RV Converter/Charger Explained: What It Does and What to Buy
When you plug into shore power at a campground or a friend's house, a converter/charger is what turns that 120V AC into 12V DC to refill your house battery. Here's how to pick the right one.
For the full shore power setup, see charging systems guide and RV shore power setup.
Converter vs charger vs inverter/charger
Converter/charger: Shore power (120V AC) → house battery (12V DC). One direction only. This is what this article covers.
Inverter: House battery (12V DC) → appliances (120V AC). The opposite direction.
Inverter/charger: Does both — converts DC to AC when off-grid, and converts AC to DC (charges the battery) when on shore power. Examples: Victron MultiPlus, Renogy 2000W Inverter/Charger.
If you're building a van with a separate inverter and want shore power charging as well, you need a converter/charger. If you want to combine both in one box, get an inverter/charger.
What to look for
Output amperage: More amps = faster battery charging. 20–30A for a 100Ah bank; 40–60A for 200Ah+.
LiFePO4 charge profile: Must have a selectable LiFePO4 mode (14.6V absorption, 13.6V float). Units without LiFePO4 profiles will undercharge or stress lithium batteries.
Efficiency and heat: Better units are 90%+ efficient. A 30A charger at 14.4V output delivers 432W to the battery — if efficiency is 90%, it draws about 480W from the shore outlet.
Build quality: Units used in vans see vibration, temperature swings, and humidity. Marine-grade or automotive-rated chargers hold up better than cheap units designed for stationary use.
Best converter/chargers for van and RV builds
Victron Blue Smart IP22 12/30 — Best overall
Price: ~$215 | Output: 30A | LiFePO4: Yes | Bluetooth: Yes
The Victron Blue Smart IP22 is the default choice for van builds. It has a proper LiFePO4 charge algorithm, connects to VictronConnect via Bluetooth so you can monitor charging from your phone, and Victron's reliability is industry-leading. IP22 means it's splash-proof — fine for a van install.
The 30A output refills a 200Ah LiFePO4 bank in about 6–7 hours on shore power (accounting for absorption phase). For faster charging on a larger bank, step up to the Blue Smart IP22 12/30 or consider the Blue Smart IP67 12/25 (waterproof, marine-grade, ~$200).
PowerMax PM4-55A — Best budget high-output
Price: ~$180 | Output: 55A | LiFePO4: Selectable
The PowerMax is an American-made converter/charger with a strong following in the RV community. 55A output charges large banks quickly. It lacks Bluetooth monitoring, but it's robust, well-supported, and significantly cheaper than the Victron equivalent at this amperage. Has an equalization mode — make sure to disable it for LiFePO4.
Renogy 40A DC Home Charger
Price: ~$150 | Output: 40A | LiFePO4: Yes
Renogy's standalone shore charger is a solid budget option. LiFePO4 mode selectable, reasonable build quality. No Bluetooth, but functional and affordable.
Victron Blue Smart IP67 12/25
Price: ~$200 | Output: 25A | LiFePO4: Yes | Bluetooth: Yes | Waterproof: IP67
The IP67 variant is fully waterproof — better for installs where moisture exposure is possible. Slightly lower output than the IP22 at similar price, but worth it for marine-influenced builds.
Wiring
The converter/charger sits between your shore power inlet and your house battery:
- Input: 120V AC from the shore power inlet (fused at the inlet)
- Output: 12V DC to the house battery positive and negative (fused within 12 inches of the battery)
The 120V input side should be protected by a 15A or 20A breaker. The DC output cable sizing depends on the charger's amp output — a 30A charger needs 10 AWG cable for runs under 10 feet.