Anker SOLIX F3800 Plus vs EcoFlow DELTA Pro 3: which home backup battery should you buy?

Specs side by side

Specs as each maker states them.

The key differences at a glance

Anker lists 3,840 Wh and up to 6,000 W of AC output. EcoFlow lists 4,096 Wh and 4,000 W, or 6,000 W with X-Boost. Both use LFP cells, both give 120V and 240V, and both advertise a 5-year warranty. Anker lists up to 3,200 W of solar input against EcoFlow's 2,600 W. EcoFlow is the lighter unit at 113.54 lb, while Anker's manual gives 135.6 lb. Anker lists LFP with 3,000+ cycles, and EcoFlow rates its battery at 80% or more after 4,000 cycles. Our home backup battery guide shows where both sit among the other big units.

Output and 240V

Anker's manual lists 6,000 W in total: the L14-30R 120V/240V port at up to 6,000 W, the TT-30R 120V port at up to 3,000 W, and two groups of three NEMA 5-20R outlets at 2,400 W per group. EcoFlow's manual lists 4,000 W with an 8,000 W surge. EcoFlow's X-Boost reaches 6,000 W; the manual says it suits heating devices, does not support devices with voltage protection, and is unavailable while the unit charges from AC.

Plugged into a wall outlet, both change what they offer. Anker's page says the 240V output cannot be used while the unit charges through 120V AC, and its manual's FAQ says only the three 120V UPS outlets work then. The manual lists a UPS switching time of 20 ms. EcoFlow's manual lists its bypass-mode output as 100-120V at 4,000 W, and says its HV and LV AC output buttons cannot be used at the same time. Check this limit against your plan if you keep the unit plugged in as a UPS.

Charging, solar and generators

Anker lists two solar inputs, each 11V to 165V and 17A for up to 1,600 W, so 3,200 W in total; its manual warns that voltage over 165V will damage the product. AC charging is 1,800 W at most, and the manual's temperature table caps charging power at 760 W between 0 and 10°C (32 and 50°F). For a 240V generator, Anker's page lists a bypass of up to 6,000 W and says its Generator Adapter is required and supports a single F3800 Plus only. Through the adapter one F3800 Plus recharges at up to 3,300 W, or up to 6,000 W with expansion batteries connected, and Anker's adapter page says the NEMA 5-20R outlets are disabled while the adapter is connected. For a 120V generator, Anker's FAQ says to connect it to the F3800 Plus's Home Power Panel port and use the TT-30R output for up to 3,000 W, and that the generator must output 120V pure sine wave power with total harmonic distortion under 5%.

EcoFlow lists 2,600 W of solar across two ports, up to 1,600 W high-voltage (30V to 150V) and up to 1,000 W low-voltage (11V to 60V), so Anker leads on solar by 600 W. EcoFlow lists 0 to 80% in 50 minutes and up to 7,000 W of charging with multi-charge combinations, so check which inputs that assumes. On the US model, EcoFlow's FAQ says the grid port supports 120V charging at 2,000 W. For generators, EcoFlow's manual lists a generator on the AC input socket with the supplied cable, its Smart Generator on the extra battery port, or a split-phase generator port with its adapter. See our solar panel picks for pairing panels with either unit.

Expansion and connecting it to your home

Anker's manual says BP3800 expansion batteries raise one unit's capacity to as much as 26,880 Wh. Anker's pages list up to six of them at 3.84 kWh each, and up to 53.8 kWh for a dual system. A Double Power Hub joins two F3800 Plus units for up to 12,000 W, and each expansion battery is listed at 72.8 lb. EcoFlow's single unit takes up to two extra batteries, up to 12 kWh, at 33 kg each. Its range runs from 4 to 48 kWh, but the footnote puts the top figure on a three-unit setup with three extra batteries, three Smart Generator 4000 units and a Smart Home Panel 2.

Anker sells the F3800 Plus with a 10-circuit manual transfer switch, and a Smart Home Power Kit with a panel, subpanel, circuit breaker and ground bar; that kit's page says the Home Power Panel supports only 120/240V split-phase systems, not 120/208V. Anker says its Storm Guard starts charging automatically when the F3800 Plus and Home Power Panel are warned of extreme weather, and notes that it needs the Home Power Panel. Its manual says the neutral and ground wires of the inlet box or transfer switch must be properly connected. EcoFlow's Smart Home Panel 2 takes up to three DELTA Pro 3 units, with a 20 ms switch-over and app control of up to 12 circuits, and EcoFlow also lists an inlet box on the built-in L14-30R socket. EcoFlow's manual says a transfer switch is essential to isolate backup power from the grid. Read our generator safety guide on back-feeding before wiring either one.

Weight, size, battery life and warranty

Anker's manual gives the F3800 Plus as 61.5 kg (135.6 lb) and 27.6 by 15.3 by 15.6 in; its product page lists 136.7 lb. EcoFlow's manual gives 113.54 lb and 16.16 by 13.43 by 27.28 in. Anker's support site says the F3800 Plus is not waterproof. EcoFlow rates the main unit IP20 and the battery pack IP65, and says the unit suits well-ventilated indoor or sheltered outdoor spots. Anker lists discharging from -4°F to 104°F and charging from 32°F to 104°F; EcoFlow lists discharging from 14°F to 113°F and charging from 32°F to 113°F. Anker's pages give no noise figure that we found, and EcoFlow quotes noise as low as 30 dB.

Both advertise 5 years. Anker's page pairs its 5-year warranty with a lifespan of 10 years or more. EcoFlow's 5 years is 3 standard plus 2 after you register in the EcoFlow app, and its manual voids the warranty if the unit is left uncharged or unused for more than 6 months. On cycles, Anker's F3800 Plus page lists LFP with 3,000+ cycles and no end-of-life capacity; its Smart Home Power Kit page lists 3,000 cycles at at least 80% battery capacity, in a table headed F3800 rather than F3800 Plus. EcoFlow lists 80% or more after 4,000 cycles.

Which to choose

Choose the Anker SOLIX F3800 Plus if you want 6,000 W of output, up to 3,200 W of solar input and the longer expansion path, and can handle 135.6 lb. Choose the EcoFlow DELTA Pro 3 if you want the larger battery, the lighter unit, a 10 ms standby UPS and the 4,000-cycle rating, and 4,000 W of output (6,000 W with X-Boost) is enough. Think about where the unit will sit, since both weigh well over 100 lb. Our power outage checklist covers the rest of the plan.

Common questions

Keep comparing