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Charging SLAs from DC Answered

Hi Instructables community!

I am building a K9 robot - one that is going to be covered in solar cells-in such a way that I get a voltage / current ratio of a pretty high number. I plan to charge my SLA partially via these cells so I can lengthen the space between charges. Unfortunately, my 6V 4.5Ah SLA battery is charged via a plugin adapter and I do not wish to pull it apart unless there is no other choice - so is there are a way I can charge my battery from a constant DC voltage? If so, do any of you know what voltage/currents I'd need to feed it?

I can get most any current/voltage specs via transistors and voltage boosters - just I don't know the equation.

Thanks for all your help!
Jonathan Davis
NitroJon Labs



1 year ago

6.6 to 7.2V is a good value.
But using just unregulated DC is not the best option to keep your battery fit.
IMHO the best option would be to wast the 5 bucks and order a 6V solr battery charge controller from Fleabuy or similar.
Connect the battery and the load plus you DC for charging, in this case it can be anything from aorund 8V to over 20V - so you might have a suitable supply collecting dust somewhere already.
By using the controller you avoid the troubles of creating your own protection circuit, charge regulator and so on, will cost more if you buy the required parts than getting it as a whole from china ;)