on board circuit to charge the SLA battery

suncq · Joined: 21 Jul 2006 Posts: 21

I have a 16f877 based datalogger project now. I need a on board circuit to charge the SLA battery(12V/7A). one project use the AC main and the other use a solar panel.Could you give me a tip and help.

thanks in advance!

rwyoung · Joined: 12 Nov 2003 Posts: 563 Location: Lawrence, KS USA

Dumb and simple: trickle charge, Google is your friend.

For a "faster" charge, you can again consult Google and do some reading but it will be more complicated than a rectifying diode and current limitter used by a trickle charger...

Depends on the particular battery (consult maufacturer's web site for recommended charging proceedures). Also, in the case of the solar panel, depends on available expcected power from the panel and what you want to happen when the power is below expected thresholds. In the case of the AC mains, depends on the particular voltage and current available on the branch in your particular country. For the small 7A battery you mentioned, this is a small consideration but you do need to size a few components appropriately.

Seriously, if you have no real expectations on charging the battery quickly, search for "trickle charge"
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Rob Young
The Screw-Up Fairy may just visit you but he has crashed on my couch for the last month!

mfer · Joined: 11 Jan 2007 Posts: 8

Hi,

Philips had a nice universal battery charger: TEA1102.
It is discontinued if I'm not mistaken, but they surely have something new.

Regards,
mfer