The circuit design is extremely straightforward and may be understood with the following points.
Solar panel charger circuit design.
So batteries and the circuit dictate the solar cell size there are some of these lights with pr sensors that use a 3 7 volt battery and a solar cell of 4 5 volts.
Here lm317 can produce a voltage from 1 25 to 37 volts maximum and maximum current of 1 5 amps.
In this video how to 12v lead acid battery or any battery solar charger controller make with 25w 12v poly solar panel previous video 12v solar battery char.
The intersection of the v reg power line continues to follow up the solar panel s power curves until the charger exits constant current mode.
The diode d1 provides reverse polarity protection and capacitor c1 buffers voltage from the solar panel.
If a 20w solar panel has an output current of 2 5a in full sunlight the charge current will be 2 5a.
1 x 1 2 volt battery at least 1 5 volt solar cell in full sun.
In this circuit the solar panel charges up a 3 cell nimh battery 3 6 v.
1 x 3 7 volt battery at least 4 5 volt solar cell in.
You will need just a solar panel panel a selector switch and some diodes for getting a reasonably effective solar charger set up.
Op amp ic1 is used as a simple voltage comparator.
Between the two is a reverse blocking diode.
2 x 1 2 volt batteries at least 3 volt solar cell in full sun.
As can be seen in the given circuit diagram the design basically consists of a solar panel a pnp transistor few leds a battery and a few resistors.
The output current is identical to the solar panel output current.
The second design explains a cheap yet effective less than 1 cheap yet effective solar charger circuit which can be built even by a layman for harnessing efficient solar battery charging.
Solar battery charger circuit design circuit must have adjustable voltage regulator so variable voltage regulator lm317 is selected.
Hybrid solar charger circuit working.
This one way valve allows current to flow from the solar panel to the battery but does not allow current to flow backwards out of the battery through the solar panel.
In our case we connect the ve of the solar panel to the pole of the relay and ve of the battery to n o when the battery is connected to the scc solar charge controller the circuit check the battery voltage the voltage is less than or equal to lower limit the current is flows to the battery and battery start charging.
The circuit in action.
Regarding the battery ah capacity it is generally best if the battery can be fully charged within one day or less.