A charge controller connects your solar panels to your battery. It helps regulate the charging of you battery from the solar panels. I have had this charge controller for a couple of years and never had any issues. It is still going strong. I have used it to charge both Sealed AGM Battery and LiFePO4 batteries. Of course you would need to change the setting to match the corresponding charge profile. But the built in presets seemed to work fine for both.

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