EcoFlow RIVER 2 Max 500 with the EcoFlow NextGen 220W Bifacial
Works with the right cable · 2S1P · 220 W
This port needs an MC4 to XT60i cable with the signal pin. Owners report a plain 2-pin XT60 limits solar input to about 8 A.
Thick mark: cold Voc · Thin mark: operating Vmp, 36.8 V
3 caveats
- Only 1.0 V of margin below the 50 V limit at -10 °C, and a colder morning could breach it. Use fewer panels in series if your winters are colder.
- The maker publishes no temperature coefficient, so cold voltage uses our conservative −0.40 %/°C.
- The connector type comes from a secondary source, so check the physical port.
Parts for this layout
- EcoFlow RIVER 2 Max 500$329 View on Amazon
- 2 × EcoFlow NextGen 220W Bifacial$798 View on Amazon
- 10AWG Solar to XT60i Cable XT60i to Solar Connector Adapter Cord$13.99 View on Amazon
Estimated total $1,140.99
Prices can change. The price on Amazon at purchase is what applies.
Can I connect the EcoFlow NextGen 220W Bifacial to the EcoFlow RIVER 2 Max 500?
Yes, with limits. The best setup is 2 panels wired 2S1P on Solar Input, delivering up to 220 W. That string reaches 49.0 V at −10 °C against the port’s 50 V limit, using our cautious cold-weather assumption because EcoFlow publishes no temperature coefficient. Check your own unit’s labels too.
Danger: overvoltage risk. Do not connect the layouts marked red below. Going over a station’s input voltage limit can permanently damage it.
What is the best way to wire EcoFlow NextGen 220W Bifacial panels to the EcoFlow RIVER 2 Max 500?
Wire them 2S1P on Solar Input for about 220 W from 2 panels. The string runs at 36.8 V, above the 11 V minimum the port needs to start. Stop at 2 in series on the lowest-voltage port, because 3 in series exceeds its limit in the cold.
| Port | Layout | Voc 25 °C | Voc 0 °C | Voc −10 °C | Voc −20 °C | Vmp | Isc | Watts | Verdict at −10 °C |
|---|---|---|---|---|---|---|---|---|---|
| Solar Input | 1S1P | 21.5 | 23.7 | 24.5 | 25.4 | 18.4 | 12.4 | 219 | Works with the right cable |
| Solar Input | 1S2P | 21.5 | 23.7 | 24.5 | 25.4 | 18.4 | 24.8 | 220 | Over the current limit |
| Solar Input | 2S1P | 43.0 | 47.3 | 49.0 | 50.7 | 36.8 | 12.4 | 220 | Works with the right cable |
| Solar Input | 2S2P | 43.0 | 47.3 | 49.0 | 50.7 | 36.8 | 24.8 | 220 | Over the current limit |
| Solar Input | 3S1P | 64.5 | 71.0 | 73.5 | 76.1 | 55.2 | 12.4 | 0 | Danger: overvoltage |
| Solar Input | 4S1P | 86.0 | 94.6 | 98.0 | 101.5 | 73.6 | 12.4 | 0 | Danger: overvoltage |
How cold can it get before this string overvolts the EcoFlow RIVER 2 Max 500?
A string of 2 EcoFlow NextGen 220W Bifacial panels breaches the 50 V limit of Solar Input once cells fall below −16 °C. Voltage rises as cells cool, at our assumed −0.40 %/°C (no figure is published), so a clear winter sunrise is the worst case. Stay at 1 in series or fewer there.
The cold-weather correction is the same one NEC Article 690.7 requires for PV system voltage.
Which cable connects the EcoFlow NextGen 220W Bifacial to the EcoFlow RIVER 2 Max 500?
You need an MC4 to XT60i cable with the signal pin. Owners report that a plain 2-pin XT60 limits EcoFlow solar input to about 8 A, which would cap this string near 294 W. Keep runs short, because voltage drop grows with current and distance.
How long does the EcoFlow NextGen 220W Bifacial take to recharge the EcoFlow RIVER 2 Max 500?
Expect about 2.3 peak-sun hours for a full charge from 2 panels. That’s 0.4 days in Denver, CO in June and 0.5 days in December, using a 0.70 real-world derate and NREL irradiance data. Clouds, shade and panel angle can all push it longer.
| City | June | December |
|---|---|---|
| Phoenix, AZ | 0.3 | 0.4 |
| Denver, CO | 0.4 | 0.5 |
| Los Angeles, CA | 0.3 | 0.5 |
| Austin, TX | 0.4 | 0.5 |
| Miami, FL | 0.4 | 0.5 |
| Atlanta, GA | 0.4 | 0.6 |
| Chicago, IL | 0.4 | 0.9 |
| New York, NY | 0.4 | 0.8 |
| Seattle, WA | 0.5 | 1.4 |
Where do these EcoFlow RIVER 2 Max 500 and EcoFlow NextGen 220W Bifacial numbers come from?
Station limits come from us.ecoflow.com and panel ratings from us.ecoflow.com, each checked against a verbatim quote on that page. Panels must also pass a physics test: Vmp times Imp must land within 15% of rated watts. Anything failing goes to quarantine and gets no page.
| Rated power | 220 W | us.ecoflow.com“220W (±5W) Front/175W Rear” |
|---|---|---|
| Open-circuit voltage (Voc) | 21.5 V | us.ecoflow.com“21.5V (Vmp 18.4V)” |
| Operating voltage (Vmp) | 18.4 V | us.ecoflow.com“Vmp 18.4V” |
| Short-circuit current (Isc) | 12.4 A | us.ecoflow.com“12.4A (Imp 11.9A) Front Side” |
| Operating current (Imp) | 11.9 A | us.ecoflow.com“Imp 11.9A” |
| Voc temperature coefficient | −0.40 %/°C | Assumed: not published by the maker |
| Output connector | MC4 | us.ecoflow.comsecondary“Photovoltaic connectors (adapted to MC4 connectors)” |
| Solar Input | 11 to 50 V, 13 A, 220 W | us.ecoflow.com“11-50V, 13A, 220W Max” |
|---|---|---|
| Solar Input connector | XT60i | us.ecoflow.com“Works best with RIVER 2/RIVER 2 Max/RIVER 2 Pro” |
Prices last checked and spec data verified on .