Description
The DELTA 3 Smart Extra Battery is a 1024 Wh extra battery that connects to a station you already have and increases the energy reserve without buying a new one. According to EcoFlow’s official compatibility table it works with the EcoFlow DELTA 3, DELTA 3 Plus, EcoFlow DELTA 3 1500 and EcoFlow DELTA 2, and the EcoFlow DELTA 3 Max Plus page also names it among compatible batteries. If you are planning to buy an EcoFlow DELTA 3 Smart Extra Battery for your DELTA 3, the simplest result is this: the capacity doubles to 2048 Wh.
During scheduled outages in Ukraine the difference is felt immediately: the fridge, router and boiler last twice as long, and you use the window of mains power to charge the whole system. The battery has no outlets of its own; it works only paired with a station.
What an expansion battery is for
Twice the energy for DELTA 3
DELTA 3 itself has 1024 Wh. With the battery you get 2048 Wh, so the station gets through a typical evening and night without power without strict economy. For DELTA 3 1500 the total capacity grows from 1536 to 2560 Wh.
4000-cycle lifespan
Inside are LiFePO4 cells that, according to EcoFlow, keep over 80% capacity after 4000 cycles. For a battery used daily that is about 10 years.
9.6 kg and the same base size
The battery measures 398 × 200 × 198 mm, that is, the same base as DELTA 3. It can be placed on top of the station, and together they take up the floor space of one station.
No separate setup
After connection the station itself shows a battery icon on its display, and both devices switch on and off together. The state of the extra unit is visible in the EcoFlow app.
Compatibility
One such battery connects directly to each of these stations. The data is taken from EcoFlow’s official compatibility table and from the stations’ pages.
| Station | Own capacity | With battery |
|---|---|---|
| DELTA 3, DELTA 3 Plus | 1024 Wh | 2048 Wh |
| DELTA 3 1500 | 1536 Wh | 2560 Wh |
| DELTA 2 | 1024 Wh | 2048 Wh |
| DELTA 3 Max Plus | 2048 Wh | 3072 Wh |
It does not fit DELTA 3 Classic and DELTA 3 Max: these models have no extra battery port. DELTA 2 Max and the DELTA Pro series stations are not listed in the compatibility table either.
The battery connects to the station’s XT150 port with a DELTA 3 Extra Battery Cable, which, per EcoFlow’s manual, is included. The manufacturer recommends placing the battery on top only on DELTA 3 and DELTA 3 Plus, and with other stations it is better to place it alongside.
How much run time the battery adds
At the 230 V outlets about 870 Wh of the 1024 Wh actually arrives, because the station’s inverter takes part of the energy. That is how much the battery adds. Below is the approximate gain for individual appliances; the real result depends on equipment and temperature.
- fridge (1–1.5 kWh per day): plus 14–20 hours;
- gas boiler with a circulation pump (100–150 W): plus 6–9 hours;
- laptop, monitor and router (about 120 W): plus 7 hours of operation;
- router with an optical terminal (15–25 W): plus 35–55 hours.
For an apartment this means a fridge, router and a few lamps together (150–200 W) run from DELTA 3 with the battery for roughly 8–11 hours instead of 4–6.
How to connect and use it
Switch the station off, connect the cable to the extra battery port on the station and to the XT150 port on the battery, then switch on either of the two devices. The manual forbids connecting or disconnecting the cable while the station is running. When the battery icon appears on the station’s display, the system is ready.
The battery has no separate charging input: it charges through the station from the mains, solar panels or a car, that is, from the sources your station supports. In the same way it can be charged from an EcoFlow Smart Generator through the XT150 port. Because of the larger energy reserve, a full charge of the system takes longer than for the station alone.
According to the manual, the battery backs the station up and powers the load when the station’s own battery runs down.
A battery or a more powerful station
The battery increases only the energy reserve. The output power remains that of the station: for DELTA 3 it is 1800 W, and a 2200 W kettle or boiler will not work any better because of it.
If you already have a DELTA 3, the battery is the simplest way to get 2 kWh. If you do not have a station yet and need both 2 kWh and 3000 W of power for kitchen appliances, consider the EcoFlow DELTA 3 Max Plus. For DELTA 3 1500 owners who need even more, EcoFlow also allows the 4096 Wh DELTA Pro 3 Smart Extra Battery.
Who it suits and who it does not
It suits you if:
- you have a DELTA 3, DELTA 3 1500 or DELTA 2 and the reserve is not enough for the night;
- you want to grow the capacity gradually rather than replace the station;
- it matters that the system takes up little space: the battery sits on top of DELTA 3.
It will not fit or makes no sense if:
- you have a DELTA 3 Classic, DELTA 3 Max or DELTA 2 Max — they do not support this battery;
- what you lack is not an energy reserve but power at the outlets;
- another extra battery is already connected to the station: there is one port for it.
FAQ
Can two of these batteries be connected to DELTA 3?
No, DELTA 3 has one extra battery port. If you need more than 2 kWh, a 4096 Wh DELTA Pro 3 Smart Extra Battery can be connected to it instead of this battery, and then the system reaches about 5 kWh.
Can the battery be used separately from the station?
No, it has no outlets or USB. It is only an energy reserve that the station uses through its inverter and its ports.
Does the battery fit DELTA 2?
Yes, DELTA 2 is in the official compatibility table. DELTA 2 also has its own DELTA 2 expansion battery of the same capacity.
How do I charge the battery from the sun?
Through the station. Solar panels connect to the station’s solar input, and the station itself distributes energy between its own battery and the extra battery. The battery has no separate solar input.
Can the battery be left unused for months?
Yes, but once every three months it should be discharged to zero, fully charged and discharged again to about 60%. It is better stored at 20–30 °C and charged only at a temperature from 0 °C.
Does the battery speed up the station’s charging?
No, the charging speed is determined by the station’s input. On the contrary, because of the doubled capacity, fully charging the system takes roughly twice as long.
Summary
The DELTA 3 Smart Extra Battery is the most direct way to double the energy reserve of a DELTA 3 or to add a kilowatt-hour to a DELTA 3 1500 and DELTA 2. For those who have already decided to buy an EcoFlow DELTA 3 Smart Extra Battery, it is enough to add it to the cart above. If you doubt compatibility with your station, write to us through the contacts and we will advise.
