EcoFlow DELTA 2 Max vs EcoFlow DELTA 3 Plus: manufacturer-published specifications compared

EcoFlow DELTA 2 Max vs EcoFlow DELTA 3 Plus: cheaper per watt-hour vs longer cycle rating

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Specifications checked against manufacturer pages on 2026-08-23.

The EcoFlow DELTA 2 Max (2,048 Wh, 2,400 W) and the EcoFlow DELTA 3 Plus (1,024 Wh, 1,800 W), compared on the figures their makers publish. On the normalized ratios, the DELTA 2 Max costs less per watt-hour ($0.63/Wh vs $0.78/Wh); the DELTA 3 Plus is rated for more cycles (4,000 vs 3,000).

In short. The DELTA 2 Max leads on cost per watt-hour ($0.63/Wh vs $0.78/Wh) and watt-hours per pound (41.0 Wh/lb vs 37.1 Wh/lb); the DELTA 3 Plus leads on rated cycle life (4,000 vs 3,000) and continuous watts per dollar (2.25 W/$ vs 1.85 W/$). 2 of 6 measures tie or are not comparable. Pick by the one your outage will test.

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Check the current price

EcoFlow DELTA 3 PlusEcoFlow DELTA 3 Plus on Amazon

Links go to the exact base unit we compared, not a bundle. Amazon prices change daily.

We do not link the DELTA 2 Max: we could not confirm a listing for the exact base unit, and we do not link a guess.

Specifications, side by side

Numbered notes below the table give the source location or a caveat for figures that need one; check marks mark the better figure where one can be judged; “Manufacturer does not state” means absent from that maker’s page as of its check date listed under Sources. UPS switchover is how long the outlets go dark when grid power drops.

Specification EcoFlow DELTA 2 Max EcoFlow DELTA 3 Plus
Rated capacity 2,048 Wh1 ✓ 1,024 Wh2
Usable capacity (calculated)* 1741–1843 Wh 870–922 Wh
Continuous AC output 2,400 W3 ✓ 1,800 W4
Surge output 4,800 W5 ✓ 3,600 W6
Full recharge from wall Manufacturer does not state (0–80% in 66 min)7 56 min8
Cell chemistry LFP (LiFePO4)9 LiFePO410
Rated cycle life 3,000 cycles to 80%+11,12 4,000 cycles to 80%13 ✓
UPS switchover <20 ms14 <10 ms15
Expandable Yes, up to 6,144 Wh16,17 Yes, up to 5,000 Wh18
Max solar input 1,000 W19 1,000 W20
Max AC charging input 1,800 W21 ✓ 1,500 W22
AC outlets 623 624
Highest USB-C port 100 W25 140 W26 ✓
App control Yes27 Yes28
Stated noise 30 dB29 <30 dB30
Warranty 5 years31 5 years32
Weight 50 lb33 about 27.6 lb34 ✓
Manufacturer list price when checked $1,29935 $79936 ✓

* Calculated: rated capacity × an assumed 85–90% conversion efficiency; no maker publishes a usable figure.

Notes on the figures

  1. DELTA 2 Max, rated capacity: Listed under “Capacity” on the manufacturer’s spec sheet for the base unit.
  2. DELTA 3 Plus, rated capacity: 1024Wh
  3. DELTA 2 Max, continuous output: Total continuous AC output across all six outlets.
  4. DELTA 3 Plus, continuous output: 1800W
  5. DELTA 2 Max, surge: Conventional surge rating; the page separately markets a boost mode of 3400 W for resistive loads.
  6. DELTA 3 Plus, surge: EcoFlow’s X-Boost raises sustained output to 2,200 W for resistive loads; 3,600 W is the surge figure. The two are different things.
  7. DELTA 2 Max, recharge: The manufacturer does not state a full 0-100% wall-recharge time. It states an 80% charge in 1.1 hours on AC alone, and 80% in 43 minutes when 1800 W AC input is combined with 600 W of solar input.
  8. DELTA 3 Plus, full recharge: With the 1,500 W AC input setting.
  9. DELTA 2 Max, cell chemistry: Listed under “Battery Chemistry” on the manufacturer’s spec sheet.
  10. DELTA 3 Plus, cell chemistry: Third-gen LiFePO4 (LFP) cells offer fast charging without sacrificing longevity.
  11. DELTA 2 Max, cycle life: Rated to the point where at least 80% of original capacity remains.
  12. DELTA 2 Max, cycle life: The manufacturer writes “80+%”, meaning 80 percent or more of the original capacity remains after the rated cycles.
  13. DELTA 3 Plus, cycle life: With 4000 cycles to 80% capacity, enjoy up to 10 years of reliable use, 25% above the industry standard.
  14. DELTA 2 Max, UPS switchover: Upper bound. The page states the auto-switch to battery power happens in under 20 milliseconds.
  15. DELTA 3 Plus, UPS switchover: Stated as under 10 ms; an upper bound.
  16. DELTA 2 Max, expandable: Capacity expands by attaching up to two extra batteries.
  17. DELTA 2 Max, expandable: Maximum system capacity with two extra batteries attached.
  18. DELTA 3 Plus, expandable: up to 5kWh expandable
  19. DELTA 2 Max, solar input: Total across the two solar input ports; a single port accepts up to 500 W.
  20. DELTA 3 Plus, solar input: 2 ports, DC Charge Input, 11V-60V 500W Max*2
  21. DELTA 2 Max, AC input: Maximum AC wall-charging input.
  22. DELTA 3 Plus, AC input: 1500W
  23. DELTA 2 Max, AC outlets: Six household AC outlets sharing a 2400 W total output.
  24. DELTA 3 Plus, AC outlets: 6 outlets, 1800W total (Surge 3600W)
  25. DELTA 2 Max, USB-C: Per port; the unit has two USB-C ports.
  26. DELTA 3 Plus, USB-C: 2 ports, 140W Max
  27. DELTA 2 Max, app: Controlled through the EcoFlow app; the spec sheet lists Wi-Fi and Bluetooth connectivity.
  28. DELTA 3 Plus, app: APP (TOU / Storm Warning Alert)
  29. DELTA 2 Max, noise: Measured at a distance of approximately 20 inches, with low charging input and a 500 W output load, per the page’s own footnote.
  30. DELTA 3 Plus, noise: Stated as under 30 dB at 600 W output and under 40 dB at 1,200 W; an upper bound at a stated load.
  31. DELTA 2 Max, warranty: The maker markets this as an “Extensive 5-Year Warranty” on the product page.
  32. DELTA 3 Plus, warranty: 5 years
  33. DELTA 2 Max, weight: Net weight of the base unit; the same spec sheet lists the metric weight as 23 kg.
  34. DELTA 3 Plus, weight: Manufacturer states ‘approx.’
  35. DELTA 2 Max, price: List price; a sale price of $1,049.00 was shown.
  36. DELTA 3 Plus, price: Manufacturer list price when checked; on sale at $669 that day.

The same specs, normalized

Ratios, so the bigger unit does not win by default.

Measure DELTA 2 Max DELTA 3 Plus
Cost per watt-hour $0.63/Wh ✓ $0.78/Wh
Watt-hours per pound 41.0 Wh/lb ✓ 37.1 Wh/lb
Surge headroom 2.00× 2.00×
Recharge rate Not comparable — EcoFlow does not state a full-recharge time for the DELTA 2 Max.
Rated cycle life 3,000 4,000 ✓
Continuous watts per dollar 1.85 W/$ 2.25 W/$ ✓

Definitions and direction of each ratio: How we verify.

What each one runs, for how long

Appliance DELTA 2 Max DELTA 3 Plus
Full-size refrigerator
150 W, 900 W start, 35% duty · eff. 80%–87%		 31–34 hr 16–17 hr
Mini fridge
70 W, 400 W start, 30% duty · eff. 70%–82%		 2.8–3.3 days 34–40 hr
CPAP without humidifier
40 W · eff. 70%–82%		 36–42 hr 18–21 hr
CPAP with heated humidifier
95 W · eff. 70%–87%		 15–19 hr 7.5–9.4 hr
Gas furnace blower
400 W, 1600 W start, 40% duty · eff. 80%–87% / 85%–90%		 10–11 hr 5.4–5.8 hr
1/3 hp sump pump
500 W, 1800 W start, 15% duty · eff. 85%–90%		 23–25 hr about 12 hr
Router and modem
20 W · eff. 70%–82%		 3.0–3.5 days 36–42 hr
Laptop
60 W · eff. 70%–82%		 24–28 hr 12–14 hr
1500W space heater
1500 W · eff. 85%–90% / 82%–88%		 about 1.2 hr about 0.6 hr

Calculated, not measured: hours = rated Wh × efficiency ÷ (appliance W × duty); assumptions on How we verify. “Unlikely to start”: start-up surge exceeds the stated surge rating.

What the differences mean

Price per watt-hour. At the list prices we checked, the DELTA 2 Max costs $0.63/Wh against $0.78/Wh for the DELTA 3 Plus. At list the DELTA 3 Plus is $500 cheaper ($799 vs $1,299) for 1,024 Wh vs 2,048 Wh. Prices move with sales; the ratio moves with them.

Weight for the capacity. The DELTA 2 Max carries 41.0 Wh/lb against 37.1 Wh/lb for the DELTA 3 Plus. Both are two-hands-and-a-flat-surface units; the difference matters if the unit moves between car, porch and basement.

Cycle rating. The DELTA 3 Plus is rated for 4,000 cycles against 3,000 for the DELTA 2 Max, both to the same remaining-capacity threshold — otherwise we would not compare them. At one full cycle a week the difference is measured in years, not months; at occasional outage use neither limit is reached.

Output for the money. 2.25 W/$ on the DELTA 3 Plus against 1.85 W/$ on the DELTA 2 Max: read this row first if the job is powering one heavy load rather than trickling many light ones.

Which one, and for whom

On normalized measures the two split evenly: the DELTA 2 Max leads on cost per watt-hour ($0.63/Wh vs $0.78/Wh) and watt-hours per pound (41.0 Wh/lb vs 37.1 Wh/lb); the DELTA 3 Plus leads on rated cycle life (4,000 vs 3,000) and continuous watts per dollar (2.25 W/$ vs 1.85 W/$). Which figure settles it depends on what you need to keep running:

  • CPAP overnight. Switchover: DELTA 2 Max under 20 ms, DELTA 3 Plus under 10 ms. A 40 W CPAP runs roughly 36–42 hr on the DELTA 2 Max and 18–21 hr on the DELTA 3 Plus. Both run the night; both switchover figures are upper bounds, so they are too close to call from published numbers.
  • Keeping a refrigerator cold. Check start-up before runtime. The DELTA 2 Max states a 4,800 W surge rating; the DELTA 3 Plus states a 3,600 W surge rating. A full-size refrigerator needs about 900 W to start.
  • A multi-day outage with a generator or solar to recharge from. Full recharge: DELTA 2 Max 0–80% in 66 min (no full-charge time stated), DELTA 3 Plus 56 min. These are not comparable: EcoFlow states no full-charge time for the DELTA 2 Max.

Check the current price

EcoFlow DELTA 3 PlusEcoFlow DELTA 3 Plus on Amazon

Links go to the exact base unit we compared, not a bundle. Amazon prices change daily.

We do not link the DELTA 2 Max: we could not confirm a listing for the exact base unit, and we do not link a guess.

Related reading

A 1,024–2,048 Wh battery cannot do what a gasoline generator does — the runtime table shows a 1,500 W space heater emptying either unit in 0.6–1.2 hr — but it also cannot poison a household. The safety half of that trade-off is in our CPSC revision matrix of generator carbon-monoxide death counts, and this page puts every verified unit on the same refrigerator scenario.

Ordering before a storm? Check the arrival date at checkout — a unit that ships tomorrow can beat a better one that ships next week. Amazon Prime includes fast delivery on eligible items and starts with a free trial; we earn a commission if you join.

Sources and method

Published specifications only; no bench tests. Method: How we verify. More: Comparisons.