茄子视频APP

茄子视频APP > 技術專欄 > 充電器充電的電池簡稱二次電池

充電器充電的電池簡稱二次電池

和(he)普(pu)通的不可充電的電池相比(bi),可充電(dian)(dian)的(de)電(dian)(dian)池(chi)叫二(er)次(ci)電(dian)(dian)池(chi)。二(er)次(ci)電(dian)(dian)池(chi)能夠反(fan)復運用(yong),符合(he)經濟實用(yong)原則,這是(shi)其最大(da)的(de)優點,自然人們最青睞二(er)次(ci)電(dian)(dian)池(chi)。二(er)次(ci)電(dian)(dian)池(chi)的(de)種類(lei)也不少,就目前(qian)市場上主流產品而言,有(you) 4類電池:鉛酸(LA)電池、鎳鎘(ge)(NiCd)電池、鎳(nie)氫(NiMH)電(dian)池和鋰(li)離子(zi)(Liion )電池。

    1.便攜式電子設備(bei)可選擇的電源系統

    對(dui)便攜(xie)式電(dian)(dian)子設備的(de)(de)生產商來(lai)說,給便攜(xie)式電(dian)(dian)子設備選擇(ze)合適(shi)的(de)(de)電(dian)(dian)池是很(hen)(hen)困(kun)難的(de)(de)。因為電(dian)(dian)池的(de)(de)選擇(ze)會對(dui)設備的(de)(de)功能、型號(hao)、成本造成很(hen)(hen)大的(de)(de)影(ying)響。設計者面對(dui)著很(hen)(hen)多選擇(ze),從簡單的(de)(de)鉛酸電(dian)(dian)池到復雜的(de)(de)集(ji)成了電(dian)(dian)子安全、監(jian)視和(he)充電(dian)(dian)控制電(dian)(dian)路的(de)(de)鋰(li)離子電(dian)(dian)池。

    1)鎳(nie)鎘電池。

    鎳鋼電池工作電壓為12V左右(you),具有優良的大電流放電性(xing)能,可在(zai)一20600C溫度(du)范圍內(nei)工作。與(yu)鉛酸電(dian)(dian)池(chi)相反,這種(zhong)電(dian)(dian)池(chi)過充電(dian)(dian)性能好,可(ke)靠性高(gao)。與(yu)鎳鎘電(dian)(dian)池(chi)類似的(de)堿溶液二次電(dian)(dian)池(chi)還有(you)鐵鎳、鋅鎳、鋅銀、鎘銀等(deng),這類電(dian)(dian)池(chi)有(you)充放電(dian)(dian)周期數(shu)多、工作壽命(ming)長、長期不(bu)用(yong)也不(bu)影響壽命(ming)、可(ke)靠耐用(yong)、容易使用(yong)等(deng)特點,因而有(you)很(hen)大(da)的(de)產(chan)量和(he)應用(yong)空間。總之(zhi)這類電(dian)(dian)池(chi)最大(da)的(de)優點是穩定耐用(yong),缺點是鎘較貴和(he)污(wu)染環境(jing)。

    鎳鎘電池種(zhong)類繁(fan)多,有放置用的(de)大型電池(多數20Ah以上)和(he)小型密封(feng)型電池(chi),6Ah以下的圓柱(zhu)形和(he)扁平形電池,05Ah以下的紐扣式電池(chi)。日本三(san)洋公(gong)司(si)生(sheng)產(chan)402000mAh的(de) 95種(zhong)型號的(de)鎳(nie)鎘電池(chi),按用途(tu)有 8類電(dian)池:一般用(標準型)、 高容量(E型(xing))、 快速充電(dian)用(R型(xing))、 高溫用(yong)(H型(xing))、耐熱用(K型)、 長壽命(C型(xing))、保(bao)護記(ji)憶用(S型(xing))、 扁(bian)平形(KF型(xing))、標準(zhun)型(xing)典型(xing)電池為  AA型,容量為600mAh,尺寸為(wei)142mmX  505mm

質量為(wei) 23克,內阻為12mΩAAA型的容(rong)量為 250mAh,尺寸為(wei)105mm X 445mm,質量為(wei)11克,內阻24Ω。

    鎳鎘電池正極板上的活性物質由氧化鎳粉和石墨粉組成,石墨不參加化學反應,其主要作用是增強導電性。負極板上的活性物質由氧化鋁粉和氧化鐵粉組成,氧化鐵粉的作用是使氧化鋁粉有較高的擴散性,防止結塊,并增加極板的容量。活性物質分別包在穿孔鋼帶中,加壓成型后即成為電池的正負極板。極板間用耐堿的硬橡膠絕緣棍或有孔的聚氯乙烯瓦楞板隔開。電解液通常用氫氧化鉀溶液。與其他電池相比,鎳錫電池的自放電率(電池不使用時失去電荷的速率)適中。鎳鎘電池在使用過程中,如果放電不完全就又充電,下次再放電時,就不能放出全部的電量。比如,放出80%電量后再充足電,該電池只能放出80%的電量,這就是所謂的記憶效應。當然,幾次完整的放電/充電循環將使鎳鎘電池恢復正常工作。

由于鎳鎘電池的記憶效應,若未完全放電,應在充電前將每節電池放電至 1V以下。

2)鎳氫電池。鎳氫電池是生產了幾年的新電池,又稱為貯氫電池。20世紀70年代,荷蘭飛利浦實驗室在研究第一代稀土永磁合金時,試驗了LaNi5的磁性能,競意外地發現了 LaNi5有很好的貯氫性能,但深入研究發現對貯氫合金不適用,因為平衡壓太高,循環壽命太短,進一步研究和改進發現,這些缺點都可克服,從而為發展貯氫電池奠定了技術基礎。

兩者有相同的工作電壓12V,因此這兩種電池有良好的互換性。

鎳氫電池的能量高,為鎳鎘電池的182倍,鉛酸電池的3倍,有良好的充放電性能,可隨充隨放,快充深放,無記憶效應,特別不含鎘、鉛、汞等有害物質,對環境無污染,被稱為綠色電池。

鎳氫電池與鎳鎘電池類似,多種多樣。有圓柱形和扁平形的小電池,有紐扣式電池,也有方形蓄電池組作為動力電池用,容量為1020Ah。日本三洋公司生產的 AA型的容量為1100mAh,尺寸為  142mm X 500mm,質量為27克,AAA型的容量為  650mAh,尺寸為105 mm  X  4 45 mm,質量為  13 g

鎳氫電池具有較好的低溫放電特性,即使在一 200C環境溫度下,采用大電流(以1C放電速率)放電,放出的電量也能達到標稱容量的 85%以上。但是,鎳氫電池在高溫十 400C以上時,蓄電容量將下降5%~10%。這種由于自放電(溫度越高,自放電率越大)而引起的容量損失是可逆的,幾次充放電循環就能恢復到最大容量。

 鎳鎘電池與鎳氫電池的充電過程非常相似,都要求恒流充電。兩者的差別主要在快速充電的終止檢測方法上,以防止電池過充電。充電器對電池進行恒流充電,同時檢測電池的電壓和其他參數。當電池電壓緩慢上升達到一個峰值時,對鎳氫電池快速充電終止,而鎳鎘電池則當電池電壓第一次下降了一個ΔV時終止快速充電。為避免損壞電池,電池溫度過低時不能開始快速充電,電池溫度 Tmin低于 100C時,應轉入涓流充電方式。而電池溫度一旦達到規定數值后,必須立即停止充電。

  3)鋰離子電池。鋰離子電池是繼鎳氫電池后發展的新一代的二次電池。鋰位于元素周期表第一族主族第一位上,是金屬中最輕的元素,有最負的標準電位,組成電池能量密度大和電壓高。鋰離子電池負極電位相對鋰電極為正,正極電位為4OV,該電池的工作電壓高,約36V。高電壓是個優點,一個鋰離子電池相當于三個鎳氫電池或鎳鎘電池,但這也是個缺點,因為移動電話芯片電壓趨向下降,這將挑戰36V 鋰離子電池的應用。鋰離子電池有高的比能量,為鎳氫電池的15倍和鉛酸電池的3倍,放電曲線平穩,自放電率低,循環壽命長,與鎳氫電池一樣,無記憶效應和不污染環境,也為綠色電池。

    鋰離子電池采用卷繞式結構,蓋體設計強化了安全保護功能。對于這種高比能量電池,必須經過規范的安全檢測評估。鎳氫和鎳鎘電池的電解液是水溶液,而鋰離子電池必需用非水性電解液,其電導率低得多,因此電極要大大減薄,有著不同的電極制備工藝,制備又薄又長的正負電極。鋰離子電池同樣有圓柱式、扁平式、紐扣式和動力用電池組。Sony公司的 14500電池容量為 500mAh,尺寸為 143mmX 504mm,質量為19g18650電池的容量為 1350mAh,尺寸為 184mmX 649mm,質量為 40g

    鋰離子電池能夠很好地配合電子產品小型化、袖珍化的發展方向,移動電話和筆記本電腦要求又薄又輕的二次電池,三洋超薄鋰離子電池僅 4mm厚,質量比能量160Wh/kg(比能(neng)量指(zhi)的是單位重量或單位體(ti)積(ji)的能(neng)量。比能(neng)量用Wh/kgWh/L來表示。Wh是(shi)能量的(de)單位,W是瓦、h是小時;kg是千克(重(zhong)量(liang)單位(wei))L是升(體積單位) ),體積比能量360WhL

    鋰(li)離(li)子電(dian)(dian)池易受到過(guo)充電(dian)(dian)、深放(fang)電(dian)(dian)以(yi)及短路的損害(hai)。單體(ti)(ti)鋰(li)離(li)子電(dian)(dian)池的充電(dian)(dian)電(dian)(dian)壓必須嚴格限(xian)制。充電(dian)(dian)速率通常不(bu)超過(guo)1C,最低放電(dian)電(dian)壓(ya)為273OV,如再繼續放電(dian),則會損壞電(dian)池(chi)。鋰離(li)子(zi)電(dian)池(chi)以恒流轉恒壓方式進行充(chong)電(dian)。采用(yong)1C電(dian)流充電(dian)至41V時,充(chong)(chong)電(dian)(dian)器(qi)應立即(ji)轉入恒壓充(chong)(chong)電(dian)(dian),充(chong)(chong)電(dian)(dian)電(dian)(dian)流逐(zhu)漸減小,當(dang)電(dian)(dian)池(chi)(chi)充(chong)(chong)足電(dian)(dian)后,進人(ren)涓流充(chong)(chong)電(dian)(dian)過(guo)程。為(wei)避免過(guo)充(chong)(chong)電(dian)(dian)或過(guo)放電(dian)(dian),鋰(li)離(li)子(zi)電(dian)(dian)池(chi)(chi)不僅在內(nei)部設有安全(quan)機構,充(chong)(chong)電(dian)(dian)器(qi)也(ye)必須采取安全(quan)保護措施(shi),以監測鋰(li)離(li)子(zi)電(dian)(dian)池(chi)(chi)的充(chong)(chong)放電(dian)(dian)狀態(tai)。

    2.二(er)次電(dian)池性能(neng)比較

1l為鉛酸、鎳銅、鎳氫、鋰(li)離子電池特性的(de)比較。

 

    20世紀80年代(dai)的便攜式電子設備,如數字無繩電話、隨身(shen)聽和電動剃須(xu)刀(dao)等,主要由鎳鎘電池供電。到了20世紀(ji)90年代后期,鎳(nie)氫電(dian)(dian)池(chi)和(he)鋰離子(zi)電(dian)(dian)池(chi)逐漸進入市場(chang)并得以廣泛(fan)應用(yong)。因為(wei)鎳(nie)鎘電(dian)(dian)池(chi)的(de)價格比鎳(nie)氫和(he)鋰離子(zi)電(dian)(dian)池(chi)便宜,所以鎳(nie)鎘電(dian)(dian)池(chi)在低端應用(yong)中十分(fen)普(pu)遍。鎳(nie)鎘電(dian)(dian)池(chi)可(ke)提供(gong)最(zui)高的(de)放(fang)電(dian)(dian)電(dian)(dian)流,適合短時間內(nei)需(xu)要大(da)功率(lv)輸出的(de)應用(yong)。

    鎳(nie)鎘電池的(de)(de)缺點是被所謂的(de)(de)記憶(yi)效應困擾(現在的(de)(de)鎳(nie)鎘電池很少考慮這個因素), 使電(dian)池(chi)(chi)容量降低。鎳鎘電(dian)池(chi)(chi)在未(wei)完(wan)全放電(dian)的情況下再充電(dian),一些活(huo)性(xing)物質會累積并(bing)且開始結晶(在陽極有(you)100μm的銅累積層), 但通過化學反應這層(ceng)物(wu)質會自行(xing)消失(shi)(一塊全新電(dian)池(chi)的陽極大約有l00μm厚度的鎘結晶), 出現記憶效應會導(dao)致電池容量越來(lai)越小,端電壓越來(lai)越低,使得(de)電池到達(da)最低可用(yong)端電壓(關斷(duan)點)的時(shi)間(jian)比預期(qi)的早很(hen)多,如圖1-1所示。鎳鎘(ge)電池的(de)另(ling)一個缺點是它的(de)活性物(wu)質(zhi)中含(han)有有毒的(de)鎘(ge)。

    鎳氫電池比鎳鎘電池環保,但是價格高。鎳氫電池的放電電流相比鎳鎘電池略小,但也受惰性效應的影響。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

    鋰離子(zi)(zi)可充電電池價(jia)格最高,但具有高的(de)能(neng)量(liang)密(mi)度,因而可以在給定尺寸下提供(gong)更優性能(neng),更適合(he)小(xiao)尺寸、高集成度的(de)便(bian)攜(xie)式(shi)電子(zi)(zi)設備。

    隨著新材料、新工藝的(de)(de)出現,更(geng)(geng)為(wei)先(xian)進耐用(yong)的(de)(de)可再充電電池(chi)(chi)也在不斷(duan)出現。國(guo)外最(zui)新開(kai)發(fa)的(de)(de)固(gu)態聚(ju)合物(電解質(zhi))鋰(li)離(li)子電池(chi)(chi)、鋰(li)金屬(shu)電池(chi)(chi)不僅解決了漏液問題,而且(qie)電池(chi)(chi)的(de)(de)容量更(geng)(geng)大,體積(ji)更(geng)(geng)小(xiao),更(geng)(geng)為(wei)安全可靠,它們必將(jiang)成為(wei)極有潛力的(de)(de)新一代電池(chi)(chi)產(chan)品。

    3.鎳氫/鎳鎘電池與(yu)鋰離子電池的差異

    1)質(zhi)量方面。以每(mei)一個單元電池的電壓來看,鎳氫(qing)與鎳鎘(ge)都是12V,而鋰離子(zi)電池卻為36V,鋰離子電池的(de)(de)電壓是前(qian)兩者(zhe)的(de)(de)3倍。并且同型電(dian)池的質(zhi)量鋰離子電(dian)池與鎳鎘電(dian)池幾(ji)乎相等,而鎳氫電(dian)池卻(que)比較重(zhong)。每(mei)一(yi)種(zhong)電(dian)池本身(shen)質(zhi)量不同,但(dan)鋰離子電(dian)池因36V高電壓,在輸(shu)出同等電壓的情況下使(shi)單個電池組合(he)時數目可減少 1/3而使(shi)成型后的電池質量和體積減小。

    2)記憶效(xiao)應(ying)。鎳(nie)氫電(dian)池有(you)惰性效(xiao)應(ying);鎳(nie)鎘電(dian)池有(you)記憶效(xiao)應(ying),因(yin)此,定期的放(fang)(fang)(fang)電(dian)管理也是必需的。這種定期放(fang)(fang)(fang)電(dian)管理屬于(yu)模糊狀(zhuang)態(tai)下被動處理,甚至(zhi)也有(you)些在不正(zheng)確的情況下進行放(fang)(fang)(fang)電(dian)(每次放(fang)(fang)(fang)電(dian)或者使用幾次后(hou)進行放(fang)(fang)(fang)電(dian)都因(yin)電(dian)池生產廠的不同(tong)而有(you)所差異(yi)), 這種繁瑣(suo)的放電管理在(zai)使用鎳鎘/鎳氫電池時是無法避免的。相對的鋰離子電池因為完全沒有記憶效應,在使用上非常方便簡單,它完全不必考慮二次電池殘余電壓的多少,直接可進行充電,充電時間自然可以縮短。

    記憶效(xiao)應(ying)是充(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)池的(de)一(yi)大(da)天(tian)敵,一(yi)般(ban)認為是長(chang)期不(bu)正(zheng)確的(de)充(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)導致的(de),它可(ke)以使(shi)電(dian)(dian)(dian)(dian)(dian)池早(zao)衰。記憶效(xiao)應(ying)可(ke)使(shi)電(dian)(dian)(dian)(dian)(dian)池無(wu)法有(you)效(xiao)地充(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian),出(chu)現(xian)一(yi)充(chong)(chong)(chong)(chong)就滿、一(yi)用就完的(de)現(xian)象(xiang)。防(fang)止(zhi)電(dian)(dian)(dian)(dian)(dian)池出(chu)現(xian)記憶效(xiao)應(ying)的(de)方法是確保電(dian)(dian)(dian)(dian)(dian)池“充(chong)(chong)(chong)(chong)足放(fang)光”的(de)原則,也就是說在充(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)前最好將(jiang)電(dian)(dian)(dian)(dian)(dian)池內(nei)殘(can)余電(dian)(dian)(dian)(dian)(dian)量放(fang)光,充(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)時(shi)要一(yi)次(ci)(ci)充(chong)(chong)(chong)(chong)足。通(tong)常鎳(nie)鎘電(dian)(dian)(dian)(dian)(dian)池容易出(chu)現(xian)記憶效(xiao)應(ying),所以充(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)時(shi)要特(te)別(bie)注意(yi),鎳(nie)氫(qing)電(dian)(dian)(dian)(dian)(dian)池理論上沒有(you)記憶效(xiao)應(ying),但最好也遵循“充(chong)(chong)(chong)(chong)足放(fang)光”的(de)原則,這也就是很多充(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)器提供(gong)放(fang)電(dian)(dian)(dian)(dian)(dian)附加(jia)功(gong)能的(de)原因。對于(yu)由(you)于(yu)記憶效(xiao)應(ying)引起容量下降的(de)電(dian)(dian)(dian)(dian)(dian)池,可(ke)以通(tong)過一(yi)次(ci)(ci)性充(chong)(chong)(chong)(chong)足再一(yi)次(ci)(ci)性放(fang)光的(de)方法反復數次(ci)(ci),大(da)部分電(dian)(dian)(dian)(dian)(dian)池都可(ke)以得到修復。

    3)自放(fang)電率。鎳鎘(ge)電池的自放(fang)電率為15%~30%(月), 鎳(nie)氫電(dian)池(chi)的自放電(dian)率為25%~35%(月),鋰離子電(dian)池的自放電(dian)率為2%~5%(月),鎳(nie)氫電池的自(zi)放電率最(zui)大,而鋰離子電池的自(zi)放電率最(zui)低。

    4)充(chong)(chong)電(dian)(dian)(dian)(dian)方(fang)(fang)式(shi)。充(chong)(chong)電(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)池的充(chong)(chong)電(dian)(dian)(dian)(dian)方(fang)(fang)式(shi)一直是人們關心的焦點(dian),正確(que)(que)、良好(hao)的充(chong)(chong)電(dian)(dian)(dian)(dian)方(fang)(fang)法(fa)可以(yi)確(que)(que)保(bao)電(dian)(dian)(dian)(dian)池的壽命(ming)。充(chong)(chong)電(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)池推薦的充(chong)(chong)電(dian)(dian)(dian)(dian)方(fang)(fang)法(fa)多(duo)(duo)種多(duo)(duo)樣,不(bu)(bu)同的充(chong)(chong)電(dian)(dian)(dian)(dian)方(fang)(fang)法(fa)對(dui)充(chong)(chong)電(dian)(dian)(dian)(dian)器的電(dian)(dian)(dian)(dian)路結構(gou)有不(bu)(bu)同的要求,自(zi)然影響到成本。

    電(dian)(dian)(dian)(dian)池(chi)充電(dian)(dian)(dian)(dian)時間(jian)和充電(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)流的關系為電(dian)(dian)(dian)(dian)池(chi)容量除以充電(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)流得到(dao)充電(dian)(dian)(dian)(dian)時間(jian),考慮充電(dian)(dian)(dian)(dian)過程中的損耗,所以將計(ji)算得到(dao)的充電(dian)(dian)(dian)(dian)時間(jian)應再乘以12這個常數。

    對于鎳鎘和鎳氫電(dian)池最常用的簡單充電(dian)方法是利用10C恒流(liu)充電(dian),又被(bei)稱為“慢充”,即按(an)照電(dian)流(liu)容量數值的(de)10%確定充電(dian)(dian)電(dian)(dian)流,如一節標稱容量為500mAh的電(dian)(dian)池,它(ta)的建議充(chong)電(dian)(dian)電(dian)(dian)流為50mA;又如一節標稱容量(liang)為(wei)1300mAh的電池(chi),它的建議充電電流為13 0 mA。在此電(dian)流(liu)下連續充電(dian)1215  h就可以視為(wei)電(dian)池(chi)充滿。雖然建議使用恒流充電(dian)但要(yao)求并不嚴格(ge),電(dian)流允許有較大的波(bo)動,所以按照此方(fang)法制作的充電(dian)器結構非常簡單,一(yi)(yi)般只需要(yao)一(yi)(yi)個將220V市(shi)電(dian)(dian)(dian)轉換(huan)成(cheng)(cheng)適當(dang)低壓的變(bian)壓器、整(zheng)流(liu)的二極(ji)管、限流(liu)電(dian)(dian)(dian)阻以及(ji)一(yi)些發(fa)光二極(ji)管等指示裝置(zhi)構(gou)成(cheng)(cheng)低成(cheng)(cheng)本(ben)的充(chong)電(dian)(dian)(dian)器,市(shi)面上絕大部分獨立常規充(chong)電(dian)(dian)(dian)器都采(cai)用(yong)這種方式(shi),只不過(guo)外形不同罷了(le)。“慢充(chong)”雖(sui)然比較簡單(dan),但是給電(dian)(dian)(dian)池充(chong)一(yi)次電(dian)(dian)(dian)需要十多(duo)個小時,為此(ci),電(dian)(dian)(dian)池廠商也允許在急需使用(yong)時用(yong) 3 0C的電(dian)(dian)流給電(dian)(dian)池(chi)充電(dian)(dian) 45 h,稱之為“快(kuai)充”,不過不建議常用,理(li)論上對電池(chi)有輕微的損害。所(suo)以大部分常規充(chong)電器都有“快充(chong)”和“慢(man)充(chong)”兩擋,并建議用戶使用“慢(man)充(chong)”。

    在很多情況下用(yong)戶需要(yao)對(dui)電(dian)(dian)池快速(su)、有效(xiao)、安(an)全地充(chong)(chong)(chong)電(dian)(dian),快速(su)充(chong)(chong)(chong)電(dian)(dian)就需要(yao)使(shi)(shi)用(yong)較(jiao)大的電(dian)(dian)流。電(dian)(dian)池在大電(dian)(dian)流充(chong)(chong)(chong)電(dian)(dian)過程中會出現極化效(xiao)應,使(shi)(shi)電(dian)(dian)池發(fa)熱(re),而且當大電(dian)(dian)流充(chong)(chong)(chong)電(dian)(dian)電(dian)(dian)池充(chong)(chong)(chong)滿后,如果不(bu)及時停止,電(dian)(dian)池會迅速(su)發(fa)熱(re),嚴重時可(ke)導致(zhi)電(dian)(dian)池燒毀和爆炸。所以要(yao)求(qiu)快速(su)充(chong)(chong)(chong)電(dian)(dian)器(qi)(qi)具備充(chong)(chong)(chong)滿自停功能,同時也要(yao)解(jie)決極化效(xiao)應,使(shi)(shi)充(chong)(chong)(chong)電(dian)(dian)高效(xiao)安(an)全。早期的快速(su)充(chong)(chong)(chong)電(dian)(dian)器(qi)(qi)采用(yong)簡單的定(ding)時充(chong)(chong)(chong)電(dian)(dian),不(bu)過此類(lei)充(chong)(chong)(chong)電(dian)(dian)器(qi)(qi)針對(dui)性強(qiang),充(chong)(chong)(chong)電(dian)(dian)效(xiao)果也不(bu)令人滿意。現代的充(chong)(chong)(chong)電(dian)(dian)器(qi)(qi)采用(yong)專用(yong)的充(chong)(chong)(chong)電(dian)(dian)控(kong)制IC,以高(gao)頻(pin)脈(mo)動(dong)電(dian)(dian)(dian)流給電(dian)(dian)(dian)池充電(dian)(dian)(dian)以解決極化(hua)效應(ying),通過(guo)檢測(ce)電(dian)(dian)(dian)池一出準確判斷電(dian)(dian)(dian)池是否(fou)充滿,并(bing)提供溫度保(bao)護(hu)等(deng)保(bao)護(hu)措(cuo)施(shi)和放電(dian)(dian)(dian)等(deng)附加功(gong)能。不過(guo)這種(zhong)充電(dian)(dian)(dian)器結構比較(jiao)復雜,成(cheng)本也(ye)比較(jiao)高(gao),一般多用于移動(dong)電(dian)(dian)(dian)話、對(dui)講機等(deng)高(gao)檔(dang)通信設(she)備(bei)及(ji)電(dian)(dian)(dian)器。

    6.各種電池的(de)優缺點

    鎳鎘電(dian)(dian)池(chi)最(zui)為(wei)堅固(gu)耐用,每塊鎳鋼電(dian)(dian)池(chi)的(de)電(dian)(dian)壓為(wei)12V,多數應(ying)用需要多個(ge)電(dian)池串聯(lian)或并聯(lian)才能滿足要求(qiu)。鎳鎘(ge)電(dian)池應(ying)用中的最(zui)大(da)問題(ti)是它(ta)具有記憶效應(ying),這一點嚴重(zhong)限制了(le)它(ta)在高端設備中的應(ying)用。

    考慮到回收(shou)和環保問題(ti),鎳(nie)鎘(ge)電(dian)(dian)池(chi)在其他產品中的(de)應用也較(jiao)(jiao)少。與其他電(dian)(dian)池(chi)相(xiang)比(bi),鎳(nie)鎘(ge)電(dian)(dian)池(chi)的(de)耗電(dian)(dian)率(lv)、使(shi)用壽(shou)命都令人非常滿意,而且(qie)在極差(cha)的(de)溫(wen)度條(tiao)件下也能(neng)保持(chi)良好的(de)性能(neng)。但(dan)是,盡管鎳(nie)鎘(ge)電(dian)(dian)池(chi)比(bi)較(jiao)(jiao)經濟,但(dan)它的(de)電(dian)(dian)量也較(jiao)(jiao)低(di),相(xiang)同(tong)的(de)鎳(nie)鎘(ge)電(dian)(dian)池(chi)工作時間(jian)大約只(zhi)有鎳(nie)氫電(dian)(dian)池(chi)的(de)一半,因此多(duo)數(shu)鎳(nie)鎘(ge)電(dian)(dian)池(chi)都沉重(zhong)且(qie)體(ti)(ti)積(ji)龐大。

    鎳氫電(dian)(dian)池沒(mei)有鎳鎘(ge)電(dian)(dian)池那么堅固耐用,在(zai)能量密度(du)上也無法與鋰離子(zi)電(dian)(dian)池競爭,但與鎳鎘(ge)電(dian)(dian)池相比它(ta)具有更佳的(de)性價比。鎳氫電(dian)(dian)池的(de)電(dian)(dian)壓與鎳鎘(ge)電(dian)(dian)池的(de)相同,每(mei)塊電(dian)(dian)池為12V。由于(yu)主(zhu)要的(de)電(dian)池應用市場如筆記本電(dian)腦及移(yi)動(dong)電(dian)話開始轉(zhuan)為使(shi)用鋰(li)離子電(dian)池,鎳氫(qing)電(dian)池的(de)研發有所放緩,從理論上說,現有鎳氫(qing)電(dian)池的(de)電(dian)量也快(kuai)接近其(qi)極限(xian)。因此,目前的(de)研發主(zhu)要是(shi)增強其(qi)耐用性,以便適用于(yu)電(dian)動(dong)工具和(he)混(hun)合電(dian)動(dong)汽(qi)車等其(qi)他市場。

    從鋰離(li)(li)子電(dian)(dian)池開始進入市(shi)場至(zhi)今已十幾年,由于日益成熟,鋰離(li)(li)子電(dian)(dian)池也變得更為堅固耐用,價格也有(you)所下降(jiang)。單個鋰離(li)(li)子電(dian)(dian)池的電(dian)(dian)壓(ya)力37V,與三節(jie)鎳(nie)鎘電(dian)池(chi)(chi)或鎳(nie)氫(qing)電(dian)池(chi)(chi)一樣。能(neng)量密度高和自(zi)放電(dian)低(di)是鋰(li)離(li)子電(dian)池(chi)(chi)在(zai)市場上成功的(de)法寶,目前(qian)這種電(dian)池(chi)(chi)還(huan)開發增(zeng)加了(le)許多(duo)新(xin)的(de)性能(neng)。例(li)如,鋰(li)離(li)子電(dian)池(chi)(chi)廠商正在(zai)開發無需保護(hu)電(dian)路的(de)產品,以便進一步降低(di)其(qi)成本。

        121 鎳(nie)鎘電池的結構與特性

1899年,Waldmar Jungner在開口(kou)型(xing)鎳(nie)鎘電(dian)池中首先使用(yong)了鎳(nie)極板,幾乎與此同(tong)時,Thomas Edison發明(ming)了用(yong)于電(dian)動車的(de)(de)鎳鎘(ge)電(dian)池(chi)。但因(yin)當(dang)時這些堿性(xing)蓄(xu)電(dian)池(chi)的(de)(de)極板材料比其他蓄(xu)電(dian)池(chi)的(de)(de)村料貴得多(duo),因(yin)此(ci)實際應用(yong)受(shou)到了極大的(de)(de)限制。Jungner的鎳鎘(ge)電池經過幾次重要(yao)改進,性能明顯改善。其中最重要(yao)的改進是在(zai)1932年,在鎳電(dian)池(chi)中開始(shi)使(shi)用了活(huo)性物質(zhi)。將活(huo)性物質(zhi)放人多孔的(de)鎳極板(ban)中,然后再將鎳極板(ban)裝人金屬殼內。鎳鎘電(dian)池(chi)發展史(shi)上另一個重要的(de)里程(cheng)碑(bei)是(shi)1947年密(mi)封型(xing)鎳鎘電池(chi)(chi)研制成(cheng)功(gong)。在(zai)這種(zhong)電池(chi)(chi)中,化學反應產生的(de)各種(zhong)氣(qi)體(ti)不用(yong)排(pai)出(chu),可以在(zai)電池(chi)(chi)內部化合(he)。密(mi)封鎳鋼電池(chi)(chi)的(de)研制成(cheng)功(gong),使鎳鋼電池(chi)(chi)的(de)應用(yong)范圍大大增加.

    1.鎳鎘電池(chi)的特性

鎳鎘(NiCd)電(dian)(dian)池(chi)要求(qiu)恒流充電(dian)(dian),充電(dian)(dian)器(qi)對電(dian)(dian)池(chi)進行恒流充電(dian)(dian)的同時檢測電(dian)(dian)池(chi)的電(dian)(dian)壓和其(qi)他參數。當電(dian)(dian)池(chi)電(dian)(dian)壓第一(yi)次下降(jiang)了一(yi)個-ΔU時終止快速充(chong)電(dian)。為(wei)避免損壞(huai)電(dian)池(chi),電(dian)池(chi)溫度過低(di)時不能開始快速充(chong)電(dian),電(dian)池(chi)溫度 Tmin低于 100C時,應轉入涓(juan)流充電(dian)方(fang)式(shi)。而電(dian)池溫度(du)一旦達到(dao)規定數值后,必須立即停止充電(dian)。密(mi)封鎳(nie)鎘電(dian)池效率高、循環壽命長、能量密(mi)度(du)大、體(ti)積小、質量輕、結構緊湊(cou),并且不需要維護,因此在(zai)工業(ye)和消費產品中得到(dao)了(le)廣泛的應用。

(1)鎳鋼電(dian)池的基本特性。

 l)鎳鎘電池可重復(fu)500次以上(shang)的充(chong)放電(dian),非常經濟。

2)鎳鎘電池(chi)內(nei)阻小(xiao),可供大(da)電流的(de)(de)放電,放電時電壓(ya)的(de)(de)變化很小(xiao),作為直流電源是(shi)一種質量極佳(jia)的(de)(de)電池(chi)。

 3)因為鎳鎘電池采用完全密(mi)封式,因此不(bu)(bu)會有電解(jie)液(ye)漏出(chu)的現(xian)象(xiang),也完全不(bu)(bu)需要補充電解(jie)液(ye)。

 4)與其他種類電池(chi)相比,鎳鎘電池(chi)可耐過(guo)充(chong)電或(huo)過(guo)放電,操作簡單方便。

5)鎳鎘(ge)電池在長時間(jian)的(de)放置下也(ye)不會使性能劣(lie)化,當充分充完(wan)電后(hou)即(ji)可恢復(fu)原來(lai)的(de)特性。

6)鎳鎘(ge)電池可使用在(zai)很廣(guang)的(de)溫(wen)度(du)范圍內。

7)因(yin)(yin)為鎳(nie)鎘(ge)電池采用金屬(shu)容器,因(yin)(yin)此具有機(ji)械的(de)堅固(gu)性。

    (2)鎳鎘(ge)電(dian)池放電(dian)特性。

    l)鎳鎘電(dian)池放電(dian)電(dian)壓依據其放電(dian)電(dian)流多少有些差異,大體(ti)上(shang)是(shi)12V左右。

    2)當(dang)放(fang)電(dian)(dian)(dian)達到放(fang)電(dian)(dian)(dian)終了的極限電(dian)(dian)(dian)壓(ya)(ya)稱之(zhi)為(wei)“放(fang)電(dian)(dian)(dian)終止電(dian)(dian)(dian)壓(ya)(ya)”,鎳鎘(ge)電(dian)(dian)(dian)池的放(fang)電(dian)(dian)(dian)終止電(dian)(dian)(dian)壓(ya)(ya)為(wei)10 V/單格。

    3)鎳鎘電池使(shi)用溫(wen)度(du)范(fan)圍為一20600C,在此(ci)范圍內可進行放電。

    4)鎳鎘電(dian)池可(ke)為(wei)一30500C的溫度范圍(wei)之間保存(cun),但如果是長時(shi)間放置的情形下,應(ying)在(zai) 350C以(yi)下保存。

    5)鎳鎘電(dian)池在(zai)充電(dian)狀(zhuang)態或者是放(fang)電(dian)狀(zhuang)態保存都(dou)可(ke)以(yi),但是比較之下(xia)放(fang)電(dian)狀(zhuang)態可(ke)使(shi)容(rong)量較早恢復并(bing)且較易被激活。

6)當(dang)鎳鎘電(dian)池在長時間放置后(hou),使用(yong)前必須充(chong)分地充(chong)電(dian)后(hou)再使用(yong)。

 2.鎳鎘(ge)電池參數

鎳(nie)鎘電池的5個主要參數為:電池的容量、標稱電壓、內阻、放電終止電壓和充電終止電壓。電池的容量通常用Ah(安時(shi))表示,1Ah就(jiu)是能在1A的電流下放電1h。單(dan)元電(dian)池(chi)(chi)內(nei)活性物質的(de)(de)數量決定單(dan)元電(dian)池(chi)(chi)含有的(de)(de)電(dian)荷量,而(er)活性物質的(de)(de)含量則由電(dian)池(chi)(chi)使用的(de)(de)材料和體(ti)(ti)積決定,因(yin)此,通(tong)常電(dian)池(chi)(chi)體(ti)(ti)積越大,容(rong)量越高。與電(dian)池(chi)(chi)容(rong)量相關的(de)(de)一個(ge)參數是電(dian)池(chi)(chi)的(de)(de)充(chong)電(dian)電(dian)流。電(dian)池(chi)(chi)的(de)(de)充(chong)電(dian)電(dian)流通(tong)常用充(chong)電(dian)速(su)率C表示,C為電池的(de)額定(ding)容(rong)量。例如,用2A電流對1Ah電池充電,充電速(su)率就是(shi)2C;同樣(yang)地,用2A電流對(dui)500mAh電(dian)(dian)池充電(dian)(dian),充電(dian)(dian)速率就(jiu)是 4C

電(dian)(dian)(dian)池(chi)(chi)剛出廠時(shi),正(zheng)負極之間的(de)電(dian)(dian)(dian)勢差稱(cheng)為電(dian)(dian)(dian)池(chi)(chi)的(de)標(biao)稱(cheng)電(dian)(dian)(dian)壓(ya)。標(biao)稱(cheng)電(dian)(dian)(dian)壓(ya)由極板材(cai)料的(de)電(dian)(dian)(dian)極電(dian)(dian)(dian)位和內部電(dian)(dian)(dian)解液的(de)濃度決定。當環境(jing)溫度、使用時(shi)間和工作狀態(tai)變(bian)化時(shi),單元電(dian)(dian)(dian)池(chi)(chi)的(de)輸出電(dian)(dian)(dian)壓(ya)略有變(bian)化,此外,電(dian)(dian)(dian)池(chi)(chi)的(de)輸出電(dian)(dian)(dian)壓(ya)與(yu)電(dian)(dian)(dian)池(chi)(chi)的(de)剩余電(dian)(dian)(dian)量也(ye)有一定的(de)關(guan)系。單元鎳(nie)鎘電(dian)(dian)(dian)池(chi)(chi)的(de)標(biao)稱(cheng)電(dian)(dian)(dian)壓(ya)約為12V(但一般認(ren)為是(shi)125V.

電池(chi)的(de)(de)內阻決定于極(ji)板的(de)(de)電阻和離(li)子(zi)(zi)流(liu)的(de)(de)阻抗,在(zai)充放電過程中,極(ji)板的(de)(de)電阻是不(bu)變的(de)(de),但是離(li)子(zi)(zi)流(liu)的(de)(de)阻抗將隨(sui)電解液濃度的(de)(de)變化和帶(dai)電離(li)子(zi)(zi)的(de)(de)增減而變化。

電(dian)池(chi)充足電(dian)時(shi),極板上的活性物質已達到飽和狀態,再繼續(xu)充電(dian), ,電(dian)池(chi)的電(dian)壓(ya)(ya)(ya)也不會上升,此時(shi)的電(dian)壓(ya)(ya)(ya)稱(cheng)為(wei)充電(dian)終止電(dian)壓(ya)(ya)(ya)。鎳鎘電(dian)池(chi)的充電(dian)終止電(dian)壓(ya)(ya)(ya)為(wei)17 518V

放(fang)電(dian)(dian)終(zhong)止電(dian)(dian)壓(ya)(ya)是指電(dian)(dian)池(chi)(chi)放(fang)電(dian)(dian)時(shi)允(yun)許的(de)(de)最低(di)電(dian)(dian)壓(ya)(ya)。如(ru)果電(dian)(dian)壓(ya)(ya)低(di)于(yu)放(fang)電(dian)(dian)終(zhong)止電(dian)(dian)壓(ya)(ya)后電(dian)(dian)池(chi)(chi)繼(ji)續放(fang)電(dian)(dian),電(dian)(dian)池(chi)(chi)兩(liang)端電(dian)(dian)壓(ya)(ya)會迅(xun)速下降,形(xing)成(cheng)(cheng)深度(du)放(fang)電(dian)(dian),這(zhe)樣極(ji)板(ban)上形(xing)成(cheng)(cheng)的(de)(de)生成(cheng)(cheng)物在正常(chang)充電(dian)(dian)時(shi)就不易再(zai)恢復,從而影響電(dian)(dian)池(chi)(chi)的(de)(de)壽命。放(fang)電(dian)(dian)終(zhong)止電(dian)(dian)壓(ya)(ya)和放(fang)電(dian)(dian)率有關。鎳鎘電(dian)(dian)池(chi)(chi)的(de)(de)放(fang)電(dian)(dian)終(zhong)止電(dian)(dian)壓(ya)(ya)和放(fang)電(dian)(dian)速率的(de)(de)

返回
頂部
lutube-lutube下载-lutube下载地址-lutube最新地址 lutube-lutube下载-lutube下载地址-lutube最新地址 lutube-lutube下载-lutube下载地址-lutube最新地址