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)(dian)壓(ya)是干電(dian)(dian)池(chi)(chi)性(xing)(xing)能的重要性(xing)(xing)能指標之一，它表(biao)示干電(dian)(dian)池(chi)(chi)在一定狀態下電(dian)(dian)池(chi)(chi)兩(liang)端的電(dian)(dian)勢(shi)差(cha)，一般干電(dian)(dian)池(chi)(chi)的電(dian)(dian)壓(ya)有三(san)種：

1、標準電壓

又稱額定電(dian)(dian)壓，指(zhi)電(dian)(dian)池正負極材料因化學反應(ying)而造成的(de)電(dian)(dian)位差，由此產(chan)生的(de)電(dian)(dian)壓值。干電(dian)(dian)池的(de)標準電(dian)(dian)壓為1.5V。

普通干電(dian)(dian)池內部的化(hua)學電(dian)(dian)解(jie)液(ye)反(fan)應的激烈程度(du)只能(neng)達到(dao)使(shi)電(dian)(dian)池發揮出約1.5V的電(dian)(dian)壓(ya)水平。這個(ge)電(dian)(dian)壓(ya)跟化(hua)學離子化(hua)傾向(xiang)有關，也(ye)就(jiu)是說(shuo)跟陰極和陽極材料有關，鋅跟碳(tan)棒在電(dian)(dian)解(jie)液(ye)中產生的電(dian)(dian)勢就(jiu)是大約1.5伏特。

2、開路電壓

指電(dian)池(chi)在非工作狀態下即(ji)電(dian)路(lu)(lu)中無電(dian)流流過時，電(dian)池(chi)正負極之間(jian)的電(dian)勢差。干電(dian)池(chi)滿(man)電(dian)時的開路(lu)(lu)電(dian)壓為1.65~1.725V。

3、工作電壓

又(you)稱端(duan)電(dian)壓(ya)，是(shi)(shi)指(zhi)電(dian)池在(zai)工作狀態下(xia)即電(dian)路中有電(dian)流流過(guo)時(shi)電(dian)池正(zheng)負(fu)極之(zhi)間的電(dian)勢(shi)差。在(zai)電(dian)池放(fang)電(dian)工作狀態下(xia)，當(dang)電(dian)流流過(guo)電(dian)池內(nei)(nei)部時(shi)，需(xu)克服電(dian)池的內(nei)(nei)阻所造成阻力，故工作電(dian)壓(ya)總(zong)是(shi)(shi)低于開路電(dian)壓(ya)，充電(dian)時(shi)則與之(zhi)相反。

二、怎么測量干電池的電壓

選(xuan)定(ding)一個(ge)適當的(de)(de)(de)負(fu)(fu)載(zai)(zai)電(dian)(dian)(dian)阻并聯在電(dian)(dian)(dian)池(chi)(chi)(chi)的(de)(de)(de)正(zheng)負(fu)(fu)極間(jian)，電(dian)(dian)(dian)池(chi)(chi)(chi)電(dian)(dian)(dian)壓跟剩余電(dian)(dian)(dian)量(liang)(liang)(liang)存(cun)在某種已知(zhi)關系，所以(yi)根據電(dian)(dian)(dian)池(chi)(chi)(chi)的(de)(de)(de)容量(liang)(liang)(liang)及(ji)用(yong)途,再測量(liang)(liang)(liang)電(dian)(dian)(dian)阻兩端電(dian)(dian)(dian)壓，看此時(shi)(shi)(shi)電(dian)(dian)(dian)池(chi)(chi)(chi)在帶負(fu)(fu)荷時(shi)(shi)(shi)電(dian)(dian)(dian)壓較空(kong)載(zai)(zai)時(shi)(shi)(shi)下(xia)降(jiang)程(cheng)度，就可以(yi)判斷(duan)電(dian)(dian)(dian)池(chi)(chi)(chi)的(de)(de)(de)電(dian)(dian)(dian)量(liang)(liang)(liang)；不(bu)(bu)過前提條件(jian)是(shi)不(bu)(bu)施(shi)加任何負(fu)(fu)載(zai)(zai)的(de)(de)(de)情況下(xia)，加負(fu)(fu)載(zai)(zai)后(hou)，電(dian)(dian)(dian)池(chi)(chi)(chi)電(dian)(dian)(dian)壓會因(yin)為內(nei)部阻抗(kang)引起(qi)壓降(jiang)失(shi)真，并隨時(shi)(shi)(shi)間(jian)的(de)(de)(de)推(tui)移以(yi)不(bu)(bu)同速率逐(zhu)漸降(jiang)低，并且在去除(chu)負(fu)(fu)載(zai)(zai)后(hou)逐(zhu)漸升高。因(yin)此如果施(shi)加負(fu)(fu)載(zai)(zai)的(de)(de)(de)話，會影(ying)響干電(dian)(dian)(dian)池(chi)(chi)(chi)電(dian)(dian)(dian)量(liang)(liang)(liang)的(de)(de)(de)檢(jian)測結果。

萬(wan)(wan)用表(biao)(biao)(biao)也(ye)可以準確(que)測量干(gan)電(dian)(dian)(dian)池(chi)(chi)(chi)的電(dian)(dian)(dian)壓(ya)，通(tong)過(guo)測量干(gan)電(dian)(dian)(dian)池(chi)(chi)(chi)電(dian)(dian)(dian)壓(ya)的高低，對電(dian)(dian)(dian)量進行判斷(duan)，如果測量電(dian)(dian)(dian)壓(ya)不(bu)小于干(gan)電(dian)(dian)(dian)池(chi)(chi)(chi)的標(biao)注(zhu)(zhu)電(dian)(dian)(dian)壓(ya)時，說(shuo)明干(gan)電(dian)(dian)(dian)池(chi)(chi)(chi)的電(dian)(dian)(dian)量是充足的；小于干(gan)電(dian)(dian)(dian)池(chi)(chi)(chi)的標(biao)注(zhu)(zhu)電(dian)(dian)(dian)壓(ya)越(yue)多，說(shuo)明干(gan)電(dian)(dian)(dian)池(chi)(chi)(chi)虧電(dian)(dian)(dian)越(yue)多，由于型(xing)號(hao)的不(bu)同(tong)干(gan)電(dian)(dian)(dian)池(chi)(chi)(chi)的檢(jian)測結果會受到影響(xiang)，但是對單(dan)節干(gan)電(dian)(dian)(dian)池(chi)(chi)(chi)來說(shuo)，只(zhi)要使用是普通(tong)指(zhi)針式萬(wan)(wan)能(neng)表(biao)(biao)(biao)，將萬(wan)(wan)能(neng)表(biao)(biao)(biao)選最大電(dian)(dian)(dian)流檔（0.5A-1A），負表(biao)(biao)(biao)筆接電(dian)(dian)(dian)池(chi)(chi)(chi)負極，正表(biao)(biao)(biao)筆在(zai)電(dian)(dian)(dian)池(chi)(chi)(chi)正極上迅(xun)速碰一下，注(zhu)(zhu)意觀(guan)察(cha)表(biao)(biao)(biao)針運動(dong)（短路電(dian)(dian)(dian)流）情況，便知道電(dian)(dian)(dian)池(chi)(chi)(chi)還(huan)剩(sheng)多少電(dian)(dian)(dian)量了。

三、干電池電壓低于多少伏就不能用了

干(gan)電(dian)池的電(dian)壓(ya)會隨著使用(yong)時間(jian)的增加不斷下降，下降到一定程度就不能用(yong)了，一般情況下，干(gan)電(dian)池的電(dian)壓(ya)降至1.0V ~ 1.2V時，就可以視為(wei)干(gan)電(dian)池即將沒(mei)電(dian)，這時的干(gan)電(dian)池已經不能滿足大部分電(dian)子設備的工作需(xu)求，需(xu)要更換(huan)干(gan)電(dian)池。