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，干電池電壓是(shi)干(gan)電池(chi)性能(neng)的重要性能(neng)指標之一，它表示干(gan)電池(chi)在一定(ding)狀態下電池(chi)兩端的電勢差，一般干(gan)電池(chi)的電壓有三種(zhong)：

1、標準電壓

又稱額定電(dian)(dian)壓，指電(dian)(dian)池(chi)正負(fu)極材料因(yin)化(hua)學反應而造成的(de)電(dian)(dian)位差，由此產生的(de)電(dian)(dian)壓值。干電(dian)(dian)池(chi)的(de)標準電(dian)(dian)壓為1.5V。

普通干(gan)電池內部(bu)的化學電解液反應的激烈程度(du)只能達(da)到使電池發(fa)揮出約(yue)1.5V的電壓水平(ping)。這個電壓跟化學離(li)子(zi)化傾向有(you)關，也(ye)就是說跟陰極和陽極材料(liao)有(you)關，鋅跟碳棒在(zai)電解液中產生的電勢就是大約(yue)1.5伏特。

2、開路電壓

指電(dian)(dian)(dian)池在非工作狀(zhuang)態下(xia)即(ji)電(dian)(dian)(dian)路中無電(dian)(dian)(dian)流流過時，電(dian)(dian)(dian)池正負極之間的(de)電(dian)(dian)(dian)勢差。干電(dian)(dian)(dian)池滿電(dian)(dian)(dian)時的(de)開路電(dian)(dian)(dian)壓為1.65~1.725V。

3、工作電壓

又稱(cheng)端電(dian)(dian)(dian)(dian)壓(ya)，是指電(dian)(dian)(dian)(dian)池(chi)(chi)在工作狀(zhuang)態下即電(dian)(dian)(dian)(dian)路中有電(dian)(dian)(dian)(dian)流流過時(shi)電(dian)(dian)(dian)(dian)池(chi)(chi)正(zheng)負極之(zhi)間的電(dian)(dian)(dian)(dian)勢差。在電(dian)(dian)(dian)(dian)池(chi)(chi)放(fang)電(dian)(dian)(dian)(dian)工作狀(zhuang)態下，當電(dian)(dian)(dian)(dian)流流過電(dian)(dian)(dian)(dian)池(chi)(chi)內部時(shi)，需克(ke)服電(dian)(dian)(dian)(dian)池(chi)(chi)的內阻所造成阻力，故工作電(dian)(dian)(dian)(dian)壓(ya)總是低于開路電(dian)(dian)(dian)(dian)壓(ya)，充電(dian)(dian)(dian)(dian)時(shi)則與之(zhi)相反。

二、怎么測量干電池的電壓

選定一(yi)個適(shi)當的(de)負(fu)(fu)載(zai)電(dian)(dian)(dian)(dian)(dian)阻并聯在電(dian)(dian)(dian)(dian)(dian)池(chi)的(de)正負(fu)(fu)極間，電(dian)(dian)(dian)(dian)(dian)池(chi)電(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)跟剩(sheng)余(yu)電(dian)(dian)(dian)(dian)(dian)量(liang)存在某種已知關(guan)系(xi)，所以根據(ju)電(dian)(dian)(dian)(dian)(dian)池(chi)的(de)容量(liang)及(ji)用途(tu),再(zai)測(ce)量(liang)電(dian)(dian)(dian)(dian)(dian)阻兩端電(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)，看此時電(dian)(dian)(dian)(dian)(dian)池(chi)在帶(dai)負(fu)(fu)荷時電(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)較空載(zai)時下(xia)降(jiang)程度，就可以判斷電(dian)(dian)(dian)(dian)(dian)池(chi)的(de)電(dian)(dian)(dian)(dian)(dian)量(liang)；不(bu)過前提條件是不(bu)施加任何負(fu)(fu)載(zai)的(de)情(qing)況下(xia)，加負(fu)(fu)載(zai)后，電(dian)(dian)(dian)(dian)(dian)池(chi)電(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)會因為內部阻抗引(yin)起壓(ya)(ya)降(jiang)失真，并隨時間的(de)推(tui)移以不(bu)同速率逐漸降(jiang)低，并且在去除負(fu)(fu)載(zai)后逐漸升高。因此如果施加負(fu)(fu)載(zai)的(de)話(hua)，會影(ying)響干電(dian)(dian)(dian)(dian)(dian)池(chi)電(dian)(dian)(dian)(dian)(dian)量(liang)的(de)檢測(ce)結果。

萬(wan)用表也(ye)可(ke)以準確測量干(gan)電(dian)(dian)(dian)池的(de)電(dian)(dian)(dian)壓(ya)(ya)，通過測量干(gan)電(dian)(dian)(dian)池電(dian)(dian)(dian)壓(ya)(ya)的(de)高(gao)低(di)，對電(dian)(dian)(dian)量進行判斷，如果測量電(dian)(dian)(dian)壓(ya)(ya)不小于干(gan)電(dian)(dian)(dian)池的(de)標注電(dian)(dian)(dian)壓(ya)(ya)時，說(shuo)明干(gan)電(dian)(dian)(dian)池的(de)電(dian)(dian)(dian)量是(shi)(shi)充足的(de)；小于干(gan)電(dian)(dian)(dian)池的(de)標注電(dian)(dian)(dian)壓(ya)(ya)越多，說(shuo)明干(gan)電(dian)(dian)(dian)池虧電(dian)(dian)(dian)越多，由于型號的(de)不同干(gan)電(dian)(dian)(dian)池的(de)檢測結果會(hui)受到影響(xiang)，但是(shi)(shi)對單節干(gan)電(dian)(dian)(dian)池來說(shuo)，只要使用是(shi)(shi)普通指針(zhen)式萬(wan)能表，將萬(wan)能表選最(zui)大電(dian)(dian)(dian)流檔（0.5A-1A），負表筆接電(dian)(dian)(dian)池負極，正(zheng)表筆在(zai)電(dian)(dian)(dian)池正(zheng)極上(shang)迅速碰(peng)一下，注意觀察表針(zhen)運動（短路電(dian)(dian)(dian)流）情況，便知道電(dian)(dian)(dian)池還剩多少(shao)電(dian)(dian)(dian)量了。

三、干電池電壓低于多少伏就不能用了

干(gan)(gan)電池(chi)的(de)(de)電壓(ya)會隨(sui)著使用時間的(de)(de)增(zeng)加不(bu)斷下降(jiang)，下降(jiang)到(dao)一定程度就(jiu)不(bu)能用了，一般情(qing)況下，干(gan)(gan)電池(chi)的(de)(de)電壓(ya)降(jiang)至1.0V ~ 1.2V時，就(jiu)可以視為干(gan)(gan)電池(chi)即將沒電，這時的(de)(de)干(gan)(gan)電池(chi)已經不(bu)能滿足大部分電子(zi)設備的(de)(de)工作需求，需要更換干(gan)(gan)電池(chi)。