由于密封鉛酸蓄電池的諸多優點，因此獲得了廣泛應用．然而密封鉛酸蓄電池的充電技術似乎不被看重，因充電方式不合理而造成電池過早報廢的情況普遍存在．有鑒于此，筆者設計制作了一款二階段恒流限壓式鉛酸蓄電池充電器。 

電瓶(ping)充電器(qi)原(yuan)理(li)如(ru)下圖：

充電過程分析：

1.維護充電：

    當電(dian)(dian)池電(dian)(dian)壓較低時(shi)（可設定，本電(dian)(dian)路預設在9V以下），充(chong)電(dian)(dian)器(qi)工作在小電(dian)(dian)流維護充(chong)電(dian)(dian)狀態下，工作原理為U1C⑨腳(jiao)（同相端）電(dian)(dian)位(wei)低于(yu)⑧腳(jiao)（反相端），U1C輸出(chu)低電(dian)(dian)位(wei)，T4截止。U1D 11 腳(jiao)電(dian)(dian)位(wei)約0.18V．此時(shi)充(chong)電(dian)(dian)電(dian)(dian)流約250mA（恒(heng)流電(dian)(dian)路由R14，U1D，T1B周邊外圍(wei)電(dian)(dian)路構成，恒(heng)流原理讀者請自行分析）．

2. 快速充電：

    隨著維護充電繼續，電池電壓逐漸升高，當電池電壓超過9V時，充電器轉入大電流快充模式下，U1C⑨腳（同相端）電位高于⑧腳（反相端），U1C輸出高電位，T4導通，U1D 11 腳電位約為0.48V，充電器恒定輸出約1A電(dian)流給電(dian)池充電(dian)。

3. 限壓浮充：

    當電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)接近充(chong)足電(dian)(dian)(dian)(dian)(dian)(dian)時，充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)器自動(dong)轉(zhuan)入(ru)限壓浮充(chong)狀(zhuang)態下(xia)(限壓浮充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)壓設定(ding)(ding)為(wei)13.8V，如為(wei)6V蓄電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)，則浮充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)壓應設定(ding)(ding)為(wei)6.9V)， 此時的充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)(dian)流(liu)會由快(kuai)速充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)狀(zhuang)態下(xia)逐漸下(xia)降，至(zhi)電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)完全充(chong)足電(dian)(dian)(dian)(dian)(dian)(dian)后，充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)(dian)流(liu)僅為(wei)10～30mA，用以(yi)補充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)因自放電(dian)(dian)(dian)(dian)(dian)(dian)而損失的電(dian)(dian)(dian)(dian)(dian)(dian)量(liang)。

4. 保護及充電指示電路：

    本電(dian)路(lu)設有反極性保護(hu)電(dian)路(lu)，由(you)(you)D4，U1C，U1D，T1及(ji)外圍(wei)元(yuan)件構(gou)成，當電(dian)池反接時(shi)，充(chong)電(dian)器限制輸出電(dian)流不致發生事故。充(chong)電(dian)指示由(you)(you)U1A，D7及(ji)外圍(wei)元(yuan)件構(gou)成，充(chong)電(dian)時(shi)，D7點亮(liang)，充(chong)電(dian)器進(jin)入浮(fu)充(chong)狀態后，D7熄滅(mie)，表示充(chong)電(dian)結束。

5. 本電路略為修改電路參數即可任意調整充電電流，浮充電壓以滿足不同規格電池的需要。