High-Efficiency Dual-Input Charger for Reliable On-Board Power

The Renogy 12V 40A DC-DC On-Board Battery Charger provides efficient and stable charging for auxiliary batteries from your vehicle’s alternator. Designed for RVs, boats, and off-grid vehicles, it ensures safe and optimised power transfer between the starter and auxiliary batteries. Featuring advanced multi-stage charging, wide battery compatibility, and multiple protection layers, it guarantees superior performance and battery health under demanding conditions.

Key Features

• High Conversion Efficiency: Achieves up to 94% efficiency, ensuring faster, cleaner energy transfer between batteries.
• Smart Alternator Compatibility: Automatically adapts to traditional or variable voltage alternators, ensuring consistent performance in modern vehicles.
• Versatile Battery Support: Compatible with sealed, gel, flooded, AGM, and lithium (LiFePO₄) batteries, including custom user-defined charging profiles.
• Advanced Multi-Stage Charging: Uses bulk, boost, float, and equalisation stages for complete, balanced charging cycles.
• Automatic Lithium Activation: Revives deeply discharged lithium batteries for dependable performance and extended lifespan.
• Comprehensive Protection: Built-in safeguards prevent damage from overvoltage, reverse polarity, overheating, and short circuits.
• Compact and Robust Design: Lightweight housing with natural convection cooling and IP32 ingress protection, ideal for on-road or marine installations.

Built to deliver dependable performance in all environments, this charger ensures your auxiliary batteries remain fully charged and ready, maximising power independence wherever you travel.