Hello, thanks for reply. Then, How can I charge the battery? Do I use a bigger solar panel, 12v 10W or 6V 10W? If I use a 12V solar panel then I have to adjust the output voltage of solar panel to connect the charger. Thanks, Regards.
The battery will charge at the lower rate. Just slower.
You can use a larger panel. You can also connect multiple panels - but you should add blocking diodes to prevent reverse current through a shaded cell. Trying to regulate the voltage of a higher voltage cell would be inefficient.
I've read the info about setting the charge current but I'm confused. The Prog1 has a SMD resistor already in place that sets the current at 500ma. Adding a 2.2k resistor will, according to the page, set the current to about 950ma. Can someone tell me what configuration would provide for the maximum safe charge current?