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(ya)是干(gan)電(dian)池(chi)性能的(de)(de)重要(yao)性能指標之一(yi)，它(ta)表示干(gan)電(dian)池(chi)在一(yi)定狀(zhuang)態下電(dian)池(chi)兩(liang)端的(de)(de)電(dian)勢差，一(yi)般干(gan)電(dian)池(chi)的(de)(de)電(dian)壓(ya)有(you)三種：

1、標準電壓

又稱額定電(dian)(dian)壓(ya)(ya)，指電(dian)(dian)池(chi)正負極材料因化(hua)學反應而造成的電(dian)(dian)位差(cha)，由此產生(sheng)的電(dian)(dian)壓(ya)(ya)值(zhi)。干電(dian)(dian)池(chi)的標準電(dian)(dian)壓(ya)(ya)為1.5V。

普通干電(dian)池內部的化學(xue)電(dian)解液反應的激烈程度只(zhi)能達到(dao)使電(dian)池發(fa)揮(hui)出約(yue)1.5V的電(dian)壓(ya)(ya)水平。這個電(dian)壓(ya)(ya)跟化學(xue)離(li)子化傾向有關，也就是說(shuo)跟陰極(ji)和陽(yang)極(ji)材(cai)料(liao)有關，鋅跟碳棒在電(dian)解液中(zhong)產生的電(dian)勢就是大約(yue)1.5伏特(te)。

2、開路電壓

指電(dian)(dian)(dian)池(chi)(chi)在(zai)非工作狀態下即電(dian)(dian)(dian)路(lu)中無電(dian)(dian)(dian)流流過時(shi)，電(dian)(dian)(dian)池(chi)(chi)正負極之(zhi)間的(de)電(dian)(dian)(dian)勢差(cha)。干電(dian)(dian)(dian)池(chi)(chi)滿電(dian)(dian)(dian)時(shi)的(de)開(kai)路(lu)電(dian)(dian)(dian)壓為1.65~1.725V。

3、工作電壓

又(you)稱端電(dian)(dian)壓(ya)，是指電(dian)(dian)池(chi)在(zai)工作狀(zhuang)(zhuang)態(tai)(tai)下即電(dian)(dian)路(lu)中有電(dian)(dian)流流過時電(dian)(dian)池(chi)正負(fu)極之(zhi)間(jian)的(de)電(dian)(dian)勢(shi)差。在(zai)電(dian)(dian)池(chi)放(fang)電(dian)(dian)工作狀(zhuang)(zhuang)態(tai)(tai)下，當電(dian)(dian)流流過電(dian)(dian)池(chi)內部時，需克(ke)服電(dian)(dian)池(chi)的(de)內阻所造成阻力，故工作電(dian)(dian)壓(ya)總是低于開路(lu)電(dian)(dian)壓(ya)，充電(dian)(dian)時則與之(zhi)相反。

二、怎么測量干電池的電壓

選定(ding)一個適當的(de)(de)負(fu)載(zai)(zai)電(dian)(dian)(dian)(dian)阻(zu)并(bing)聯在(zai)(zai)電(dian)(dian)(dian)(dian)池(chi)(chi)的(de)(de)正負(fu)極間，電(dian)(dian)(dian)(dian)池(chi)(chi)電(dian)(dian)(dian)(dian)壓(ya)跟剩余(yu)電(dian)(dian)(dian)(dian)量(liang)(liang)存在(zai)(zai)某種(zhong)已知關系，所以(yi)根據(ju)電(dian)(dian)(dian)(dian)池(chi)(chi)的(de)(de)容量(liang)(liang)及用途,再測(ce)量(liang)(liang)電(dian)(dian)(dian)(dian)阻(zu)兩端電(dian)(dian)(dian)(dian)壓(ya)，看此時(shi)(shi)電(dian)(dian)(dian)(dian)池(chi)(chi)在(zai)(zai)帶負(fu)荷時(shi)(shi)電(dian)(dian)(dian)(dian)壓(ya)較空載(zai)(zai)時(shi)(shi)下(xia)降(jiang)程度(du)，就可以(yi)判斷(duan)電(dian)(dian)(dian)(dian)池(chi)(chi)的(de)(de)電(dian)(dian)(dian)(dian)量(liang)(liang)；不過前(qian)提條件(jian)是不施加(jia)任何負(fu)載(zai)(zai)的(de)(de)情況下(xia)，加(jia)負(fu)載(zai)(zai)后(hou)，電(dian)(dian)(dian)(dian)池(chi)(chi)電(dian)(dian)(dian)(dian)壓(ya)會因為內部阻(zu)抗引起壓(ya)降(jiang)失真，并(bing)隨時(shi)(shi)間的(de)(de)推移以(yi)不同速率(lv)逐(zhu)漸降(jiang)低，并(bing)且在(zai)(zai)去除負(fu)載(zai)(zai)后(hou)逐(zhu)漸升高。因此如果施加(jia)負(fu)載(zai)(zai)的(de)(de)話(hua)，會影響干(gan)電(dian)(dian)(dian)(dian)池(chi)(chi)電(dian)(dian)(dian)(dian)量(liang)(liang)的(de)(de)檢(jian)測(ce)結果。

萬用表也可以準(zhun)確測(ce)量干(gan)(gan)電(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)的(de)(de)(de)電(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)，通過(guo)測(ce)量干(gan)(gan)電(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)電(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)的(de)(de)(de)高(gao)低，對電(dian)(dian)(dian)(dian)(dian)量進行判斷，如(ru)果測(ce)量電(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)不(bu)小于(yu)干(gan)(gan)電(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)的(de)(de)(de)標(biao)注電(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)時(shi)，說明干(gan)(gan)電(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)的(de)(de)(de)電(dian)(dian)(dian)(dian)(dian)量是(shi)(shi)充足(zu)的(de)(de)(de)；小于(yu)干(gan)(gan)電(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)的(de)(de)(de)標(biao)注電(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)越(yue)(yue)多，說明干(gan)(gan)電(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)虧電(dian)(dian)(dian)(dian)(dian)越(yue)(yue)多，由于(yu)型號(hao)的(de)(de)(de)不(bu)同干(gan)(gan)電(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)的(de)(de)(de)檢測(ce)結果會受到影響，但是(shi)(shi)對單節(jie)干(gan)(gan)電(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)來說，只要使(shi)用是(shi)(shi)普通指針(zhen)式萬能(neng)表，將萬能(neng)表選(xuan)最大電(dian)(dian)(dian)(dian)(dian)流檔（0.5A-1A），負表筆接電(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)負極(ji)，正表筆在(zai)電(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)正極(ji)上(shang)迅速碰一下，注意觀察(cha)表針(zhen)運動（短路(lu)電(dian)(dian)(dian)(dian)(dian)流）情況，便知道電(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)還剩多少電(dian)(dian)(dian)(dian)(dian)量了(le)。

三、干電池電壓低于多少伏就不能用了

干電(dian)(dian)(dian)池(chi)(chi)的(de)(de)電(dian)(dian)(dian)壓會隨(sui)著使用時(shi)間的(de)(de)增加不(bu)(bu)斷下降(jiang)，下降(jiang)到(dao)一(yi)(yi)定程(cheng)度就不(bu)(bu)能(neng)用了，一(yi)(yi)般情況下，干電(dian)(dian)(dian)池(chi)(chi)的(de)(de)電(dian)(dian)(dian)壓降(jiang)至(zhi)1.0V ~ 1.2V時(shi)，就可以(yi)視(shi)為干電(dian)(dian)(dian)池(chi)(chi)即將沒(mei)電(dian)(dian)(dian)，這時(shi)的(de)(de)干電(dian)(dian)(dian)池(chi)(chi)已經(jing)不(bu)(bu)能(neng)滿足大部分(fen)電(dian)(dian)(dian)子設備的(de)(de)工(gong)作需求，需要更換干電(dian)(dian)(dian)池(chi)(chi)。