一、一節干電池的電壓是多少伏

干電池是一種伏打電池，常用作手電筒照明、收音機等的電源，干電池電(dian)壓是干(gan)電(dian)池(chi)性(xing)能(neng)(neng)的重要性(xing)能(neng)(neng)指標(biao)之一，它表(biao)示干(gan)電(dian)池(chi)在一定狀態下電(dian)池(chi)兩端的電(dian)勢差，一般干(gan)電(dian)池(chi)的電(dian)壓有三種：

1、標準電壓

又稱(cheng)額(e)定電壓(ya)，指(zhi)電池(chi)正(zheng)負(fu)極材(cai)料因化學反應(ying)而造成的(de)(de)電位(wei)差，由(you)此產生的(de)(de)電壓(ya)值。干電池(chi)的(de)(de)標準電壓(ya)為(wei)1.5V。

普通干電池內(nei)部的化(hua)學電解液反(fan)應的激烈程度只能(neng)達到使電池發(fa)揮出(chu)約1.5V的電壓(ya)水平。這個電壓(ya)跟化(hua)學離子(zi)化(hua)傾向有關，也就(jiu)是說(shuo)跟陰極和(he)陽極材料有關，鋅(xin)跟碳棒(bang)在電解液中產生(sheng)的電勢(shi)就(jiu)是大約1.5伏特。

2、開路電壓

指(zhi)電(dian)池在非工作狀態下即電(dian)路(lu)中無電(dian)流(liu)流(liu)過(guo)時(shi)，電(dian)池正負極(ji)之(zhi)間(jian)的電(dian)勢(shi)差(cha)。干電(dian)池滿電(dian)時(shi)的開路(lu)電(dian)壓為1.65~1.725V。

3、工作電壓

又稱端電(dian)(dian)壓(ya)(ya)(ya)，是指(zhi)電(dian)(dian)池(chi)在工作狀態下即電(dian)(dian)路中有電(dian)(dian)流流過(guo)時(shi)電(dian)(dian)池(chi)正負極之間(jian)的電(dian)(dian)勢差。在電(dian)(dian)池(chi)放電(dian)(dian)工作狀態下，當電(dian)(dian)流流過(guo)電(dian)(dian)池(chi)內(nei)部時(shi)，需克服電(dian)(dian)池(chi)的內(nei)阻所造(zao)成阻力(li)，故(gu)工作電(dian)(dian)壓(ya)(ya)(ya)總(zong)是低于開(kai)路電(dian)(dian)壓(ya)(ya)(ya)，充(chong)電(dian)(dian)時(shi)則與之相(xiang)反(fan)。

二、怎么測量干電池的電壓

選定一個(ge)適當(dang)的(de)(de)負(fu)載(zai)電(dian)阻并(bing)(bing)聯在(zai)電(dian)池(chi)的(de)(de)正負(fu)極間，電(dian)池(chi)電(dian)壓(ya)跟剩余電(dian)量(liang)存在(zai)某種已知關系，所以根據電(dian)池(chi)的(de)(de)容量(liang)及用(yong)途,再測量(liang)電(dian)阻兩端電(dian)壓(ya)，看(kan)此時電(dian)池(chi)在(zai)帶負(fu)荷時電(dian)壓(ya)較空載(zai)時下降程(cheng)度，就(jiu)可以判(pan)斷電(dian)池(chi)的(de)(de)電(dian)量(liang)；不(bu)(bu)過前(qian)提條件是不(bu)(bu)施加任(ren)何負(fu)載(zai)的(de)(de)情(qing)況下，加負(fu)載(zai)后，電(dian)池(chi)電(dian)壓(ya)會因為內部阻抗引起壓(ya)降失真，并(bing)(bing)隨時間的(de)(de)推移以不(bu)(bu)同速率(lv)逐漸降低，并(bing)(bing)且在(zai)去除負(fu)載(zai)后逐漸升高。因此如果(guo)(guo)施加負(fu)載(zai)的(de)(de)話，會影響干電(dian)池(chi)電(dian)量(liang)的(de)(de)檢測結(jie)果(guo)(guo)。

萬用表也可以準確測(ce)(ce)(ce)量(liang)(liang)干電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)的(de)(de)電(dian)(dian)(dian)(dian)(dian)(dian)壓，通過測(ce)(ce)(ce)量(liang)(liang)干電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)電(dian)(dian)(dian)(dian)(dian)(dian)壓的(de)(de)高(gao)低，對電(dian)(dian)(dian)(dian)(dian)(dian)量(liang)(liang)進行判斷，如果(guo)測(ce)(ce)(ce)量(liang)(liang)電(dian)(dian)(dian)(dian)(dian)(dian)壓不小于(yu)干電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)的(de)(de)標(biao)注電(dian)(dian)(dian)(dian)(dian)(dian)壓時(shi)，說明(ming)(ming)干電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)的(de)(de)電(dian)(dian)(dian)(dian)(dian)(dian)量(liang)(liang)是(shi)充足的(de)(de)；小于(yu)干電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)的(de)(de)標(biao)注電(dian)(dian)(dian)(dian)(dian)(dian)壓越(yue)多(duo)，說明(ming)(ming)干電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)虧電(dian)(dian)(dian)(dian)(dian)(dian)越(yue)多(duo)，由于(yu)型號的(de)(de)不同干電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)的(de)(de)檢測(ce)(ce)(ce)結果(guo)會(hui)受到影響，但(dan)是(shi)對單(dan)節干電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)來說，只要(yao)使(shi)用是(shi)普通指針式萬能(neng)表，將萬能(neng)表選最大電(dian)(dian)(dian)(dian)(dian)(dian)流(liu)檔（0.5A-1A），負表筆(bi)接(jie)電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)負極(ji)，正表筆(bi)在電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)正極(ji)上迅速碰一下，注意(yi)觀察表針運(yun)動（短(duan)路電(dian)(dian)(dian)(dian)(dian)(dian)流(liu)）情(qing)況，便知道電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)還(huan)剩多(duo)少電(dian)(dian)(dian)(dian)(dian)(dian)量(liang)(liang)了。

三、干電池電壓低于多少伏就不能用了

干(gan)(gan)(gan)電池(chi)(chi)(chi)的(de)電壓會隨著使用時(shi)間的(de)增加不斷下(xia)降(jiang)，下(xia)降(jiang)到一定程度就不能用了，一般情況下(xia)，干(gan)(gan)(gan)電池(chi)(chi)(chi)的(de)電壓降(jiang)至1.0V ~ 1.2V時(shi)，就可以視為干(gan)(gan)(gan)電池(chi)(chi)(chi)即將沒電，這時(shi)的(de)干(gan)(gan)(gan)電池(chi)(chi)(chi)已經不能滿足大部分電子設備的(de)工(gong)作需求，需要更(geng)換干(gan)(gan)(gan)電池(chi)(chi)(chi)。