They are usually wired in parallel to preserve the voltage of each panel but you can also wire sets of them together in series to increase the voltage to conform to the voltage of the battery bank if need be.
How do you wire a solar panel to a battery.
Divide the wattage of the solar panel by the voltage of the battery to get the number of amps your charge connector needs to handle.
Connect the positive wire from the solar panel to a battery cable with a fusible link between the battery and the solar panel.
Connect the negative wire of the solar panel to the negative terminal of the battery.
Step 1 connect the panels of a solar bank together if there are more than one.
The following solar panel wiring diagram shows that a 12v 120w pv panel is connected to the solar charge controller panel negative terminal of panel to the negative terminal of mppt charge controller and vice versa for positive terminal.
To wire two or more solar panels and batteries in parallel simply connect the positive terminal of solar panel or battery to the positive terminal of solar panel or battery and vise versa respectively as shown in the fig below.
As you see in the connection diagram at first the solar panel is connected to the solar charge controller and then a 24v battery is connected to the charge controller.
Solar panels are wired in series when you connect the positive terminal of one panel to the negative terminal of another.
An inverter is connected to the battery.
Then run wires from the battery to the charge connector making sure to match the positive and negative poles.
This will help prevent a fire or battery explosion in the event of a short in the wiring.