How To Keep A Solar Panel From Overcharging A Battery

The solar power generated by the solar panel is received by the solar charge controller.

How to keep a solar panel from overcharging a battery.

A solar controller with a battery temp sensor and adjustable setpoints will eventually pay for itself in battery life especially if one charges in areas with wild temperature extremes. A cheap pwm controller will do this ok though they are less efficient for the charging process. A solar charge controller is a component that helps manage the power that is going into the battery store from the solar panel. As peter said you can overcharge a battery if you don t have a solar controller between the solar panel and the battery.

I ve spent the winter designing a pwm solar charge controller which is now finished and working. Here i m using it to charge a 12 volt car battery as quickly as possible without overcharging. If you want to get more efficient charge for your solar power you can use one of the many solar fed switch mode battery charger chips like the ti bq24650 this also gives you more flexibility for use of lifepo4 which is starting to replace lead acid. Even a small solar panel hooked directly to a fully charged battery can overcharge it.

Connect the wires from the controller to the solar panel. Match up the male and female connectors with the opposite ones coming away from the solar panel and snap the mc4 connectors into place. Using a solar controller limits the charging voltage to a safe 14 5v or so and protects the battery.