How RV Battery Charging Works

Understanding the converter/charger that replenishes house batteries from shore power, solar, or generator sources.

Your converter/charger is the unsung hero that keeps your 12V system alive. It takes 120V AC power and turns it into the 12V DC your batteries need.

Multi-Stage Charging

Smart chargers use three stages: Bulk (fast charge to 80%), Absorption (slower topping off), and Float (maintenance). This protects batteries from boiling over while ensuring a full charge.

Converter vs. Inverter

Don't confuse them! Converter: 120V AC -> 12V DC (charges battery). Inverter: 12V DC -> 120V AC (uses battery). Most RVs have a converter; upgraded ones have both or a combined unit.

Charging from Tow Vehicle

Your 7-way plug provides a 'trickle charge' from the tow vehicle's alternator while driving. It's usually not enough to recharge a dead battery but maintains the charge level during travel.

Important Notes

  • Check battery water levels monthly (for lead-acid types)
  • Lithium batteries require a specific charging profile/converter
  • Corroded terminals prevent proper charging—keep them clean

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