This small box provides the power needed when off the grid

EcoFlow’s Alternator Charger is an accessory that you install in your truck, van, or RV to charge the main power station you carry to keep all your gear running.

While your car is on, the Alternator Charger produces up to 800W. That’s eight times more power than you can get from a 12V cigarette lighter socket, and enough to charge the new 1kWh Delta 3 EcoFlow from zero to full in just over one hour of driving. It takes five hours when you go with EcoFlow’s 4kWh Delta Pro 3.

It’s also smart enough to reverse the flow of electrons, using a power channel to keep your starter battery on a buzzing charge or skip to bring it back to life. When you’re coming home from work or vacation, those big-ass portable batteries can be plugged into a $200 EcoFlow balcony solar kit to help pay your energy bill and provide emergency power during a power outage.

The EcoFlow Alternator Charger is far from an industry first, and uses proprietary connectors that only work with Ecoflow batteries. But the company brings simplicity, beauty, and a better user experience to a product that is often designed for electricians and mechanics.

After 3,700 miles (6,000km) of testing, I can say that the $599 Alternator Charger may be a game changer for many. It has allowed my wife and I to live and work comfortably from a Sprinter van this summer, comforted by all the modern conveniences of on-demand power.

It is common for RV builders to install aftermarket DC-to-DC chargers in the vehicle’s alternator. They are incredibly good at keeping battery stacks charged for off-grid conveniences like e-bikes, projectors, 3-in-1 refrigerators with ice makers, coffee makers, and air conditioners. Some basic chargers are less expensive and some are more powerful than EcoFlow, especially when built around a secondary alternator — but those offer fewer features and require professional installation.

To avoid overloading the car’s alternator, the EcoFlow charger self-regulates itself to finish the remainder power, which can be less than 800W, is sent to the power station. (Alternator charger can draw a maximum of 76 amps.) In my case, the Sprinter’s beefy alternator has enough power to easily deliver 800W almost continuously even with the A/C running and the wipers and lights on.

I also went with 420W of solar panels mounted on the roof for an extra boost, resulting in a real-world charge of just over 1,100W at a time when driving on sunny days. This combo also works while the van is stationary and idling if I ever need the Sprinter to act as an emergency diesel generator.

An EcoFlow installation qualifies as a DIY project for many The Verge readers, although in my case I turned to an expert for help: Fabian van Doelaar, who had already modified my cargo van with Solo interiors and helped me previously with my review of the EcoFlow Power Kit.

EcoFlow offers a couple of helpful videos showing an Alternator Charger installed in a Ford F150 pickup and another showing it installed in an older Sprinter based RV.

Installing the Alternator Charger requires wiring it back to the starter battery, not the alternator itself. The exact steps for each car will be different, but in the case of my Sprinter, we ran a 16 meter (five meter) thick cable up the bus bar to the auxiliary battery fuse box, which meant removing the driver’s seat. The cable was long enough to reach the Alternator Charger box that is installed inside the cabinet in the back where I carry my power.

My Sprinter van was designed from the ground up to be powered by any portable solar generator, which is just a large power station that includes an MPPT charge controller for the solar panels. For this review, we connected my van circuit to the original Delta Pro EcoFlow which was also connected to the Alternator Charger using the proprietary EcoFlow cable and adapter.

The Delta Pro keeps my laptops, phones, drones, and headphones charged, in addition to powering my Starlink Internet, lights, refrigerator, water pump, induction cooktop, and roof vent, and EcoFlow’s Wave 2 air conditioner and heater combo I recently made. updated. So having a reliable way to charge was important this summer as I wanted to live and work remotely as much as possible.

After the direct installation, it was time to set up the Alternator Charger in the excellent EcoFlow app, which makes performance monitoring fun and addictive.

The Alternator Charger only sends power to the power station after two conditions are met. First, the charger must be turned on with a button on the unit itself or from the “start to work” switch in the EcoFlow app. Then, the voltage measured on the starter battery must exceed the “start voltage” limit you set in the EcoFlow operating system. When left, it should charge the attached power station while driving – but that didn’t work well in my setup.

I first went with an initial application voltage of 13.0V. Starting the van causes the starter battery voltage to jump from about 12.6V – 12.8V to over 14V, thus triggering an 800W charging session. But my van is equipped with a smart alternator that causes the voltage to fluctuate over time, sometimes dipping below that 13.0V limit. This causes the Alternator Charger to cycle off and on repeatedly, thus slowing down the speed at which the Delta Pro charges.

To “fix” this, I lowered the starting voltage of the charger to 12.5V (limited to 0.5V adjustment) in the application with a potentially predictable result — when I arrived and turned off the engine, the Alternator Charger started draining my van’s battery again. it would have continued to do so until it reached the 12.5V threshold and stopped.

That’s not the end of the world, but it’s below the 12.6V resting limit that’s considered healthy for a lead-acid starter battery. EcoFlow makes it easy to manually transfer stored power from the Delta Pro battery back to the Sprinter by switching the Alternator Charger to Reverse Charge or 100W Battery Storage modes — but this is not ideal.

Ideally, all this will work automatically, so that every time I drive I know that 800W is being returned to my power station, and I don’t have to worry about the life of my first battery after parking. Lacking those guarantees, I decided to play it safe, and leave the starting voltage at 12.5V but change the “start” button in the operating system manually every time I start and stop driving.

Still, after testing EcoFlow’s Alternator Charger, I can tell you that $599 is a small price to pay for the peace of mind of having all that power available whenever I need it for two months this summer—rain or shine, even in the middle of nowhere. somewhere. Shame it has to be turned on and off manually for me, and it only works with EcoFlow batteries.

EcoFlow products are often available on sale year-round with discounts available in bundles. The $848 bundle that includes the Alternator Charger and the new $649 Delta 3 Plus looks like a great deal for a 1kWh solar generator that can grow with your needs.

All photos by Thomas Ricker / The Verge