EcoFlow DELTA 3 Max
- usable
- 2,048 Wh
- output
- 2,400 W
- surge
- 4,800 W
- weight
- 20.3 kg
- recharge
- 68 min
#4 of 15
in the Large (2 kWh class) class
Lifted by Capacity & expansion and Quiet / livability; held back by charging & solar.
$670 below its $1,499 list price (45% off)
Verdict computed from this model's own tracked price history.
Capacity truth
The watt-hour number on the box isn't what reaches your devices. Same scale, three readings.
The marketing number — total cell capacity.
Also independently measured
- Fan noise
- 30–35 dB
- AC charge time
- 0–80 min
30-35 dB idle to 50-60 dB heavy load (BatteryEssence)
~68 min full; 0-80% ~1.13h (multiple review sites)
How it scores
Four buyer pillars over seven sub-scores — computed from sourced data with a published formula, price-independent by design.
Power
Usable capacity and how much you can run at once.
Usable watt-hours and how far you can grow it with add-on batteries, versus its size class.
Continuous and surge wattage, outlet count, and USB-C fast-charging.
Trust
Owner reputation, safety record, warranty, and build durability.
Owner ratings, brand reputation, recall record, and warranty backing.
Rated cycle life, warranty length, cell chemistry, and weather sealing.
Charging
Wall and solar recharge speed.
Wall recharge speed, solar input, and multi-source charging.
Livability
Lightweight, portable, and quiet enough to live with.
Weight, footprint, handle, and wheels, versus its size class.
Fan noise under load — quieter is better for bedrooms and CPAP use.
How this score is computed
The BatteryRank score is computed from sourced data with a published formula — ranked by data, not lab testing. Seven sub-scores blend into a 0–100 composite, grouped into four buyer pillars. Price is deliberately not a scoring input: prices move daily, so value intelligence lives in the price section above, judged against this model's own history.
| Pillar | Built from | Weight |
|---|---|---|
| Power | Capacity & expansion + Output & versatility | 38% |
| Trust | Trust & reliability + Durability & longevity | 33% |
| Charging | Charging & solar | 16% |
| Livability | Portability + Quiet / livability | 13% |
Scores are cohort-relative — each model is ranked against others in its size class. Missing inputs renormalize out rather than scoring zero (a model is never penalized for a spec nobody in its class publishes), and any figure resting on a documented estimate is tagged est. A full methodology page is coming.
Full specifications
Manufacturer-claimed unless marked verified (FCC/UL/DOE/lab). Hover any figure for its source.
Capacity & battery
- Usable capacity
- 2,048 Wh
- Rated cycle life
- 4,000 cycles
- Battery chemistry
- LiFePO4
- Rated capacity
- 2,048 Wh
- Cycle-life threshold
- 80 %
How much energy you can actually pull out of a full charge — the number that determines real runtime, not a marketing headline figure.
How many full charge-and-drain cycles before the battery drops to its rated threshold (shown alongside — brands rate to different thresholds, so never compare bare cycle counts).
The type of battery cell. LiFePO4 (LFP) cells last far more cycles and are more thermally stable than older lithium-ion (NMC) cells.
The battery's nameplate energy capacity — the headline number on the box. Real runtime comes from usable capacity and conversion losses, shown separately.
The remaining-capacity level the cycle rating is measured to. 3,000 cycles to 80% is a stronger battery than 3,000 cycles to 70% — always read the two numbers together.
Power output
- Continuous power output
- 2,400 W
- Surge power output
- 4,800 W
- AC outlets
- 4 outlets
- USB-A ports
- 1 ports
- USB-C ports
- 3 ports
- USB-C max output
- 100 W
- 12V car ports
- 1 ports
- DC barrel ports
- 0 ports
- Max combined output
- 2,400 W
The most power you can draw at once, sustained — this has to be higher than the running wattage of whatever you're plugging in.
A brief power spike the unit can absorb when a device first switches on — matters for things with motors or compressors, like fridges.
How many standard wall-style outlets are built in.
How many USB-A ports are built in, for charging older phones, lights, and accessories.
How many USB-C ports are built in — check the per-port wattage below if you need fast charging for a laptop.
The fastest a single USB-C port can charge a device — relevant for laptops and fast-charging phones.
How many car-socket (cigarette-lighter) style 12V outputs are built in — what CPAPs and car fridges plug into for the most efficient overnight running.
How many round barrel-style DC outputs are built in, used by routers, some lights, and older electronics.
The most power the unit can deliver across ALL ports at the same time — can be lower than the AC rating plus every USB port added up.
Charging & solar
- AC recharge speed
- 1,800 W
- AC charge time (0–100%)
- 68 min
- Max solar input
- 500 W
How fast the unit recharges from a wall outlet — higher means shorter waits between uses.
How long a full recharge takes from a wall outlet, start to finish.
The most solar panel wattage the unit can accept — undersized panels just mean slower charging, not damage, but oversizing this is wasted money.
Reliability & durability
- UPS switchover time
- 10 ms
How fast the unit takes over when grid power cuts out. Under ~20ms is fast enough that most electronics — including many CPAP machines — won't even blip.
Size & portability
- Weight
- 20.3 kg
How much the unit weighs on its own, without accessories — relevant for portability and carrying it up stairs during an outage.
What reviewers & owners report
Aggregated from named outlets and marketplaces — we own no hardware and never fabricate impressions.
- NA standalone (plain DELTA 3 Max not a distinct Amazon US listing; a 4.6/2218 aggregate cited spans variants). Reviewers praise fast ~68min charge, 2kWh in mid size, expandability — Amazon reviewers
- 2kWh LFP in a mid-size chassis; very fast ~68min AC charge; expandable; quiet (<=25dB at 600W); X-Boost 3400W; Wi-Fi/BT app; 5-yr (3+2) coverage — Across reviewers
- NA standalone; note 2400W continuous is lower than Max Plus 3000W; single USB-A — Amazon reviewers
- 2400W continuous (below Max Plus 3000W); only 1 USB-A; solar capped 500W (vs 1000W on Max Plus); plain Max harder to find at US retail than Max Plus — Across reviewers
- Wirecutter: none
- Popular Mechanics: none
- covered as a mid-tier 2kWh option; no single measured consensus captured for the plain Max variant — YouTube reviewers
Brand reputation: 2025 model; DELTA 3 family well-regarded. Plain Max less prominent at US retail than Max Plus. Brand-level: EcoFlow DELTA Max 2000 (EFD310) fire recall 2025-10 (OLDER separate product, not DELTA 3 Max)
Sources: us.ecoflow.com/products/delta-3-max-series-portable-power-station?view=d3m (on-page Specs, Max variant) accessed 2026-07-04; backuppowerhub.com, batteryessence.com, voltagebasics.com; saferproducts.gov (EcoFlow) checked 2026-07-04