【 Ultra-Smart MPPT Technology 】This 24v solar panel battery charger is crafted with SUNER POWER's unique Ultra-Smart MPPT technology, the innovative MPPT ( Max Power Point Tracking) allows to deliver high tracking efficiency of up to 99% and peak conversion efficiency of 98%, improving approximately 20%-30% utilization rate than other competitors. 【Improved 3-stages Charging】The improved 3-Stages charging algorithm (Bulk, Absorption, Float) allows to charge 24-volt battery more effectively, ensures battery is safely recharged and increases battery life.The solar trickle charger stops charging when battery has full charge, and automatically resumes when battery has discharge, totally free maintenance. 【Full Safety Protections】Built-in multiple protections including over-charge, over-discharge, over-voltage, over-current, over-load, short circuit, reverse polarity, and over-temperature, waterproof and spark-proof, the battery is fully protected. 【 Three Battery Charging Modes 】Independently charge and control each 12 volt battery with selectable charging modes - including 24V, 24V AGM and 24V Lithium - for all types of lead-acid boat, car, dump trailer, automotive, marine, RV, powersport, camper and deep cycle batteries, including flooded, gel, AGM, SLA, VRLA and maintenance-free, plus lifepo4 lithium batteries. 【 Visual Charging Level】The charge level indicators allow to visually monitor the stage of charge among 25%-50%-75%-100%. It's not just a solar battery trickle charger, it's an advanced solar battery charger maintainer. A fully-automatic, worry-free smart solar battery charger with zero overcharge. 【 Wide Compatibility】It's not just a solar battery trickle charger, it's an advanced solar battery charger maintainer. A fully-automatic, worry-free smart solar battery charger for 24 volt sealed lead-acid car, automotive, marine, RV, powersport, boat, dump trailer, gate opener, fence and deep-cycle batteries, including flooded, gel, AGM, SLA and maintenance-free, plus lifepo4 lithium batteries. SUNER POWER 24V 20W Solar Battery Charger Maintainer, Built-in Ultra Smart MPPT Charge Controller, Waterproof 20 Watt Solar Panel Trickle Charging Kit for 24Volt AGM, Lead-Acid, Lifepo4 Battery