Sunsei SE-1500 22.5-Watt 15-Volt Solar Panel Battery Charger 25015 22.5-Watt (1500mA, 15-Volt) solar charger for battery charge and protection against battery drain Can also be used for charging small backup power systems Plug-n-play to easily connect multiple panels in seconds without tools or rewiring Suggest you also purchase a 10-Amplifier charger controller to protect against overcharging Includes multiple adapters and connectors