檢測普(pu)通(tong)鋅錳干電(dian)(dian)(dian)(dian)池(chi)(chi)的(de)電(dian)(dian)(dian)(dian)量(liang)是否充(chong)足，通(tong)常有兩(liang)種方(fang)法(fa)。第一(yi)種方(fang)法(fa)是通(tong)過測量(liang)電(dian)(dian)(dian)(dian)池(chi)(chi)瞬時(shi)短路電(dian)(dian)(dian)(dian)流(liu)來估算(suan)電(dian)(dian)(dian)(dian)池(chi)(chi)的(de)內阻，進而(er)判(pan)斷(duan)電(dian)(dian)(dian)(dian)池(chi)(chi)電(dian)(dian)(dian)(dian)量(liang)是否充(chong)足；第二種方(fang)法(fa)是用電(dian)(dian)(dian)(dian)流(liu)表串聯一(yi)只阻值適當的(de)電(dian)(dian)(dian)(dian)阻，通(tong)過測量(liang)電(dian)(dian)(dian)(dian)池(chi)(chi)的(de)放電(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)流(liu)計算(suan)出電(dian)(dian)(dian)(dian)池(chi)(chi)內阻，從而(er)判(pan)斷(duan)電(dian)(dian)(dian)(dian)池(chi)(chi)電(dian)(dian)(dian)(dian)量(liang)是否充(chong)足。

第一種方法的最大優點是簡便，用萬用表的大電流檔就可直接判斷出干電池的電量，缺點是測試電流很大，遠遠超過干電池允許放電電流的極限值，在一定程度上影響干電池使用壽命。第二種方法的優點是測試電流小，安全性好，一般不會對干電池的使用壽命產生不良影響，缺點是較為麻煩。
筆者用MF47型萬用表對一節新2號干(gan)電(dian)(dian)(dian)池(chi)和一節舊2號干(gan)電(dian)(dian)(dian)池(chi)分(fen)別用上述兩種方(fang)法進行測試(shi)對比。假設(she)ro是(shi)干(gan)電(dian)(dian)(dian)池(chi)內阻，RO是(shi)電(dian)(dian)(dian)流表內阻，用第二種測試(shi)方(fang)法時，RF是(shi)附加的串聯(lian)電(dian)(dian)(dian)阻，阻值3Ω，功率2W。

      實測(ce)(ce)結果(guo)如下。新2號電(dian)(dian)(dian)池E=1.58V（用(yong)2.5V直流電(dian)(dian)(dian)壓(ya)檔測(ce)(ce)量(liang)），電(dian)(dian)(dian)壓(ya)表內阻為(wei)50kΩ，遠大于ro，故可近似認為(wei)1.58V是電(dian)(dian)(dian)池的(de)電(dian)(dian)(dian)動(dong)勢(shi)，或稱開路電(dian)(dian)(dian)壓(ya)。用(yong)第(di)一種(zhong)方(fang)法(fa)時(shi)，萬(wan)用(yong)表置5A直流電(dian)(dian)(dian)流檔，電(dian)(dian)(dian)表內阻RO=0.06Ω，測(ce)(ce)得電(dian)(dian)(dian)流為(wei)3.3A。所以(yi) ro+RO=1.58V÷3.3A≈0.48Ω，ro=0.48-0.06=0.42Ω。用(yong)第(di)二(er)種(zhong)方(fang)法(fa)時(shi)，測(ce)(ce)得電(dian)(dian)(dian)流為(wei) 0.395A，RF+ro+RO=1.58V÷0.395A=4Ω，電(dian)(dian)(dian)流500mA檔內阻為(wei)0.6Ω，所以(yi)ro=4-3-0.6=0.4Ω。

舊2號電池用第一種方法測量時，先測得開路電壓E=1.2V，電表內阻RO=6Ω，讀數為6.5mA，萬用表置50mA直流電流檔，ro+RO=1.2V÷0.0065A≈184.6Ω，ro=184.6-6=178.6Ω。用第二種方法，測得電流為 6.3mA，ro+RO+RF=1.2V÷0.0063A=190.5Ω，ro=190.5-6-3=181.5Ω。
顯(xian)然兩種測(ce)試(shi)方(fang)法的(de)結果(guo)(guo)基本一(yi)致(zhi)。最終計算結果(guo)(guo)的(de)微小差(cha)別是由于讀數誤差(cha)、電阻RF的(de)誤差(cha)以及(ji)接觸電阻等多方(fang)面因素造成的(de)，這(zhe)種微小誤差(cha)不致(zhi)影響對電池電量的(de)判斷。如(ru)(ru)果(guo)(guo)被測(ce)電池的(de)容量小、電壓高（例如(ru)(ru)15V、9V疊層電池），則(ze)應將RF的(de)阻值適應增大(da)。