(dian)(dian)(dian)流狀態(tai)(tai)。過(guo)載(zai)檢(jian)(jian)測(ce)用(yong)于檢(jian)(jian)測(ce)電(dian)(dian)(dian)(dian)池放電(dian)(dian)(dian)(dian)流向(xiang)上的(de)過(guo)電(dian)(dian)(dian)(dian)流（OC），同時(shi)，短(duan)路（SC）檢(jian)(jian)測(ce)用(yong)于檢(jian)(jian)測(ce)充(chong)電(dian)(dian)(dian)(dian)及(ji)放電(dian)(dian)(dian)(dian)流向(xiang)上的(de)過(guo)電(dian)(dian)(dian)(dian)流。AFE電(dian)(dian)(dian)(dian)路的(de)過(guo)載(zai)和短(duan)路限定以及(ji)延(yan)遲(chi)時(shi)間(jian)(jian)均(jun)可通過(guo)電(dian)(dian)(dian)(dian)量計(ji)數(shu)據(ju)閃(shan)存編程設定。當檢(jian)(jian)測(ce)到過(guo)載(zai)或短(duan)路狀態(tai)(tai)，且達到了程序(xu)設定的(de)延(yan)遲(chi)時(shi)間(jian)(jian)，則(ze)充(chong)電(dian)(dian)(dian)(dian)及(ji)放電(dian)(dian)(dian)(dian)MOSFET Q1及(ji)Q2將被關閉，詳細的(de)狀態(tai)(tai)信息將存儲(chu)于AFE的(de)狀態(tai)(tai)寄存器，從而電(dian)(dian)(dian)(dian)量計(ji)可讀取并調查導致(zhi)故障的(de)原因。

對于計量2、3或4個鋰離子電池包的(de)(de)(de)(de)(de)(de)(de)電(dian)(dian)(dian)(dian)(dian)量計(ji)芯片集解決方案(an)來(lai)說，AFE起了(le)(le)很重要(yao)的(de)(de)(de)(de)(de)(de)(de)作用(yong)。AFE提供了(le)(le)所需(xu)的(de)(de)(de)(de)(de)(de)(de)所有高壓接(jie)口以(yi)及硬件(jian)電(dian)(dian)(dian)(dian)(dian)流保(bao)護特性(xing)。所提供的(de)(de)(de)(de)(de)(de)(de)I2C兼(jian)容(rong)接(jie)口允(yun)許(xu)電(dian)(dian)(dian)(dian)(dian)量計(ji)訪(fang)問AFE寄存器(qi)并配置(zhi)AFE的(de)(de)(de)(de)(de)(de)(de)保(bao)護特性(xing)。AFE還集成了(le)(le)電(dian)(dian)(dian)(dian)(dian)池單(dan)元(yuan)(yuan)平衡(heng)(heng)控制。多(duo)數(shu)情(qing)況下，在(zai)多(duo)單(dan)元(yuan)(yuan)電(dian)(dian)(dian)(dian)(dian)池包中，每(mei)個獨立電(dian)(dian)(dian)(dian)(dian)池單(dan)元(yuan)(yuan)的(de)(de)(de)(de)(de)(de)(de)電(dian)(dian)(dian)(dian)(dian)荷狀態(tai)（SOC）彼(bi)此不同，從而(er)導致了(le)(le)不平衡(heng)(heng)單(dan)元(yuan)(yuan)間的(de)(de)(de)(de)(de)(de)(de)電(dian)(dian)(dian)(dian)(dian)壓差別(bie)。AFE針對每(mei)一(yi)的(de)(de)(de)(de)(de)(de)(de)電(dian)(dian)(dian)(dian)(dian)池單(dan)元(yuan)(yuan)整(zheng)合了(le)(le)旁(pang)通(tong)(tong)通(tong)(tong)路。此類旁(pang)通(tong)(tong)通(tong)(tong)路可(ke)用(yong)于(yu)降低(di)至每(mei)一(yi)單(dan)元(yuan)(yuan)的(de)(de)(de)(de)(de)(de)(de)充電(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)流，從而(er)為電(dian)(dian)(dian)(dian)(dian)池單(dan)元(yuan)(yuan)充電(dian)(dian)(dian)(dian)(dian)期(qi)間的(de)(de)(de)(de)(de)(de)(de)SOC平衡(heng)(heng)提供了(le)(le)條件(jian)。基于(yu)阻抗(kang)追蹤電(dian)(dian)(dian)(dian)(dian)量計(ji)對每(mei)一(yi)電(dian)(dian)(dian)(dian)(dian)池單(dan)元(yuan)(yuan)化學電(dian)(dian)(dian)(dian)(dian)荷狀態(tai)的(de)(de)(de)(de)(de)(de)(de)確定，可(ke)在(zai)需(xu)要(yao)單(dan)元(yuan)(yuan)平衡(heng)(heng)時做出正確的(de)(de)(de)(de)(de)(de)(de)決策。

       具(ju)(ju)有(you)不同(tong)激活時間(jian)的(de)多(duo)極過電流(liu)保護(hu)限(xian)（如圖2所示）使得(de)電池包(bao)保護(hu)更為強健。電量計具(ju)(ju)有(you)兩層的(de)充電/放電過電流(liu)保護(hu)設定(ding)，而(er)AFE則提供了第三層的(de)放電過電流(liu)保護(hu)。在(zai)短路狀態下，MOSFET及電池可能在(zai)數秒內毀壞，電量計芯(xin)片集(ji)完全依靠AFE來自動的(de)關斷MOSFET，以免產生(sheng)毀壞。

當電量(liang)計(ji)IC及其所關聯(lian)的(de)(de)(de)AFE提(ti)供過電壓(ya)(ya)保(bao)護時(shi)(shi)，電壓(ya)(ya)監(jian)(jian)測(ce)的(de)(de)(de)采(cai)樣特性限(xian)(xian)制(zhi)了此(ci)類保(bao)護系統的(de)(de)(de)響(xiang)應(ying)時(shi)(shi)間。絕大(da)多數應(ying)用要求能快(kuai)速響(xiang)應(ying)，且實(shi)時(shi)(shi)、獨立(li)的(de)(de)(de)過電壓(ya)(ya)監(jian)(jian)測(ce)器，并與(yu)電量(liang)計(ji)、AFE協同運作。該監(jian)(jian)測(ce)器獨立(li)于(yu)電量(liang)計(ji)及AFE，監(jian)(jian)測(ce)每一(yi)電池(chi)單元(yuan)的(de)(de)(de)電壓(ya)(ya)，并針對每一(yi)達到硬件編(bian)碼過電壓(ya)(ya)限(xian)(xian)的(de)(de)(de)電池(chi)單元(yuan)提(ti)供邏(luo)輯電平輸出。過電壓(ya)(ya)保(bao)護的(de)(de)(de)響(xiang)應(ying)時(shi)(shi)間取決(jue)于(yu)外部(bu)延遲電容的(de)(de)(de)大(da)小。在(zai)典(dian)型(xing)的(de)(de)(de)應(ying)用中，秒量(liang)級保(bao)護器的(de)(de)(de)輸出將觸發(fa)化學保(bao)險絲(si)或(huo)其它失效(xiao)保(bao)護設(she)備(bei)，以(yi)永久性的(de)(de)(de)將鋰離(li)子電池(chi)與(yu)系統分離(li)。

電(dian)(dian)(dian)池(chi)包(bao)(bao)永(yong)久性(xing)(xing)的(de)(de)(de)失(shi)(shi)效保護對于(yu)電(dian)(dian)(dian)池(chi)管(guan)理單元(yuan)來說，很(hen)重要的(de)(de)(de)一點是要為(wei)非正常狀態(tai)(tai)下的(de)(de)(de)電(dian)(dian)(dian)池(chi)包(bao)(bao)提供趨于(yu)保守(shou)的(de)(de)(de)關斷。永(yong)久性(xing)(xing)的(de)(de)(de)失(shi)(shi)效保護包(bao)(bao)括了過電(dian)(dian)(dian)流的(de)(de)(de)放電(dian)(dian)(dian)及(ji)(ji)充電(dian)(dian)(dian)故障(zhang)狀態(tai)(tai)下的(de)(de)(de)安(an)全(quan)(quan)、過熱的(de)(de)(de)放電(dian)(dian)(dian)及(ji)(ji)充電(dian)(dian)(dian)狀態(tai)(tai)下的(de)(de)(de)安(an)全(quan)(quan)、過電(dian)(dian)(dian)壓(ya)(ya)的(de)(de)(de)故障(zhang)狀態(tai)(tai)（峰值電(dian)(dian)(dian)壓(ya)(ya)）以及(ji)(ji)電(dian)(dian)(dian)池(chi)平(ping)衡故障(zhang)、短接放電(dian)(dian)(dian)FET故障(zhang)、充電(dian)(dian)(dian)MOSFET故障(zhang)狀態(tai)(tai)下的(de)(de)(de)安(an)全(quan)(quan)。制造商可選(xuan)擇任意(yi)(yi)組合(he)上述的(de)(de)(de)永(yong)久性(xing)(xing)失(shi)(shi)效保護。當檢(jian)測到任意(yi)(yi)的(de)(de)(de)此(ci)類故障(zhang)，則(ze)保護設備將熔斷化(hua)(hua)學(xue)保險絲，以使(shi)得電(dian)(dian)(dian)池(chi)包(bao)(bao)永(yong)久性(xing)(xing)的(de)(de)(de)失(shi)(shi)效。作為(wei)電(dian)(dian)(dian)子元(yuan)件故障(zhang)的(de)(de)(de)外部失(shi)(shi)效驗證(zheng)，電(dian)(dian)(dian)池(chi)管(guan)理單元(yuan)設計用于(yu)檢(jian)測充電(dian)(dian)(dian)及(ji)(ji)放電(dian)(dian)(dian)MOSFET Q1及(ji)(ji)Q2的(de)(de)(de)失(shi)(shi)效與否。如(ru)果任意(yi)(yi)充電(dian)(dian)(dian)或放電(dian)(dian)(dian)MOSFET短路，則(ze)化(hua)(hua)學(xue)保險絲也將熔斷。

      據報道，電(dian)(dian)池(chi)內部(bu)的(de)(de)(de)微小(xiao)(xiao)(xiao)短路(lu)也(ye)是(shi)導(dao)致近期(qi)多起電(dian)(dian)池(chi)召(zhao)回的(de)(de)(de)主要原因。如何檢測電(dian)(dian)池(chi)內部(bu)的(de)(de)(de)微小(xiao)(xiao)(xiao)短路(lu)并防(fang)止(zhi)電(dian)(dian)池(chi)著火乃至(zhi)爆炸(zha)呢？外殼封閉(bi)處(chu)理過(guo)程中，金屬微粒及其它(ta)雜質有(you)可能污染電(dian)(dian)池(chi)內部(bu)，從(cong)(cong)而(er)引起電(dian)(dian)池(chi)內部(bu)的(de)(de)(de)微小(xiao)(xiao)(xiao)短路(lu)。內部(bu)的(de)(de)(de)微小(xiao)(xiao)(xiao)短路(lu)將極(ji)大地增加電(dian)(dian)池(chi)的(de)(de)(de)自放電(dian)(dian)速率(lv)，使得開(kai)路(lu)電(dian)(dian)壓較之正(zheng)常狀態下的(de)(de)(de)電(dian)(dian)池(chi)單(dan)(dan)元有(you)所(suo)降低。阻抗(kang)追(zhui)蹤電(dian)(dian)量計監測開(kai)路(lu)電(dian)(dian)壓，并從(cong)(cong)而(er)檢測電(dian)(dian)池(chi)單(dan)(dan)元的(de)(de)(de)非均衡性(xing)――當不同電(dian)(dian)池(chi)單(dan)(dan)元的(de)(de)(de)開(kai)路(lu)電(dian)(dian)壓差異超過(guo)預先設置的(de)(de)(de)限定值。當出現此類失效時，將產生永(yong)久(jiu)性(xing)失效的(de)(de)(de)告警并斷(duan)開(kai)MOSFET，化學(xue)保險絲(si)也(ye)可配置為熔斷(duan)。上述行為將使得電(dian)(dian)池(chi)包無(wu)法作(zuo)為供電(dian)(dian)源并因此屏蔽了(le)電(dian)(dian)池(chi)包內部(bu)的(de)(de)(de)微小(xiao)(xiao)(xiao)短路(lu)電(dian)(dian)池(chi)單(dan)(dan)元，從(cong)(cong)而(er)防(fang)止(zhi)了(le)災害的(de)(de)(de)發生。

小結

電(dian)(dian)池(chi)(chi)管(guan)理(li)單元對于確保終(zhong)端(duan)用(yong)(yong)戶的(de)(de)安全(quan)性是(shi)至關重要的(de)(de)。強(qiang)健的(de)(de)多極保護――過電(dian)(dian)壓、過電(dian)(dian)流、過熱、電(dian)(dian)池(chi)(chi)單元非均衡以及(ji)MOSFET失(shi)效監(jian)測，極大地改善了(le)電(dian)(dian)池(chi)(chi)包的(de)(de)安全(quan)性。通過監(jian)測電(dian)(dian)池(chi)(chi)單元的(de)(de)開環電(dian)(dian)壓，阻抗追蹤技術(shu)可檢測電(dian)(dian)池(chi)(chi)內部的(de)(de)微小短路(lu)，并進而永(yong)久(jiu)性的(de)(de)失(shi)效電(dian)(dian)池(chi)(chi)，確保了(le)終(zhong)端(duan)用(yong)(yong)戶的(de)(de)安全(quan)。