電(dian)(dian)(dian)(dian)(dian)池(chi)(chi)組制造商來說，針對電(dian)(dian)(dian)(dian)(dian)池(chi)(chi)供(gong)(gong)電(dian)(dian)(dian)(dian)(dian)系統(tong)構(gou)建安全且(qie)可靠(kao)的(de)(de)產品(pin)是至關重要的(de)(de)。電(dian)(dian)(dian)(dian)(dian)池(chi)(chi)包中的(de)(de)電(dian)(dian)(dian)(dian)(dian)池(chi)(chi)管理電(dian)(dian)(dian)(dian)(dian)路(lu)(lu)可以(yi)監控(kong)鋰離子(zi)電(dian)(dian)(dian)(dian)(dian)池(chi)(chi)的(de)(de)運行狀(zhuang)態，包括了電(dian)(dian)(dian)(dian)(dian)池(chi)(chi)阻抗(kang)、溫度(du)、單元(yuan)電(dian)(dian)(dian)(dian)(dian)壓、充電(dian)(dian)(dian)(dian)(dian)和放電(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)流(liu)以(yi)及充電(dian)(dian)(dian)(dian)(dian)狀(zhuang)態等，以(yi)為(wei)系統(tong)提供(gong)(gong)詳(xiang)細的(de)(de)剩(sheng)余運轉(zhuan)時間和電(dian)(dian)(dian)(dian)(dian)池(chi)(chi)健(jian)康(kang)狀(zhuang)況信息，確(que)保(bao)系統(tong)作出正確(que)的(de)(de)決(jue)策。此(ci)外(wai)，為(wei)了改進(jin)電(dian)(dian)(dian)(dian)(dian)池(chi)(chi)的(de)(de)安全性能，即使只(zhi)有一種故障發生，例(li)如過電(dian)(dian)(dian)(dian)(dian)流(liu)、短路(lu)(lu)、單元(yuan)和電(dian)(dian)(dian)(dian)(dian)池(chi)(chi)包的(de)(de)電(dian)(dian)(dian)(dian)(dian)壓過高、溫度(du)過高等，系統(tong)也會關閉(bi)兩個和鋰離子(zi)電(dian)(dian)(dian)(dian)(dian)池(chi)(chi)串聯的(de)(de)背靠(kao)背（back-to-back）保(bao)護MOSFET，將電(dian)(dian)(dian)(dian)(dian)池(chi)(chi)單元(yuan)斷開。基于阻抗(kang)跟蹤技(ji)術的(de)(de)電(dian)(dian)(dian)(dian)(dian)池(chi)(chi)管理單元(yuan)（BMS）會在整個電(dian)(dian)(dian)(dian)(dian)池(chi)(chi)使用周期內監控(kong)單元(yuan)阻抗(kang)和電(dian)(dian)(dian)(dian)(dian)壓失衡(heng)，并有可能檢測電(dian)(dian)(dian)(dian)(dian)池(chi)(chi)的(de)(de)微小短路(lu)(lu)（micro-short），防止(zhi)電(dian)(dian)(dian)(dian)(dian)池(chi)(chi)單元(yuan)造成火災(zai)乃至爆炸(zha)。

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(du)充電期間，活躍得金屬鋰沉(chen)積在電池的(de)正極，其材料極大的(de)增加了爆炸(zha)的(de)危險性，因為鋰將(jiang)有(you)可能與多種材料起反(fan)應而(er)爆炸(zha)，包括了電解(jie)液及陰極材料。例如(ru)，鋰/碳插層混合物（intercalated compound）與水發生反(fan)應，并釋放出氫氣，氫氣有(you)可能被反(fan)應放熱(re)所引燃。陰極材料，諸如(ru)LiCoO2，在溫(wen)度(du)超過175℃的(de)熱(re)失控溫(wen)度(du)限（4.3V單元電壓）時，也將(jiang)開始與電解(jie)液發生反(fan)應。

      鋰(li)離子(zi)(zi)電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)使(shi)(shi)用很薄的(de)(de)(de)微(wei)孔膜（micro-porous film）材(cai)(cai)料(liao)，例(li)如聚(ju)烯(xi)烴，進行電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)正負(fu)極(ji)(ji)(ji)的(de)(de)(de)電(dian)(dian)(dian)(dian)(dian)(dian)子(zi)(zi)隔離，因(yin)為(wei)(wei)此類材(cai)(cai)料(liao)具有卓越的(de)(de)(de)力(li)學(xue)性(xing)能、化(hua)學(xue)穩定性(xing)以及(ji)可(ke)(ke)(ke)接(jie)受的(de)(de)(de)價格。聚(ju)烯(xi)烴的(de)(de)(de)熔點(dian)范圍較低，為(wei)(wei)135℃至 165℃，使(shi)(shi)得(de)聚(ju)烯(xi)烴適用于作(zuo)為(wei)(wei)熱保險（fuse）材(cai)(cai)料(liao)。隨(sui)著(zhu)溫度(du)的(de)(de)(de)升高并(bing)(bing)達到(dao)聚(ju)合體的(de)(de)(de)熔點(dian)，材(cai)(cai)料(liao)的(de)(de)(de)多孔性(xing)將失(shi)效(xiao)，其目的(de)(de)(de)是(shi)使(shi)(shi)得(de)鋰(li)離子(zi)(zi)無法(fa)(fa)在電(dian)(dian)(dian)(dian)(dian)(dian)極(ji)(ji)(ji)之(zhi)間(jian)流動(dong)，從而關斷(duan)電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)。同時，熱敏陶瓷(ci)（PCT）設(she)備以及(ji)安(an)全排出口（safety vent）為(wei)(wei)鋰(li)離子(zi)(zi)電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)提供了額外的(de)(de)(de)保護。電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)的(de)(de)(de)外殼，一般作(zuo)為(wei)(wei)負(fu)極(ji)(ji)(ji)接(jie)線端，通常(chang)為(wei)(wei)典型的(de)(de)(de)鍍鎳金(jin)屬板。在殼體密封的(de)(de)(de)情(qing)(qing)況(kuang)下(xia)(xia)，金(jin)屬微(wei)粒將可(ke)(ke)(ke)能污染電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)的(de)(de)(de)內部。隨(sui)著(zhu)時間(jian)的(de)(de)(de)推移，微(wei)粒有可(ke)(ke)(ke)能遷移至隔離器，并(bing)(bing)使(shi)(shi)得(de)電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)陽(yang)極(ji)(ji)(ji)與(yu)陰極(ji)(ji)(ji)之(zhi)間(jian)的(de)(de)(de)絕緣層老(lao)化(hua)。而陽(yang)極(ji)(ji)(ji)與(yu)陰極(ji)(ji)(ji)之(zhi)間(jian)的(de)(de)(de)微(wei)小短路將允(yun)許電(dian)(dian)(dian)(dian)(dian)(dian)子(zi)(zi)肆意(yi)的(de)(de)(de)流動(dong)，并(bing)(bing)最終使(shi)(shi)電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)失(shi)效(xiao)。絕大多數情(qing)(qing)況(kuang)下(xia)(xia)，此類失(shi)效(xiao)等同于電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)無法(fa)(fa)供電(dian)(dian)(dian)(dian)(dian)(dian)且功能完全終止(zhi)。在少數情(qing)(qing)況(kuang)下(xia)(xia)，電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)有可(ke)(ke)(ke)能過(guo)熱、熔斷(duan)、著(zhu)火(huo)乃至爆炸。這就是(shi)近(jin)期(qi)所(suo)報(bao)道的(de)(de)(de)電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)故障的(de)(de)(de)主要根源，并(bing)(bing)使(shi)(shi)得(de)眾多的(de)(de)(de)廠(chang)商不得(de)不將其產品召回。

電池管理單元（BMS）以及電池保護

      電(dian)池(chi)(chi)材(cai)料的(de)(de)(de)不斷開(kai)發提升了熱(re)失控(kong)的(de)(de)(de)上限溫度。另(ling)一方面，雖然電(dian)池(chi)(chi)必須通(tong)過(guo)嚴格(ge)的(de)(de)(de)UL安全測試，例如(ru)UL1642，但提供正確(que)的(de)(de)(de)充電(dian)狀態(tai)并很(hen)好(hao)的(de)(de)(de)應對多(duo)種有可能(neng)出現的(de)(de)(de)電(dian)子原件故(gu)障(zhang)(zhang)仍然是系(xi)統設計人(ren)員的(de)(de)(de)職責所在。過(guo)電(dian)壓、過(guo)電(dian)流(liu)、短路、過(guo)熱(re)狀態(tai)以及外部分立元件的(de)(de)(de)故(gu)障(zhang)(zhang)都有可能(neng)引(yin)起電(dian)池(chi)(chi)突變的(de)(de)(de)失效。這就(jiu)意(yi)味著需要采取多(duo)重(zhong)的(de)(de)(de)保(bao)護(hu)――在同(tong)一電(dian)池(chi)(chi)包內(nei)具有至少(shao)兩個獨立的(de)(de)(de)保(bao)護(hu)電(dian)路或(huo)機(ji)制(zhi)。同(tong)時(shi)，還(huan)希望具備用于檢測電(dian)池(chi)(chi)內(nei)部微(wei)小短路的(de)(de)(de)電(dian)子電(dian)路以避(bi)免電(dian)池(chi)(chi)故(gu)障(zhang)(zhang)。

     電(dian)(dian)(dian)(dian)(dian)(dian)(dian)量(liang)(liang)計(ji)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)路(lu)設計(ji)用(yong)(yong)于精確的(de)(de)指(zhi)示可用(yong)(yong)的(de)(de)鋰離子(zi)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)量(liang)(liang)。該電(dian)(dian)(dian)(dian)(dian)(dian)(dian)路(lu)獨特的(de)(de)算法允(yun)許(xu)實(shi)時(shi)(shi)的(de)(de)追(zhui)蹤電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)包的(de)(de)蓄(xu)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)量(liang)(liang)變化、電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)阻(zu)抗、電(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)、電(dian)(dian)(dian)(dian)(dian)(dian)(dian)流、溫(wen)度(du)(du)以(yi)及(ji)其它(ta)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)路(lu)信息。電(dian)(dian)(dian)(dian)(dian)(dian)(dian)量(liang)(liang)計(ji)自動(dong)的(de)(de)計(ji)算充電(dian)(dian)(dian)(dian)(dian)(dian)(dian)及(ji)放(fang)(fang)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)的(de)(de)速(su)率、自放(fang)(fang)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)以(yi)及(ji)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)單元(yuan)老化，在(zai)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)使用(yong)(yong)壽命(ming)期(qi)限(xian)內實(shi)現了高(gao)(gao)(gao)精度(du)(du)的(de)(de)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)量(liang)(liang)計(ji)量(liang)(liang)。例(li)如，一系列專利的(de)(de)阻(zu)抗追(zhui)蹤電(dian)(dian)(dian)(dian)(dian)(dian)(dian)量(liang)(liang)計(ji)，包括bq20z70，bq20z80以(yi)及(ji)bq20z90，均(jun)可在(zai)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)壽命(ming)期(qi)限(xian)內提供高(gao)(gao)(gao)達1%精度(du)(du)的(de)(de)計(ji)量(liang)(liang)。單個熱敏電(dian)(dian)(dian)(dian)(dian)(dian)(dian)阻(zu)被用(yong)(yong)于監測(ce)鋰離子(zi)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)的(de)(de)溫(wen)度(du)(du)，以(yi)實(shi)現電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)單元(yuan)的(de)(de)過熱保護(hu)，并用(yong)(yong)于充電(dian)(dian)(dian)(dian)(dian)(dian)(dian)及(ji)放(fang)(fang)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)限(xian)定。例(li)如，電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)單元(yuan)一般不允(yun)許(xu)在(zai)低于0℃或(huo)高(gao)(gao)(gao)于45℃的(de)(de)溫(wen)度(du)(du)范圍(wei)內充電(dian)(dian)(dian)(dian)(dian)(dian)(dian)，且不允(yun)許(xu)在(zai)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)單元(yuan)溫(wen)度(du)(du)高(gao)(gao)(gao)于65℃時(shi)(shi)放(fang)(fang)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)。如檢(jian)測(ce)到過電(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)、過電(dian)(dian)(dian)(dian)(dian)(dian)(dian)流或(huo)過熱狀(zhuang)態(tai)，電(dian)(dian)(dian)(dian)(dian)(dian)(dian)量(liang)(liang)計(ji)IC將(jiang)指(zhi)令控(kong)制AFE關閉(bi)充電(dian)(dian)(dian)(dian)(dian)(dian)(dian)及(ji)放(fang)(fang)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)MOSFET Q1及(ji)Q2。當(dang)檢(jian)測(ce)到電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)欠壓(ya)（under-voltage）狀(zhuang)態(tai)時(shi)(shi)，則將(jiang)指(zhi)令控(kong)制AFE關閉(bi)放(fang)(fang)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)MOSFET Q2，且同時(shi)(shi)保持充電(dian)(dian)(dian)(dian)(dian)(dian)(dian)MOSFET開啟(qi)，以(yi)允(yun)許(xu)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)充電(dian)(dian)(dian)(dian)(dian)(dian)(dian)。

     AFE的(de)(de)(de)主要任務是對過(guo)載(zai)、短(duan)(duan)(duan)路(lu)(lu)的(de)(de)(de)檢測(ce)(ce)，并保(bao)護充電(dian)及(ji)放電(dian)MOSFET、電(dian)池(chi)單元以及(ji)其(qi)它線路(lu)(lu)上的(de)(de)(de)元件，避免過(guo)電(dian)流(liu)狀態(tai)。過(guo)載(zai)檢測(ce)(ce)用于(yu)檢測(ce)(ce)電(dian)池(chi)放電(dian)流(liu)向上的(de)(de)(de)過(guo)電(dian)流(liu)（OC），同時(shi)(shi)，短(duan)(duan)(duan)路(lu)(lu)（SC）檢測(ce)(ce)用于(yu)檢測(ce)(ce)充電(dian)及(ji)放電(dian)流(liu)向上的(de)(de)(de)過(guo)電(dian)流(liu)。AFE電(dian)路(lu)(lu)的(de)(de)(de)過(guo)載(zai)和短(duan)(duan)(duan)路(lu)(lu)限(xian)定以及(ji)延(yan)遲時(shi)(shi)間均可(ke)通過(guo)電(dian)量(liang)計數據閃存(cun)編(bian)程設定。當檢測(ce)(ce)到(dao)過(guo)載(zai)或短(duan)(duan)(duan)路(lu)(lu)狀態(tai)，且達到(dao)了程序設定的(de)(de)(de)延(yan)遲時(shi)(shi)間，則充電(dian)及(ji)放電(dian)MOSFET Q1及(ji)Q2將被關閉(bi)，詳細的(de)(de)(de)狀態(tai)信息將存(cun)儲于(yu)AFE的(de)(de)(de)狀態(tai)寄存(cun)器，從而電(dian)量(liang)計可(ke)讀取并調查導致故(gu)障的(de)(de)(de)原因。

對于計量2、3或4個鋰離子電池包(bao)(bao)的(de)(de)(de)電(dian)(dian)(dian)(dian)(dian)量計(ji)芯片集解(jie)決方案(an)來說(shuo)，AFE起了很(hen)重要的(de)(de)(de)作用。AFE提供了所(suo)需的(de)(de)(de)所(suo)有高壓(ya)接口(kou)以及硬件(jian)電(dian)(dian)(dian)(dian)(dian)流(liu)(liu)保護(hu)特(te)性。所(suo)提供的(de)(de)(de)I2C兼(jian)容接口(kou)允許電(dian)(dian)(dian)(dian)(dian)量計(ji)訪(fang)問AFE寄存(cun)器并配(pei)置(zhi)AFE的(de)(de)(de)保護(hu)特(te)性。AFE還集成了電(dian)(dian)(dian)(dian)(dian)池單(dan)(dan)(dan)元(yuan)(yuan)平衡(heng)控制。多數(shu)情況下，在多單(dan)(dan)(dan)元(yuan)(yuan)電(dian)(dian)(dian)(dian)(dian)池包(bao)(bao)中，每(mei)個獨立電(dian)(dian)(dian)(dian)(dian)池單(dan)(dan)(dan)元(yuan)(yuan)的(de)(de)(de)電(dian)(dian)(dian)(dian)(dian)荷(he)(he)狀態（SOC）彼此不同，從(cong)而導(dao)致了不平衡(heng)單(dan)(dan)(dan)元(yuan)(yuan)間的(de)(de)(de)電(dian)(dian)(dian)(dian)(dian)壓(ya)差別。AFE針對(dui)每(mei)一的(de)(de)(de)電(dian)(dian)(dian)(dian)(dian)池單(dan)(dan)(dan)元(yuan)(yuan)整(zheng)合了旁(pang)通(tong)通(tong)路。此類旁(pang)通(tong)通(tong)路可用于降低至每(mei)一單(dan)(dan)(dan)元(yuan)(yuan)的(de)(de)(de)充電(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)流(liu)(liu)，從(cong)而為電(dian)(dian)(dian)(dian)(dian)池單(dan)(dan)(dan)元(yuan)(yuan)充電(dian)(dian)(dian)(dian)(dian)期間的(de)(de)(de)SOC平衡(heng)提供了條件(jian)。基于阻抗追蹤(zong)電(dian)(dian)(dian)(dian)(dian)量計(ji)對(dui)每(mei)一電(dian)(dian)(dian)(dian)(dian)池單(dan)(dan)(dan)元(yuan)(yuan)化(hua)學(xue)電(dian)(dian)(dian)(dian)(dian)荷(he)(he)狀態的(de)(de)(de)確(que)定，可在需要單(dan)(dan)(dan)元(yuan)(yuan)平衡(heng)時做出正確(que)的(de)(de)(de)決策。

       具有(you)不同(tong)激(ji)活時間(jian)的多極過電(dian)(dian)(dian)流(liu)保(bao)(bao)護限（如(ru)圖2所(suo)示）使得(de)電(dian)(dian)(dian)池包保(bao)(bao)護更為強健。電(dian)(dian)(dian)量計具有(you)兩(liang)層的充電(dian)(dian)(dian)/放(fang)電(dian)(dian)(dian)過電(dian)(dian)(dian)流(liu)保(bao)(bao)護設定，而AFE則提供了(le)第三層的放(fang)電(dian)(dian)(dian)過電(dian)(dian)(dian)流(liu)保(bao)(bao)護。在(zai)(zai)短路(lu)狀(zhuang)態(tai)下，MOSFET及電(dian)(dian)(dian)池可(ke)能在(zai)(zai)數(shu)秒(miao)內毀(hui)壞，電(dian)(dian)(dian)量計芯片集完全(quan)依靠(kao)AFE來自(zi)動的關斷MOSFET，以免(mian)產生毀(hui)壞。

當電(dian)(dian)(dian)(dian)量計(ji)IC及其所關(guan)聯的(de)(de)AFE提供過(guo)電(dian)(dian)(dian)(dian)壓(ya)(ya)保護(hu)時，電(dian)(dian)(dian)(dian)壓(ya)(ya)監(jian)(jian)測(ce)(ce)的(de)(de)采樣特性限制了(le)此類保護(hu)系統(tong)的(de)(de)響應(ying)時間。絕大多數應(ying)用要(yao)求能快速響應(ying)，且實時、獨立(li)的(de)(de)過(guo)電(dian)(dian)(dian)(dian)壓(ya)(ya)監(jian)(jian)測(ce)(ce)器(qi)，并與電(dian)(dian)(dian)(dian)量計(ji)、AFE協同運作。該監(jian)(jian)測(ce)(ce)器(qi)獨立(li)于電(dian)(dian)(dian)(dian)量計(ji)及AFE，監(jian)(jian)測(ce)(ce)每(mei)一電(dian)(dian)(dian)(dian)池(chi)單元的(de)(de)電(dian)(dian)(dian)(dian)壓(ya)(ya)，并針對(dui)每(mei)一達(da)到硬件(jian)編(bian)碼過(guo)電(dian)(dian)(dian)(dian)壓(ya)(ya)限的(de)(de)電(dian)(dian)(dian)(dian)池(chi)單元提供邏輯電(dian)(dian)(dian)(dian)平輸出。過(guo)電(dian)(dian)(dian)(dian)壓(ya)(ya)保護(hu)的(de)(de)響應(ying)時間取決于外部延遲電(dian)(dian)(dian)(dian)容的(de)(de)大小。在(zai)典型的(de)(de)應(ying)用中，秒量級保護(hu)器(qi)的(de)(de)輸出將觸發化(hua)學保險絲或其它失效保護(hu)設(she)備，以永(yong)久性的(de)(de)將鋰離子電(dian)(dian)(dian)(dian)池(chi)與系統(tong)分離。

電(dian)(dian)池(chi)包永(yong)(yong)久(jiu)性(xing)(xing)的(de)(de)(de)失(shi)(shi)效(xiao)保(bao)(bao)(bao)護對于電(dian)(dian)池(chi)管理(li)單(dan)元(yuan)(yuan)來說，很(hen)重(zhong)要的(de)(de)(de)一點(dian)是要為非正常狀態(tai)下(xia)(xia)的(de)(de)(de)電(dian)(dian)池(chi)包提供趨(qu)于保(bao)(bao)(bao)守的(de)(de)(de)關斷。永(yong)(yong)久(jiu)性(xing)(xing)的(de)(de)(de)失(shi)(shi)效(xiao)保(bao)(bao)(bao)護包括了過電(dian)(dian)流(liu)的(de)(de)(de)放電(dian)(dian)及(ji)充(chong)(chong)(chong)電(dian)(dian)故(gu)障(zhang)(zhang)狀態(tai)下(xia)(xia)的(de)(de)(de)安(an)全(quan)(quan)、過熱的(de)(de)(de)放電(dian)(dian)及(ji)充(chong)(chong)(chong)電(dian)(dian)狀態(tai)下(xia)(xia)的(de)(de)(de)安(an)全(quan)(quan)、過電(dian)(dian)壓的(de)(de)(de)故(gu)障(zhang)(zhang)狀態(tai)（峰值電(dian)(dian)壓）以及(ji)電(dian)(dian)池(chi)平衡故(gu)障(zhang)(zhang)、短(duan)(duan)接放電(dian)(dian)FET故(gu)障(zhang)(zhang)、充(chong)(chong)(chong)電(dian)(dian)MOSFET故(gu)障(zhang)(zhang)狀態(tai)下(xia)(xia)的(de)(de)(de)安(an)全(quan)(quan)。制造商可選擇任(ren)意組合上述的(de)(de)(de)永(yong)(yong)久(jiu)性(xing)(xing)失(shi)(shi)效(xiao)保(bao)(bao)(bao)護。當檢(jian)測到(dao)任(ren)意的(de)(de)(de)此類(lei)故(gu)障(zhang)(zhang)，則保(bao)(bao)(bao)護設(she)備將熔(rong)斷化(hua)學保(bao)(bao)(bao)險(xian)絲，以使得電(dian)(dian)池(chi)包永(yong)(yong)久(jiu)性(xing)(xing)的(de)(de)(de)失(shi)(shi)效(xiao)。作(zuo)為電(dian)(dian)子元(yuan)(yuan)件故(gu)障(zhang)(zhang)的(de)(de)(de)外(wai)部失(shi)(shi)效(xiao)驗證(zheng)，電(dian)(dian)池(chi)管理(li)單(dan)元(yuan)(yuan)設(she)計用于檢(jian)測充(chong)(chong)(chong)電(dian)(dian)及(ji)放電(dian)(dian)MOSFET Q1及(ji)Q2的(de)(de)(de)失(shi)(shi)效(xiao)與否。如果任(ren)意充(chong)(chong)(chong)電(dian)(dian)或放電(dian)(dian)MOSFET短(duan)(duan)路，則化(hua)學保(bao)(bao)(bao)險(xian)絲也將熔(rong)斷。

      據(ju)報道，電(dian)(dian)(dian)(dian)池(chi)(chi)內部(bu)(bu)(bu)的微(wei)(wei)小(xiao)(xiao)短(duan)(duan)(duan)路(lu)也是導致近期多起電(dian)(dian)(dian)(dian)池(chi)(chi)召回的主要原因(yin)。如何檢測電(dian)(dian)(dian)(dian)池(chi)(chi)內部(bu)(bu)(bu)的微(wei)(wei)小(xiao)(xiao)短(duan)(duan)(duan)路(lu)并防止電(dian)(dian)(dian)(dian)池(chi)(chi)著火乃至爆炸呢？外(wai)殼封閉處理過程中，金屬微(wei)(wei)粒及其(qi)它雜質有可(ke)能污染(ran)電(dian)(dian)(dian)(dian)池(chi)(chi)內部(bu)(bu)(bu)，從(cong)而(er)引起電(dian)(dian)(dian)(dian)池(chi)(chi)內部(bu)(bu)(bu)的微(wei)(wei)小(xiao)(xiao)短(duan)(duan)(duan)路(lu)。內部(bu)(bu)(bu)的微(wei)(wei)小(xiao)(xiao)短(duan)(duan)(duan)路(lu)將(jiang)(jiang)極大(da)地增加電(dian)(dian)(dian)(dian)池(chi)(chi)的自放(fang)電(dian)(dian)(dian)(dian)速率(lv)，使得開(kai)路(lu)電(dian)(dian)(dian)(dian)壓較之(zhi)正常狀態下(xia)的電(dian)(dian)(dian)(dian)池(chi)(chi)單元(yuan)有所降低。阻抗追蹤電(dian)(dian)(dian)(dian)量計監(jian)測開(kai)路(lu)電(dian)(dian)(dian)(dian)壓，并從(cong)而(er)檢測電(dian)(dian)(dian)(dian)池(chi)(chi)單元(yuan)的非(fei)均(jun)衡性――當不(bu)同電(dian)(dian)(dian)(dian)池(chi)(chi)單元(yuan)的開(kai)路(lu)電(dian)(dian)(dian)(dian)壓差異超過預(yu)先設置的限定(ding)值。當出現此(ci)類失(shi)效時，將(jiang)(jiang)產生永久性失(shi)效的告警并斷開(kai)MOSFET，化學保險絲也可(ke)配置為熔斷。上述行為將(jiang)(jiang)使得電(dian)(dian)(dian)(dian)池(chi)(chi)包無法作為供電(dian)(dian)(dian)(dian)源(yuan)并因(yin)此(ci)屏蔽了(le)電(dian)(dian)(dian)(dian)池(chi)(chi)包內部(bu)(bu)(bu)的微(wei)(wei)小(xiao)(xiao)短(duan)(duan)(duan)路(lu)電(dian)(dian)(dian)(dian)池(chi)(chi)單元(yuan)，從(cong)而(er)防止了(le)災害的發生。

小結

電(dian)池(chi)(chi)管(guan)理單元對于確保(bao)(bao)終端用戶的(de)(de)(de)安(an)全(quan)性是至關(guan)重要的(de)(de)(de)。強健的(de)(de)(de)多極保(bao)(bao)護――過(guo)電(dian)壓、過(guo)電(dian)流、過(guo)熱(re)、電(dian)池(chi)(chi)單元非均衡以及MOSFET失效監(jian)測，極大(da)地改善了電(dian)池(chi)(chi)包的(de)(de)(de)安(an)全(quan)性。通(tong)過(guo)監(jian)測電(dian)池(chi)(chi)單元的(de)(de)(de)開環電(dian)壓，阻抗追蹤技術可檢測電(dian)池(chi)(chi)內部的(de)(de)(de)微小(xiao)短路，并進而(er)永久性的(de)(de)(de)失效電(dian)池(chi)(chi)，確保(bao)(bao)了終端用戶的(de)(de)(de)安(an)全(quan)。