Redodo 12V 40A DC to DC Charger with MPPT
$279
Key Specs
| output-current | 40A |
| input-voltage | 9-16V |
| battery-chemistry-support | LiFePO4, AGM, Gel, Flooded |
| solar-input | Yes — MPPT |
| weight | 2.5 lbs |
| warranty | 2 years |
Pros
- ✓ Integrated MPPT solar input eliminates a separate solar charge controller
- ✓ 40A DC-DC output with proper multi-stage algorithm for LiFePO4
- ✓ Value pricing compared to Renogy and Victron combo units
- ✓ Smart alternator detection prevents parasitic start battery drain
Cons
- ✗ Redodo is a newer brand with shorter market history than Renogy or Victron
- ✗ MPPT solar input wattage ceiling is lower than Renogy's comparable unit
Detailed Review
Overview
Redodo has made a name in the budget-conscious LiFePO4 battery segment and brings that same value-first approach to their 12V 40A DC-DC Charger with MPPT. Like other combo units in this category, it merges alternator-based DC-DC charging with a solar MPPT controller under one roof, simplifying wiring and reducing the number of independent devices in your electrical system.
The 40A DC-DC output provides meaningful charge recovery while driving. For a 100Ah LiFePO4 bank at 50% state of charge, the charger can fully recover the deficit in about two hours of highway driving under ideal conditions. For a 200Ah bank, expect four to five hours — plenty for a long travel day between campgrounds.
Multi-Stage Charging and Alternator Protection
The Redodo uses a proper three-stage charge profile. In bulk stage, it delivers full 40A current to the battery. As battery voltage approaches the absorption setpoint, it holds that voltage while current naturally tapers. Finally, it drops to float voltage for maintenance charging. This profile is critical for LiFePO4 batteries: the cells need to reach a defined absorption voltage and hold it for a period before being considered fully charged. Dropping to float too early leaves capacity on the table.
The 40A current limit is equally important for alternator protection. A fully depleted LiFePO4 bank can pull hundreds of amps from an unprotected alternator circuit, causing overheating and premature failure. The DC-DC charger caps the demand at 40A, ensuring the alternator operates within its design parameters even when the house battery bank is deeply discharged.
MPPT Solar Charging
The integrated MPPT controller handles rooftop solar panels, extracting maximum energy through continuous power point tracking. When the vehicle is parked with panels in sunlight, the MPPT side maintains house battery charge without any contribution from the alternator circuit. When driving, the DC-DC side handles charging. The unit manages the transition between sources automatically.
Who It’s For
The Redodo 40A MPPT combo is a strong choice for budget-conscious RV and van builders who want dual-source charging without the cost of separate devices. Redodo’s two-year warranty provides reasonable coverage, and the product is well suited to weekend and seasonal use where the premium build of Victron or the brand recognition of Renogy matter less than the price tag.
