EcoFlow DELTA 3 Max
#26 in LargeFull review
For buyers who want 2 kWh of fast-charging backup at a mid-range price and do not need heavy solar input.
Amazon $899$899
The EcoFlow DELTA 3 Max rates 3.7 among large portable power stations; the EcoFlow DELTA 3 Ultra rates 3.7 among home backup ones. The EcoFlow DELTA 3 Max costs $450 less ($899 vs $1,349).
EcoFlow DELTA 3 Ultra
#22 in Home backupFull review
A wheeled 3kWh station for home backup or RV use at a lower price than its expandable sibling. Buy it if 3kWh is enough and you charge mostly from the wall.
Amazon $1,699 EcoFlow $1,349$1,349
Prices were last checked October 24, 2026 and are subject to change; the price and availability shown by the retailer at the time of purchase apply.
Scores side by side
These two sit in different size classes (large and home backup), and each is scored against the reference points for its own class, so a rating says how well each does among its own size peers. How we rank explains each factor.
| Factor weight | EcoFlow DELTA 3 Max | EcoFlow DELTA 3 Ultra |
|---|---|---|
| Overall rating | 3.7/5 | 3.7/5 |
| Value 25% | 79 $0.44 per rated Wh | 79 $0.44 per rated Wh |
| Tested capacity 15% | 41 79% of rated capacity delivered (1 test) | 55 82% of rated capacity delivered (1 test) |
| Battery life 15% | 70 LiFePO4, 5-year warranty | 70 LiFePO4, 5-year warranty |
| AC output 15% | 54 2,400 W continuous AC | 37 3,600 W continuous AC |
| Charging speed 10% | 50 full AC charge time not published (neutral score used) | 50 full AC charge time not published (neutral score used) |
| Portability 10% | 100 101 Wh per kg (44.8 lb (20.3 kg)) | 89 94 Wh per kg (72.1 lb (32.7 kg)) |
| Solar input 5% | 11 500 W max solar input | 13 800 W max solar input |
| Features 5% | 75 UPS (10 ms), 100 W USB-C, app | 75 UPS (10 ms), 140 W USB-C, app |
Independent capacity tests
EcoFlow DELTA 3 Max
| Tested by | Usable AC energy | Of rated | Conditions |
|---|---|---|---|
| The Solar Lab | - | 79% | Efficiency test (load not stated in the review). Measured AC recharge 0-100% in 68 min; idle draw 27W. |
EcoFlow DELTA 3 Ultra
| Tested by | Usable AC energy | Of rated | Conditions |
|---|---|---|---|
| The Solar Lab | - | 82% | Efficiency test (load not stated in the review). Measured AC recharge 0-100% in 2 h from a standard household outlet. |
Specifications
| EcoFlow DELTA 3 Max | EcoFlow DELTA 3 Ultra | |
|---|---|---|
| Battery | ||
| Rated capacity | 2,048 Wh | 3,072 Wh |
| Tested usable capacity | 1,618 Wh (79%) | 2,519 Wh (82%) |
| Chemistry | LiFePO4 | LiFePO4 |
| Expandable | - | No |
| Output | ||
| AC output | 2,400 W (4,800 W surge) | 3,600 W (7,200 W surge) |
| Boost mode (resistive loads) | 3,400 W | 4,600 W |
| AC outlets | 4 total | 5 total |
| 120V 20A outlets (NEMA 5-20R) | 4 | 4 |
| RV 30A outlet (TT-30R) | - | 1 |
| AC waveform | Pure sine wave | Pure sine wave |
| USB-C ports | 3 (up to 100 W each) | 3 (up to 140 W each) |
| USB-A ports | 1 | 1 |
| 12 V car outlet | Yes | Yes |
| DC5521 ports | 0 | 0 |
| UPS / pass-through | Yes (10 ms switchover) | Yes (10 ms switchover) |
| Charging | ||
| AC charging | 1,800 W | 1,800 W |
| Max solar input | 500 W | 800 W |
| Car charging | 96 W | - |
| Build | ||
| Weight | 44.8 lb (20.3 kg) | 72.1 lb (32.7 kg) |
| Dimensions | 494 x 239 x 305 mm | 626 x 328 x 395 mm |
| App | Wi-Fi + Bluetooth | EcoFlow app (Wi-Fi and Bluetooth) |
| Warranty | 5 years | 5 years |
| Released | 2025-09 | 2025-09 |