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，干電池電壓是干(gan)電池(chi)性能的重(zhong)要性能指標之一，它表示干(gan)電池(chi)在一定狀態下(xia)電池(chi)兩(liang)端(duan)的電勢差，一般干(gan)電池(chi)的電壓有三種：

1、標準電壓

又(you)稱(cheng)額定電(dian)(dian)壓，指電(dian)(dian)池(chi)正負極材料因化(hua)學反應而造(zao)成的(de)電(dian)(dian)位差，由(you)此(ci)產生的(de)電(dian)(dian)壓值。干(gan)電(dian)(dian)池(chi)的(de)標準電(dian)(dian)壓為1.5V。

普通(tong)干電(dian)(dian)池(chi)內部的(de)(de)化(hua)(hua)學電(dian)(dian)解液(ye)反應的(de)(de)激烈(lie)程度只能達(da)到使電(dian)(dian)池(chi)發揮出約(yue)1.5V的(de)(de)電(dian)(dian)壓水平。這個電(dian)(dian)壓跟化(hua)(hua)學離子化(hua)(hua)傾向有關，也就是(shi)說(shuo)跟陰極(ji)和(he)陽極(ji)材料(liao)有關，鋅跟碳棒在電(dian)(dian)解液(ye)中(zhong)產生的(de)(de)電(dian)(dian)勢就是(shi)大約(yue)1.5伏(fu)特。

2、開路電壓

指電(dian)(dian)(dian)池在非工作狀態(tai)下即電(dian)(dian)(dian)路中無電(dian)(dian)(dian)流流過(guo)時，電(dian)(dian)(dian)池正負極之間的電(dian)(dian)(dian)勢差。干(gan)電(dian)(dian)(dian)池滿(man)電(dian)(dian)(dian)時的開路電(dian)(dian)(dian)壓為1.65~1.725V。

3、工作電壓

又稱端(duan)電(dian)(dian)(dian)壓，是(shi)指電(dian)(dian)(dian)池(chi)在工(gong)作狀(zhuang)態(tai)下(xia)(xia)即(ji)電(dian)(dian)(dian)路中有電(dian)(dian)(dian)流(liu)流(liu)過時電(dian)(dian)(dian)池(chi)正負極之(zhi)間的(de)電(dian)(dian)(dian)勢差。在電(dian)(dian)(dian)池(chi)放電(dian)(dian)(dian)工(gong)作狀(zhuang)態(tai)下(xia)(xia)，當電(dian)(dian)(dian)流(liu)流(liu)過電(dian)(dian)(dian)池(chi)內部時，需克服電(dian)(dian)(dian)池(chi)的(de)內阻(zu)所造成阻(zu)力，故工(gong)作電(dian)(dian)(dian)壓總是(shi)低于(yu)開路電(dian)(dian)(dian)壓，充電(dian)(dian)(dian)時則與之(zhi)相反。

二、怎么測量干電池的電壓

選(xuan)定(ding)一個適(shi)當(dang)的(de)(de)負(fu)載(zai)電(dian)阻(zu)并(bing)(bing)聯在(zai)(zai)電(dian)池(chi)(chi)的(de)(de)正負(fu)極間(jian)，電(dian)池(chi)(chi)電(dian)壓(ya)(ya)跟剩余電(dian)量存(cun)在(zai)(zai)某種已知關系，所以根據(ju)電(dian)池(chi)(chi)的(de)(de)容量及(ji)用(yong)途,再測量電(dian)阻(zu)兩端電(dian)壓(ya)(ya)，看此(ci)時(shi)(shi)電(dian)池(chi)(chi)在(zai)(zai)帶負(fu)荷時(shi)(shi)電(dian)壓(ya)(ya)較(jiao)空載(zai)時(shi)(shi)下(xia)降程度，就可以判斷電(dian)池(chi)(chi)的(de)(de)電(dian)量；不(bu)過前提條件是不(bu)施加(jia)任何(he)負(fu)載(zai)的(de)(de)情況下(xia)，加(jia)負(fu)載(zai)后(hou)，電(dian)池(chi)(chi)電(dian)壓(ya)(ya)會(hui)因(yin)為(wei)內部阻(zu)抗引起(qi)壓(ya)(ya)降失真，并(bing)(bing)隨時(shi)(shi)間(jian)的(de)(de)推移以不(bu)同速率(lv)逐漸(jian)(jian)降低，并(bing)(bing)且在(zai)(zai)去除(chu)負(fu)載(zai)后(hou)逐漸(jian)(jian)升(sheng)高(gao)。因(yin)此(ci)如果施加(jia)負(fu)載(zai)的(de)(de)話，會(hui)影響干電(dian)池(chi)(chi)電(dian)量的(de)(de)檢(jian)測結(jie)果。

萬(wan)用表(biao)(biao)也可以準確測(ce)量(liang)干電(dian)(dian)(dian)(dian)池(chi)(chi)(chi)的(de)電(dian)(dian)(dian)(dian)壓，通(tong)過測(ce)量(liang)干電(dian)(dian)(dian)(dian)池(chi)(chi)(chi)電(dian)(dian)(dian)(dian)壓的(de)高低，對電(dian)(dian)(dian)(dian)量(liang)進行判(pan)斷(duan)，如果測(ce)量(liang)電(dian)(dian)(dian)(dian)壓不(bu)小于干電(dian)(dian)(dian)(dian)池(chi)(chi)(chi)的(de)標注電(dian)(dian)(dian)(dian)壓時，說明干電(dian)(dian)(dian)(dian)池(chi)(chi)(chi)的(de)電(dian)(dian)(dian)(dian)量(liang)是(shi)充足的(de)；小于干電(dian)(dian)(dian)(dian)池(chi)(chi)(chi)的(de)標注電(dian)(dian)(dian)(dian)壓越多，說明干電(dian)(dian)(dian)(dian)池(chi)(chi)(chi)虧電(dian)(dian)(dian)(dian)越多，由于型號(hao)的(de)不(bu)同干電(dian)(dian)(dian)(dian)池(chi)(chi)(chi)的(de)檢測(ce)結果會(hui)受到影響，但是(shi)對單(dan)節干電(dian)(dian)(dian)(dian)池(chi)(chi)(chi)來(lai)說，只(zhi)要(yao)使(shi)用是(shi)普(pu)通(tong)指針式(shi)萬(wan)能(neng)(neng)表(biao)(biao)，將萬(wan)能(neng)(neng)表(biao)(biao)選最(zui)大電(dian)(dian)(dian)(dian)流檔（0.5A-1A），負(fu)表(biao)(biao)筆(bi)接電(dian)(dian)(dian)(dian)池(chi)(chi)(chi)負(fu)極，正表(biao)(biao)筆(bi)在電(dian)(dian)(dian)(dian)池(chi)(chi)(chi)正極上迅速(su)碰一(yi)下，注意觀察表(biao)(biao)針運動（短(duan)路(lu)電(dian)(dian)(dian)(dian)流）情(qing)況，便知道電(dian)(dian)(dian)(dian)池(chi)(chi)(chi)還剩多少電(dian)(dian)(dian)(dian)量(liang)了。

三、干電池電壓低于多少伏就不能用了

干電(dian)(dian)池的電(dian)(dian)壓會隨著使用(yong)時(shi)間(jian)的增(zeng)加不斷下(xia)降(jiang)，下(xia)降(jiang)到一定程度就不能用(yong)了，一般情(qing)況下(xia)，干電(dian)(dian)池的電(dian)(dian)壓降(jiang)至1.0V ~ 1.2V時(shi)，就可以視為(wei)干電(dian)(dian)池即將沒電(dian)(dian)，這時(shi)的干電(dian)(dian)池已經不能滿足大(da)部分電(dian)(dian)子設備(bei)的工(gong)作需求，需要更換干電(dian)(dian)池。