Hi guys. I'm going to make an automatic battery charger for my 6V 4.5Ah SLA battery. This is the diagram that I've found;
**broken link removed**
I built this on breadboard, and it seems to work well, but...
As it mentioned in the document, charger starts charging the battery with charging current of about 466 mA, and current decreases as voltage of battery increases, and becomes approximately equal to zero when the battery is fully charged.
My problem is that the charging current starts from about 250 mA, and now that the voltage of battery has reached to 6.9V, it is about 70 mA. And after 48 hours, my battery isn't fully charged! Is this normal? If not, what is the problem? Is this a good circuit to use? Are all those capacitors necessary? Is there any better and faster circuit on the web? This one is the result of my search, I didn't find anything simpler and more useful.
Sorry for bad English.
and thank you beforehand.
**broken link removed**
I built this on breadboard, and it seems to work well, but...
As it mentioned in the document, charger starts charging the battery with charging current of about 466 mA, and current decreases as voltage of battery increases, and becomes approximately equal to zero when the battery is fully charged.
My problem is that the charging current starts from about 250 mA, and now that the voltage of battery has reached to 6.9V, it is about 70 mA. And after 48 hours, my battery isn't fully charged! Is this normal? If not, what is the problem? Is this a good circuit to use? Are all those capacitors necessary? Is there any better and faster circuit on the web? This one is the result of my search, I didn't find anything simpler and more useful.
Sorry for bad English.
and thank you beforehand.