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)壓是干電(dian)(dian)池(chi)性能的(de)(de)(de)重要性能指標(biao)之一(yi)(yi)，它(ta)表示干電(dian)(dian)池(chi)在一(yi)(yi)定狀態(tai)下電(dian)(dian)池(chi)兩端(duan)的(de)(de)(de)電(dian)(dian)勢差，一(yi)(yi)般干電(dian)(dian)池(chi)的(de)(de)(de)電(dian)(dian)壓有三種：

1、標準電壓

又稱額定電(dian)壓，指電(dian)池正負(fu)極(ji)材料因(yin)化(hua)學反(fan)應而造成的電(dian)位差，由此產生的電(dian)壓值。干電(dian)池的標準電(dian)壓為1.5V。

普(pu)通(tong)干電(dian)(dian)(dian)池內部(bu)的(de)化(hua)(hua)學電(dian)(dian)(dian)解液反應的(de)激烈(lie)程度只(zhi)能(neng)達到使(shi)電(dian)(dian)(dian)池發揮(hui)出約(yue)(yue)1.5V的(de)電(dian)(dian)(dian)壓水平。這個電(dian)(dian)(dian)壓跟化(hua)(hua)學離子(zi)化(hua)(hua)傾向有(you)關，也就是說跟陰極和陽極材料有(you)關，鋅跟碳(tan)棒(bang)在(zai)電(dian)(dian)(dian)解液中產生的(de)電(dian)(dian)(dian)勢(shi)就是大約(yue)(yue)1.5伏特(te)。

2、開路電壓

指電(dian)(dian)池(chi)在非工作狀(zhuang)態下即(ji)電(dian)(dian)路中(zhong)無電(dian)(dian)流流過時(shi)，電(dian)(dian)池(chi)正負極之間的(de)電(dian)(dian)勢(shi)差。干電(dian)(dian)池(chi)滿電(dian)(dian)時(shi)的(de)開路電(dian)(dian)壓為(wei)1.65~1.725V。

3、工作電壓

又(you)稱端電壓(ya)，是指電池(chi)在(zai)工作狀態下即電路(lu)中有電流(liu)(liu)流(liu)(liu)過時電池(chi)正負極(ji)之(zhi)間的(de)電勢差。在(zai)電池(chi)放(fang)電工作狀態下，當電流(liu)(liu)流(liu)(liu)過電池(chi)內(nei)部時，需克服(fu)電池(chi)的(de)內(nei)阻(zu)所造成阻(zu)力，故工作電壓(ya)總是低于開(kai)路(lu)電壓(ya)，充(chong)電時則與(yu)之(zhi)相反。

二、怎么測量干電池的電壓

選定一個適當(dang)的(de)負(fu)(fu)載(zai)(zai)電(dian)(dian)(dian)(dian)(dian)阻(zu)(zu)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)壓跟剩余電(dian)(dian)(dian)(dian)(dian)量(liang)存在某種已知關系，所以根(gen)據電(dian)(dian)(dian)(dian)(dian)池(chi)的(de)容(rong)量(liang)及用途,再測(ce)量(liang)電(dian)(dian)(dian)(dian)(dian)阻(zu)(zu)兩(liang)端電(dian)(dian)(dian)(dian)(dian)壓，看此(ci)時(shi)電(dian)(dian)(dian)(dian)(dian)池(chi)在帶負(fu)(fu)荷時(shi)電(dian)(dian)(dian)(dian)(dian)壓較空載(zai)(zai)時(shi)下降程度，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(jian)是不(bu)施(shi)(shi)加任何負(fu)(fu)載(zai)(zai)的(de)情況下，加負(fu)(fu)載(zai)(zai)后，電(dian)(dian)(dian)(dian)(dian)池(chi)電(dian)(dian)(dian)(dian)(dian)壓會(hui)因為內(nei)部(bu)阻(zu)(zu)抗引起壓降失真，并隨時(shi)間的(de)推(tui)移以不(bu)同(tong)速率(lv)逐漸降低，并且在去除(chu)負(fu)(fu)載(zai)(zai)后逐漸升高。因此(ci)如果施(shi)(shi)加負(fu)(fu)載(zai)(zai)的(de)話，會(hui)影響干(gan)電(dian)(dian)(dian)(dian)(dian)池(chi)電(dian)(dian)(dian)(dian)(dian)量(liang)的(de)檢測(ce)結(jie)果。

萬(wan)用(yong)表(biao)(biao)(biao)(biao)也可以(yi)準(zhun)確測量干(gan)(gan)電(dian)(dian)(dian)(dian)池(chi)(chi)的(de)電(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)，通(tong)過測量干(gan)(gan)電(dian)(dian)(dian)(dian)池(chi)(chi)電(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)的(de)高(gao)低，對電(dian)(dian)(dian)(dian)量進行(xing)判斷，如果(guo)測量電(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)不小于干(gan)(gan)電(dian)(dian)(dian)(dian)池(chi)(chi)的(de)標注(zhu)電(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)時，說(shuo)明干(gan)(gan)電(dian)(dian)(dian)(dian)池(chi)(chi)的(de)電(dian)(dian)(dian)(dian)量是(shi)(shi)充足的(de)；小于干(gan)(gan)電(dian)(dian)(dian)(dian)池(chi)(chi)的(de)標注(zhu)電(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)越多，說(shuo)明干(gan)(gan)電(dian)(dian)(dian)(dian)池(chi)(chi)虧電(dian)(dian)(dian)(dian)越多，由于型號的(de)不同干(gan)(gan)電(dian)(dian)(dian)(dian)池(chi)(chi)的(de)檢測結果(guo)會受到影響，但是(shi)(shi)對單(dan)節(jie)干(gan)(gan)電(dian)(dian)(dian)(dian)池(chi)(chi)來說(shuo)，只要使用(yong)是(shi)(shi)普通(tong)指針式萬(wan)能表(biao)(biao)(biao)(biao)，將萬(wan)能表(biao)(biao)(biao)(biao)選最(zui)大電(dian)(dian)(dian)(dian)流檔（0.5A-1A），負(fu)表(biao)(biao)(biao)(biao)筆(bi)(bi)接電(dian)(dian)(dian)(dian)池(chi)(chi)負(fu)極，正表(biao)(biao)(biao)(biao)筆(bi)(bi)在(zai)電(dian)(dian)(dian)(dian)池(chi)(chi)正極上迅速(su)碰(peng)一下，注(zhu)意觀(guan)察(cha)表(biao)(biao)(biao)(biao)針運動（短路(lu)電(dian)(dian)(dian)(dian)流）情況，便知道電(dian)(dian)(dian)(dian)池(chi)(chi)還剩多少電(dian)(dian)(dian)(dian)量了。

三、干電池電壓低于多少伏就不能用了

干電(dian)(dian)池(chi)的(de)電(dian)(dian)壓(ya)會隨著使用時(shi)間(jian)的(de)增加不斷下降，下降到一定(ding)程度就(jiu)不能用了，一般情況下，干電(dian)(dian)池(chi)的(de)電(dian)(dian)壓(ya)降至(zhi)1.0V ~ 1.2V時(shi)，就(jiu)可以視為(wei)干電(dian)(dian)池(chi)即將沒(mei)電(dian)(dian)，這時(shi)的(de)干電(dian)(dian)池(chi)已經不能滿足大(da)部分電(dian)(dian)子設(she)備的(de)工作需求，需要更換干電(dian)(dian)池(chi)。