摘要：本應用筆記(ji)簡單介紹了鎳(nie)鎘(NiCd)、鎳(nie)氫(NiMH)和(he)(he)鋰(li)離子(Li-Ion，Li+)可充電電池(chi)(chi),討(tao)論它(ta)們的性能，并(bing)說明(ming)在不需要微控制器的情況(kuang)下如(ru)何構(gou)建單機結構(gou)，安全、快速地為鎳(nie)氫和(he)(he)鋰(li)離子電池(chi)(chi)充電。

車載充電器摘要(yao)：本應用筆記簡單介紹了鎳(nie)(nie)鎘(NiCd)、鎳(nie)(nie)氫(NiMH)和鋰離子(zi)(Li-Ion，Li+)可充(chong)電(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)池,討(tao)論它們的(de)(de)(de)(de)性能(neng)(neng)，并說(shuo)明在(zai)不需要(yao)微控制器的(de)(de)(de)(de)情(qing)況(kuang)下如何構建單機(ji)結構，安全、快速地為鎳(nie)(nie)氫和鋰離子(zi)電(dian)(dian)(dian)(dian)(dian)池充(chong)電(dian)(dian)(dian)(dian)(dian)。概述(shu)充(chong)電(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)池已(yi)經成為當今電(dian)(dian)(dian)(dian)(dian)子(zi)產品的(de)(de)(de)(de)一種(zhong)標準(zhun)電(dian)(dian)(dian)(dian)(dian)源，特(te)別是便攜設備：筆記本電(dian)(dian)(dian)(dian)(dian)腦(nao)、手機(ji)、數碼(ma)相(xiang)機(ji)。盡管電(dian)(dian)(dian)(dian)(dian)源電(dian)(dian)(dian)(dian)(dian)壓在(zai)不斷降(jiang)低，但可充(chong)電(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)池消(xiao)耗(hao)(hao)的(de)(de)(de)(de)絕對(dui)功率仍在(zai)不斷增(zeng)(zeng)大(da)。功耗(hao)(hao)增(zeng)(zeng)長的(de)(de)(de)(de)主要(yao)原因是設備功能(neng)(neng)的(de)(de)(de)(de)增(zeng)(zeng)強，例(li)如：數碼(ma)相(xiang)機(ji)與手機(ji)的(de)(de)(de)(de)功能(neng)(neng)整

　　概(gai)述充電(dian)(dian)電(dian)(dian)池(chi)(chi)已(yi)經成為當今電(dian)(dian)子產(chan)(chan)品(pin)的(de)(de)一(yi)種標(biao)準電(dian)(dian)源，特別(bie)是(shi)便攜設備：筆(bi)記本電(dian)(dian)腦、手機(ji)、數(shu)碼(ma)相(xiang)機(ji)。盡管(guan)電(dian)(dian)源電(dian)(dian)壓在(zai)不斷(duan)降低，但可(ke)充電(dian)(dian)電(dian)(dian)池(chi)(chi)消耗(hao)的(de)(de)絕對(dui)功(gong)率仍在(zai)不斷(duan)增大。功(gong)耗(hao)增長(chang)的(de)(de)主要(yao)(yao)原(yuan)因是(shi)設備功(gong)能的(de)(de)增強，例如(ru)：數(shu)碼(ma)相(xiang)機(ji)與手機(ji)的(de)(de)功(gong)能整(zheng)合(he)，筆(bi)記本電(dian)(dian)腦更(geng)高(gao)的(de)(de)運(yun)算速(su)度以及(ji)大尺寸屏幕的(de)(de)需(xu)求等等。便攜設備功(gong)耗(hao)的(de)(de)增大使得用(yong)可(ke)充電(dian)(dian)電(dian)(dian)池(chi)(chi)要(yao)(yao)比標(biao)準電(dian)(dian)池(chi)(chi)性價比更(geng)高(gao)。更(geng)為重(zhong)要(yao)(yao)的(de)(de)是(shi)，可(ke)充電(dian)(dian)電(dian)(dian)池(chi)(chi)更(geng)有(you)(you)利于(yu)環保。使用(yong)充電(dian)(dian)電(dian)(dian)池(chi)(chi)可(ke)極大地減(jian)少有(you)(you)害物質的(de)(de)排放、材料的(de)(de)消耗(hao)、以及(ji)生(sheng)產(chan)(chan)同等一(yi)次性電(dian)(dian)池(chi)(chi)所需(xu)的(de)(de)能源。

　　本(ben)文介紹了可充(chong)(chong)電(dian)電(dian)池的(de)化(hua)學成分(fen)；同時(shi)說明了各種充(chong)(chong)電(dian)電(dian)池的(de)典型特(te)征和選擇電(dian)池類型時(shi)需(xu)要(yao)重點注(zhu)意的(de)事項(xiang)。另外還(huan)討論了在不(bu)使用微(wei)控制器或電(dian)源浪涌的(de)主適配器的(de)情(qing)況下如何(he)構(gou)建單(dan)機結構(gou)，安(an)全、快速(su)地(di)對鎳(nie)氫和鋰離子充(chong)(chong)電(dian)電(dian)池進行(xing)充(chong)(chong)電(dian)。

　　可充電(dian)(dian)電(dian)(dian)池類型20世(shi)紀80年代的(de)便攜設備，如數字無繩電(dian)(dian)話、隨(sui)身聽和電(dian)(dian)動剃須(xu)刀等，主要由鎳(nie)鎘(NiCd)電(dian)(dian)池供(gong)電(dian)(dian)。到了90年代后期，鎳(nie)氫(qing)(NiMH)電(dian)(dian)池和鋰離子(Li-Ion)電(dian)(dian)池逐漸進入市場并開始(shi)流(liu)行。

　　因為價(jia)格比鎳(nie)(nie)氫和鋰離子電池(chi)便宜，鎳(nie)(nie)鎘(ge)電池(chi)在(zai)低端(duan)應(ying)用(yong)中十分普遍(bian)。鎳(nie)(nie)鎘(ge)電池(chi)可提(ti)供最高的放電電流，適合短(duan)時間內需要大功率輸出的應(ying)用(yong)。

　　另一(yi)(yi)(yi)方面，鎳鎘(ge)(ge)電(dian)池(chi)(chi)曾(ceng)經被(bei)所謂的(de)(de)記憶效應困擾(現在的(de)(de)鎳鎘(ge)(ge)電(dian)池(chi)(chi)很少考慮這(zhe)個因素)，使電(dian)池(chi)(chi)容(rong)量降(jiang)低。如果鎳鎘(ge)(ge)電(dian)池(chi)(chi)在未完全放(fang)電(dian)的(de)(de)情況下再充(chong)電(dian)，一(yi)(yi)(yi)些活性物(wu)質會(hui)(hui)累積(ji)并且(qie)開始結(jie)晶(在陽極(ji)有100μm的(de)(de)鎘(ge)(ge)累積(ji)層)，通過化學(xue)反應這(zhe)層物(wu)質會(hui)(hui)自行消失(一(yi)(yi)(yi)塊全新電(dian)池(chi)(chi)的(de)(de)陽極(ji)大約有1微米厚(hou)度的(de)(de)鎘(ge)(ge)結(jie)晶)。

　　出現記(ji)憶效應會導致(zhi)電池容量越(yue)來(lai)越(yue)小，端(duan)電壓(ya)(ya)越(yue)來(lai)越(yue)低(di)，使得電池到達最低(di)可用端(duan)電壓(ya)(ya)(關斷(duan)點)的(de)時(shi)間比預期的(de)早許多，如圖1所(suo)示(shi)。鎳鎘(ge)(ge)電池的(de)另一(yi)個缺點是它的(de)活(huo)性物質中含有有毒的(de)鎘(ge)(ge)(Cd)，早期的(de)鎳鎘(ge)(ge)電池在(zai)處理時(shi)會產(chan)生(sheng)和成本(ben)問題。。所(suo)以，歐洲法規2000/53/EG在(zai)2005年12月(yue)31號后銷售(shou)鎳鎘(ge)(ge)充電電池。

　　鎳氫電池比鎳鎘電池更環保，但是價格更貴。鎳氫電池的放電電流略小，但受惰性效應的影響。惰性效應是比鎳鎘電池記憶效應稍輕的一種現象。惰性效應是由于鎳的結晶導致的。惰性效應和記憶效應一樣，導致無法完全使用可充電電池的全部容量，但都可以通過使用帶有放電功能的充電器來避免。

　　圖1.鎳鎘電(dian)池(chi)(chi)的(de)記憶(yi)效應與(yu)鎳氫電(dian)池(chi)(chi)的(de)惰性效應之(zhi)間的(de)比較

　　鋰(li)電子(zi)可充(chong)電電池價格(ge)最(zui)高(gao)，但具有足夠高(gao)的(de)能量(liang)密度，因而可以在給定尺寸下提供(gong)更優性能，更適合(he)小尺寸、高(gao)集成(cheng)度的(de)便攜設(she)備。

　　表(biao)1給出了各種類型電池(chi)的主要特(te)性。

　　表1.各種類型充電(dian)電(dian)池概述

　　MaximumDischargeCurrent>5C<3C<2C

　　室溫下。

　　C=電池容量。

　　單機鎳氫電池快速充電器雖然很(hen)多人更偏(pian)愛鋰離(li)子(zi)電(dian)(dian)池(chi)(chi)(chi)，鎳氫電(dian)(dian)池(chi)(chi)(chi)的使用(yong)依然很(hen)流行。因(yin)為(wei)鎳氫電(dian)(dian)池(chi)(chi)(chi)比鋰離(li)子(zi)電(dian)(dian)池(chi)(chi)(chi)便宜很(hen)多，所以在MP3播放器、閃(shan)光(guang)燈配件、車燈等設備(bei)中經常能看到標準的AA和(he)AAA鎳氫電(dian)(dian)池(chi)(chi)(chi)。

　　一塊可(ke)充電(dian)鎳(nie)氫(qing)電(dian)池的(de)溫(wen)度和端電(dian)壓隨著電(dian)池的(de)充電(dian)逐(zhu)步上升，在(zai)電(dian)池完全充滿后開始下降(jiang)(圖2)。所以，鎳(nie)氫(qing)電(dian)池充電(dian)器(qi)的(de)主要任務是檢測到這個突(tu)變點并(bing)中斷充電(dian)，或者從快速充電(dian)切換到涓流充電(dian)。另(ling)外，在(zai)充電(dian)過程中對溫(wen)度和電(dian)壓進行連續可(ke)以提供系統的(de)安全性。

　　圖2.這些(xie)曲線顯示了NiMH充電(dian)電(dian)池(chi)充電(dian)過程中典型的(de)(de)電(dian)壓(ya)(頂(ding)部)和溫度(du)(底部)隨時間(jian)的(de)(de)變化

　　DS2711/DS2712充電器具(ju)備(bei)上述功(gong)能(neng)。另外，它們可(ke)以(yi)單機工作，不需(xu)要微控制器(qi)或(huo)微處(chu)理器(qi)。該系列產(chan)品是(shi)專門為單節(jie)AA或(huo)AAA可(ke)充(chong)電電池設計的，同時也適用于或(huo)并聯的兩節(jie)電池。DS2711采(cai)用線性控制結構(gou)，DS2712采(cai)用開關控制結構(gou)。為了最大限度地延長工作時間、節(jie)約電池能(neng)量，這些充(chong)電器(qi)有4種(zhong)充(chong)電模式：預(yu)充(chong)電、快速充(chong)電、浮(fu)充(chong)和(he)涓(juan)流充(chong)電。在浮(fu)充(chong)模式下，電池充(chong)滿后充(chong)電速率(lv)被切(qie)換到(dao)一個比較低的速率(lv)(對于DS2711而言是(shi)25%)。

　　簡單充電(dian)(dian)(dian)機電(dian)(dian)(dian)路圖除功能外，DS2711/DS2712充電(dian)(dian)(dian)器還(huan)帶有內部計時(shi)(shi)(shi)(shi)器，通過(guo)連接到(dao)TMR引腳的外部電(dian)(dian)(dian)阻設定最大充電(dian)(dian)(dian)時(shi)(shi)(shi)(shi)間，可將快速充電(dian)(dian)(dian)時(shi)(shi)(shi)(shi)間設置在0.5到(dao)10小時(shi)(shi)(shi)(shi)。浮充時(shi)(shi)(shi)(shi)間已經設定為最大充電(dian)(dian)(dian)時(shi)(shi)(shi)(shi)間的一(yi)半(0.25到(dao)5小時(shi)(shi)(shi)(shi))。根據所要求的充電(dian)(dian)(dian)時(shi)(shi)(shi)(shi)間(TAPPROX)，由下式計算電(dian)(dian)(dian)阻值：

　　R=1000TAPPROX/1.5

　　快速充(chong)電模(mo)式(shi)下，如果(guo)超過最大充(chong)電時間，充(chong)電器(qi)會從(cong)快速充(chong)電模(mo)式(shi)切(qie)(qie)換到浮(fu)充(chong)模(mo)式(shi)，同時復位計(ji)時器(qi)。計(ji)時器(qi)開始為浮(fu)充(chong)過程計(ji)時，如果(guo)達到預(yu)定的(de)浮(fu)充(chong)時間，充(chong)電器(qi)將從(cong)浮(fu)充(chong)模(mo)式(shi)切(qie)(qie)換到涓流模(mo)式(shi)(圖3)。

　　圖3.該典型應用(yong)電(dian)中，DS2711電(dian)池充電(dian)器為2個的(de)鎳氫充電(dian)電(dian)池充電(dian)

　　VP1、VP2用(yong)(yong)于電(dian)(dian)(dian)壓，THM1、THM2配合熱敏電(dian)(dian)(dian)阻用(yong)(yong)來監測(ce)電(dian)(dian)(dian)池(chi)(chi)的(de)(de)溫度(du)。TMR(計時器)和RSNS(檢流(liu)電(dian)(dian)(dian)阻)用(yong)(yong)于設(she)定充電(dian)(dian)(dian)時間和充電(dian)(dian)(dian)電(dian)(dian)(dian)流(liu)。DS2711/DS2712的(de)(de)另(ling)外(wai)一個(ge)特(te)性(xing)是可以檢測(ce)電(dian)(dian)(dian)池(chi)(chi)充電(dian)(dian)(dian)故(gu)障(zhang)和堿性(xing)原電(dian)(dian)(dian)池(chi)(chi)。如(ru)果(guo)發生(sheng)這些(xie)情況，充電(dian)(dian)(dian)器會(hui)自(zi)行(xing)關機。該特(te)性(xing)十(shi)分重要，因為如(ru)果(guo)給(gei)堿性(xing)電(dian)(dian)(dian)池(chi)(chi)充電(dian)(dian)(dian)會(hui)造(zao)成電(dian)(dian)(dian)池(chi)(chi)泄漏，產生(sheng)有害的(de)(de)液體和/或氣體。有毒氣體以及(ji)會(hui)與周圍材料起反(fan)應的(de)(de)液體通(tong)常會(hui)損壞電(dian)(dian)(dian)和/或外(wai)圍設(she)備。

　　如何檢測堿(jian)性電(dian)(dian)(dian)池(chi)(chi)全新的(de)(de)鎳(nie)氫AA電(dian)(dian)(dian)池(chi)(chi)的(de)(de)典(dian)型(xing)內(nei)阻(zu)(zu)在(zai)30mΩ到(dao)100mΩ，堿(jian)性電(dian)(dian)(dian)池(chi)(chi)的(de)(de)內(nei)阻(zu)(zu)一般在(zai)200mΩ到(dao)300mΩ(根據充電(dian)(dian)(dian)狀(zhuang)態，最(zui)高(gao)可(ke)到(dao)700mΩ)，出現故(gu)障的(de)(de)充電(dian)(dian)(dian)電(dian)(dian)(dian)池(chi)(chi)會有很高(gao)的(de)(de)內(nei)阻(zu)(zu)。DS2711/DS2712通過檢測到(dao)的(de)(de)電(dian)(dian)(dian)池(chi)(chi)電(dian)(dian)(dian)壓(VP1和VP2)和已(yi)設(she)定的(de)(de)充電(dian)(dian)(dian)電(dian)(dian)(dian)流可(ke)以計(ji)算出待充電(dian)(dian)(dian)電(dian)(dian)(dian)池(chi)(chi)的(de)(de)內(nei)阻(zu)(zu)。

　　CTST引腳(用于(yu)電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)測(ce)(ce)試、設置門限)控(kong)制電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)內阻的測(ce)(ce)量。VCTST是(shi)充電(dian)(dian)(dian)(dian)(dian)(dian)過程中的電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)電(dian)(dian)(dian)(dian)(dian)(dian)壓減(jian)去(qu)無充電(dian)(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)(dian)流時(shi)的開電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)電(dian)(dian)(dian)(dian)(dian)(dian)壓(OCV)后(hou)的差(cha)值(zhi)。這(zhe)個(ge)值(zhi)等于(yu)充電(dian)(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)(dian)流乘以電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)內阻的乘積。如果檢(jian)測(ce)(ce)引腳(VP1、VP2和(he)VN1)與電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)沒有采用Kelvin連接，引線電(dian)(dian)(dian)(dian)(dian)(dian)阻也(ye)將計入測(ce)(ce)量值(zhi)，影響(xiang)VCTST。計算外(wai)部電(dian)(dian)(dian)(dian)(dian)(dian)阻RCTST的公式(shi)為：

　　RCTST=8000[V2/A]/VCTST,whereVCTST=ICharge×RCELL

　　圖4.圖3中所示充電器的充電流程

　　單機鋰離子(zi)電(dian)(dian)(dian)(dian)池(chi)快速(su)充(chong)(chong)電(dian)(dian)(dian)(dian)器(qi)因為不需(xu)要(yao)檢測(ce)電(dian)(dian)(dian)(dian)壓變化率(dV/dt)，鋰離子(zi)電(dian)(dian)(dian)(dian)池(chi)充(chong)(chong)電(dian)(dian)(dian)(dian)器(qi)比鎳(nie)氫電(dian)(dian)(dian)(dian)池(chi)簡單。同(tong)時，由于(yu)鋰離子(zi)電(dian)(dian)(dian)(dian)池(chi)對(dui)過(guo)充(chong)(chong)非常，充(chong)(chong)電(dian)(dian)(dian)(dian)器(qi)需(xu)要(yao)一(yi)個精確的4.2V±50mV電(dian)(dian)(dian)(dian)源恒電(dian)(dian)(dian)(dian)流充(chong)(chong)電(dian)(dian)(dian)(dian)。至于(yu)鎳(nie)氫電(dian)(dian)(dian)(dian)池(chi)，充(chong)(chong)電(dian)(dian)(dian)(dian)器(qi)不僅需(xu)要(yao)電(dian)(dian)(dian)(dian)壓監測(ce)，還需(xu)要(yao)其(qi)它功能(溫度、計時等)。

　　單機鋰離子電池充電器MAX8601內置所謂的VBATT可控電壓源，它可以在+25°C提供4.2V±0.021V，或在40°C

　　圖5.MAX8601鋰離子電池單機(ji)充(chong)電器的(de)典型應用電圖

　　MAX8601充(chong)(chong)電(dian)(dian)(dian)(dian)器(qi)的主要優點是可(ke)以(yi)通(tong)過(guo)外(wai)部適(shi)(shi)(shi)配器(qi)或(huo)USB端(duan)口給電(dian)(dian)(dian)(dian)池(chi)充(chong)(chong)電(dian)(dian)(dian)(dian)(圖6)。USB端(duan)口根(gen)據USEL引腳的設置可(ke)以(yi)提(ti)(ti)供(gong)(gong)100mA、500mA電(dian)(dian)(dian)(dian)流(liu)(典(dian)型USB輸出(chu)電(dian)(dian)(dian)(dian)流(liu))。該芯片(pian)會自動(dong)選(xuan)擇(ze)外(wai)部電(dian)(dian)(dian)(dian)源(主適(shi)(shi)(shi)配器(qi)或(huo)USB)。如(ru)果兩個電(dian)(dian)(dian)(dian)源同時存在，它(ta)會選(xuan)擇(ze)主適(shi)(shi)(shi)配器(qi)進行(xing)充(chong)(chong)電(dian)(dian)(dian)(dian)。任何一個電(dian)(dian)(dian)(dian)源都必須能(neng)夠提(ti)(ti)供(gong)(gong)最小4.5V的電(dian)(dian)(dian)(dian)壓。通(tong)過(guo)USB端(duan)口充(chong)(chong)電(dian)(dian)(dian)(dian)可(ke)以(yi)降低(di)外(wai)部電(dian)(dian)(dian)(dian)源模塊的成本，電(dian)(dian)(dian)(dian)源模塊通(tong)常體積較大且效率較低(di)。

　　MAX8601具有低電(dian)(dian)(dian)(dian)池(chi)(chi)電(dian)(dian)(dian)(dian)壓預充(chong)(chong)、限壓/限流快速充(chong)(chong)電(dian)(dian)(dian)(dian)和浮充(chong)(chong)模(mo)式(shi)等(deng)控制算(suan)法，優(you)化(hua)了(le)鋰離子電(dian)(dian)(dian)(dian)池(chi)(chi)充(chong)(chong)電(dian)(dian)(dian)(dian)。器(qi)件(jian)還有上電(dian)(dian)(dian)(dian)復(fu)位以(yi)及電(dian)(dian)(dian)(dian)池(chi)(chi)過壓、高溫(wen)/低溫(wen)檢(jian)測和充(chong)(chong)電(dian)(dian)(dian)(dian)時(shi)間(jian)的(de)連續監測功能。充(chong)(chong)電(dian)(dian)(dian)(dian)過程中出現過壓、高溫(wen)或(huo)低溫(wen)會造(zao)成充(chong)(chong)電(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)池(chi)(chi)的(de)永(yong)久損壞(huai)(huai)，降低電(dian)(dian)(dian)(dian)池(chi)(chi)容(rong)量和使(shi)用時(shi)間(jian)，甚至(zhi)使(shi)電(dian)(dian)(dian)(dian)池(chi)(chi)報廢。最(zui)壞(huai)(huai)的(de)情(qing)況下，會造(zao)成電(dian)(dian)(dian)(dian)池(chi)(chi)泄漏或(huo)爆炸。MAX8601確保充(chong)(chong)電(dian)(dian)(dian)(dian)過程中不會出現上述危害，從而延(yan)長(chang)了(le)電(dian)(dian)(dian)(dian)池(chi)(chi)使(shi)用時(shi)間(jian)，消除了(le)潛(qian)在的(de)情(qing)況。

　　圖6.圖5中充電器的充電流程圖

　　結論DS2711/DS2712和(he)MAX8601都(dou)是(shi)單機充電器，它(ta)們具有多(duo)種(zhong)功能(neng)(電壓(ya)、功率(lv)、溫度(du)、計時(shi)等)，既不需(xu)要(yao)微控制(zhi)器，也不需(xu)要(yao)電源浪涌，而且提供清晰、簡(jian)單的外部切換。

　　常見問題及解答

　　什么(me)場合不適(shi)合使用可再充電電池？

　　答：不要在諸(zhu)如(ru)遙控和煙霧報警等應(ying)用(yong)中使用(yong)充(chong)電(dian)電(dian)池(chi)。因(yin)為這些應(ying)用(yong)的電(dian)源要求比較低，而(er)(er)且設備不經(jing)常使用(yong)。可再(zai)充(chong)電(dian)電(dian)池(chi)比普通電(dian)池(chi)具有更高的自放電(dian)率。譬如(ru)，鎳氫電(dian)池(chi)每天損失1%的電(dian)量。因(yin)而(er)(er)它(ta)的工(gong)作時間(jian)不太長。

　　能否給一次性電池(如堿性電池)充電？

　　答：不能(neng)給堿(jian)性(xing)電(dian)(dian)池充電(dian)(dian)。堿(jian)性(xing)電(dian)(dian)池的(de)化學成(cheng)分及(ji)構造不適合進行充電(dian)(dian)，入的(de)能(neng)量(liang)會發(fa)熱，隨著內(nei)部(bu)溫度的(de)上升，電(dian)(dian)池通常會出(chu)現(xian)泄漏(lou)現(xian)象，有(you)時可(ke)能(neng)會爆(bao)炸。電(dian)(dian)池內(nei)部(bu)的(de)有(you)毒物質對的(de)影響很大。

　　為什(shen)么監測充電電池的溫度十分(fen)重要？

　　答：盡管充(chong)(chong)電(dian)(dian)電(dian)(dian)池(chi)的(de)(de)化(hua)學成分(fen)及(ji)構造適合進行充(chong)(chong)電(dian)(dian)，但對電(dian)(dian)池(chi)允許的(de)(de)電(dian)(dian)量(liang)及(ji)充(chong)(chong)電(dian)(dian)速(su)率有所。短(duan)時間內充(chong)(chong)入過(guo)多(duo)電(dian)(dian)量(liang)會(hui)使(shi)(shi)內部溫(wen)(wen)度升高(gao)，同(tong)(tong)堿性(xing)電(dian)(dian)池(chi)一樣(yang)，可(ke)能造成電(dian)(dian)池(chi)泄漏甚至爆炸。一旦充(chong)(chong)電(dian)(dian)電(dian)(dian)池(chi)充(chong)(chong)滿電(dian)(dian)，額(e)外的(de)(de)電(dian)(dian)荷會(hui)使(shi)(shi)電(dian)(dian)池(chi)發熱。如(ru)果不對溫(wen)(wen)度進行監(jian)測，并降低充(chong)(chong)電(dian)(dian)速(su)率或停止充(chong)(chong)電(dian)(dian)，可(ke)能會(hui)對產生同(tong)(tong)樣(yang)的(de)(de)危害(hai)。這就是(shi)DS2711/DS2712/MAX8601在充(chong)(chong)電(dian)(dian)過(guo)程(cheng)中監(jian)測諸多(duo)參數的(de)(de)原因(yin)所在，這樣(yang)將確保較長(chang)的(de)(de)電(dian)(dian)池(chi)使(shi)(shi)用時間以及(ji)安全的(de)(de)充(chong)(chong)電(dian)(dian)過(guo)程(cheng)。