電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)組制造商來說，針(zhen)對(dui)電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)供(gong)電(dian)(dian)(dian)(dian)(dian)(dian)系(xi)統(tong)構建安全且可(ke)(ke)靠(kao)的(de)(de)產品是(shi)至關重要的(de)(de)。電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)包中(zhong)的(de)(de)電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)管理(li)電(dian)(dian)(dian)(dian)(dian)(dian)路可(ke)(ke)以(yi)監控(kong)(kong)鋰離(li)子電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)的(de)(de)運行狀態(tai)，包括了(le)電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)阻(zu)(zu)抗(kang)、溫度、單(dan)(dan)元電(dian)(dian)(dian)(dian)(dian)(dian)壓、充電(dian)(dian)(dian)(dian)(dian)(dian)和放電(dian)(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)(dian)流(liu)(liu)以(yi)及充電(dian)(dian)(dian)(dian)(dian)(dian)狀態(tai)等，以(yi)為(wei)系(xi)統(tong)提供(gong)詳細的(de)(de)剩余運轉時間(jian)和電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)健康狀況信息，確(que)保(bao)系(xi)統(tong)作出正確(que)的(de)(de)決策(ce)。此外，為(wei)了(le)改進電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)的(de)(de)安全性能(neng)，即使(shi)只有一種(zhong)故障發生(sheng)，例如過(guo)電(dian)(dian)(dian)(dian)(dian)(dian)流(liu)(liu)、短路、單(dan)(dan)元和電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)包的(de)(de)電(dian)(dian)(dian)(dian)(dian)(dian)壓過(guo)高、溫度過(guo)高等，系(xi)統(tong)也(ye)會(hui)關閉兩個(ge)和鋰離(li)子電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)串聯的(de)(de)背(bei)靠(kao)背(bei)（back-to-back）保(bao)護MOSFET，將電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)單(dan)(dan)元斷開(kai)。基于阻(zu)(zu)抗(kang)跟蹤技術(shu)的(de)(de)電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)管理(li)單(dan)(dan)元（BMS）會(hui)在整個(ge)電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)使(shi)用周期內監控(kong)(kong)單(dan)(dan)元阻(zu)(zu)抗(kang)和電(dian)(dian)(dian)(dian)(dian)(dian)壓失衡，并有可(ke)(ke)能(neng)檢測電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)的(de)(de)微(wei)小短路（micro-short），防止電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)單(dan)(dan)元造成火災乃至爆炸(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(guo)度充電期間，活躍得(de)金屬鋰(li)沉積在電池的(de)正極，其材(cai)料極大的(de)增(zeng)加(jia)了爆(bao)炸(zha)(zha)的(de)危險性，因為鋰(li)將(jiang)有可能(neng)與(yu)多種材(cai)料起(qi)反(fan)應(ying)而爆(bao)炸(zha)(zha)，包括了電解(jie)液(ye)(ye)及陰極材(cai)料。例如(ru)，鋰(li)/碳插層混合物（intercalated compound）與(yu)水(shui)發生(sheng)反(fan)應(ying)，并釋(shi)放出(chu)氫(qing)氣，氫(qing)氣有可能(neng)被反(fan)應(ying)放熱所引燃。陰極材(cai)料，諸如(ru)LiCoO2，在溫度超過(guo)175℃的(de)熱失控溫度限（4.3V單元電壓）時(shi)，也將(jiang)開始與(yu)電解(jie)液(ye)(ye)發生(sheng)反(fan)應(ying)。

      鋰離(li)子電(dian)池(chi)(chi)(chi)(chi)(chi)(chi)使用很薄的(de)(de)(de)微孔(kong)膜(mo)（micro-porous film）材(cai)(cai)(cai)料(liao)，例(li)如聚(ju)(ju)烯(xi)(xi)烴，進(jin)行電(dian)池(chi)(chi)(chi)(chi)(chi)(chi)正負(fu)極的(de)(de)(de)電(dian)子隔離(li)，因(yin)為此(ci)(ci)類材(cai)(cai)(cai)料(liao)具有(you)卓越(yue)的(de)(de)(de)力學(xue)性能(neng)、化(hua)學(xue)穩定性以(yi)及可(ke)接(jie)受的(de)(de)(de)價格。聚(ju)(ju)烯(xi)(xi)烴的(de)(de)(de)熔點(dian)范圍較低，為135℃至 165℃，使得聚(ju)(ju)烯(xi)(xi)烴適用于作為熱保險（fuse）材(cai)(cai)(cai)料(liao)。隨著(zhu)溫度的(de)(de)(de)升高并達到聚(ju)(ju)合體的(de)(de)(de)熔點(dian)，材(cai)(cai)(cai)料(liao)的(de)(de)(de)多(duo)孔(kong)性將(jiang)失效(xiao)，其(qi)目的(de)(de)(de)是使得鋰離(li)子無法在(zai)電(dian)極之間(jian)流動，從(cong)而關斷(duan)電(dian)池(chi)(chi)(chi)(chi)(chi)(chi)。同時，熱敏陶瓷(ci)（PCT）設(she)備以(yi)及安全排出口（safety vent）為鋰離(li)子電(dian)池(chi)(chi)(chi)(chi)(chi)(chi)提供了額外的(de)(de)(de)保護。電(dian)池(chi)(chi)(chi)(chi)(chi)(chi)的(de)(de)(de)外殼，一般(ban)作為負(fu)極接(jie)線端，通常為典型的(de)(de)(de)鍍鎳(nie)金屬板(ban)。在(zai)殼體密(mi)封的(de)(de)(de)情(qing)況下(xia)(xia)，金屬微粒(li)將(jiang)可(ke)能(neng)污染電(dian)池(chi)(chi)(chi)(chi)(chi)(chi)的(de)(de)(de)內(nei)部(bu)。隨著(zhu)時間(jian)的(de)(de)(de)推移(yi)，微粒(li)有(you)可(ke)能(neng)遷(qian)移(yi)至隔離(li)器，并使得電(dian)池(chi)(chi)(chi)(chi)(chi)(chi)陽(yang)極與陰(yin)極之間(jian)的(de)(de)(de)絕緣層老化(hua)。而陽(yang)極與陰(yin)極之間(jian)的(de)(de)(de)微小短路將(jiang)允(yun)許電(dian)子肆意(yi)的(de)(de)(de)流動，并最終(zhong)使電(dian)池(chi)(chi)(chi)(chi)(chi)(chi)失效(xiao)。絕大多(duo)數情(qing)況下(xia)(xia)，此(ci)(ci)類失效(xiao)等同于電(dian)池(chi)(chi)(chi)(chi)(chi)(chi)無法供電(dian)且(qie)功能(neng)完全終(zhong)止。在(zai)少數情(qing)況下(xia)(xia)，電(dian)池(chi)(chi)(chi)(chi)(chi)(chi)有(you)可(ke)能(neng)過熱、熔斷(duan)、著(zhu)火乃至爆炸。這就是近期所報道的(de)(de)(de)電(dian)池(chi)(chi)(chi)(chi)(chi)(chi)故障的(de)(de)(de)主要根源，并使得眾多(duo)的(de)(de)(de)廠商不得不將(jiang)其(qi)產(chan)品(pin)召回。

電池管理單元（BMS）以及電池保護

      電(dian)(dian)(dian)池材料(liao)的(de)(de)(de)不斷開發提升了(le)熱(re)失控的(de)(de)(de)上限溫度。另(ling)一方面，雖然電(dian)(dian)(dian)池必(bi)須通過嚴格的(de)(de)(de)UL安全測(ce)(ce)試，例(li)如UL1642，但(dan)提供正確的(de)(de)(de)充電(dian)(dian)(dian)狀態并很好的(de)(de)(de)應(ying)對(dui)多種有(you)可(ke)能(neng)出現(xian)的(de)(de)(de)電(dian)(dian)(dian)子原件故(gu)(gu)障(zhang)仍然是系統(tong)設(she)計人員(yuan)的(de)(de)(de)職責所在。過電(dian)(dian)(dian)壓、過電(dian)(dian)(dian)流、短路、過熱(re)狀態以及外部分立(li)元件的(de)(de)(de)故(gu)(gu)障(zhang)都有(you)可(ke)能(neng)引起(qi)電(dian)(dian)(dian)池突變(bian)的(de)(de)(de)失效(xiao)。這就(jiu)意味著需要采(cai)取多重的(de)(de)(de)保護――在同一電(dian)(dian)(dian)池包內具有(you)至(zhi)少兩個獨立(li)的(de)(de)(de)保護電(dian)(dian)(dian)路或機制。同時(shi)，還(huan)希望具備用于檢(jian)測(ce)(ce)電(dian)(dian)(dian)池內部微小短路的(de)(de)(de)電(dian)(dian)(dian)子電(dian)(dian)(dian)路以避免電(dian)(dian)(dian)池故(gu)(gu)障(zhang)。

     電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)量(liang)(liang)計(ji)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)路設計(ji)用(yong)(yong)于精確(que)的(de)(de)指(zhi)示可用(yong)(yong)的(de)(de)鋰離子電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)量(liang)(liang)。該電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)路獨特的(de)(de)算(suan)法允(yun)許實(shi)(shi)時(shi)的(de)(de)追(zhui)蹤電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)包(bao)的(de)(de)蓄電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)量(liang)(liang)變化、電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)阻抗、電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓、電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流、溫度以及(ji)(ji)其它電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)路信息。電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)量(liang)(liang)計(ji)自動的(de)(de)計(ji)算(suan)充電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)及(ji)(ji)放(fang)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)的(de)(de)速率、自放(fang)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)以及(ji)(ji)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(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)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)使用(yong)(yong)壽(shou)命(ming)期(qi)限內(nei)實(shi)(shi)現(xian)了高精度的(de)(de)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)量(liang)(liang)計(ji)量(liang)(liang)。例如，一系列專利的(de)(de)阻抗追(zhui)蹤電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)量(liang)(liang)計(ji)，包(bao)括bq20z70，bq20z80以及(ji)(ji)bq20z90，均可在電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)壽(shou)命(ming)期(qi)限內(nei)提(ti)供高達1%精度的(de)(de)計(ji)量(liang)(liang)。單(dan)個熱敏(min)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)阻被(bei)用(yong)(yong)于監測鋰離子電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)的(de)(de)溫度，以實(shi)(shi)現(xian)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)單(dan)元的(de)(de)過(guo)熱保護，并用(yong)(yong)于充電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)及(ji)(ji)放(fang)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)限定。例如，電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)單(dan)元一般不允(yun)許在低于0℃或高于45℃的(de)(de)溫度范圍內(nei)充電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)，且不允(yun)許在電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)單(dan)元溫度高于65℃時(shi)放(fang)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)。如檢測到過(guo)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓、過(guo)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流或過(guo)熱狀態，電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)量(liang)(liang)計(ji)IC將指(zhi)令控(kong)制(zhi)AFE關閉充電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)及(ji)(ji)放(fang)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)MOSFET Q1及(ji)(ji)Q2。當檢測到電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)欠(qian)壓（under-voltage）狀態時(shi)，則將指(zhi)令控(kong)制(zhi)AFE關閉放(fang)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)MOSFET Q2，且同時(shi)保持(chi)充電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)MOSFET開啟，以允(yun)許電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)充電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)。

     AFE的(de)主(zhu)要任務是對過(guo)載(zai)(zai)、短(duan)路的(de)檢(jian)測(ce)(ce)，并(bing)保護充電(dian)(dian)(dian)及(ji)(ji)放電(dian)(dian)(dian)MOSFET、電(dian)(dian)(dian)池單元以(yi)及(ji)(ji)其它線路上的(de)元件，避免過(guo)電(dian)(dian)(dian)流(liu)狀態(tai)。過(guo)載(zai)(zai)檢(jian)測(ce)(ce)用于檢(jian)測(ce)(ce)電(dian)(dian)(dian)池放電(dian)(dian)(dian)流(liu)向上的(de)過(guo)電(dian)(dian)(dian)流(liu)（OC），同時(shi)，短(duan)路（SC）檢(jian)測(ce)(ce)用于檢(jian)測(ce)(ce)充電(dian)(dian)(dian)及(ji)(ji)放電(dian)(dian)(dian)流(liu)向上的(de)過(guo)電(dian)(dian)(dian)流(liu)。AFE電(dian)(dian)(dian)路的(de)過(guo)載(zai)(zai)和短(duan)路限定以(yi)及(ji)(ji)延遲時(shi)間均可通過(guo)電(dian)(dian)(dian)量計(ji)數(shu)據閃存(cun)編程設(she)(she)定。當檢(jian)測(ce)(ce)到(dao)(dao)過(guo)載(zai)(zai)或(huo)短(duan)路狀態(tai)，且(qie)達(da)到(dao)(dao)了程序設(she)(she)定的(de)延遲時(shi)間，則充電(dian)(dian)(dian)及(ji)(ji)放電(dian)(dian)(dian)MOSFET Q1及(ji)(ji)Q2將(jiang)(jiang)被關閉，詳細的(de)狀態(tai)信息將(jiang)(jiang)存(cun)儲于AFE的(de)狀態(tai)寄存(cun)器，從(cong)而電(dian)(dian)(dian)量計(ji)可讀取并(bing)調查(cha)導(dao)致故障的(de)原因。

對于計量2、3或4個鋰離子電池包的(de)電(dian)(dian)(dian)量計芯(xin)片(pian)集解決(jue)方(fang)案來說，AFE起了(le)(le)很重要的(de)作用。AFE提供了(le)(le)所(suo)需的(de)所(suo)有高(gao)壓(ya)接口(kou)以及硬(ying)件電(dian)(dian)(dian)流保(bao)護(hu)特性(xing)。所(suo)提供的(de)I2C兼容接口(kou)允許(xu)電(dian)(dian)(dian)量計訪問(wen)AFE寄存器(qi)并配置(zhi)AFE的(de)保(bao)護(hu)特性(xing)。AFE還集成了(le)(le)電(dian)(dian)(dian)池(chi)(chi)單元(yuan)(yuan)平衡(heng)控(kong)制。多數情(qing)況下，在多單元(yuan)(yuan)電(dian)(dian)(dian)池(chi)(chi)包中，每(mei)個獨立(li)電(dian)(dian)(dian)池(chi)(chi)單元(yuan)(yuan)的(de)電(dian)(dian)(dian)荷狀態(tai)（SOC）彼(bi)此不同(tong)，從而導致(zhi)了(le)(le)不平衡(heng)單元(yuan)(yuan)間(jian)的(de)電(dian)(dian)(dian)壓(ya)差別。AFE針對每(mei)一(yi)的(de)電(dian)(dian)(dian)池(chi)(chi)單元(yuan)(yuan)整(zheng)合了(le)(le)旁通(tong)通(tong)路。此類旁通(tong)通(tong)路可用于(yu)降低(di)至每(mei)一(yi)單元(yuan)(yuan)的(de)充(chong)電(dian)(dian)(dian)電(dian)(dian)(dian)流，從而為電(dian)(dian)(dian)池(chi)(chi)單元(yuan)(yuan)充(chong)電(dian)(dian)(dian)期間(jian)的(de)SOC平衡(heng)提供了(le)(le)條件。基于(yu)阻(zu)抗追(zhui)蹤電(dian)(dian)(dian)量計對每(mei)一(yi)電(dian)(dian)(dian)池(chi)(chi)單元(yuan)(yuan)化學(xue)電(dian)(dian)(dian)荷狀態(tai)的(de)確(que)定，可在需要單元(yuan)(yuan)平衡(heng)時做出正(zheng)確(que)的(de)決(jue)策。

       具有不(bu)同激活時間的(de)(de)多(duo)極過電流保(bao)(bao)護(hu)限(xian)（如圖(tu)2所示）使得電池(chi)包保(bao)(bao)護(hu)更(geng)為強健。電量計具有兩層(ceng)的(de)(de)充電/放電過電流保(bao)(bao)護(hu)設(she)定(ding)，而(er)AFE則提(ti)供了第三層(ceng)的(de)(de)放電過電流保(bao)(bao)護(hu)。在短(duan)路狀態下，MOSFET及電池(chi)可能(neng)在數秒內毀壞，電量計芯片集完(wan)全依(yi)靠AFE來自動的(de)(de)關斷MOSFET，以免產(chan)生毀壞。

當(dang)電(dian)(dian)(dian)量(liang)(liang)(liang)計(ji)IC及(ji)其所關聯(lian)的(de)(de)AFE提供(gong)過電(dian)(dian)(dian)壓(ya)(ya)保(bao)護(hu)(hu)(hu)時，電(dian)(dian)(dian)壓(ya)(ya)監測的(de)(de)采樣特(te)性限制了(le)此類保(bao)護(hu)(hu)(hu)系(xi)統的(de)(de)響(xiang)應(ying)時間(jian)。絕大多數(shu)應(ying)用(yong)要求(qiu)能快速響(xiang)應(ying)，且實時、獨(du)立的(de)(de)過電(dian)(dian)(dian)壓(ya)(ya)監測器，并與(yu)電(dian)(dian)(dian)量(liang)(liang)(liang)計(ji)、AFE協同(tong)運作。該監測器獨(du)立于(yu)電(dian)(dian)(dian)量(liang)(liang)(liang)計(ji)及(ji)AFE，監測每(mei)一電(dian)(dian)(dian)池單元(yuan)的(de)(de)電(dian)(dian)(dian)壓(ya)(ya)，并針對每(mei)一達到硬件編碼過電(dian)(dian)(dian)壓(ya)(ya)限的(de)(de)電(dian)(dian)(dian)池單元(yuan)提供(gong)邏輯電(dian)(dian)(dian)平(ping)輸出。過電(dian)(dian)(dian)壓(ya)(ya)保(bao)護(hu)(hu)(hu)的(de)(de)響(xiang)應(ying)時間(jian)取決于(yu)外部延遲電(dian)(dian)(dian)容的(de)(de)大小。在(zai)典型的(de)(de)應(ying)用(yong)中，秒量(liang)(liang)(liang)級保(bao)護(hu)(hu)(hu)器的(de)(de)輸出將觸發(fa)化學保(bao)險絲(si)或其它失效保(bao)護(hu)(hu)(hu)設(she)備，以永久性的(de)(de)將鋰(li)離子電(dian)(dian)(dian)池與(yu)系(xi)統分離。

電(dian)(dian)(dian)池包永久性(xing)(xing)(xing)的(de)(de)(de)失(shi)效(xiao)保護對于電(dian)(dian)(dian)池管(guan)理單元來說，很(hen)重要的(de)(de)(de)一點是要為(wei)非正常狀態(tai)下的(de)(de)(de)電(dian)(dian)(dian)池包提供趨(qu)于保守的(de)(de)(de)關斷(duan)。永久性(xing)(xing)(xing)的(de)(de)(de)失(shi)效(xiao)保護包括了(le)過(guo)電(dian)(dian)(dian)流的(de)(de)(de)放(fang)電(dian)(dian)(dian)及(ji)(ji)(ji)充(chong)(chong)電(dian)(dian)(dian)故障(zhang)(zhang)狀態(tai)下的(de)(de)(de)安全(quan)、過(guo)熱(re)的(de)(de)(de)放(fang)電(dian)(dian)(dian)及(ji)(ji)(ji)充(chong)(chong)電(dian)(dian)(dian)狀態(tai)下的(de)(de)(de)安全(quan)、過(guo)電(dian)(dian)(dian)壓的(de)(de)(de)故障(zhang)(zhang)狀態(tai)（峰值電(dian)(dian)(dian)壓）以(yi)(yi)及(ji)(ji)(ji)電(dian)(dian)(dian)池平(ping)衡故障(zhang)(zhang)、短接(jie)放(fang)電(dian)(dian)(dian)FET故障(zhang)(zhang)、充(chong)(chong)電(dian)(dian)(dian)MOSFET故障(zhang)(zhang)狀態(tai)下的(de)(de)(de)安全(quan)。制造(zao)商(shang)可選擇任意(yi)組合(he)上述的(de)(de)(de)永久性(xing)(xing)(xing)失(shi)效(xiao)保護。當檢測(ce)到任意(yi)的(de)(de)(de)此類故障(zhang)(zhang)，則(ze)保護設備(bei)將熔斷(duan)化學保險絲，以(yi)(yi)使得電(dian)(dian)(dian)池包永久性(xing)(xing)(xing)的(de)(de)(de)失(shi)效(xiao)。作(zuo)為(wei)電(dian)(dian)(dian)子元件故障(zhang)(zhang)的(de)(de)(de)外部失(shi)效(xiao)驗證，電(dian)(dian)(dian)池管(guan)理單元設計(ji)用于檢測(ce)充(chong)(chong)電(dian)(dian)(dian)及(ji)(ji)(ji)放(fang)電(dian)(dian)(dian)MOSFET Q1及(ji)(ji)(ji)Q2的(de)(de)(de)失(shi)效(xiao)與否。如果任意(yi)充(chong)(chong)電(dian)(dian)(dian)或放(fang)電(dian)(dian)(dian)MOSFET短路，則(ze)化學保險絲也將熔斷(duan)。

      據(ju)報道，電(dian)(dian)池(chi)(chi)內部(bu)的(de)(de)微小(xiao)(xiao)短(duan)路(lu)(lu)也是導致近(jin)期(qi)多起(qi)電(dian)(dian)池(chi)(chi)召回的(de)(de)主要原(yuan)因。如何檢測電(dian)(dian)池(chi)(chi)內部(bu)的(de)(de)微小(xiao)(xiao)短(duan)路(lu)(lu)并防(fang)(fang)止(zhi)電(dian)(dian)池(chi)(chi)著(zhu)火乃至爆炸(zha)呢？外殼(ke)封閉(bi)處理過(guo)程中(zhong)，金(jin)屬微粒及其它雜(za)質(zhi)有(you)可能污染(ran)電(dian)(dian)池(chi)(chi)內部(bu)，從而引起(qi)電(dian)(dian)池(chi)(chi)內部(bu)的(de)(de)微小(xiao)(xiao)短(duan)路(lu)(lu)。內部(bu)的(de)(de)微小(xiao)(xiao)短(duan)路(lu)(lu)將(jiang)(jiang)極大(da)地增加電(dian)(dian)池(chi)(chi)的(de)(de)自(zi)放(fang)電(dian)(dian)速(su)率，使得(de)開路(lu)(lu)電(dian)(dian)壓(ya)較之正常(chang)狀態下的(de)(de)電(dian)(dian)池(chi)(chi)單(dan)元有(you)所(suo)降低。阻抗追蹤(zong)電(dian)(dian)量計(ji)監測開路(lu)(lu)電(dian)(dian)壓(ya)，并從而檢測電(dian)(dian)池(chi)(chi)單(dan)元的(de)(de)非均衡性――當(dang)不同電(dian)(dian)池(chi)(chi)單(dan)元的(de)(de)開路(lu)(lu)電(dian)(dian)壓(ya)差異超(chao)過(guo)預先設置(zhi)的(de)(de)限定值。當(dang)出現此(ci)(ci)類失(shi)效(xiao)時(shi)，將(jiang)(jiang)產生永(yong)久性失(shi)效(xiao)的(de)(de)告警并斷(duan)開MOSFET，化學保險絲(si)也可配置(zhi)為熔斷(duan)。上述(shu)行為將(jiang)(jiang)使得(de)電(dian)(dian)池(chi)(chi)包(bao)無法作為供電(dian)(dian)源并因此(ci)(ci)屏蔽了(le)電(dian)(dian)池(chi)(chi)包(bao)內部(bu)的(de)(de)微小(xiao)(xiao)短(duan)路(lu)(lu)電(dian)(dian)池(chi)(chi)單(dan)元，從而防(fang)(fang)止(zhi)了(le)災害的(de)(de)發生。

小結

電(dian)(dian)池管理單元對于確(que)保終(zhong)端(duan)用戶(hu)(hu)的(de)安全性(xing)是至(zhi)關重(zhong)要的(de)。強健(jian)的(de)多極保護(hu)――過(guo)電(dian)(dian)壓(ya)(ya)、過(guo)電(dian)(dian)流(liu)、過(guo)熱、電(dian)(dian)池單元非均(jun)衡(heng)以及MOSFET失效監測(ce)(ce)，極大地改善(shan)了(le)電(dian)(dian)池包的(de)安全性(xing)。通(tong)過(guo)監測(ce)(ce)電(dian)(dian)池單元的(de)開環電(dian)(dian)壓(ya)(ya)，阻(zu)抗追蹤技術(shu)可檢測(ce)(ce)電(dian)(dian)池內(nei)部的(de)微小短路，并進(jin)而(er)永久性(xing)的(de)失效電(dian)(dian)池，確(que)保了(le)終(zhong)端(duan)用戶(hu)(hu)的(de)安全。