綠色革命可(ke)(ke)能(neng)(neng)不(bu)久就將迎來一場重(zhong)大勝利(li)。在(zai)大規(gui)模的(de)(de)電(dian)(dian)(dian)能(neng)(neng)成(cheng)為“可(ke)(ke)儲存(cun)”和(he)(he)“便攜式”能(neng)(neng)源之時(shi)，能(neng)(neng)量(liang)效(xiao)率將獲得(de)顯(xian)著改善，而且可(ke)(ke)再生(sheng)(sheng)能(neng)(neng)源的(de)(de)推動工作也將取得(de)進(jin)展(zhan)。可(ke)(ke)儲存(cun)性和(he)(he)便攜性是(shi)液(ye)體燃(ran)料(liao)的(de)(de)主要優(you)(you)勢(shi)，而通過電(dian)(dian)(dian)池系統(tong)提供的(de)(de)電(dian)(dian)(dian)力(li)則擁有(you)(you)提供一種可(ke)(ke)行(xing)替代方案(an)(an)的(de)(de)潛力(li)。電(dian)(dian)(dian)能(neng)(neng)可(ke)(ke)在(zai)幾乎(hu)所有(you)(you)的(de)(de)耗能(neng)(neng)設備中(zhong)使(shi)用，而且，電(dian)(dian)(dian)能(neng)(neng)也可(ke)(ke)以從幾乎(hu)所有(you)(you)的(de)(de)可(ke)(ke)用能(neng)(neng)源來產生(sheng)(sheng)。核能(neng)(neng)、太陽(yang)能(neng)(neng)、風(feng)能(neng)(neng)、地熱能(neng)(neng)和(he)(he)液(ye)體燃(ran)料(liao)(汽油、柴油、乙醇(chun)、氫等(deng)等(deng))都能(neng)(neng)很容(rong)易地轉換成(cheng)電(dian)(dian)(dian)能(neng)(neng)。因此，與(yu)石油燃(ran)料(liao)相比，電(dian)(dian)(dian)力(li)的(de)(de)重(zhong)大優(you)(you)勢(shi)是(shi)可(ke)(ke)以利(li)用最具成(cheng)本效(xiao)益的(de)(de)解決方案(an)(an)隨時(shi)隨地產生(sheng)(sheng)能(neng)(neng)量(liang)。

       對電(dian)(dian)(dian)能(neng)(neng)的(de)(de)規(gui)范化可(ke)(ke)以同(tong)時(shi)實現規(gui)模經濟，并免除局部燃料消耗所需(xu)的(de)(de)基礎設(she)施。優(you)越的(de)(de)電(dian)(dian)(dian)能(neng)(neng)可(ke)(ke)儲(chu)存(cun)性便于發(fa)電(dian)(dian)(dian)(效率最高，且(qie)不是“按需(xu)”型的(de)(de))，目前的(de)(de)情況大體(ti)如此。例如：風(feng)力發(fa)電(dian)(dian)(dian)和太陽能(neng)(neng)發(fa)電(dian)(dian)(dian)未必與(yu)峰值功率需(xu)求模式相吻合，而可(ke)(ke)儲(chu)存(cun)特性則(ze)能(neng)(neng)緩(huan)解這個問題有所緩(huan)解。優(you)越的(de)(de)便攜性允(yun)許電(dian)(dian)(dian)能(neng)(neng)作(zuo)為汽車(耗能(neng)(neng)大戶(hu))的(de)(de)能(neng)(neng)源(yuan)。隨著時(shi)間的(de)(de)推移(yi)，其他傾向于使用(yong)綠色能(neng)(neng)源(yuan)的(de)(de)應(ying)用(yong)肯定(ding)將(jiang)得益于此項(xiang)技(ji)術。

電動(dong)汽車對電池系統的(de)要求(qiu)

       電(dian)(dian)(dian)動(dong)(dong)(dong)(dong)汽(qi)(qi)車(che)(che)(che)(che)為(wei)(wei)(wei)綠色革命提供了一(yi)(yi)(yi)個巨大的(de)(de)(de)(de)(de)發展機遇，原(yuan)因有(you)很(hen)多。電(dian)(dian)(dian)動(dong)(dong)(dong)(dong)汽(qi)(qi)車(che)(che)(che)(che)采用(yong)電(dian)(dian)(dian)網電(dian)(dian)(dian)力取代了燃(ran)(ran)(ran)氣動(dong)(dong)(dong)(dong)力。電(dian)(dian)(dian)網電(dian)(dian)(dian)力的(de)(de)(de)(de)(de)生成效(xiao)(xiao)(xiao)(xiao)率(lv)(lv)(lv)很(hen)高，可以(yi)從幾乎(hu)所有(you)的(de)(de)(de)(de)(de)能(neng)(neng)源(yuan)來獲得。此外(wai)，電(dian)(dian)(dian)動(dong)(dong)(dong)(dong)汽(qi)(qi)車(che)(che)(che)(che)的(de)(de)(de)(de)(de)能(neng)(neng)源(yuan)使用(yong)效(xiao)(xiao)(xiao)(xiao)率(lv)(lv)(lv)也高于(yu)燃(ran)(ran)(ran)油(you)汽(qi)(qi)車(che)(che)(che)(che)。大多數汽(qi)(qi)車(che)(che)(che)(che)在(zai)運行時(shi)將經歷一(yi)(yi)(yi)個“加速(su)、減(jian)速(su)和空轉”的(de)(de)(de)(de)(de)連續周期。相(xiang)比之下，易(yi)變的(de)(de)(de)(de)(de)負載(比如加速(su)或減(jian)速(su))更有(you)利(li)于(yu)電(dian)(dian)(dian)動(dong)(dong)(dong)(dong)馬達(da)(而非燃(ran)(ran)(ran)油(you)引(yin)擎(qing)(qing))，因為(wei)(wei)(wei)它在(zai)低(di)速(su)條件(jian)下提供了高轉矩(ju)。燃(ran)(ran)(ran)油(you)引(yin)擎(qing)(qing)的(de)(de)(de)(de)(de)工作(zuo)效(xiao)(xiao)(xiao)(xiao)率(lv)(lv)(lv)只在(zai)一(yi)(yi)(yi)個很(hen)窄(zhai)的(de)(de)(de)(de)(de)速(su)度/負載范圍(wei)內達(da)到最高，而且為(wei)(wei)(wei)滿足峰值加速(su)的(de)(de)(de)(de)(de)需要(yao)，它必須是超大型的(de)(de)(de)(de)(de)。用(yong)于(yu)把汽(qi)(qi)油(you)能(neng)(neng)量(liang)轉換(huan)(huan)為(wei)(wei)(wei)動(dong)(dong)(dong)(dong)能(neng)(neng)的(de)(de)(de)(de)(de)引(yin)擎(qing)(qing)效(xiao)(xiao)(xiao)(xiao)率(lv)(lv)(lv)通常為(wei)(wei)(wei) 20%，而電(dian)(dian)(dian)動(dong)(dong)(dong)(dong)馬達(da)將電(dian)(dian)(dian)能(neng)(neng)轉換(huan)(huan)為(wei)(wei)(wei)動(dong)(dong)(dong)(dong)能(neng)(neng)的(de)(de)(de)(de)(de)過程中(zhong)可以(yi)實現 90% 的(de)(de)(de)(de)(de)典型效(xiao)(xiao)(xiao)(xiao)率(lv)(lv)(lv)。此外(wai)，電(dian)(dian)(dian)動(dong)(dong)(dong)(dong)馬達(da)還(huan)無(wu)須在(zai)停靠時(shi)因為(wei)(wei)(wei)空轉而無(wu)謂地消耗能(neng)(neng)量(liang)，而且電(dian)(dian)(dian)動(dong)(dong)(dong)(dong)系(xi)統還(huan)具備通過再生制動(dong)(dong)(dong)(dong)來恢復機械能(neng)(neng)的(de)(de)(de)(de)(de)潛(qian)力。通過電(dian)(dian)(dian)動(dong)(dong)(dong)(dong)汽(qi)(qi)車(che)(che)(che)(che)的(de)(de)(de)(de)(de)典型能(neng)(neng)耗成本僅為(wei)(wei)(wei)0.013美元/英里這一(yi)(yi)(yi)事(shi)實，便能(neng)(neng)看出能(neng)(neng)量(liang)效(xiao)(xiao)(xiao)(xiao)率(lv)(lv)(lv)的(de)(de)(de)(de)(de)整體改善(shan)情況。

遺憾(han)的(de)(de)(de)是，在(zai)現今的(de)(de)(de)市場上，純(chun)電(dian)(dian)(dian)動(dong)(dong)(dong)汽(qi)車(che)還(huan)不是一(yi)種可行(xing)的(de)(de)(de)解決方案，因為其行(xing)駛(shi)距(ju)(ju)離受限于(yu)車(che)上所能(neng)儲存的(de)(de)(de)能(neng)量。如(ru)今常見的(de)(de)(de)電(dian)(dian)(dian)池(chi)組在(zai)充電(dian)(dian)(dian)8小時(shi)之后能(neng)夠讓(rang)一(yi)輛(liang)(liang)電(dian)(dian)(dian)動(dong)(dong)(dong)汽(qi)車(che)行(xing)駛(shi)100英里(li)。而(er)一(yi)個普通(tong)的(de)(de)(de)汽(qi)車(che)油箱則能(neng)為一(yi)輛(liang)(liang)標準(zhun)汽(qi)車(che)提供300英里(li)的(de)(de)(de)行(xing)駛(shi)距(ju)(ju)離，且只(zhi)需幾分鐘的(de)(de)(de)時(shi)間就能(neng)完成加油。如(ru)果想得(de)到美國消費者(zhe)的(de)(de)(de)廣泛接受，那么電(dian)(dian)(dian)動(dong)(dong)(dong)汽(qi)車(che)必須延長行(xing)駛(shi)距(ju)(ju)離和(he)/或縮(suo)短再充電(dian)(dian)(dian)時(shi)間。應運(yun)而(er)生的(de)(de)(de)解決方案是“油電(dian)(dian)(dian)混(hun)合(he)動(dong)(dong)(dong)力車(che)”，它把燃油引擎(qing)(qing)和(he)電(dian)(dian)(dian)動(dong)(dong)(dong)傳動(dong)(dong)(dong)系統組合(he)起來，以(yi)提供足夠的(de)(de)(de)行(xing)駛(shi)距(ju)(ju)離，同(tong)時(shi)仍然擁有綠(lv)色能(neng)源的(de)(de)(de)大多(duo)數好處。油電(dian)(dian)(dian)混(hun)合(he)動(dong)(dong)(dong)力車(che)采用車(che)載燃氣(qi)引擎(qing)(qing)(用于(yu)電(dian)(dian)(dian)池(chi)充電(dian)(dian)(dian))，并在(zai)需要(yao)時(shi)在(zai)最有效(xiao)的(de)(de)(de)速度/轉矩范圍(wei)內(nei)操作該引擎(qing)(qing)。

毫(hao)無疑問，電(dian)(dian)動汽車的(de)(de)成功將(jiang)(jiang)有助(zhu)于其(qi)它應用的(de)(de)高性(xing)能(neng)電(dian)(dian)池(chi)系(xi)統(tong)找到(dao)屬于自己的(de)(de)生存空間(jian)，從而推進其(qi)價(jia)格的(de)(de)下降和(he)性(xing)能(neng)的(de)(de)提(ti)升。對(dui)于局部發電(dian)(dian)(包括小型(xing)光伏或風力發電(dian)(dian)系(xi)統(tong))，電(dian)(dian)池(chi)可以(yi)起到(dao)至(zhi)關重要的(de)(de)平衡作用，且(qie)當可以(yi)使用電(dian)(dian)網電(dian)(dian)力時，它還能(neng)充當一個后備(bei)電(dian)(dian)源系(xi)統(tong)。目前的(de)(de)電(dian)(dian)池(chi)系(xi)統(tong)相當昂貴而且(qie)龐大，且(qie)存在可靠(kao)性(xing)和(he)安全方面(mian)的(de)(de)問題(ti)。下一代電(dian)(dian)池(chi)系(xi)統(tong)將(jiang)(jiang)提(ti)供較(jiao)高的(de)(de)能(neng)量密度(du)，旨在實現外形(xing)較(jiao)小、價(jia)格較(jiao)低、可靠(kao)性(xing)和(he)安全性(xing)更高的(de)(de)解決方案(an)。

高電壓電池組的設計挑戰(zhan)

       對于大功率電池應用而言，鋰離電池可(ke)作為首選的化(hua)學電(dian)(dian)池，主要因(yin)為它(ta)的能(neng)量密(mi)(mi)度(du)高(gao)。當今的電(dian)(dian)動汽車(che)和(he)油(you)電(dian)(dian)混合動力車(che)采用的是(shi)NiMH電(dian)(dian)池，如果采用鋰(li)離子電(dian)(dian)池將(jiang)使其能(neng)量儲存密(mi)(mi)度(du)提高(gao)400%。然而，為了使鋰(li)離子電(dian)(dian)池在多達(da)數千次的充放電(dian)(dian)循(xun)環(huan)過程(cheng)中(zhong)保持可(ke)靠，電(dian)(dian)池系統必須解決(jue)諸多技術(shu)難題。

鋰離子電池的性能取決于電池溫度和使用期限、電池充電和放電速率以及充電狀態(SOC)。這些因素并不是獨立的。例如：鋰離子電池在放電時將產生熱量，從而增加放電電流。這有可能形成熱失控狀態，并導致災難性故障的發生。此外，把鋰離子電池充(chong)電(dian)(dian)(dian)(dian)至100% SOC或放電(dian)(dian)(dian)(dian)至0% SOC將迅速降低(di)其容量。因此(ci)(ci)，必(bi)須將鋰離子電(dian)(dian)(dian)(dian)池(chi)的(de)(de)(de)操作(zuo)限(xian)制在某個SOC范圍(wei)內，比如20%至80%，此(ci)(ci)時(shi)的(de)(de)(de)可(ke)用(yong)容量僅(jin)為(wei)(wei)規定容量的(de)(de)(de)60%。不僅(jin)如此(ci)(ci)，鋰離子電(dian)(dian)(dian)(dian)池(chi)還具有平坦的(de)(de)(de)放電(dian)(dian)(dian)(dian)曲線(圖1)，其中1%的(de)(de)(de)SOC變化可(ke)能(neng)僅(jin)表現(xian)為(wei)(wei)數毫伏的(de)(de)(de)電(dian)(dian)(dian)(dian)壓(ya)差(cha)異。為(wei)(wei)充(chong)分(fen)利用(yong)電(dian)(dian)(dian)(dian)池(chi)的(de)(de)(de)可(ke)用(yong)電(dian)(dian)(dian)(dian)壓(ya)范圍(wei)，電(dian)(dian)(dian)(dian)池(chi)系統(tong)必(bi)須非常準確地(di)監(jian)視(shi)電(dian)(dian)(dian)(dian)池(chi)電(dian)(dian)(dian)(dian)壓(ya)(它直接對應于SOC)。

除了鋰離(li)子電(dian)(dian)(dian)池(chi)的(de)(de)敏感(gan)特性(xing)之外，把(ba)電(dian)(dian)(dian)池(chi)組合在(zai)一(yi)起的(de)(de)方(fang)法也是一(yi)個重要的(de)(de)考慮因素。如欲從一(yi)個電(dian)(dian)(dian)氣系(xi)統(比如用于(yu)給車輛(liang)加(jia)速(su)所需的(de)(de)電(dian)(dian)(dian)氣系(xi)統)來(lai)提供(gong)有(you)效的(de)(de)功(gong)率，則(ze)需高達(da)數百(bai)伏的(de)(de)電(dian)(dian)(dian)壓。舉例來(lai)說(shuo)，在(zai)1V電(dian)(dian)(dian)壓條件下(xia)輸送(song)1kW功(gong)率需要1,000A電(dian)(dian)(dian)流(liu)，而在(zai)100V電(dian)(dian)(dian)壓條件下(xia)輸送(song)1kW功(gong)率則(ze)僅需10A電(dian)(dian)(dian)流(liu)。系(xi)統布線(xian)和互連線(xian)中的(de)(de)固(gu)有(you)電(dian)(dian)(dian)阻將轉換(huan)成IR損(sun)耗，因此設計師需采(cai)用切實可行的(de)(de)最高電(dian)(dian)(dian)壓/最低電(dian)(dian)(dian)流(liu)。