You can. The solar panel or solar array and the battery do not communicate. If left unchecked, the solar panel will continue to feed energy to the battery until the battery stops functioning, explodes, or potentially catches fire. You might think connecting a solar panel directly to a solar battery is okay. After all, solar panels and batteries both use DC voltage. However, when you connect the solar panel to the solar. The solution to prevent solar panels from overcharging solar batteries is a solar controller. These in-line devices are sometimes called solar. You would choose between a PWM or an MPPT controller for larger arrays. Both are acceptable and do a fine job of protecting the battery. However, the MPPT controller is more sophisticated, and. Suppose you are excited that there is an easy solution to keeping solar panels from overcharging batteries. In that case, you might be surprised to find out that there are different types of solar.