檢測普通鋅(xin)錳干電(dian)(dian)(dian)(dian)(dian)池(chi)(chi)的電(dian)(dian)(dian)(dian)(dian)量(liang)(liang)(liang)是(shi)(shi)(shi)否(fou)充足，通常有兩種(zhong)方法。第(di)一種(zhong)方法是(shi)(shi)(shi)通過測量(liang)(liang)(liang)電(dian)(dian)(dian)(dian)(dian)池(chi)(chi)瞬時短路電(dian)(dian)(dian)(dian)(dian)流來估算電(dian)(dian)(dian)(dian)(dian)池(chi)(chi)的內(nei)阻，進而(er)(er)判(pan)斷電(dian)(dian)(dian)(dian)(dian)池(chi)(chi)電(dian)(dian)(dian)(dian)(dian)量(liang)(liang)(liang)是(shi)(shi)(shi)否(fou)充足；第(di)二種(zhong)方法是(shi)(shi)(shi)用電(dian)(dian)(dian)(dian)(dian)流表(biao)串聯(lian)一只阻值適(shi)當的電(dian)(dian)(dian)(dian)(dian)阻，通過測量(liang)(liang)(liang)電(dian)(dian)(dian)(dian)(dian)池(chi)(chi)的放電(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)流計算出電(dian)(dian)(dian)(dian)(dian)池(chi)(chi)內(nei)阻，從而(er)(er)判(pan)斷電(dian)(dian)(dian)(dian)(dian)池(chi)(chi)電(dian)(dian)(dian)(dian)(dian)量(liang)(liang)(liang)是(shi)(shi)(shi)否(fou)充足。

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(xing)萬用表(biao)對(dui)一節(jie)新(xin)2號(hao)干電(dian)池(chi)和(he)一節(jie)舊2號(hao)干電(dian)池(chi)分別(bie)用上(shang)述兩(liang)種方(fang)法(fa)進(jin)行(xing)測試對(dui)比。假設ro是干電(dian)池(chi)內(nei)阻，RO是電(dian)流(liu)表(biao)內(nei)阻，用第二種測試方(fang)法(fa)時，RF是附(fu)加的串(chuan)聯電(dian)阻，阻值(zhi)3Ω，功率2W。

      實測(ce)結果(guo)如下。新2號電(dian)池E=1.58V（用(yong)2.5V直(zhi)流電(dian)壓檔測(ce)量），電(dian)壓表(biao)(biao)內阻(zu)為(wei)50kΩ，遠(yuan)大于ro，故(gu)可近似認(ren)為(wei)1.58V是電(dian)池的電(dian)動勢，或稱開路電(dian)壓。用(yong)第一(yi)種方法(fa)時(shi)，萬用(yong)表(biao)(biao)置(zhi)5A直(zhi)流電(dian)流檔，電(dian)表(biao)(biao)內阻(zu)RO=0.06Ω，測(ce)得(de)電(dian)流為(wei)3.3A。所以 ro+RO=1.58V÷3.3A≈0.48Ω，ro=0.48-0.06=0.42Ω。用(yong)第二種方法(fa)時(shi)，測(ce)得(de)電(dian)流為(wei) 0.395A，RF+ro+RO=1.58V÷0.395A=4Ω，電(dian)流500mA檔內阻(zu)為(wei)0.6Ω，所以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(liang)種(zhong)測(ce)試方法的(de)結(jie)果基本一致(zhi)。最終計算結(jie)果的(de)微小(xiao)差(cha)別是(shi)由于讀(du)數誤(wu)差(cha)、電(dian)(dian)(dian)阻(zu)(zu)RF的(de)誤(wu)差(cha)以及接(jie)觸電(dian)(dian)(dian)阻(zu)(zu)等(deng)多方面因(yin)素(su)造成的(de)，這種(zhong)微小(xiao)誤(wu)差(cha)不(bu)致(zhi)影響對電(dian)(dian)(dian)池電(dian)(dian)(dian)量(liang)的(de)判(pan)斷。如(ru)果被測(ce)電(dian)(dian)(dian)池的(de)容量(liang)小(xiao)、電(dian)(dian)(dian)壓高（例如(ru)15V、9V疊層電(dian)(dian)(dian)池），則應(ying)將RF的(de)阻(zu)(zu)值適(shi)應(ying)增(zeng)大(da)。