鉛酸蓄電池的內(nei)阻(zu)(zu)是指蓄電(dian)池(chi)在(zai)工作時(shi),電(dian)流(liu)(liu)流(liu)(liu)過其內(nei)部所受到的阻(zu)(zu)力,一般分(fen)為交流(liu)(liu)內(nei)阻(zu)(zu)和(he)直流(liu)(liu)內(nei)阻(zu)(zu),由于充電(dian)電(dian)池(chi)內(nei)阻(zu)(zu)很小,測直流(liu)(liu)內(nei)阻(zu)(zu)時(shi)由于電(dian)極(ji)(ji)容量極(ji)(ji)化,產(chan)生極(ji)(ji)化內(nei)阻(zu)(zu),故(gu)無法測出(chu)其真(zhen)實值(zhi),而(er)測其交流(liu)(liu)內(nei)阻(zu)(zu)可免除極(ji)(ji)化內(nei)阻(zu)(zu)的影響,得出(chu)真(zhen)實的內(nei)值(zhi)。

蓄電池的容量主要是(shi)和極板(ban)上活性物質的利用率(lv)有關。而蓄電池極板(ban)上的活性物質是(shi)：二氧化鉛(qian)、鉛(qian)。

在蓄(xu)電(dian)(dian)(dian)池內(nei)部的化學(xue)反(fan)(fan)應過程中，其實質就是極板上的活性物質和稀(xi)硫酸電(dian)(dian)(dian)解液發生的電(dian)(dian)(dian)化學(xue)反(fan)(fan)應，產生電(dian)(dian)(dian)流。

在這個電(dian)(dian)(dian)化學(xue)反應過程中(zhong)，經常伴隨著一(yi)(yi)種(zhong)(zhong)學(xue)名叫“硫(liu)酸鹽(yan)化的(de)(de)”負(fu)反應，也就(jiu)是鉛和硫(liu)酸生(sheng)成(cheng)了一(yi)(yi)種(zhong)(zhong)硫(liu)酸鉛，這種(zhong)(zhong)硫(liu)酸鉛是一(yi)(yi)種(zhong)(zhong)絕緣(yuan)體(ti)(ti)，它的(de)(de)形(xing)成(cheng)必(bi)將對電(dian)(dian)(dian)池(chi)的(de)(de)充放電(dian)(dian)(dian)產生(sheng)極(ji)不(bu)(bu)好的(de)(de)影(ying)響，因為在負(fu)極(ji)板(ban)上(shang)形(xing)成(cheng)的(de)(de)硫(liu)酸鹽(yan)越(yue)(yue)多(duo)，電(dian)(dian)(dian)池(chi)的(de)(de)內阻(zu)越(yue)(yue)大，電(dian)(dian)(dian)池(chi)的(de)(de)可(ke)充放電(dian)(dian)(dian)性能越(yue)(yue)差，負(fu)極(ji)板(ban)上(shang)吸收不(bu)(bu)了正(zheng)極(ji)產生(sheng)的(de)(de)氣(qi)體(ti)(ti)，久而久之電(dian)(dian)(dian)池(chi)失效。

蓄電(dian)池內阻與容量的關系

影響鉛酸蓄電(dian)池容量的因素有(you)很(hen)多：放電(dian)率、溫(wen)度(du)、終止(zhi)電(dian)壓、極板幾何(he)尺(chi)寸、電(dian)解液濃度(du)等(deng)。

電(dian)池(chi)的內(nei)阻(zu)(zu)：歐姆(mu)電(dian)阻(zu)(zu)和極(ji)化(hua)內(nei)阻(zu)(zu)

歐姆電阻：電極材料、電解液、隔(ge)膜的電阻。

極化(hua)內阻(zu)：正負極化(hua)學反應(ying)時引(yin)起(qi)的內阻(zu)

兩(liang)(liang)者并(bing)不是直(zhi)(zhi)接影(ying)響(xiang)的(de)，而是通過(guo)影(ying)響(xiang)其(qi)他方(fang)面來影(ying)響(xiang)對方(fang)。也就是說(shuo)，兩(liang)(liang)者并(bing)沒(mei)有直(zhi)(zhi)接的(de)關系，而是通過(guo)影(ying)響(xiang)對方(fang)的(de)制(zhi)約因素來影(ying)響(xiang)對方(fang)。例如：溫度的(de)變化可以(yi)影(ying)響(xiang)到電(dian)池的(de)電(dian)解液和電(dian)阻變化。

1.電(dian)(dian)(dian)解(jie)液溫度升(sheng)高，擴(kuo)散速度增(zeng)(zeng)(zeng)加(jia)，電(dian)(dian)(dian)阻降低，電(dian)(dian)(dian)動勢(shi)增(zeng)(zeng)(zeng)加(jia)，因(yin)此電(dian)(dian)(dian)池容量及活性物(wu)質的利用率隨溫度增(zeng)(zeng)(zeng)加(jia)而增(zeng)(zeng)(zeng)加(jia)。

2.電(dian)(dian)(dian)(dian)解液溫度(du)(du)降低(di)大，黏度(du)(du)增(zeng)大，離子(zi)運動受阻(zu)，擴散能力降低(di)，電(dian)(dian)(dian)(dian)阻(zu)增(zeng)大，電(dian)(dian)(dian)(dian)化學反應阻(zu)力增(zeng)加(jia)，導(dao)致(zhi)蓄電(dian)(dian)(dian)(dian)池容量下降。

影響(xiang)蓄電(dian)池內阻的(de)因素

1.蓄電(dian)(dian)池的內(nei)(nei)阻(zu)(zu)(zu)由(you)歐姆極(ji)化(hua)(導體(ti)電(dian)(dian)阻(zu)(zu)(zu))和(he)電(dian)(dian)化(hua)學極(ji)化(hua)及濃差極(ji)化(hua)電(dian)(dian)阻(zu)(zu)(zu)三個部份組成。在充放(fang)電(dian)(dian)過程中電(dian)(dian)阻(zu)(zu)(zu)是變(bian)化(hua)的，充電(dian)(dian)過程內(nei)(nei)阻(zu)(zu)(zu)由(you)大(da)變(bian)小，反之(zhi)內(nei)(nei)阻(zu)(zu)(zu)增(zeng)加。

2.溫度(du)(du)對蓄電池內阻也(ye)頗有影(ying)響，低溫狀態如0℃以(yi)(yi)下，溫度(du)(du)每下降10℃，內阻約增大(da)15%，其中因硫酸溶液粘(zhan)度(du)(du)變大(da)，而增加了比電阻是重要的(de)原因之一。在較(jiao)高溫度(du)(du)時，如10℃以(yi)(yi)上(shang)，硫酸離(li)子的(de)擴散速(su)率提高了濃度(du)(du)極化(hua)作(zuo)用(yong)將明顯減小，極化(hua)電阻下降，但導體(ti)電阻卻隨溫度(du)(du)增加而上(shang)升(sheng)(sheng)，不過上(shang)升(sheng)(sheng)的(de)速(su)率較(jiao)小。

3.蓄(xu)電(dian)(dian)(dian)池的內阻(zu)(zu)與放(fang)電(dian)(dian)(dian)電(dian)(dian)(dian)流的大小有關，瞬間的大電(dian)(dian)(dian)流放(fang)電(dian)(dian)(dian)，由于極板(ban)空(kong)隙(xi)內的硫(liu)酸溶(rong)(rong)(rong)液(ye)迅速稀釋，而(er)極板(ban)孔外90%以上溶(rong)(rong)(rong)液(ye)中(zhong)硫(liu)酸分子來不及擴(kuo)散到極板(ban)空(kong)隙(xi)中(zhong)去。這樣(yang)，極板(ban)孔中(zhong)溶(rong)(rong)(rong)液(ye)比電(dian)(dian)(dian)阻(zu)(zu)增加，端電(dian)(dian)(dian)壓明(ming)顯下降。但(dan)停止(zhi)放(fang)電(dian)(dian)(dian)后，隨(sui)著濃度高的硫(liu)酸分子向(xiang)極板(ban)空(kong)隙(xi)中(zhong)擴(kuo)散，極板(ban)孔中(zhong)溶(rong)(rong)(rong)液(ye)比電(dian)(dian)(dian)阻(zu)(zu)下降，端電(dian)(dian)(dian)壓回升。

4.另外，薄極(ji)板的電(dian)(dian)池(chi)(chi)，其內阻明顯小(xiao)于厚極(ji)板，因為同容(rong)量電(dian)(dian)池(chi)(chi)的極(ji)板數(shu)量，薄的要多于厚極(ji)板電(dian)(dian)池(chi)(chi)的極(ji)板數(shu)量，因此(ci)相同電(dian)(dian)流(liu)放電(dian)(dian)時，薄極(ji)板電(dian)(dian)池(chi)(chi)的電(dian)(dian)流(liu)密度小(xiao)，其各(ge)極(ji)極(ji)化也要小(xiao)得多。