Hi, I'm making a solar project and I have a 7.5V solar panel (250mA & 1.9w) and a 6V battery (4.5Ah) .. Is it possible to charge the battery with this panel and have a protection cut-off circuit? I searched and the only circuit that I found thats close is this one but its a 12v solar panel charging a 6V battery 4.5Ah.**broken link removed**.. If I make the same circuit and change the LM317 and the resisters will it work or will I not have enough volts to charge my 6V battery?? If not is there a way not to loose the volts at the output? thank you..
With 2 diodes and a regulator, you will not get 6V on the battery from 7.5V panel. The panel may be able to rise voltage to 8V, but then it'll lose a lot of power.
With 2 diodes and a regulator, you will not get 6V on the battery from 7.5V panel. The panel may be able to rise voltage to 8V, but then it'll lose a lot of power.
You can try to design something with low voltage drop. Big mosfet for control, mechanical relay or manual switch for the night time.
If you put two panels in series they must be rated for the same current, because the panel with the least current will bring down the combined current to its level.
You can try to design something with low voltage drop. Big mosfet for control, mechanical relay or manual switch for the night time.
If you put two panels in series they must be rated for the same current, because the panel with the least current will bring down the combined current to its level.
With flooded battery, you could simply connect it directly to the battery through a diode. The worst think that could've happen is some loss of electrolyte that is easily replenished. With sealed battery it's not a good idea to expose it to long periods of elevated voltage. So, you probably do need some sort of controller to limit voltage and to disconnect when it's fully charged. But you can make a really simple one. A mosfet which you turn on when battery voltage gets higher than your set point and off otherwise will work fine.