電(dian)(dian)動車電(dian)(dian)池隨著使用時間的長短，自身(shen)硫化現象不可(ke)避(bi)免的存(cun)在。很多(duo)消(xiao)費者不了解為(wei)什(shen)么(me)電(dian)(dian)池用兩年就(jiu)需要更(geng)換(huan)，是什(shen)么(me)原因造(zao)成了電(dian)(dian)動車電(dian)(dian)池報(bao)廢(fei)？

      與其(qi)它(ta)鉛酸蓄電池(chi)的使(shi)用環境不同(tong)，電動自(zi)行(xing)車電池(chi)的失效原因有其(qi)特殊性。電動自(zi)行(xing)車的電池(chi)的循環次數遠遠多后備(bei)電源類的電池(chi)。

      例如，原郵電(dian)(dian)(dian)(dian)部(bu)[1994]763號電(dian)(dian)(dian)(dian)信網維(wei)護規程的(de)規定，每年(nian)應以實(shi)際負荷做一(yi)次(ci)核對性放(fang)電(dian)(dian)(dian)(dian)試驗，放(fang)出容(rong)(rong)量的(de)30％～40％。每3年(nian)做一(yi)次(ci)容(rong)(rong)量試驗，到(dao)使用6年(nian)以后(hou)，每年(nian)做一(yi)次(ci)容(rong)(rong)量試驗。這(zhe)樣，電(dian)(dian)(dian)(dian)信的(de)電(dian)(dian)(dian)(dian)池(chi)(chi)如果不是(shi)頻(pin)繁的(de)出現停(ting)電(dian)(dian)(dian)(dian)，電(dian)(dian)(dian)(dian)池(chi)(chi)很少(shao)處于(yu)放(fang)電(dian)(dian)(dian)(dian)狀(zhuang)態。假定每年(nian)遇到(dao)4次(ci)停(ting)電(dian)(dian)(dian)(dian)，這(zhe)樣，在10年(nian)間電(dian)(dian)(dian)(dian)池(chi)(chi)放(fang)電(dian)(dian)(dian)(dian)也(ye)就是(shi)40次(ci)，所以電(dian)(dian)(dian)(dian)池(chi)(chi)的(de)深循環壽(shou)命定為80次(ci)。同時，電(dian)(dian)(dian)(dian)信系(xi)統(tong)的(de)電(dian)(dian)(dian)(dian)池(chi)(chi)放(fang)電(dian)(dian)(dian)(dian)深度也(ye)就是(shi)按(an)照30％～40％。

      而(er)電(dian)(dian)(dian)(dian)動自行(xing)車使用的(de)(de)(de)(de)電(dian)(dian)(dian)(dian)池依據標(biao)(biao)準，電(dian)(dian)(dian)(dian)池的(de)(de)(de)(de)壽命應該是按照70％標(biao)(biao)稱容(rong)量(liang)的(de)(de)(de)(de)放電(dian)(dian)(dian)(dian)要達到350次。這(zhe)樣，電(dian)(dian)(dian)(dian)動自行(xing)車電(dian)(dian)(dian)(dian)池的(de)(de)(de)(de)放電(dian)(dian)(dian)(dian)深(shen)度(du)和循環(huan)壽命遠遠超(chao)過(guo)電(dian)(dian)(dian)(dian)信(xin)系統的(de)(de)(de)(de)電(dian)(dian)(dian)(dian)池要求(qiu)。另外(wai)，電(dian)(dian)(dian)(dian)動自行(xing)車電(dian)(dian)(dian)(dian)池要求(qiu)在8小時以內完(wan)成充電(dian)(dian)(dian)(dian)。這(zhe)樣，不得不提(ti)高(gao)充電(dian)(dian)(dian)(dian)的(de)(de)(de)(de)電(dian)(dian)(dian)(dian)壓(ya)值，超(chao)過(guo)了(le)電(dian)(dian)(dian)(dian)池的(de)(de)(de)(de)大量(liang)析氣電(dian)(dian)(dian)(dian)壓(ya)2.42V而(er)形成了(le)較塊速度(du)的(de)(de)(de)(de)失水。而(er)電(dian)(dian)(dian)(dian)信(xin)系統的(de)(de)(de)(de)電(dian)(dian)(dian)(dian)池是完(wan)全沒(mei)有這(zhe)樣高(gao)的(de)(de)(de)(de)充電(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)壓(ya)的(de)(de)(de)(de)。

      同(tong)時，電(dian)動自(zi)(zi)行車(che)電(dian)池(chi)(chi)(chi)(chi)的(de)(de)(de)(de)放(fang)電(dian)電(dian)流很(hen)大(da)，就(jiu)是(shi)巡航期間(jian)(jian)的(de)(de)(de)(de)放(fang)電(dian)電(dian)流也(ye)接近于0.5C放(fang)電(dian)，啟動的(de)(de)(de)(de)時候(hou)，放(fang)電(dian)電(dian)流會超過1C放(fang)電(dian)的(de)(de)(de)(de)。這樣，也(ye)在影響電(dian)池(chi)(chi)(chi)(chi)的(de)(de)(de)(de)使用(yong)壽命。由(you)于電(dian)池(chi)(chi)(chi)(chi)特(te)性的(de)(de)(de)(de)特(te)殊(shu)要求，我們看到一些(xie)可(ke)以給核電(dian)站供(gong)(gong)應(ying)鉛酸蓄電(dian)池(chi)(chi)(chi)(chi)的(de)(de)(de)(de)制(zhi)(zhi)造(zao)(zao)(zao)商(shang)也(ye)沒有(you)步入電(dian)動自(zi)(zi)行車(che)電(dian)池(chi)(chi)(chi)(chi)供(gong)(gong)應(ying)商(shang)的(de)(de)(de)(de)行列。一些(xie)規模(mo)可(ke)觀的(de)(de)(de)(de)電(dian)池(chi)(chi)(chi)(chi)制(zhi)(zhi)造(zao)(zao)(zao)商(shang)也(ye)逐步退出了(le)(le)電(dian)動自(zi)(zi)行車(che)電(dian)池(chi)(chi)(chi)(chi)供(gong)(gong)應(ying)商(shang)的(de)(de)(de)(de)行列。而給電(dian)動自(zi)(zi)行車(che)供(gong)(gong)貨的(de)(de)(de)(de)電(dian)池(chi)(chi)(chi)(chi)制(zhi)(zhi)造(zao)(zao)(zao)商(shang)除(chu)了(le)(le)沈陽松下以外(wai)，就(jiu)沒有(you)幾個(ge)成規模(mo)的(de)(de)(de)(de)電(dian)池(chi)(chi)(chi)(chi)制(zhi)(zhi)造(zao)(zao)(zao)商(shang)。雖(sui)然沈陽松下供(gong)(gong)應(ying)的(de)(de)(de)(de)電(dian)池(chi)(chi)(chi)(chi)的(de)(de)(de)(de)初期容(rong)量相(xiang)對最(zui)低(di)，按照行業標(biao)準檢驗(yan)，其容(rong)量在合(he)格與(yu)不(bu)合(he)格之間(jian)(jian)，但是(shi)，其壽命相(xiang)對比較長。

      這樣(yang)，電(dian)(dian)動自行車使用的(de)(de)(de)電(dian)(dian)池的(de)(de)(de)性能要求與傳統(tong)的(de)(de)(de)密封(feng)電(dian)(dian)池不同(tong)，失效模式與傳統(tong)的(de)(de)(de)電(dian)(dian)池失效模式存在(zai)很(hen)大的(de)(de)(de)差異。出(chu)現了一些過去少見的(de)(de)(de)失效模式和失效比例。

      一個主(zhu)要(yao)的(de)區別是(shi)放電(dian)率(lv)的(de)差異。普通的(de)閥控密封式鉛酸蓄電(dian)池的(de)放電(dian)率(lv)多數是(shi)以10小時(shi)(shi)率(lv)或(huo)者(zhe)20小時(shi)(shi)率(lv)來制(zhi)定的(de)，而電(dian)動(dong)自行(xing)(xing)車的(de)電(dian)池都是(shi)以2小時(shi)(shi)率(lv)或(huo)者(zhe)3小時(shi)(shi)率(lv)來制(zhi)定的(de)，這與電(dian)池的(de)實際使用情況大體相當。所以，在(zai)供應電(dian)動(dong)自行(xing)(xing)車電(dian)池的(de)初(chu)期，電(dian)池容量(liang)是(shi)最大的(de)問題。為了提高電(dian)池的(de)容量(liang)，各(ge)個電(dian)池制(zhi)造(zao)商采(cai)取(qu)了多種(zhong)方法(fa)。

以大量使(shi)用的10Ah電池為例，最典型的方法如下：

      1、 增加(jia)極(ji)板數量

      把原設計的(de)單格5片(pian)(pian)(pian)6片(pian)(pian)(pian)改為6片(pian)(pian)(pian)7片(pian)(pian)(pian)，7片(pian)(pian)(pian)8片(pian)(pian)(pian)，甚(shen)至(zhi)8片(pian)(pian)(pian)9片(pian)(pian)(pian)。靠減薄極板厚度和(he)隔板，增加極板數量來提高電池容(rong)量。

      2、 提高電池的(de)硫酸比重

      原來浮充(chong)電池(chi)(chi)的(de)(de)硫(liu)酸比重一般都在1.21~1.28之間(jian)，而電動自行車的(de)(de)電池(chi)(chi)的(de)(de)硫(liu)酸比重一般都在1.36～1.38左(zuo)右。只有(you)極少數的(de)(de)采用(yong)1.32的(de)(de)比重。

      3、 增加正極板(ban)活性物質用量(liang)

      4、 低溫(wen)固化，增(zeng)加β氧化鉛的(de)比(bi)例

      一般(ban)密封電(dian)(dian)池(chi)(chi)(chi)為了實現氧循環(huan)，都要(yao)(yao)求做(zuo)好負極過度(du)。增加正(zheng)極板活性物(wu)質用量，可以(yi)提高電(dian)(dian)池(chi)(chi)(chi)的容量，是(shi)以(yi)降低(di)氧循環(huan)為代價的。通過這些主(zhu)要(yao)(yao)措施(shi)，電(dian)(dian)池(chi)(chi)(chi)的初期容量滿足了電(dian)(dian)動自(zi)行車的容量要(yao)(yao)求，特(te)別是(shi)改善(shan)了電(dian)(dian)池(chi)(chi)(chi)的大(da)電(dian)(dian)流放(fang)電(dian)(dian)的特(te)性，延長了電(dian)(dian)池(chi)(chi)(chi)大(da)電(dian)(dian)流放(fang)電(dian)(dian)的壽(shou)命。但是(shi)，這些措施(shi)也(ye)制約著電(dian)(dian)池(chi)(chi)(chi)壽(shou)命。

      一、電(dian)池失水問(wen)題

      產生電池失水的一(yi)些原因主要如下(xia)：

      1、為了滿(man)足電(dian)(dian)(dian)(dian)(dian)池在(zai)8小時以(yi)內充(chong)(chong)滿(man)電(dian)(dian)(dian)(dian)(dian)，所以(yi)在(zai)三段式恒(heng)壓限(xian)流(liu)充(chong)(chong)電(dian)(dian)(dian)(dian)(dian)中(zhong)，不(bu)(bu)得(de)不(bu)(bu)通過恒(heng)壓值，達到折(zhe)合單格電(dian)(dian)(dian)(dian)(dian)池電(dian)(dian)(dian)(dian)(dian)壓為2.47V～2.49V。這(zhe)樣(yang)，大(da)大(da)超過電(dian)(dian)(dian)(dian)(dian)池正極板(ban)析氧電(dian)(dian)(dian)(dian)(dian)壓的(de)(de)(de)2.35V和負(fu)極板(ban)析氫電(dian)(dian)(dian)(dian)(dian)壓的(de)(de)(de)2.42V。一些充(chong)(chong)電(dian)(dian)(dian)(dian)(dian)器(qi)制造商的(de)(de)(de)產(chan)品為了降低充(chong)(chong)電(dian)(dian)(dian)(dian)(dian)時間的(de)(de)(de)指示，提高了恒(heng)壓轉浮充(chong)(chong)的(de)(de)(de)電(dian)(dian)(dian)(dian)(dian)流(liu)，而使(shi)得(de)充(chong)(chong)電(dian)(dian)(dian)(dian)(dian)指示充(chong)(chong)滿(man)電(dian)(dian)(dian)(dian)(dian)以(yi)后，還(huan)沒有充(chong)(chong)滿(man)電(dian)(dian)(dian)(dian)(dian)，就靠提高浮充(chong)(chong)電(dian)(dian)(dian)(dian)(dian)壓來彌補。這(zhe)樣(yang)，很(hen)多充(chong)(chong)電(dian)(dian)(dian)(dian)(dian)器(qi)的(de)(de)(de)浮充(chong)(chong)電(dian)(dian)(dian)(dian)(dian)壓超過單格電(dian)(dian)(dian)(dian)(dian)壓2.35V，這(zhe)樣(yang)在(zai)浮充(chong)(chong)階(jie)段還(huan)在(zai)大(da)量析氧。而電(dian)(dian)(dian)(dian)(dian)池的(de)(de)(de)氧循環又不(bu)(bu)好，這(zhe)樣(yang)在(zai)浮充(chong)(chong)階(jie)段也在(zai)不(bu)(bu)斷的(de)(de)(de)排氣。

      2、一(yi)些電池制造商沒(mei)有找到好的(de)板(ban)柵合金(jin)(jin)，仍然采用低(di)銻合金(jin)(jin)，這樣，比鉛鈣(gai)系列的(de)板(ban)柵合金(jin)(jin)析(xi)氣電位低(di)，電池出氣量大，失水相對嚴重。

      3、增加極(ji)板和增加正(zheng)極(ji)板活性(xing)物(wu)質(zhi)用量以后(hou)，負極(ji)過渡不足，氧(yang)循環下降(jiang)，充電過程中正(zheng)極(ji)板的氧(yang)氣(qi)來不及被負極(ji)板吸收，而產生失水。

      4、一些電(dian)池(chi)的開(kai)閥壓(ya)偏(pian)低，容易排氣(qi)，同時電(dian)池(chi)內部的氧分(fen)壓(ya)低，降(jiang)低了氧循環能力，增加了析氣(qi)量(liang)。

      5、由于電(dian)(dian)池(chi)的(de)(de)(de)(de)(de)硫(liu)(liu)酸(suan)比(bi)重(zhong)相對(dui)高(gao)了(le)很多，所(suo)以(yi)(yi)，電(dian)(dian)池(chi)的(de)(de)(de)(de)(de)硫(liu)(liu)化也相對(dui)嚴重(zhong)。電(dian)(dian)池(chi)放電(dian)(dian)以(yi)(yi)后到第二(er)天充電(dian)(dian)以(yi)(yi)前，硫(liu)(liu)酸(suan)比(bi)重(zhong)高(gao)的(de)(de)(de)(de)(de)電(dian)(dian)池(chi)的(de)(de)(de)(de)(de)硫(liu)(liu)化明顯。這樣(yang)(yang)，更加降(jiang)低了(le)負極板氧循環的(de)(de)(de)(de)(de)能力。而失水以(yi)(yi)后的(de)(de)(de)(de)(de)電(dian)(dian)池(chi)，失去的(de)(de)(de)(de)(de)主要是水，留下(xia)了(le)硫(liu)(liu)酸(suan)的(de)(de)(de)(de)(de)成分，相當于進一步提高(gao)了(le)硫(liu)(liu)酸(suan)的(de)(de)(de)(de)(de)比(bi)重(zhong)，這樣(yang)(yang)就使電(dian)(dian)池(chi)更加容易(yi)硫(liu)(liu)化。所(suo)以(yi)(yi)，電(dian)(dian)池(chi)的(de)(de)(de)(de)(de)硫(liu)(liu)化加重(zhong)了(le)失水，失水又加重(zhong)了(le)硫(liu)(liu)化。

      為了(le)克服電(dian)池(chi)的失(shi)水(shui)，一些電(dian)池(chi)制(zhi)(zhi)造商(shang)采(cai)取了(le)不少措施。在板柵合金(jin)方面，一些電(dian)池(chi)制(zhi)(zhi)造商(shang)采(cai)用了(le)多種(zhong)方式，去掉(diao)了(le)低銻(ti)合金(jin)而采(cai)用鉛鈣(gai)錫鋁合金(jin)。提高(gao)了(le)電(dian)池(chi)析氣電(dian)壓。同(tong)時，緩解了(le)鉛鈣(gai)合金(jin)的析鈣(gai)問(wen)題，克服了(le)鉛鈣(gai)合金(jin)的早期容(rong)量損失(shi)的意外容(rong)量下降。同(tong)時，還要解決大電(dian)流放電(dian)特(te)性下降的問(wen)題。

      令人遺(yi)憾(han)的(de)是(shi)(shi)，山東某電(dian)(dian)(dian)池(chi)(chi)(chi)制造(zao)商采(cai)用(yong)軍工技術(shu)，做出了(le)銅網電(dian)(dian)(dian)池(chi)(chi)(chi)，試驗結果證明，其各(ge)項(xiang)參數(shu)都非常(chang)優秀(xiu)，但(dan)是(shi)(shi)，可能因為成本問題，沒有見到他們大(da)批量生(sheng)產和推廣。一些(xie)(xie)電(dian)(dian)(dian)池(chi)(chi)(chi)制造(zao)商改(gai)進(jin)了(le)電(dian)(dian)(dian)池(chi)(chi)(chi)塑(su)料(liao)模具的(de)結構尺寸，增加了(le)電(dian)(dian)(dian)池(chi)(chi)(chi)的(de)開閥壓，降低了(le)電(dian)(dian)(dian)池(chi)(chi)(chi)開閥壓的(de)離散性(xing)，改(gai)善了(le)氧循環。最(zui)重要的(de)一個進(jin)步就是(shi)(shi)采(cai)用(yong)抗失(shi)水的(de)膠體(ti)電(dian)(dian)(dian)池(chi)(chi)(chi)結構，大(da)大(da)的(de)改(gai)善了(le)氧循環。同時，也出現了(le)膠體(ti)電(dian)(dian)(dian)池(chi)(chi)(chi)容(rong)(rong)易(yi)熱失(shi)控(kong)的(de)故(gu)障。為了(le)緩解電(dian)(dian)(dian)池(chi)(chi)(chi)的(de)失(shi)水和熱失(shi)控(kong)，一些(xie)(xie)電(dian)(dian)(dian)池(chi)(chi)(chi)制造(zao)商要求充(chong)電(dian)(dian)(dian)器制造(zao)商降低恒壓值。但(dan)是(shi)(shi)，簡(jian)單的(de)降低恒壓值，沒有降低恒壓轉(zhuan)浮充(chong)的(de)電(dian)(dian)(dian)流(liu)，電(dian)(dian)(dian)池(chi)(chi)(chi)難免(mian)發(fa)生(sheng)欠充(chong)電(dian)(dian)(dian)累積，形(xing)成電(dian)(dian)(dian)池(chi)(chi)(chi)容(rong)(rong)量下降。

      有創(chuang)意的(de)是一些(xie)電(dian)池制造(zao)商(shang)面臨著電(dian)池失水，采取了(le)一些(xie)措施(shi)，在全(quan)國設立(li)了(le)補(bu)水站，電(dian)池也(ye)為補(bu)水改進(jin)了(le)結構。利(li)用(yong)修舊利(li)舊，使平(ping)均(jun)8個月的(de)電(dian)池壽命(ming)延長到平(ping)均(jun)13個月。

      為了(le)(le)改(gai)善膠體電(dian)池(chi)的(de)熱失控，最近市(shi)場上(shang)開(kai)始(shi)見到一些“半膠體電(dian)池(chi)”，就是在(zai)(zai)灌酸的(de)后期，在(zai)(zai)電(dian)池(chi)上(shang)面再(zai)增加(jia)膠體。這樣，相當(dang)于給普(pu)通(tong)的(de)AGM隔(ge)板(ban)電(dian)池(chi)增加(jia)了(le)(le)一層彈性(xing)的(de)氣密隔(ge)離，增加(jia)了(le)(le)隔(ge)板(ban)之間的(de)氣體壓力(li)，改(gai)善了(le)(le)氧循環。同時，比(bi)膠體電(dian)池(chi)的(de)局部(bu)壓力(li)小，平均(jun)壓力(li)不(bu)小。這樣克服了(le)(le)局部(bu)高(gao)氣壓，緩(huan)解了(le)(le)氧循環產生局部(bu)高(gao)熱。

      其結果是(shi)：氧(yang)循環好于普通AGM隔板(ban)電池(chi)，熱失控低于膠(jiao)(jiao)體(ti)電池(chi)，而(er)材(cai)料成本也(ye)低于膠(jiao)(jiao)體(ti)電池(chi)。

      二、電(dian)池硫(liu)化問題(ti)

      在(zai)解剖失效電(dian)(dian)池(chi)中，單純(chun)硫化(hua)(hua)失效的(de)(de)(de)電(dian)(dian)池(chi)不(bu)是很多，但是，幾乎(hu)所有的(de)(de)(de)電(dian)(dian)池(chi)都不(bu)同程度的(de)(de)(de)存(cun)在(zai)著(zhu)硫化(hua)(hua)。一些電(dian)(dian)池(chi)在(zai)做70%的(de)(de)(de)1C充(chong)電(dian)(dian)和60％的(de)(de)(de)2C放電(dian)(dian)中，由于(yu)采(cai)用連續大電(dian)(dian)流循環，破(po)(po)壞(huai)了電(dian)(dian)池(chi)生成大硫酸鉛結晶的(de)(de)(de)條件，所以可能看不(bu)到(dao)硫化(hua)(hua)對(dui)電(dian)(dian)池(chi)的(de)(de)(de)破(po)(po)壞(huai)。如果試驗(yan)中途停頓(dun)，電(dian)(dian)池(chi)硫化(hua)(hua)的(de)(de)(de)問題就會顯現。

      由(you)于電(dian)(dian)池(chi)(chi)(chi)(chi)重量大，一些用戶經常(chang)采取電(dian)(dian)池(chi)(chi)(chi)(chi)經過多(duo)次使用放(fang)完電(dian)(dian)才再次充(chong)電(dian)(dian)，這(zhe)樣(yang)(yang)電(dian)(dian)池(chi)(chi)(chi)(chi)放(fang)電(dian)(dian)以后沒有及時充(chong)電(dian)(dian)，電(dian)(dian)池(chi)(chi)(chi)(chi)的硫化就(jiu)比較嚴重。另外，電(dian)(dian)池(chi)(chi)(chi)(chi)的硫酸(suan)比重比較高(gao)，也(ye)是硫化的重要(yao)因(yin)素。而電(dian)(dian)池(chi)(chi)(chi)(chi)的硫化，破壞(huai)了(le)負極板氧循環的能力，形成更(geng)加(jia)容(rong)易(yi)失水(shui)。這(zhe)樣(yang)(yang)，電(dian)(dian)池(chi)(chi)(chi)(chi)的硫酸(suan)比重更(geng)加(jia)高(gao)，導致更(geng)加(jia)容(rong)易(yi)硫化。

      所以，電(dian)池硫化的(de)程度可能不同，但是(shi)對(dui)電(dian)池的(de)壽命影響也(ye)是(shi)不可忽(hu)略的(de)。

      三、漏酸問題

      在(zai)(zai)電(dian)池密(mi)封和排氣閥沒(mei)有(you)問題的(de)時候(hou)，也會(hui)出現漏液(ye)(ye)。很(hen)多電(dian)池在(zai)(zai)灌酸以(yi)后，電(dian)池處(chu)于(yu)富液(ye)(ye)狀態(tai)，電(dian)池沒(mei)有(you)氧循環(huan)。靠(kao)電(dian)池處(chu)于(yu)開口(kou)狀態(tai)的(de)三充二放把多于(yu)的(de)電(dian)解液(ye)(ye)排出。硫酸比重再次提高(gao)。在(zai)(zai)蓋(gai)排氣閥的(de)時候(hou)，電(dian)解液(ye)(ye)沒(mei)有(you)吸光，還(huan)存在(zai)(zai)游(you)離酸。即(ji)時把游(you)離酸吸光，電(dian)池還(huan)是處(chu)在(zai)(zai)“準貧液(ye)(ye)”狀態(tai)。

      隔(ge)板中(zhong)的(de)電解液相對要多一些。而隔(ge)板中(zhong)稍多的(de)電解液影(ying)響氧(yang)循(xun)環(huan)，這樣，對新(xin)電池進行充(chong)電的(de)時(shi)候，排氣量比較大，代(dai)出的(de)硫(liu)酸(suan)比較多。形(xing)成“漏酸(suan)”。而膠體電池前50～100個循(xun)環(huan)，電池處于富液到貧液的(de)轉換(huan)期，排氣比較嚴重，排氣代(dai)出膠體微粒形(xing)成了(le)“漏酸(suan)”。

      四、正極板軟(ruan)化(hua)問題

      正極板活(huo)性物(wu)質的(de)(de)有效成分是(shi)氧化(hua)鉛，氧化(hua)鉛分α－PbO2和β－PbO2，其中(zhong)，α－PbO2是(shi)活(huo)性物(wu)質的(de)(de)骨(gu)架，容量比較小；β－PbO2依附α－PbO2構成的(de)(de)骨(gu)架上面，其荷電能力比α－PbO2強很多(duo)。

      氧(yang)(yang)化(hua)鉛(qian)放(fang)電(dian)(dian)放(fang)電(dian)(dian)以(yi)后(hou)輸出(chu)硫酸鉛(qian)，充(chong)電(dian)(dian)時硫酸鉛(qian)生(sheng)(sheng)產(chan)氧(yang)(yang)化(hua)鉛(qian)。而充(chong)電(dian)(dian)的(de)時候，在(zai)強酸環境(jing)中只能夠生(sheng)(sheng)成(cheng)β－PbO2。所以(yi)電(dian)(dian)池深放(fang)電(dian)(dian)以(yi)后(hou)，一旦具有骨(gu)架作(zuo)用(yong)的(de)α－PbO2參(can)與放(fang)電(dian)(dian)生(sheng)(sheng)成(cheng)硫酸鉛(qian)以(yi)后(hou)，就(jiu)再(zai)也不能夠恢復成(cheng)為α－PbO2，而充(chong)電(dian)(dian)只能生(sheng)(sheng)成(cheng)β－PbO2。正極板軟化(hua)就(jiu)出(chu)現了(le)。正極板一旦出(chu)現軟化(hua)，起到支持作(zuo)用(yong)的(de)多孔結構被破(po)壞了(le)，正極板的(de)多孔被電(dian)(dian)池極板的(de)壓力(li)壓實了(le)，就(jiu)降低了(le)參(can)與反應的(de)真實面積，電(dian)(dian)池容量(liang)就(jiu)下降了(le)。

      這樣，防止過放電(dian)就(jiu)是控制(zhi)正極板軟(ruan)化的重要(yao)措施。而這個靠(kao)的是控制(zhi)器的欠(qian)壓(ya)保護(hu)。如果(guo)欠(qian)壓(ya)保護(hu)電(dian)壓(ya)過低，電(dian)池就(jiu)會出(chu)現過放電(dian)，一(yi)些α－PbO2參與放電(dian)，就(jiu)會出(chu)現正極板軟(ruan)化。

      放(fang)(fang)電(dian)(dian)(dian)的(de)(de)時候，如果連續放(fang)(fang)電(dian)(dian)(dian)電(dian)(dian)(dian)流比(bi)較(jiao)大，深(shen)層的(de)(de)β－PbO2來不及(ji)參(can)(can)與(yu)放(fang)(fang)電(dian)(dian)(dian)反應(ying)，外層的(de)(de)α－PbO2就要參(can)(can)與(yu)放(fang)(fang)電(dian)(dian)(dian)反應(ying)，這樣，也(ye)會形成(cheng)正(zheng)極板軟化(hua)。所以(yi)控制器中的(de)(de)限流參(can)(can)數也(ye)浮(fu)充重要。電(dian)(dian)(dian)摩的(de)(de)放(fang)(fang)電(dian)(dian)(dian)電(dian)(dian)(dian)流相對比(bi)較(jiao)大，差不多在(zai)1C左右(you)放(fang)(fang)電(dian)(dian)(dian)，加上放(fang)(fang)電(dian)(dian)(dian)深(shen)度相對比(bi)較(jiao)深(shen)，所以(yi)非常容易產生正(zheng)極板軟化(hua)。

      每(mei)次放電，或(huo)多(duo)或(huo)少的(de)總(zong)要有一點點α－PbO2參與反(fan)應(ying)。所以，一個正常使用的(de)電池(chi)，在不(bu)失水也(ye)不(bu)硫化，也(ye)沒有過(guo)放電的(de)情況下，電池(chi)的(de)壽命就取決(jue)于正極板軟化。

      五、電池均衡問(wen)題

      電池不均衡主(zhu)要有(you)2中表現形式，其一是某(mou)單只電池容量低(di)(di)，其二是電池荷電容量低(di)(di)。第(di)二種(zhong)情況是說(shuo)該(gai)(gai)電池的容量并不抵，但是該(gai)(gai)電池沒有(you)充滿電。

      第一種情(qing)況(kuang)是該電(dian)(dian)(dian)(dian)池放(fang)電(dian)(dian)(dian)(dian)的時候，提(ti)前反應電(dian)(dian)(dian)(dian)壓(ya)下降的快(kuai)，充(chong)電(dian)(dian)(dian)(dian)的時候電(dian)(dian)(dian)(dian)壓(ya)上升也快(kuai)。第二種情(qing)況(kuang)是充(chong)電(dian)(dian)(dian)(dian)荷放(fang)電(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)池的電(dian)(dian)(dian)(dian)壓(ya)都低。

      其(qi)縮短(duan)電池壽命(ming)的原因(yin)如下(xia)：

      1、充(chong)電(dian)時(shi)電(dian)壓高的(de)電(dian)池(chi)(chi)會(hui)增加失水，電(dian)壓低的(de)電(dian)池(chi)(chi)會(hui)欠充(chong)電(dian)；

      2、放電(dian)(dian)的時候，電(dian)(dian)壓低的會出現過(guo)放電(dian)(dian)，形成電(dian)(dian)池(chi)正極板軟化。

      這(zhe)樣，容量低的(de)(de)電(dian)(dian)池在(zai)每次放電(dian)(dian)的(de)(de)時候放電(dian)(dian)深度比其他電(dian)(dian)池深度深，所(suo)以正極板軟化的(de)(de)快。二充電(dian)(dian)電(dian)(dian)壓高的(de)(de)失水，充電(dian)(dian)電(dian)(dian)壓低的(de)(de)欠(qian)充電(dian)(dian)。如(ru)果一只電(dian)(dian)池荷(he)電(dian)(dian)少(shao)，就(jiu)(jiu)存在(zai)充電(dian)(dian)少(shao)，放電(dian)(dian)深的(de)(de)問題。這(zhe)樣該電(dian)(dian)池就(jiu)(jiu)會同時產生正極板軟化荷(he)硫化的(de)(de)問題。

      產(chan)生電池不均(jun)衡的原因(yin)如下：

      1、對(dui)串連電池(chi)組(zu)的組(zu)配不好，存(cun)在(zai)著容量差和(he)開路電壓差，這是原(yuan)始就有(you)誤差的問(wen)題；

      2、電池開閥壓有差別，失水不同，形(xing)成后天電池的容量差；

      3、電池(chi)的自放電不同，逐(zhu)步形(xing)成荷電容量的差異；

      4、失(shi)水不同，形成(cheng)電池實際的(de)硫酸比重不同，形成(cheng)開路電壓(ya)差；

      5、電池壽命差，在(zai)后期反應一只電池容量下降，影響其(qi)他(ta)電池的正常(chang)狀(zhuang)態。

      要改進電池的(de)不均衡問題(ti)(ti)(ti)，首先就要改善電池在制(zhi)造期間(jian)的(de)工(gong)藝一致性問題(ti)(ti)(ti)。這也是(shi)國內(nei)多(duo)數電池制(zhi)造商的(de)主要問題(ti)(ti)(ti)。例如，最(zui)好(hao)的(de)電池制(zhi)造商的(de)板柵是(shi)采用壓(ya)鑄(zhu)的(de)，而國內(nei)相當多(duo)的(de)電池制(zhi)造商連鑄(zhu)板機都沒有(you)，還是(shi)手(shou)工(gong)澆鑄(zhu)。

      六、是(shi)熱(re)失控

      密封(feng)電池(chi)(chi)的(de)最基本(ben)原理之一就是正極板(ban)(ban)析(xi)氧以后，氧氣(qi)直(zhi)接(jie)到負(fu)極板(ban)(ban)，被負(fu)極板(ban)(ban)吸收而還原為水(shui)，考核電池(chi)(chi)這個技術指標(biao)的(de)參數(shu)叫(jiao)做“密封(feng)反應效率”，這種(zhong)現(xian)(xian)象叫(jiao)做“氧循(xun)環”。這樣，電池(chi)(chi)的(de)失(shi)水(shui)很少，實現(xian)(xian)了(le)“免(mian)維護”，就是免(mian)加水(shui)。為此，都要求負(fu)極板(ban)(ban)容量做的(de)比正極板(ban)(ban)容量大一些，叫(jiao)做負(fu)極過渡。

      電池(chi)在充入電量達到70％以后，電池(chi)的極化電壓相對比較高，充電的副反應(ying)開始逐(zhu)步增加。電解(jie)水開始了(le)。

      在充(chong)電(dian)的單格電(dian)壓達到2.35V以(yi)后(hou)，首先(xian)正極(ji)板(ban)析(xi)(xi)氧，在達到2.42V以(yi)后(hou)，負極(ji)板(ban)開始析(xi)(xi)氫(qing)。這時(shi)候充(chong)電(dian)的電(dian)能轉變為化學能減(jian)少，轉變為電(dian)解水(shui)的能量增加。充(chong)電(dian)過程(cheng)的是否析(xi)(xi)氣取決(jue)于充(chong)電(dian)電(dian)壓，析(xi)(xi)氣量取決(jue)于達到析(xi)(xi)氣電(dian)壓以(yi)后(hou)的充(chong)電(dian)電(dian)流。

      所以，在(zai)充電(dian)(dian)(dian)過程中(zhong)，充電(dian)(dian)(dian)電(dian)(dian)(dian)壓(ya)(ya)在(zai)進(jin)入恒壓(ya)(ya)以后，電(dian)(dian)(dian)壓(ya)(ya)開(kai)始(shi)接近于最(zui)高，充電(dian)(dian)(dian)電(dian)(dian)(dian)流(liu)也保持(chi)限流(liu)值。這時(shi)候析氣量(liang)最(zui)大。在(zai)進(jin)入恒壓(ya)(ya)以后，充電(dian)(dian)(dian)電(dian)(dian)(dian)流(liu)應(ying)該(gai)逐(zhu)步(bu)下降(jiang)，析氣量(liang)也應(ying)該(gai)逐(zhu)步(bu)下降(jiang)。

      充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)本身是放熱反(fan)應，一(yi)(yi)般電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)的熱設計是可(ke)以控(kong)制(zhi)溫升(sheng)(sheng)的。在電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)大(da)量析氣以后，氧氣在負極板(ban)復合(he)為水，發(fa)熱量遠遠大(da)于充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)時(shi)的發(fa)熱。密(mi)封電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)希望負極板(ban)具(ju)有(you)良好(hao)的氧循(xun)環能力，但是，氧循(xun)環也(ye)會(hui)產生發(fa)熱。所以，氧循(xun)環是一(yi)(yi)把雙刃劍，好(hao)處是減少了(le)水損(sun)(sun)失(shi)，壞(huai)處是電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)會(hui)發(fa)熱。如果(guo)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)發(fa)熱，在恒壓充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)的條件下，氧循(xun)環電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)(liu)也(ye)參(can)與了(le)充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)(liu)，所以充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)(liu)下降(jiang)速(su)率下降(jiang)。而(er)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)發(fa)熱，會(hui)引起充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)(liu)下降(jiang)速(su)率降(jiang)低，甚(shen)至會(hui)引起電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)(liu)反(fan)升(sheng)(sheng)。而(er)充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)(liu)在電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)發(fa)熱的作用下，一(yi)(yi)旦電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)(liu)反(fan)升(sheng)(sheng)，又增加了(le)發(fa)熱。這樣，充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)(liu)一(yi)(yi)直會(hui)上(shang)升(sheng)(sheng)到限流(liu)(liu)值。電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)發(fa)高(gao)熱，并且(qie)積累熱，一(yi)(yi)直到電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)外殼發(fa)生熱軟化變形(xing)。而(er)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)的熱變形(xing)時(shi)，內(nei)部氣壓高(gao)，所以呈現電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)時(shi)鼓(gu)脹的。這就(jiu)是電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)熱失(shi)控(kong)而(er)損(sun)(sun)壞(huai)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)。電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)一(yi)(yi)旦出現嚴重鼓(gu)脹，漏(lou)酸和漏(lou)氣的問題(ti)也(ye)出現了(le)，電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)會(hui)出現急性失(shi)效。

      誘(you)發電(dian)(dian)池(chi)鼓脹的原因有很多。如果充(chong)(chong)(chong)電(dian)(dian)電(dian)(dian)壓高，析(xi)氣量大，會(hui)(hui)產生(sheng)熱(re)(re)失控(kong)(kong)。如果某一組電(dian)(dian)池(chi)或者某一個單格電(dian)(dian)池(chi)發生(sheng)嚴重落后，而充(chong)(chong)(chong)電(dian)(dian)的恒壓值不變(bian)，其他(ta)的單格電(dian)(dian)池(chi)也(ye)會(hui)(hui)出現充(chong)(chong)(chong)電(dian)(dian)電(dian)(dian)壓相對過高，也(ye)會(hui)(hui)產生(sheng)熱(re)(re)失控(kong)(kong)問題。

      七、電池異常故障

      為(wei)了增(zeng)加電(dian)(dian)池(chi)(chi)(chi)的(de)容(rong)量(liang)，目前電(dian)(dian)動自行車電(dian)(dian)池(chi)(chi)(chi)的(de)隔(ge)(ge)板相對比其他電(dian)(dian)池(chi)(chi)(chi)的(de)隔(ge)(ge)板薄一些(xie)，負(fu)極板的(de)硫(liu)酸(suan)(suan)鉛(qian)(qian)結晶(jing)長大，充電(dian)(dian)以(yi)后(hou)出(chu)現(xian)(xian)(xian)(xian)少量(liang)硫(liu)酸(suan)(suan)鉛(qian)(qian)遺(yi)留在隔(ge)(ge)板中，遺(yi)留在隔(ge)(ge)板中的(de)硫(liu)酸(suan)(suan)鉛(qian)(qian)一旦(dan)被還(huan)原稱(cheng)為(wei)鉛(qian)(qian)，積累(lei)多了，電(dian)(dian)池(chi)(chi)(chi)就會(hui)出(chu)現(xian)(xian)(xian)(xian)微(wei)(wei)短路(lu)。這種現(xian)(xian)(xian)(xian)象(xiang)叫(jiao)做(zuo)“鉛(qian)(qian)枝搭橋”。產(chan)生這種微(wei)(wei)短路(lu)，輕的(de)產(chan)生該單格(ge)電(dian)(dian)壓落后(hou)，嚴重(zhong)(zhong)的(de)時候會(hui)出(chu)現(xian)(xian)(xian)(xian)單格(ge)短路(lu)。這種現(xian)(xian)(xian)(xian)象(xiang)不僅(jin)僅(jin)出(chu)現(xian)(xian)(xian)(xian)在膠體(ti)電(dian)(dian)池(chi)(chi)(chi)中，在普通(tong)的(de)AGM電(dian)(dian)池(chi)(chi)(chi)中也(ye)會(hui)出(chu)現(xian)(xian)(xian)(xian)。一旦(dan)出(chu)現(xian)(xian)(xian)(xian)電(dian)(dian)池(chi)(chi)(chi)的(de)單格(ge)嚴重(zhong)(zhong)落后(hou)，電(dian)(dian)池(chi)(chi)(chi)還(huan)很容(rong)易出(chu)現(xian)(xian)(xian)(xian)熱失控現(xian)(xian)(xian)(xian)象(xiang)。

      還(huan)有就(jiu)(jiu)(jiu)是(shi)極(ji)群組(zu)(zu)裝(zhuang)虛(xu)(xu)(xu)焊(han)(han)問(wen)題。容(rong)易產(chan)生虛(xu)(xu)(xu)焊(han)(han)的(de)(de)地方(fang)是(shi)極(ji)板。而(er)每個電(dian)(dian)(dian)池(chi)(chi)的(de)(de)單(dan)格(ge)(ge)(ge)有15片極(ji)板，就(jiu)(jiu)(jiu)是(shi)15個焊(han)(han)點，一(yi)(yi)個電(dian)(dian)(dian)池(chi)(chi)有6個單(dan)格(ge)(ge)(ge)，就(jiu)(jiu)(jiu)有90個焊(han)(han)點，一(yi)(yi)組(zu)(zu)電(dian)(dian)(dian)池(chi)(chi)由4個電(dian)(dian)(dian)池(chi)(chi)組(zu)(zu)成(cheng)，就(jiu)(jiu)(jiu)要(yao)360個焊(han)(han)點。如果一(yi)(yi)個焊(han)(han)點存(cun)在(zai)虛(xu)(xu)(xu)焊(han)(han)，該單(dan)格(ge)(ge)(ge)容(rong)量就(jiu)(jiu)(jiu)下降，進而(er)該單(dan)格(ge)(ge)(ge)形成(cheng)電(dian)(dian)(dian)池(chi)(chi)落后，形成(cheng)整個電(dian)(dian)(dian)池(chi)(chi)都落后，電(dian)(dian)(dian)池(chi)(chi)就(jiu)(jiu)(jiu)會(hui)形成(cheng)嚴重的(de)(de)不(bu)均(jun)衡。就(jiu)(jiu)(jiu)會(hui)使(shi)改組(zu)(zu)電(dian)(dian)(dian)池(chi)(chi)提前失效。如果虛(xu)(xu)(xu)焊(han)(han)率達到萬(wan)分之一(yi)(yi)，平(ping)均(jun)每37組(zu)(zu)電(dian)(dian)(dian)池(chi)(chi)就(jiu)(jiu)(jiu)有一(yi)(yi)組(zu)(zu)電(dian)(dian)(dian)池(chi)(chi)存(cun)在(zai)這虛(xu)(xu)(xu)焊(han)(han)，這是(shi)絕(jue)對不(bu)能夠允(yun)許的(de)(de)。而(er)鉛鈣合金的(de)(de)電(dian)(dian)(dian)池(chi)(chi)，在(zai)焊(han)(han)接的(de)(de)時候會(hui)析出鈣而(er)掩蓋虛(xu)(xu)(xu)焊(han)(han)問(wen)題，這樣(yang)，很多電(dian)(dian)(dian)池(chi)(chi)制造(zao)商寧愿還(huan)采(cai)(cai)用(yong)低銻合金的(de)(de)板柵而(er)沒有采(cai)(cai)用(yong)簡單(dan)的(de)(de)鉛鈣合金。