The EcoFlow River 2 Max has 500W AC outlets, super fast 660W mains charging, two-way 100W USB power delivery output and charging input, and a 512 Wh long lasting LiFePO4 or LFP battery. It has a very useful app to control and monitor it remotely and it’s lightweight, especially considering its LFP battery. It’s pretty good value too, comparable to similar units – you can check the current price down below.
These power stations are perfect for power cuts, camping, travel and festivals and around the house and out and about to charge all your tech. And the River 2 Max can charge at up to 220W off solar panels alone when mains isn’t available.
I’ll run through its capabilities and thoroughly test all its claims to help you decide if this is the right power station for you. So let’s take a closer look.
Overview
In the box you get the power station itself, a mains charging cable, a car charging cable, a DC5521 cable and a quick start guide.
The River 2 Max has a 512Wh LiFePO4 or LFP battery which supports 3000 complete charge cycles compared to the 500 cycles of the River Max’s standard Li-ion battery. This is the smallest unit I’ve reviewed so far that comes with this more desirable battery chemistry.
It has a clean design but doesn’t feel quite as premium as other EcoFlow units I’ve tested. It’s made mostly from a hard plastic, but there is some movement and flex in some of its component parts. It is lighter than the original River Max though at 6.2kg – even more impressive considering it now has the LFP battery, and I much prefer its more useful flat top even it there’s a missed opportunity for a wireless charging pad or two. You can see its dimensions above, but although a little shorter than the River Max it’s a fair bit deeper, even before taking into consideration its rear carry handle. And it no longer has the removable battery of the original River Max.
The front of the unit has the now standard EcoFlow LCD screen but with just a single colour white display – not EcoFlow’s typical blue secondary colour.
Beside the display are 3 bog standard 2.4A USB-A ports – surprisingly none of these ports support any fast charging standards like Qualcomm Quick Charge. But there is a single two way USB-C 100W port both to fast charge your tech and also to charge the unit itself. On the other side of the display is the 12V 10A car charger outlet with a protective rubber flap and 2 3A DC5521 ports.
Below this UK version has two 500W AC outlets that can surge to 1000W. These outlets are well spaced and can accommodate even oversized plugs. The US version has 4 outlets – two 3 prong grounded and two 2 prong ungrounded outlets.
Press the power button to turn the unit on which also enables the USB ports. The DC and AC ports have their own power button.
Around the back of the unit is the mains charging port and the XT60 DC charging port for connecting to a car outlet or solar panels. There’s no flap covering these two ports which is unusual, but then like every power station I’ve tested the River 2 Max doesn’t come with any weatherproof rating, so you’ll need to take care using it outside anyway.
Charging
You can charge the unit with the mains cable, from a car outlet with the supplied car charging cable, via solar with optional solar panels and it supports charging at up to 100W using the two way USB-C port. It’s the first EcoFlow unit I’ve tested with this feature which can be very useful when there’s no mains or solar available.
Using the supplied standard 10A IEC mains cable – often called a kettle lead in the UK, the unit can charge at up to an impressive 660W. I didn’t quite see 660W, but charging at 600W I charged the unit’s 512Wh battery from completely flat to 80% charge in just over 40 minutes and a full charge took just under 1 hour and 3 minutes. EcoFlow quotes 1 hour for a full charge – so that’s close enough.
Charging at full speed the cooling fans turn on and are fairly noisy – I measured 46db with a sound level meter one metre away – that was around 10db louder than background noise in my office. But you can configure the charging speed from the full 660W down to 100W in 50W increments in the accompanying EcoFlow app. It will depend on the ambient temperature but generally the fans come on less at lower charging speeds, but they still run at the same speed and aren’t any quieter.
It is probably a little better for the battery charging at lower speeds, if you’re not in any rush.
I did check the River 2 Max’s temperatures when fast charging with a Flir thermal imaging camera and the design of the unit and the fans did a good job of keeping it cool as you can see.
The LCD display on the River 2 Max is bright and clear, and shows information on remaining charge time when it’s charging and remaining run time when it’s powering your devices.
This estimate is adjusted in real time depending on input or output power. There’s also the battery capacity displayed graphically and as a percentage and icons that illuminate to show which ports are in use. This information is also available in the app which can monitor the power station even away from home on a cellular connection if you connect to the device over WiFi.
There is also an option to connect directly to the power station over Bluetooth when there’s no WiFi – just tap on “use without Internet” when you’re asked to select your WiFi network. I’ve already covered adjusting AC charging speed under Settings in the app, and will mention other relevant options as I proceed through the review. I’d recommend making sure the firmware is up to date – there’s already been several updates to the firmware just whilst I’ve been testing the power station. The display is very clear indoors but a little harder to see outdoors in bright sunlight.
The unit charges at just under 100W with the supplied cable via a 12V car outlet. So a full charge would take around 6 hours. You also charge faster if your car has a 24V output, which I confirmed with my bench power supply charging the unit at just under 190W.
You are limited to 8A as you can see even with the bench supply set at 10A – this is set in the app and can’t be increased, only lowered. You need to manually select Car Recharging in DC mode in the app to get this to work.
If you manually select Solar Recharging in the app the unit will accept a voltage from 11V to 50V with a maximum or 13A but this can’t exceed 220W so the current starts dropping as the voltage exceeds 17V.
Like all the power stations I’ve tested the River 2 Max has a built-in MPPT controller for more efficient solar charging.
I tested solar charging with EcoFlow’s 220W bifacial solar panel which I discussed in my review of the more powerful EcoFlow Delta 2. It’s a good match for the River 2 Max’s maximum 220W solar input although it is quite pricey. But you can use pretty much any solar panel with the River 2 Max.
It’s winter here in the UK but I did manage to get one day in the last month of testing where the sun came out for enough time to test solar charging. You’ll need a MC4 to XT60 cable which isn’t supplied but is fairly easy to come by. Midday towards the end of January I got a maximum of 190W off the 220W panel which is pretty good. With the generous 11-50V input range of the power station, you could connect two panels in series and easily achieve the 220W maximum input even if you had a couple of smaller panels. As I’ve shown in previous power station reviews, it’s very easy to connect panels in series. These 220W panels are 21.8V – so two in series would be 43.6V which is still comfortably within the maximum 50V input of the River 2 Max.
Even at 180-190W the River 2 Max could be fully charged in a minimum of 3 hours.
Finally I tested the USB-C charging using the 100W output from my EcoFlow Delta 2. You do need to make sure you use a 100W rated cable with an E-marker chip, which isn’t supplied. I did get the full 100W, which will fully charge the power station in around 6 hours.
Performance
This UK version has two 500W AC outlets that can surge briefly to 1000W. I confirmed their sine wave output, which is important for sensitive electronics, with a graphical multimeter.
You can use EcoFlow’s X-Boost technology to continuously power devices rated at up to 1000W by lowering their voltage. So I can run this heater in its low 1000W mode – double the true rated output of the River 2 Max. But the voltage drops from around 240V UK mains voltage to under 170V.
The heater goes from drawing just over 1000W to just over 500W and this runs continuously, albeit for less than an hour. But at this lower voltage and output it’s barely generating any heat so isn’t particularly useful. X-Boost can be useful, but some devices may be sensitive to their voltage requirements and I’d recommend turning this feature off in the app and only enabling it for certain devices, like those with heating elements, when you’ve no other options. I’d like to see an X-Boost button on the unit itself to easily switch this feature on and off.
500W is still plenty to charge portable speakers, drones and laptops and run TVs, mini fridges, slow cookers and even some smaller power tools. To test it at its limits I tried running a few handheld power tools. This Festool 310W sander briefly draws over 800W at start-up but still didn’t trip the power station. And this slightly more powerful 400W Festool Rotex sander hovered comfortably around 500W.
I could just run this Ryobi 750W SDS drill if I ramped it up to full speed slowly, but this Bosch 720W angle grinder without any soft start instantly tripped the power station.
You should have some idea of what you’re plugging into the power station, but if you do exceed its 500W limit, overload protection kicks in and you’ll need to unplug the device and wait a few seconds before turning the AC subsystem on again.
The cooling fans will kick in intermittently at the same noise levels as when charging, depending on what you have plugged in.
It’s worth remembering to turn off the AC when you’re not using it. I measured between a 2-3% drop in capacity per hour just having the AC turned on with nothing plugged in. You can adjust the AC timeout in the app from 30 minutes to 24 hours or you can turn off the timeout completely. But unless you’re topping the unit up with solar you may well come back to an empty power station in a day or two.
I tested the DC outputs starting with the 12V car outlet which has up to 10A output at 12.6V or 126W, which I confirmed with a load tester. Ramping this up to 12A set off the current overload protection.
Using the same load tester I confirmed the 3A maximum output of the 12.6V DC5521 ports. You can’t set a timeout for the DC outputs in the app, but even if you leave them on they consume barely any power. These DC outlets are useful for camping accessories amongst other things. All these DC outputs are regulated.
There are 3 standard 5V 2.4A USB-A ports. It’s surprising these ports don’t support any fast charging standards but I confirmed their rated output with a USB load tester. There’s a far more useful 100W USB-C output.
The portable jump starter above can charge at the full 100W.
But more typically it’ll fast charge most laptops that support charging over USB power delivery, like most MacBooks and the Lenovo Chromebook in the photo above.
There’s no power button for the USB ports – it comes on with the unit which I prefer. And you can set the unit time out in the app to “never” to keep the USB ports on even when supplying tiny amounts of power, just like a mains wall charger.
The River 2 Max also has a UPS or uninterruptible power supply function. When the power station is charging off mains, any mains devices you plug in will bypass the power station and run directly off mains until there’s a power cut, when they’ll switch across to the power station’s battery. EcoFlow quotes a 30 ms switchover which I found good enough for a desktop computer for example, but they warn against using this feature for data servers that might require 0 ms switching. I’ve used this function before for running a 3D printer. It’s reassuring knowing that even a brief power outage won’t ruin a long print.
All ports support passthrough charging and can be used whilst the unit is charging. And all the ports can be used simultaneously.
Finally I measured the usable capacity of the 512Wh built-in battery. I ran two 100W incandescent bulbs at just under 200W until the power station turned off. They ran for 2 hours 19 minutes and consumed 439Wh according to the energy monitoring plug. Power stations like this will always have conversion losses and anything over 80% is pretty good. The EcoFlow works out at 439 Wh / 512 Wh which is around 86% and a good result. I did initially run this test at just under 500W and got 391Wh or just 76% efficiency. So the inverter does lose some efficiency as you run it closer to its maximum output probably due to heat loss.
I did a similar test using the DC output with a 10A electronic load attached. I measured 431 Wh which is a respectable 84% efficiency. But the DC output is more efficient running something like a camping fridge which turns on and off regularly, since there’ll be very little parasitic draw from the DC subsystem itself.
Conclusions
I’ve tested several EcoFlow units and they all offer a good feature set and performance at a fair price. At £550 or $500 the River 2 Max is not cheap, but with its LFP battery, super fast charging and 5 year guarantee it should definitely be on your shortlist if you’re after a 500W power station. Whilst you don’t need an app for a power station, remote control and monitoring via the EcoFlow app is surprisingly useful and also makes firmware updates, which often include new features, very easy. I like the USB-C charging option too and the unit is pretty light considering its long-life, usually heavier, LFP battery chemistry.
The build isn’t quite as good as EcoFlow’s more expensive units or the 1st generation River Max for that matter, and I would have liked all the USB ports to support fast charging.
The River 2 Max also loses the removable battery option the older River Max had. But that did make the River Max quite heavy even with its standard Li-ion battery and the internal battery still wasn’t replaceable.
I will be taking a look at the EcoFlow Power Kit soon to add power to my campervan. This system is entirely modular, but a fair bit more expensive. There’ll be a link on screen if that video is already out. I’m looking forward to taking a look at that system, but it’d be nice to see something modular at this price point with replaceable and upgradable batteries and other power station components like the inverter for example.
I’ ‘ve already reviewed power stations from Jackery, Bluetti and Allpowers that all come with similar outputs. Although those power stations all use standard Li-ion batteries with their associated shorter life.
I’ve got many more power station reviews in the works, so don’t forget to take a look at my YouTube video at the top of the page, and subscribe to my YouTube channel where I’m releasing videos every week on the latest technology and how to get the most out of it. If you tap the bell icon when you subscribe you’ll get a notification as soon as I release a video, and there’ll be a link to my site here for the written article. YouTube is also the best place to leave a comment. I read all of them and respond to as many as I can!
Purchase directly from EcoFlow: https://uk.ecoflow.com/products/river-2-max-portable-power-station
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EcoFlow River 2 Max: https://amzn.to/3JYMRF1
EcoFlow 220W Bifacial Solar Panel: https://amzn.to/3XkBUki
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