- 1). Connect the negative end (terminal) of one 12V battery to the positive end (terminal) of the second 12V battery using a battery cable.
You are connecting the batteries in a series, a process which doubles the voltage while keeping the capacity (amps hours) the same. If you connect the batteries in parallel (positive to positive and negative to negative), you will double the capacity, but keep the voltage constant. - 2). Connect a second battery cable to the positive terminal on the first battery.
- 3). Connect a third battery cable to the negative terminal on the second battery.
- 4). Connect the two loose cables to the appropriate negative and positive inputs in your solar panel or any other input device.
Most solar panel installation specialists recommend putting a charge controller between your batteries and the panel in order to protect both your panels and your batteries from changes in the flow of energy as the amount of sunlight and the power generation of your panels changes. If you choose to use a charge controller, connect the batteries to your charge controller and your charge controller to the solar panels.
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