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。 

電瓶充電器原理如(ru)下(xia)圖：

充電過程分析：

1.維護充電：

    當電(dian)(dian)(dian)(dian)(dian)池(chi)電(dian)(dian)(dian)(dian)(dian)壓(ya)較低(di)時（可設定，本電(dian)(dian)(dian)(dian)(dian)路預設在9V以下），充電(dian)(dian)(dian)(dian)(dian)器(qi)工作在小電(dian)(dian)(dian)(dian)(dian)流(liu)(liu)維護充電(dian)(dian)(dian)(dian)(dian)狀態下，工作原理為(wei)U1C⑨腳(jiao)（同相端）電(dian)(dian)(dian)(dian)(dian)位(wei)(wei)低(di)于⑧腳(jiao)（反(fan)相端），U1C輸出低(di)電(dian)(dian)(dian)(dian)(dian)位(wei)(wei)，T4截(jie)止(zhi)。U1D 11 腳(jiao)電(dian)(dian)(dian)(dian)(dian)位(wei)(wei)約(yue)(yue)0.18V．此時充電(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)流(liu)(liu)約(yue)(yue)250mA（恒流(liu)(liu)電(dian)(dian)(dian)(dian)(dian)路由(you)R14，U1D，T1B周邊外(wai)圍電(dian)(dian)(dian)(dian)(dian)路構成(cheng)，恒流(liu)(liu)原理讀(du)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(yue)1A電流給電池充電。

3. 限壓浮充：

    當(dang)電(dian)(dian)(dian)(dian)池接近充(chong)(chong)(chong)(chong)足電(dian)(dian)(dian)(dian)時，充(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)器自動轉入限(xian)壓(ya)浮(fu)充(chong)(chong)(chong)(chong)狀(zhuang)態下(xia)(限(xian)壓(ya)浮(fu)充(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)壓(ya)設定(ding)為(wei)13.8V，如為(wei)6V蓄電(dian)(dian)(dian)(dian)池，則浮(fu)充(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)壓(ya)應設定(ding)為(wei)6.9V)， 此時的充(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)流會(hui)由快(kuai)速充(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)狀(zhuang)態下(xia)逐漸下(xia)降，至(zhi)電(dian)(dian)(dian)(dian)池完(wan)全充(chong)(chong)(chong)(chong)足電(dian)(dian)(dian)(dian)后，充(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)流僅為(wei)10～30mA，用以補(bu)充(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)池因自放電(dian)(dian)(dian)(dian)而損失的電(dian)(dian)(dian)(dian)量。

4. 保(bao)護及充(chong)電(dian)指示電(dian)路：

    本電(dian)路設有反極性(xing)保護電(dian)路，由D4，U1C，U1D，T1及外圍元件(jian)(jian)構(gou)(gou)成(cheng)，當電(dian)池反接時，充(chong)(chong)(chong)電(dian)器(qi)限制(zhi)輸(shu)出電(dian)流不(bu)致發生事故(gu)。充(chong)(chong)(chong)電(dian)指示由U1A，D7及外圍元件(jian)(jian)構(gou)(gou)成(cheng)，充(chong)(chong)(chong)電(dian)時，D7點亮，充(chong)(chong)(chong)電(dian)器(qi)進(jin)入(ru)浮(fu)充(chong)(chong)(chong)狀態后(hou)，D7熄滅，表(biao)示充(chong)(chong)(chong)電(dian)結束(shu)。

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。