電動自行車（以下簡稱“EB”）產業的興起，對充電器提出了高要求。目前EB所配置的充電器，多屬(shu)于(yu)傳統(tong)的三(san)段(duan)(duan)式充(chong)(chong)電(dian)(dian)(dian)(dian)器(qi)，三(san)段(duan)(duan)式充(chong)(chong)電(dian)(dian)(dian)(dian)器(qi)的充(chong)(chong)電(dian)(dian)(dian)(dian)模(mo)式是(shi)將充(chong)(chong)電(dian)(dian)(dian)(dian)過程分為恒(heng)(heng)流(liu)、恒(heng)(heng)壓(ya)(ya)、浮充(chong)(chong)三(san)個充(chong)(chong)電(dian)(dian)(dian)(dian)階段(duan)(duan)，以我國EB采用較多的36V12Ah鉛酸(suan)蓄電(dian)(dian)(dian)(dian)池(chi)(chi)組(zu)為例，第一階段(duan)(duan)以1.8A的恒(heng)(heng)定電(dian)(dian)(dian)(dian)流(liu)將電(dian)(dian)(dian)(dian)池(chi)(chi)充(chong)(chong)到(dao)約(yue)44.4V；第二階段(duan)(duan)將充(chong)(chong)電(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)流(liu)減小至約(yue)0.3A，再次將電(dian)(dian)(dian)(dian)池(chi)(chi)電(dian)(dian)(dian)(dian)壓(ya)(ya)充(chong)(chong)到(dao)44.4V；第三(san)階段(duan)(duan)將電(dian)(dian)(dian)(dian)壓(ya)(ya)降至約(yue)41.4V，電(dian)(dian)(dian)(dian)流(liu)減至約(yue)50MA對電(dian)(dian)(dian)(dian)池(chi)(chi)進(jin)行浮充(chong)(chong)。

　　從幾年來的使用情況看，三段式充電器暴露了(le)一(yi)些問(wen)題。以下仍以36V12Ah鉛酸蓄電池組為例，談談三段式(shi)充電器的缺陷(xian)和解決方案。

　　三段式充電器(qi)忽略(lve)了電池(chi)的負溫度特性

　　三段式充電(dian)(dian)器充電(dian)(dian)參(can)數的(de)設定除受所配電(dian)(dian)池(chi)單體(ti)極板面積大小(xiao)、電(dian)(dian)極特性、電(dian)(dian)解液(ye)密度(du)等因(yin)素影響(xiang)外，還受蓄(xu)電(dian)(dian)池(chi)的(de)環境溫度(du)的(de)影響(xiang)。

　　雖(sui)然一直以來，人們都(dou)明白電化學(xue)的(de)溫度效應(ying)是不能回(hui)避的(de)，但(dan)卻在(zai)充電器問題上忽略(lve)了。原因可以有很(hen)多，但(dan)特(te)別(bie)應(ying)在(zai)此指出的(de)是：過去人們對蓄(xu)電池容量、壽命與溫度之間關(guan)系(xi)的(de)感觸和認識從來沒(mei)有象今天這(zhe)樣直接(jie)和具體，須知(zhi)，這(zhe)是千萬個EB用(yong)戶(hu)參與了“實驗”的(de)結果。

　　在我(wo)國幾乎所有(you)的(de)(de)地區，使用無溫度補償(chang)的(de)(de)充電(dian)(dian)器(qi)，都(dou)會(hui)對(dui)電(dian)(dian)池(chi)造(zao)成(cheng)損害(hai)。夏季過充，冬季欠(qian)充，過充和(he)欠(qian)充容(rong)易造(zao)成(cheng)電(dian)(dian)池(chi)失(shi)水(shui)和(he)硫酸(suan)(suan)(suan)鹽(yan)化(hua)，電(dian)(dian)池(chi)失(shi)水(shui)后，硫酸(suan)(suan)(suan)濃度提高，加劇了板極腐蝕(shi)，就更(geng)容(rong)易產生硫酸(suan)(suan)(suan)鹽(yan)化(hua)，硫酸(suan)(suan)(suan)鹽(yan)化(hua)的(de)(de)電(dian)(dian)池(chi)表(biao)現為更(geng)容(rong)易失(shi)水(shui)。這是(shi)一(yi)種連鎖反(fan)應。鉛酸(suan)(suan)(suan)電(dian)(dian)池(chi)硫酸(suan)(suan)(suan)鹽(yan)化(hua)是(shi)影(ying)響EB續駛(shi)里程(cheng)和(he)電(dian)(dian)池(chi)壽命的(de)(de)重要因素。

　　無溫度補嘗(chang)的(de)充電(dian)器(qi)究竟對電(dian)池(chi)(chi)的(de)損害(hai)有多(duo)大，目前還缺(que)少(shao)實(shi)驗(yan)數(shu)據，對蓄電(dian)池(chi)(chi)進行定量(liang)分(fen)析(xi)要比定性分(fen)析(xi)復雜困(kun)難得多(duo)，但以下的(de)數(shu)據可以參考(kao)：EB標準規定，鉛酸蓄電(dian)池(chi)(chi)的(de)循環次(ci)數(shu)不(bu)得不(bu)少(shao)于(yu)350次(ci)，但實(shi)際上有相(xiang)當多(duo)的(de)電(dian)池(chi)(chi)使(shi)用時間不(bu)到8個月，即循還次(ci)數(shu)不(bu)足(zu)240次(ci)。

　　充電(dian)器增加溫度補償(chang)功能并不困難，如只要將原基準電(dian)壓改為具有負溫度系數特性的基準電(dian)壓，一般就(jiu)可以了。

　　三段式充電模式缺少(shao)修補(bu)性充電環節

　　三段(duan)(duan)式(shi)充電(dian)模式(shi)的(de)(de)恒(heng)流――恒(heng)壓(ya)――浮充三個(ge)充電(dian)階(jie)段(duan)(duan)，都是(shi)圍繞怎樣充滿電(dian)池(chi)來設(she)計的(de)(de)，因此，這三個(ge)充電(dian)階(jie)段(duan)(duan)占用了全部充電(dian)時(shi)間，如36V12Ah電(dian)池(chi)組的(de)(de)充電(dian)電(dian)流通常被設(she)定為18A，有公式(shi)：12(安時(shi)）×1.2（效率(lv)）÷8（小(xiao)時(shi)）=1.8A。恰好能(neng)在(zai)標準規定的(de)(de)8h內將電(dian)池(chi)充滿，設(she)計時(shi)就(jiu)沒打算留出修補電(dian)池(chi)的(de)(de)時(shi)間，更何況三段(duan)(duan)式(shi)充電(dian)器一般也不具備修補電(dian)池(chi)的(de)(de)功能(neng)。

　　產業界(jie)向(xiang)來有(you)人認(ren)為：我國的(de)(de)(de)(de)(de)(de)EB以采(cai)用(yong)鉛酸蓄(xu)電(dian)(dian)(dian)池(chi)為主(zhu)，并且采(cai)取的(de)(de)(de)(de)(de)(de)是全(quan)動(dong)力模式，如電(dian)(dian)(dian)池(chi)長期不能(neng)(neng)達標(biao)，我國的(de)(de)(de)(de)(de)(de)EB產業將可能(neng)(neng)有(you)再次夭折(zhe)的(de)(de)(de)(de)(de)(de)危險。但技(ji)術(shu)界(jie)對(dui)(dui)此問(wen)(wen)題(ti)的(de)(de)(de)(de)(de)(de)認(ren)識是：要(yao)想鉛酸蓄(xu)電(dian)(dian)(dian)池(chi)達標(biao)，除(chu)有(you)待于電(dian)(dian)(dian)池(chi)本(ben)身的(de)(de)(de)(de)(de)(de)技(ji)術(shu)進(jin)(jin)步外，采(cai)用(yong)充(chong)(chong)電(dian)(dian)(dian)與修補功(gong)能(neng)(neng)兼備的(de)(de)(de)(de)(de)(de)多功(gong)能(neng)(neng)充(chong)(chong)電(dian)(dian)(dian)器(qi)是解決問(wen)(wen)題(ti)的(de)(de)(de)(de)(de)(de)有(you)效途徑。因此，我們建議立即從以下兩(liang)方面入手對(dui)(dui)EB充(chong)(chong)電(dian)(dian)(dian)器(qi)進(jin)(jin)行(xing)技(ji)術(shu)改(gai)造。一是將36V12Ah電(dian)(dian)(dian)池(chi)組的(de)(de)(de)(de)(de)(de)充(chong)(chong)電(dian)(dian)(dian)電(dian)(dian)(dian)流從1.8A提高(gao)到3A以上，用(yong)約4h的(de)(de)(de)(de)(de)(de)時間(jian)對(dui)(dui)電(dian)(dian)(dian)池(chi)進(jin)(jin)行(xing)常規性(xing)充(chong)(chong)電(dian)(dian)(dian)，留出4h以上時間(jian)對(dui)(dui)電(dian)(dian)(dian)池(chi)進(jin)(jin)行(xing)修補性(xing)充(chong)(chong)電(dian)(dian)(dian)；二是給充(chong)(chong)電(dian)(dian)(dian)器(qi)增加(jia)對(dui)(dui)電(dian)(dian)(dian)池(chi)進(jin)(jin)行(xing)修補性(xing)充(chong)(chong)電(dian)(dian)(dian)的(de)(de)(de)(de)(de)(de)功(gong)能(neng)(neng)。

　　關于充(chong)電的波形和(he)頻率(lv)

　　充(chong)(chong)(chong)電(dian)(dian)器賴以對電(dian)(dian)池產(chan)生(sheng)影響的是(shi)充(chong)(chong)(chong)電(dian)(dian)電(dian)(dian)壓(ya)、電(dian)(dian)流及其(qi)波(bo)形(xing)和(he)頻(pin)率，其(qi)中，充(chong)(chong)(chong)電(dian)(dian)電(dian)(dian)壓(ya)主要與(yu)(yu)電(dian)(dian)池充(chong)(chong)(chong)得(de)滿(man)不(bu)滿(man)有關，充(chong)(chong)(chong)電(dian)(dian)電(dian)(dian)流主要與(yu)(yu)充(chong)(chong)(chong)電(dian)(dian)充(chong)(chong)(chong)得(de)快(kuai)(kuai)不(bu)快(kuai)(kuai)有關，而充(chong)(chong)(chong)電(dian)(dian)的波(bo)形(xing)和(he)頻(pin)率則主要與(yu)(yu)充(chong)(chong)(chong)電(dian)(dian)充(chong)(chong)(chong)得(de)好(hao)好(hao)不(bu)好(hao)有關，這(zhe)里的“好(hao)不(bu)好(hao)”指得(de)是(shi)電(dian)(dian)池的容(rong)量和(he)壽命(ming)。實踐(jian)證明，以上三者雖各有側重，但其(qi)關系是(shi)相輔相成、不(bu)可忽略的。

　　充(chong)電器屬于電源(yuan)技(ji)術領域，在充(chong)電過(guo)程中強調(diao)(diao)波形和(he)頻(pin)率的(de)(de)作用是開(kai)關電源(yuan)出(chu)現以后的(de)(de)事，而三(san)段(duan)式(shi)充(chong)電模式(shi)出(chu)現在線性電源(yuan)時期，因此(ci)，三(san)段(duan)式(shi)充(chong)電模式(shi)偏重于充(chong)電電壓(ya)和(he)電流，缺少充(chong)電波形和(he)頻(pin)率方面的(de)(de)內容(rong)是情有可原的(de)(de)。現在，EB配置(zhi)的(de)(de)充(chong)電器全都是用開(kai)關電源(yuan)技(ji)術設(she)計(ji)的(de)(de)，但卻(que)仍采用三(san)段(duan)式(shi)充(chong)電模式(shi)，這顯然(ran)是不相宜的(de)(de)，據我們調(diao)(diao)查和(he)檢(jian)測(ce)，目前的(de)(de)EB充(chong)電器還不同程度(du)地存(cun)在以下問題：

　　（1）輸出紋波太小。有(you)的(de)竟只有(you)50mV，顯然這是將(jiang)充電(dian)器當成穩(wen)壓(ya)電(dian)源來(lai)做了(le)，也許(xu)這種紋波可以用(yong)來(lai)給鋰(li)離子電(dian)池(chi)充電(dian)，但對(dui)于36V鉛酸蓄電(dian)池(chi)來(lai)說，充電(dian)脈沖的(de)幅值應以1-2V為好。

　　（2）輸出連(lian)(lian)續三角(jiao)波(bo)(bo)。這(zhe)(zhe)通(tong)常(chang)(chang)是(shi)正激式(shi)開關(guan)電(dian)(dian)(dian)源(yuan)(yuan)(yuan)充(chong)電(dian)(dian)(dian)器(qi)才有的(de)波(bo)(bo)形(xing)，由于極化(hua)現象的(de)存在，蓄電(dian)(dian)(dian)池(chi)(chi)忌諱用(yong)直流充(chong)電(dian)(dian)(dian)，包括連(lian)(lian)續三角(jiao)波(bo)(bo)。常(chang)(chang)規性充(chong)電(dian)(dian)(dian)的(de)最好波(bo)(bo)形(xing)是(shi)單端反激式(shi)開關(guan)電(dian)(dian)(dian)源(yuan)(yuan)(yuan)通(tong)常(chang)(chang)所輸出的(de)下(xia)降型(xing)脈沖(chong)，尤其是(shi)緊接(jie)脈沖(chong)之后存在的(de)一(yi)段(duan)休止時間(jian)，還可(ke)以(yi)消除鉛酸蓄電(dian)(dian)(dian)池(chi)(chi)因充(chong)電(dian)(dian)(dian)而產生(sheng)的(de)電(dian)(dian)(dian)化(hua)學(xue)極化(hua)；比較而言，正激式(shi)開關(guan)電(dian)(dian)(dian)源(yuan)(yuan)(yuan)充(chong)電(dian)(dian)(dian)器(qi)的(de)溫升雖然可(ke)以(yi)做得低(di)一(yi)些，但其輸出波(bo)(bo)形(xing)不如反激式(shi)電(dian)(dian)(dian)源(yuan)(yuan)(yuan)，不過(guo)這(zhe)(zhe)可(ke)以(yi)通(tong)過(guo)調整(zheng)其輸出三角(jiao)波(bo)(bo)的(de)占空比來加以(yi)彌補。

　　（3）在(zai)充(chong)(chong)(chong)電(dian)(dian)器(qi)與電(dian)(dian)池(chi)(chi)之(zhi)間串(chuan)聯有一(yi)(yi)二極管。其目的(de)可能(neng)是(shi)為(wei)了(le)防止電(dian)(dian)池(chi)(chi)通過充(chong)(chong)(chong)電(dian)(dian)器(qi)放(fang)(fang)電(dian)(dian)，但(dan)這樣做是(shi)錯誤的(de)。充(chong)(chong)(chong)電(dian)(dian)就(jiu)是(shi)需(xu)要又充(chong)(chong)(chong)電(dian)(dian)又放(fang)(fang)，邊充(chong)(chong)(chong)邊放(fang)(fang)，充(chong)(chong)(chong)多放(fang)(fang)少，哪怕(pa)放(fang)(fang)電(dian)(dian)只(zhi)有充(chong)(chong)(chong)電(dian)(dian)的(de)百(bai)分之(zhi)一(yi)(yi)，也將(jiang)會對抑制電(dian)(dian)池(chi)(chi)氣化和(he)抬高氣化電(dian)(dian)壓等產(chan)生不可替(ti)代的(de)作用(yong)(yong)。應該認(ren)識到，如能(neng)在(zai)每(mei)一(yi)(yi)常規性充(chong)(chong)(chong)電(dian)(dian)周(zhou)期留出(chu)(chu)幾微(wei)秒和(he)在(zai)修補性充(chong)(chong)(chong)電(dian)(dian)周(zhou)期留出(chu)(chu)幾秒鐘(zhong)用(yong)(yong)來放(fang)(fang)電(dian)(dian)，對消(xiao)除鉛(qian)酸蓄電(dian)(dian)池(chi)(chi)在(zai)充(chong)(chong)(chong)電(dian)(dian)時產(chan)生的(de)電(dian)(dian)化學極化和(he)濃差極化，從而增(zeng)加(jia)和(he)延長電(dian)(dian)池(chi)(chi)的(de)容量和(he)壽命將(jiang)會有決定性意義(yi)。

（4）充(chong)(chong)電(dian)(dian)(dian)(dian)頻率(lv)單(dan)調。一個優秀(xiu)的(de)充(chong)(chong)電(dian)(dian)(dian)(dian)器必須具有(you)多(duo)種(zhong)充(chong)(chong)電(dian)(dian)(dian)(dian)模式：脈(mo)沖充(chong)(chong)電(dian)(dian)(dian)(dian)、負脈(mo)沖激(ji)活、變頻充(chong)(chong)電(dian)(dian)(dian)(dian)等模式，只有(you)具備這(zhe)些技術的(de)充(chong)(chong)電(dian)(dian)(dian)(dian)器才能(neng)(neng)有(you)效地去除電(dian)(dian)(dian)(dian)解液(ye)濃度極差、板柵硫(liu)酸鹽化和極化現象。脈(mo)沖充(chong)(chong)電(dian)(dian)(dian)(dian)、高(gao)頻充(chong)(chong)電(dian)(dian)(dian)(dian)以及變頻充(chong)(chong)電(dian)(dian)(dian)(dian)等充(chong)(chong)電(dian)(dian)(dian)(dian)技術，正在被越來越多(duo)地應用在充(chong)(chong)電(dian)(dian)(dian)(dian)器上，可(ke)以預期，一種(zhong)兼有(you)常規性充(chong)(chong)電(dian)(dian)(dian)(dian)功能(neng)(neng)和修補性充(chong)(chong)電(dian)(dian)(dian)(dian)功能(neng)(neng)的(de)多(duo)功能(neng)(neng)充(chong)(chong)電(dian)(dian)(dian)(dian)器必將(jiang)替代功能(neng)(neng)單(dan)一的(de)三段式充(chong)(chong)電(dian)(dian)(dian)(dian)器而成為EB的(de)主流。

　　一(yi)種實用的(de)EB多功(gong)能充電器(qi)的(de)充電模式和參數

　　如將(jiang)凡包(bao)含常規性(xing)充電(dian)(dian)(dian)(dian)功(gong)(gong)能和修(xiu)補性(xing)充電(dian)(dian)(dian)(dian)功(gong)(gong)能的(de)充電(dian)(dian)(dian)(dian)器(qi)統稱為多(duo)功(gong)(gong)能充電(dian)(dian)(dian)(dian)器(qi)，那么根(gen)據以(yi)(yi)兩種(zhong)充電(dian)(dian)(dian)(dian)功(gong)(gong)能結合方(fang)式(shi)的(de)不同，可以(yi)(yi)設計(ji)出(chu)多(duo)種(zhong)模式(shi)的(de)多(duo)功(gong)(gong)能充電(dian)(dian)(dian)(dian)器(qi)，但從EB的(de)適用角度考慮，還是(shi)將(jiang)以(yi)(yi)上兩種(zhong)充電(dian)(dian)(dian)(dian)功(gong)(gong)能分開來設計(ji)好(hao)，即將(jiang)有限的(de)充電(dian)(dian)(dian)(dian)時間劃分為兩個充電(dian)(dian)(dian)(dian)時間段，前段時間用來完成常規性(xing)充電(dian)(dian)(dian)(dian)，后段時間用來進行修(xiu)補性(xing)充電(dian)(dian)(dian)(dian)。以(yi)(yi)下仍以(yi)(yi)36V 12Ah鉛酸蓄電(dian)(dian)(dian)(dian)池組(zu)為例，介紹一種(zhong)實(shi)用的(de)多(duo)功(gong)(gong)能充電(dian)(dian)(dian)(dian)器(qi)的(de)充電(dian)(dian)(dian)(dian)模式(shi)和參數。

　　4.1常規性充(chong)電階段(duan)

　　（1）電(dian)源(yuan)類(lei)型(xing)：單端反(fan)激式開關電(dian)源(yuan)；

　　（2）滿輸出充電(dian)頻率(lv)(lv)：25kHz，即充電(dian)電(dian)源3A時的電(dian)源工作頻率(lv)(lv)；

　　（3）充電波形：下降型三角脈沖；

　　（4）脈(mo)沖幅度：約1.6V；

　　（5）脈沖最(zui)大寬度：約(yue)25μs；

　　（6）充電休(xiu)止(zhi)時(shi)間：約(yue)15μs；

　　（7）放電(dian)電(dian)流：約50mA；

　　（8）充電(dian)平均電(dian)流(liu)：3A；

　　（9）充(chong)電峰(feng)值電流：約(yue)10A；

　　（10）充電(dian)時間：約4h，即(ji)充電(dian)4h后，電(dian)池(chi)電(dian)壓應上升到43.2V（常(chang)溫(wen)），容量已(yi)達75%以上；

　　（11）減流轉(zhuan)折電(dian)壓：常(chang)溫下(xia)43.2V，該電(dian)壓為“氣(qi)化點電(dian)壓”，即在用直流充(chong)電(dian)的(de)(de)情況(kuang)下(xia)，此時鉛酸電(dian)池的(de)(de)電(dian)解液已(yi)開始大量(liang)氣(qi)化。以下(xia)轉(zhuan)入(ru)修補性充(chong)電(dian)階(jie)段。

　　4.2修補性充電階段(duan)

　　（1）線(xian)性減流(liu)(liu)及范圍：電(dian)池電(dian)壓上(shang)升到43.2V（常溫）時，充(chong)電(dian)電(dian)流(liu)(liu)開始減小(xiao)，減小(xiao)的速(su)率呈(cheng)線(xian)性，平均充(chong)電(dian)電(dian)流(liu)(liu)從3A最終減為(wei)不小(xiao)于0.3A，或峰值充(chong)電(dian)電(dian)流(liu)(liu)從約10A減為(wei)1A；

　　（2）充電頻率(lv)變(bian)化范圍(wei)：線性減流時，隨(sui)著充電電流的減小，充電頻率(lv)開始上升，其變(bian)化范圍(wei)為25-100kHz；

　　（3）充電(dian)(dian)(dian)(dian)終(zhong)止(zhi)電(dian)(dian)(dian)(dian)壓：該電(dian)(dian)(dian)(dian)壓相當于“氣(qi)化點電(dian)(dian)(dian)(dian)壓”加約1.2V，當電(dian)(dian)(dian)(dian)池電(dian)(dian)(dian)(dian)壓上升至該電(dian)(dian)(dian)(dian)壓時，充電(dian)(dian)(dian)(dian)器終(zhong)止(zhi)充電(dian)(dian)(dian)(dian)；

　　（4）重(zhong)(zhong)起動(dong)電(dian)(dian)壓(ya)：終止(zhi)充(chong)(chong)電(dian)(dian)后，電(dian)(dian)池(chi)電(dian)(dian)壓(ya)下降(jiang)，當降(jiang)至重(zhong)(zhong)起動(dong)電(dian)(dian)壓(ya)時(shi)，充(chong)(chong)電(dian)(dian)器將(jiang)再次(ci)起動(dong)將(jiang)電(dian)(dian)池(chi)充(chong)(chong)到(dao)充(chong)(chong)電(dian)(dian)終止(zhi)電(dian)(dian)壓(ya)，而后充(chong)(chong)電(dian)(dian)終止(zhi)，電(dian)(dian)池(chi)電(dian)(dian)壓(ya)再次(ci)下降(jiang)，充(chong)(chong)電(dian)(dian)將(jiang)循環反重(zhong)(zhong)地進行(xing)下去；

　　（5）充(chong)(chong)(chong)電(dian)終止(zhi)時(shi)間(jian)：終止(zhi)充(chong)(chong)(chong)電(dian)后(hou)，電(dian)池電(dian)壓下降的時(shi)間(jian)起(qi)先較快，約幾秒鐘，隨(sui)著時(shi)間(jian)推移，終止(zhi)充(chong)(chong)(chong)電(dian)的時(shi)間(jian)會越來越長，可達幾分鐘以上；

　　（6）修(xiu)補性(xing)充電的延續時間：4h以上(shang)不限

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