12V Lead Acid Battery Charger 3A DC-DC Solar Panel MPPT Control 17V-28V In

Connect the 12V (18Vmp) solar panel to the inputs. Connect the battery first, then the solar panel. Connect the output directly to lead-acid battery. Looking at the photos, you can see for 8.2W being generated, it put 7.8W into the battery, giving a decent 95% efficiency.

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